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EXAMPLES - EXEMPLOS
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CASE REPORT
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Enteritis Caused by Type 2c Canine Parvovirus in a 5-Year-Old Dog
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Veronica Machado Rolim1, Luciana Sonne1, Renata Assis Casagrande2, Suyene Oltramari
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Souza1, Luciane Dubina Pinto3, Angelica Terezinha Barth Wouters4, Flademir Wouters4,
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Cláudio Wageck Canal3 & David Driemeier1
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Setor de Patologia Veterinária (SPV), Faculdade de Veterinária (FaVet), Universidade
Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil. 2Patologia Veterinária,
Universidade do Estado de Santa Catarina (UDESC), Lages, SC, Brazil. 3Setor de Virologia,
FaVet, UFRGS, Porto Alegre, RS. 4 Setor de Patologia Veterinária, Universidade Federal de
Lavras (UFL), Lavras, MG, Brazil. CORRESPONDENCE: D. Driemeier
[[email protected] - Tel.: +55 (51) 3308-6107]. Faculdade de Veterinária - UFRGS. Av.
Bento Gonçalves n. 9090, Bairro Agronomia. CEP 91540-000 Porto Alegre, RS, Brazil.
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ABSTRACT
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Background: Canine parvovirosis, caused by canine parvovirus type 2 (CPV-2), emerged in
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the 1970s as an important disease affecting dogs, causing severe hemorrhagic gastroenteritis
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and death. It can occur in any breed, gender, and age; however, puppies of 4 to 12 weeks of
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age are most commonly afflicted. In 2000 a new variant of the virus, called CPV-2c, was
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discovered, and has been related to hemorrhagic gastroenteritis in dogs with up to 2 years of
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age, although some cases have been described in older animals with a full vaccination history.
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This paper reports a case of enteritis by canine parvovirus type 2c (CPV-2c) in a 5-year-old
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dog.
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Case: At necropsy a pallid oral and conjunctival mucosae were observed. The small intestine
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showed a very reddish and wrinkled serosa, the wall was thickened, the mucosae was
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diffusely wrinkled and yellowed with evidenced Peyer plaques and there was no content in
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the final portion of the intestine. The mesenteric lymph nodes were enlarged and reddish.
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Multiple suffusions on the serosa of the stomach, and petechiae and subepicardial suffusions
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in the heart were observed. The histological findings were, collapse of the lamina propria of
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the small intestine, and fusion of the villi, necrosis of enterocytes, atrophy and the
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disappearance of crypts, with dilation of remaining crypts showing large rounded nuclei with
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one or two evident nucleoli, exhibiting accentuated cellular pleomorphism in some cases
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forming syncytia. In addition, there were bacterial colonies and fibrin adhered to the mucosae.
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The serosa showed diffuse congestion, marked transmural multifocal hemorrhage, thrombosis
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and fibrin deposition on the serosa surface. Necrosis of the germinative centers with moderate
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lymphoid depletion was observed in the lymphoid aggregates of the large intestine. In the
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bone marrow, spleen and mesenteric lymph node there were accentuated lymphoid depletion,
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hemorrhage and moderate hemosiderosis. The remaining tissue of the thymus showed
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accentuated multifocal to coalescent hemorrhage. The anti-parvovirus IHC showed intense
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immunostaining of the cytoplasm of epithelial cells, mainly in the crypts of the small
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intestine. In the spleen and lymph node there was intense immunostaining in the lymphocytes
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of follicular centers. The PCR and sequencing techniques applied to the sample allowed the
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identification of CPV-2c.
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Discussion: Diarrhea in dogs has been associated with a wide variety of viral agents; the
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canine parvovirus, rotavirus and coronavirus being the main primary pathogens involved.
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Since CPV-2 emerged at the end of the 1970s this pathogen has gained great importance in
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the care of dogs and is probably the most common infectious disease of canine species.
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Shortly after appearing in the canine population, CPV-2 underwent alterations in some of its
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amino acids, which resulted in new and better adapted viral strains. Studies in which
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circulating viral strains have been identified have demonstrated the importance of CPV-2c in
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outbreaks of parvovirosis in previously vaccinated puppies. There are few reports of the
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detection of CPV-2c in adult dogs. The majority of cases described relate to dogs up to 2 ½
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years of age, one exception being a case involving a 12-year-old dog This new variant of
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CPV-2 should be considered as an important pathogen in the diagnosis of causes of
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sanguinolent diarrhea in adult dogs.
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Keywords: CPV-2c, adult dogs, parvovirus, enteric disease.
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INTRODUCTION
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Canine parvovirosis, caused by canine parvovirus type 2 (CPV-2), emerged in the
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1970s as an important disease affecting dogs, causing severe hemorrhagic gastroenteritis and
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death [1]. It can occur in any breed, gender, and age; however, puppies of 4 to 12 weeks of
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age are most commonly afflicted [5,11]. CPV-2 was rapidly replaced with the new antigenic
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variants CPV-2a and CPV-2b [7]. In 2000 a new variant of the virus, called CPV-2c [4], was
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discovered, and has since been reported in several parts of the world, including Brazil [13,14].
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This variant has been related to hemorrhagic gastroenteritis in dogs with up to 2 years of age
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[4,7,8], although some cases have been described in older animals with a full vaccination
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history [6,7]. The aim of this study was to describe a case of parvovirosis caused by variant 2c
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(CPV-2c) in a 5-year-old dog, with immunohistochemical and molecular characterization.
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CASE
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A 5-year-old male mixed breed dog was submitted to necropsy with a history of
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intense sanguinolent diarrhea over three days, vomiting, dehydration, marked apathy and
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anorexia. It was reported that the dog had received three doses of commercial vaccine against
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parvovirus, canine distemper, adenovirus type 1, adenovirus type 2 and parainfluenza at 45,
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66 and 87 days of age, however, it received no yearly revaccination.
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At necropsy a good physical condition, pallid oral and conjunctival mucosae were
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observed. The small intestine showed a very reddish and wrinkled serosa (Figure 1a), the wall
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was thickened, the mucosae was diffusely wrinkled and yellowed (Figure 1b) with evidenced
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Peyer plaques and there was no content in the final portion of the intestine. The mesenteric
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lymph nodes were enlarged and reddish. Multiple suffusions on the serosa of the stomach, and
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petechiae and subepicardial suffusions in the heart were observed.
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Several organs were collected, fixed in 10% formalin, routinely processed for
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histological examination and stained with hematoxylin and eosin. Feces samples were
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collected from the rectum for viral detection. The tissue samples were submitted to the
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immunohistochemical (IHC) technique with anti-parvovirus monoclonal antibody (MCA
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2064) by the peroxidase-bound streptavidin-biotin method [12]. The extraction of viral DNA
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from the fecal sample for the detection of CPV was performed as described previously [2].
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The PCR was carried out for the amplification of 583 bp (base pairs) of the VP2 gene
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(position 4003-4585), using a previously described protocol [4].
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The histological findings were, collapse of the lamina propria of the small intestine,
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and fusion of the villi, necrosis of enterocytes, atrophy and the disappearance of crypts, with
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dilation of remaining crypts showing large rounded nuclei with one or two evident nucleoli,
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exhibiting accentuated cellular pleomorphism in some cases forming syncytia (Figure 1c). In
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addition, there were bacterial colonies and fibrin adhered to the mucosae. The serosa showed
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diffuse congestion, marked transmural multifocal hemorrhage, thrombosis and fibrin
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deposition on the serosa surface. Necrosis of the germinative centers with moderate lymphoid
100
depletion was observed in the lymphoid aggregates of the large intestine. In the bone marrow,
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spleen and mesenteric lymph node there were accentuated lymphoid depletion, hemorrhage
102
and moderate hemosiderosis. The remaining tissue of the thymus showed accentuated
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multifocal to coalescent hemorrhage.
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The anti-parvovirus IHC showed intense immunostaining of the cytoplasm of
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epithelial cells, mainly in the crypts of the small intestine (Figure 1d). In the spleen and lymph
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node there was intense immunostaining in the lymphocytes of follicular centers (Figure 1e).
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In the liver, staining was observed in the cytoplasm of Kupffer cells. In the bone marrow there
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was staining mainly in the cytoplasm of a few cells (Figure 1f).
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The application of the PCR and sequencing techniques detected CPV-2c. The partial
amplification of the VP2 gene revealed a single band with the expected size of 583bp.
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DISCUSSION
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Diarrhea in dogs has been associated with a wide variety of viral agents; the canine
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parvovirus, rotavirus and coronavirus being the main primary pathogens involved [11]. Since
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CPV-2 emerged at the end of the 1970s this pathogen has gained great importance in the care
115
of dogs and is probably the most common infectious disease of canine species [11]. Shortly
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after appearing in the canine population, CPV-2 underwent alterations in some of its amino
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acids, which resulted in new and better adapted viral strains [4,7].
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CPV-2c was detected for the first time in 2000 and rapidly spread to diverse regions of
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the world [4,8,13,14]. Although cases of parvovirosis are typically associated with puppies of
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4 to 12 weeks of age, the period in which a decrease in the maternal antibodies occurs, a case
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of parvovirosis in a 5-year-old dog is reported herein. The clinical signs, as well as the
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macroscopic and microscopic findings for this dog are similar to those described for other
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fatal cases of canine parvovirosis [3,12].
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Studies in which circulating viral strains have been identified have demonstrated the
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importance of CPV-2c in outbreaks of parvovirosis in previously vaccinated puppies
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[8,13,14]. There are few reports of the detection of CPV-2c in adult dogs [6,7]. The majority
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of cases described relate to dogs up to 2 ½ years of age, one exception being a case involving
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a 12-year-old dog [7].
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Hemorrhagic gastroenteritis in dogs can sporadically be associated with intestinal
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infections by type A Clostridium perfringens, parasitism by Ancylostoma caninum, [3] and
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Cryptosporidium parvum [9]. Recently a new canine circovirus (DogCV) was described in the
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liver of a dog with severe hemorrhagic gastroenteritis, vasculitis, and granulomatous
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lymphadenitis [10]. DogCV also could be a complicating factor in other canine infectious
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diseases, as with PCV2 [10].
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In conclusion, CPV-2, besides being a principal infectious agent in young dogs, has
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evolved the new variant 2c which should be considered an important pathogen in the
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differential diagnosis of the causes of sanguinolent diarrhea.
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Declaration of interest. The authors report no conflicts of interest. The authors alone are
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responsible for the content and writing of the paper.
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REFERENCES
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1 Appel M.J.G., Scott F.W. & Carmichael L.E. 1979. Isolation and immunisation studies
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of a canine parvo-like virus from dogs with haemorrhagic enteritis. Veterinary Record.
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105: 156-159.
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2 Boom R., Sol C.J.A., Salimans M.M.M., Jansen C.L., Wertheim-van Dillen P.M.E. &
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Noordaa V.D. 1990. Rapid and simple method for purification of nucleic acids. Journal of
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Clinical Microbiology. 28: 495-503.
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3 Brown C.C., Baker D.C. & Barker I.K. 2007. Alimentary system. In: Maxie M.G. (Ed.).
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Jubb, Kennedy, and Palmer’s Pathology of Domestic Animals. 5th edn. v.2. Philadelphia:
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Saunders Elsevier, pp.3-293.
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4 Buonavoglia C., Martella V., Pratelli A., Tempesta M., Cavalli A., Buonavoglia D.,
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Bozzo G., Elia G., Decaro N. & Carmichael L. 2001. Evidence for evolution of canine
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parvovirus type 2 in Italy. Journal of General Virology. 82(12): 3021-3025.
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5 Decaro N. & Buonavoglia C. 2012. Canine parvovirus - A review of epidemiological and
diagnostic aspects, with emphasis on type 2c. Veterinary Microbiology. 155: 1-12.
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6 Decaro N., Cirone F., Desario C., Elia G., Lorusso E., Colaianni M.L., Martella V. &
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Buonavoglia C. 2009. Severe parvovirus in a 12-year-old dog that had been repeatedly
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vaccinated. Veterinary Record. 164: 593-595.
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7 Decaro N., Desario C., Elia G., Martella V., Mari V., Lavazza A., Nardi M. &
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Buonavoglia C. 2008. Evidence for immunisation failure in vaccinated adult dogs infected
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with canine parvovirus type 2c. New Microbiologica. 31: 125-130.
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8 Decaro N., Martella V., Desario C., Bellacicco A.L., Camero M., Manna L., D’Aloja
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D. & Buonavoglia C. 2006. First detection of canine parvovirus type 2c in pups with
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haemorrhagic enteritis in Spain. Journal of Veterinary Medical Science. 53(10): 468-472.
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9 Hall E.J. & German A.J. 2005. Diseases of the small intestine. In: Ettinger S.J. &
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Feldman E.C (Eds). Veterinary Internal Medicine. 6th edn. v.2. St. Louis: Elsevier
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Saunders, p.1332-1377.
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10 Li L., McGraw S., Zhu K., Leutenegger C.M., Marks S.L., Kubiski S., Gaffney P.,
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Dela Cruz Jr. F.N., Wang C., Delwart E. & Pesavento P.A. 2013. Circovirus in tissues
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of dogs with vasculitis and hemorrhage. Emerging Infectious Diseases. 1994): 534-541.
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11 Mccaw D.L. & Hoskins J.D. 2006. Canine viral enteritis. In: Greene C.E. (Ed). Infectious
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diseases of the dog and cat. Cap.8. St. Louis: Elsevier Saunders, pp.63-73.
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12 Oliveira E.C., Pescador C.A., Sonne L., Pavarini S.P., Santos A.S., Corbellini L.G. &
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Driemeier D. 2009. Análise imuno-histoquímica de cães naturalmente infectados pelo
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parvovírus canino. Pesquisa Veterinária Brasileira. 29(2): 131-136.
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13 Pinto L.D., Streck A.F., Gonçalves K.R., Souza C.K., Corbellini A.O., Corbellini L.G.
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& Canal C.W. 2010. Typing of canine parvovirus strains circulating in Brazil between
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2008 and 2010. Virus Research. 165(1): 29-33.
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14 Streck A.F., Souza C.K., Gonçalves K.R., Zang L., Pinto D.B. & Canal C.W. 2009.
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First detection of canine parvovirus type 2c in Brazil. Brazilian Journal of Microbiology.
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40(3): 465-469.
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Figure 1. Canine parvovirosis in dog. Small intestine: A: very reddish and wrinkled serosa.
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B: thickened intestinal wall and mucosae diffusely wrinkled and yellowed. C: collapsed
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intestinal lamina propria, with fusion of the villi, atrophy and disappearance of crypts, and
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dilation of the remaining crypts (HE, Obj. 10). Immunohistochemistry for CPV-2, Biotin-
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streptavidin peroxidase method: D: small intestine with staining of enterocytes, mainly of
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crypts (Obj. 10). E: lymph node with immunostaining in lymphocytes of follicular centers
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(Obj. 20). F: bone marrow with staining in few cells (Obj. 40).
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CASE REPORT
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Aspectos histopatológicos e imuno-histoquímicos da raiva em raposas
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Cerdocyon thous
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Histopathological and Immunohistochemical Aspects of Rabies in Foxes
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Cerdocyon thous
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Jeann Leal de Araújo1, Antônio Flavio Medeiros Dantas1, Glauco José Nogueira de
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Galiza2, Pedro Miguel Ocampos Pedroso3, Maria Luana Cristiny Rodrigues Silva1,
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Luciano da Anunciação Pimentel4 & Franklin Riet-Correa1
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1
Hospital Veterinário, Laboratório de Patologia Animal, CSTR, UFCG, Campus de Patos, PB,
Brazil. 2Laboratório de Patologia Veterinária, Departamento de Patologia, CCS, UFSM, Santa
Maria, RS, Brazil. 3Laboratório de Patologia Veterinária, CCA, UFRB, Cruz das Almas, BA,
Brazil. 4Universidade de Cuiabá, Cuiabá, MT, Brazil. CORRESPONDENCE: A.F.M. Dantas
[[email protected] - Tel.: +55 (83) 9929-8064]. Hospital Veterinário, Laboratório de
Patologia Animal, CSTR, UFCG, Campus de Patos. Avenida Universitária S/N, Santa
Cecilia. CEP 58708-110 Patos, PB, Brazil.
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ABSTRACT
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Background: Several wild canids are considered reservoirs of rabies virus in the Northeast of
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Brazil, two wild canids have been reported as reservoirs of rabies virus Cerdocyon thous
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(crab-eating fox) and Pseudalopex vetulus (hoary fox) (previously called Dusicyon vetulus).
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The diagnosis of rabies in foxes is usually performed through fluorescent antibody test (FAT)
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and mouse inoculation test (MIT). However, until the moment, there are no detailed
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histopathological and immunohistochemical (IHC) description studies in foxes affected by
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this disease studies. Therefore, the aim of this work was the characterization of pathological
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and IHC findings of foxes with rabies sent to the Laboratory of Animal Pathology (LPA) of
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the Federal University of Campina Grande (UFCG) in Patos, semiarid region of Paraiba,
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Brazil.
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Case: Two foxes were sent to the LPA, phenotypic species identification through analysis of
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morphological aspects was performed and posteriorly necropsied. Fragments of organs of the
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thoracic and abdominal cavities, salivary glands, eye and Gasser ganglia were collected in
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addition to the central nervous system (CNS) that was collected integer and fixed at 10%
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buffered formalin. Later, serial sections of the 16 fragments of the CNS were performed,
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measuring about 0.5 cm thick and cleaved. Fragments of cerebrum, cerebellum, brainstem,
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spinal cord and salivary glands were sent to performing FAT and MIT. Paraffin blocks with
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fragments of the hippocampus were selected and submitted to IHC. Macroscopically, the two
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foxes had multiple skin lacerations, bone fractures and ruptures of abdominal organs from
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injuries. The vessels of the meninges were slightly congested. Histologically, the CNS had
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diffuse non-suppurative encephalitis, with inflammatory infiltrate composed primarily by
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lymphocytes and plasma cells, forming mononuclear perivascular cuffing, and gliosis
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associated with mild eosinophilic intracytoplasmic inclusion corpuscles primarily in neurons
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of the cortex, basal ganglia, hippocampus, thalamus, colliculi, bridge, obex and cerebellum.
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Meningitis and mild myelitis non-suppurative were also observed in both cases with rare viral
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inclusions in spinal cord neurons. Similar inflammation was also observed in the Gasser
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ganglion and in others peripheral nerve ganglia. Adrenal and salivary glands showed
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multifocal areas of moderate mononuclear inflammatory infiltrate composed mainly by
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macrophages and plasma cells. Strong positive IHC labeling was observed for rabies in the
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neurons in different brain regions, especially in the cerebral cortex and in Purkinje cells of the
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cerebellum. In both cases the diagnosis of rabies was confirmed by immunofluorescence and
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mouse inoculation.
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Discussion: The diagnosis of rabies in foxes wasconducted through the characteristic
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histopathologic findings of the disease observed in the CNS and confirmed by the FAT, MIT
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and IHC. Although the histopathological findings in foxes are similar to what is observed in
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other species, the severity of inflammatory lesions and the large amount of inclusion bodies in
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the nervous tissue is an outstanding feature, regardless of the inflammatory response. The
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diagnosis of rabies in foxes can be achieved by characteristic histopathologic findings of the
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CNS, supported by evaluating peripheral nerve ganglia, salivary glands and adrenal which
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may also present similar microscopic lesions. Auxiliary Laboratory tests must be performed,
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such as FAT, MIT and IHC for confirmation of the disease.
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Keywords: wild animals, canids, Lyssavirus.
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Descritores: animais selvagens, canídeos, Lyssavirus.
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INTRODUÇÃO
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Vários canídeos silvestres são considerados reservatórios do vírus rábico, a exemplo
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da raposa vermelha (Vulpes vulpes), distribuída mundialmente na Europa, América do Norte,
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norte da África e na Austrália [4].
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No Brasil, o ciclo silvestre terrestre da raiva é representado principalmente por saguis
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(Callithrix jacchus) ou raposas (Cerdocyon thous). Na região Nordeste, dois canídeos
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silvestres já foram relatados como reservatórios do vírus rábico: Cerdocyon thous (crab-eating
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fox, cachorro-do-mato) e Pseudalopex vetulus (hoary fox, raposa cinzenta) (previamente
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denominada Dusicyon vetulus) [3,6].
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transmissão para humanos nos estados do Ceará, Paraíba, Pernambuco, Bahia e Minas Gerais
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[1,2] e dos 329 casos de raiva notificados no período de 2002 a 2009, cerca de 88% eram de
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canídeos silvestres, todos ocorridos na região Nordeste, onde muitos desses eram mantidos
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como animais de estimação. Segundo dados da Secretaria de Vigilância em Saúde (SVS/MS)
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[13], no Brasil, os canídeos silvestres foram responsáveis por 7,9% dos 165 óbitos de
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humanos com raiva, no período de 1986-2006. No Estado da Paraíba entre os anos de 2007 e
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2010, foram notificados sete casos de raiva em cães e gatos, e cinco casos em canídeos
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silvestres [13].
Existem relatos de casos de raposas com raiva e
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Até o momento, não existem estudos detalhados de descrição histopatológica e imuno-
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histoquímica em raposas acometidas por essa doença, portanto, o objetivo do presente
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trabalho é a caracterização dos achados patológicos e imuno-histoquímicos de raposas com
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raiva encaminhadas ao Laboratório de Patologia Animal (LPA) da Universidade Federal de
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Campina Grande (UFCG) em Patos, semiárido da Paraíba, Brasil.
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CASOS
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As raposas utilizadas foram encaminhas mortas para o LPA da UFCG, realizada a
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identificação fenotípica da espécie através da análise de aspectos morfológicos do animal com
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base no Guia de Identificação de Canídeos Brasileiros [10] e posteriormente necropsiadas.
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Foram coletados fragmentos de órgãos das cavidades torácica e abdominal, glândulas
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salivares, globo ocular e gânglio de Gasser, além do sistema nervoso central (SNC) que foi
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coletado e fixado em formol tamponado a 10%. Posteriormente foram realizados cortes
12
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seriados do encéfalo, medindo aproximadamente 0,5 cm de espessura e clivados 16
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fragmentos do SNC identificados: 1) córtex frontal, 2) córtex parietal, 3) córtex temporal, 4)
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córtex occipital, 5) núcleos da base, 6) hipocampo, 7) tálamo, 8) colículo rostral, 9) colículo
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caudal, 10) pedúnculos cerebelar, 11) ponte, 12) óbex, 13) cerebelo, 14) medula cervical, 15)
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medula torácica e 16) medula lombar. Para a confecção das lâminas histológicas, os
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fragmentos clivados foram processados rotineiramente e coradas pela técnica de hematoxilina
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e eosina (HE).
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Seguindo protocolos estabelecidos previamente [5,8] foram realizadas as técnicas de
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imunofluorescência direta (IFD) e inoculação intracerebral em camundongos (ICC),
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respectivamente, em fragmentos do cérebro, cerebelo, tronco encefálico, medula espinhal e
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glândulas salivares das raposas foram enviados para a execução dessas técnicas.
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Blocos de parafina com fragmentos do hipocampo foram selecionados e submetidos à
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técnica de imuno-histoquímica para a detecção do vírus da raiva. Após desparafinizanação e
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reidratação dos tecidos, foi realizada recuperação antigênica com solução de citrato (pH 6,0)
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em forno micro-ondas, em potência máxima, por dez min. O anticorpo primário utilizado era
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policlonal para raiva produzido em cabras marcado com FITC (anticorpo conjugado de
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isotiocianato de fluorescência - Chemicon #5199)1, diluído 1:1000 em solução tamponada
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fosfato salina (PBST) com Tween® 20 (Sigma P2287)2, e incubado por 60 min a 37Cº. O
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anticorpo
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(LSAB+System HRP)3 foram utilizados consecutivamente, incubados à temperatura ambiente
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por 30 min e marcados através da adição do DAB + Substrate - Choromogen System3 e contra
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corados com hematoxilina de Harris. Como controle positivo foi utilizado secções
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histológicas de casos confirmados de raiva em bovinos. Como controle negativo, as mesmas
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secções foram utilizadas, com substituição do anticorpo primário por PBST.
secundário
biotilinilado
e
o
complexo
estreptavidina-biotina-peroxidase
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Esses casos ocorreram em anos distintos, sendo o primeiro em maio de 2010 e o
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segundo em abril de 2013. As duas raposas enviadas foram identificadas como pertencentes à
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espécie Cerdocyon thous. Segundo informações obtidas dos moradores da zona rural do
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Município de São José de Espinharas - PB, local onde os animais foram encontrados, as
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raposas foram atropeladas após terem sido vistas com sinais nervosos caracterizados por
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incoordenação, perda de equilíbrio, acentuado balançar compulsivo da cabeça e aparente
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debilidade muscular.
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Macroscopicamente as duas raposas apresentavam múltiplas lacerações cutâneas,
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fraturas ósseas e rupturas de órgãos abdominais provenientes de traumatismos. Os vasos das
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leptomeninges estavam levemente congestos.
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Histologicamente verificou-se reação inflamatória mononuclear, principalmente no
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SNC, variando no grau de intensidade e sua localização (Tabela 1). Havia encefalite não
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supurativa, caracterizada pela presença de infiltrado inflamatório constituído principalmente
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por linfócitos e plasmócitos, formando manguitos perivasculares (Figura 1A), associada a
323
discreta gliose e corpúsculos de inclusões eosinofílicos intracitoplasmáticos principalmente
324
em neurônios dos córtices, núcleos da base, hipocampo (Figura 1B), tálamo, colículos, ponte,
325
óbex e cerebelo. Meningomielite linfoplasmocitária discreta com raras inclusões virais em
326
neurônios da medula espinhal também foram observadas nos dois casos.
327
Inflamação semelhante também foi observada nos gânglios nervosos periféricos,
328
glândulas salivares e adrenais dos dois casos. Havia infiltrado inflamatório principalmente de
329
linfócitos e plasmócitos entre os feixes nervosos do gânglio de Gasser, caracterizando
330
ganglioneurite
331
intracitoplasmáticas em neurônios. Ganglioneurite não supurativa também foi observada no
332
gânglio ciliar do primeiro caso. Infiltrado linfoplasmocitário também foi encontrado nas
333
glândulas salivares (Figura 1D) e nas adrenais dos dois casos, característicos de adenite e
não
supurativa
(Figura
1C),
associada
a
raras
inclusões
virais
14
334
adrenalite não supurativa. Corpúsculos de inclusões raramente foram verificados em
335
agregados de neurônios distribuídos perifericamente a essas estruturas glandulares.
336
337
No exame de IFD e na ICC o resultado foi positivo em todos os fragmentos testados
para o vírus da raiva.
338
Pela imuno-histoquímica os dois casos marcaram fortemente com anticorpos para o
339
vírus rábico, demonstrando múltiplos agregados de grânulos distribuídos no pericário, como
340
também na forma de corpúsculos grandes, únicos ou múltiplos no citoplasma de neurônios do
341
córtex (Figura 2A) e ponte (Figura 2B). No controle negativo não foram observadas nenhum
342
tipo de imunomarcação (Figura 2C).
343
344
345
346
DISCUSSÃO
O diagnóstico da raiva em raposas foi realizado através dos achados histopatológicos
característicos da doença, observados no SNC e confirmados pela IFD, ICC e IHQ.
347
Apesar dos achados histopatológicos encontrados nas raposas serem semelhantes ao
348
que são observados em outras espécies [14], a severidade das lesões inflamatórias e a grande
349
quantidade de corpúsculos de inclusão no tecido nervoso é uma característica marcante,
350
independente da resposta inflamatória. A inflamação não supurativa e a presença de inclusões
351
observadas nos gânglios nervosos periféricos encontrados ao redor ou dentro do tecido das
352
glândulas salivares e das adrenais, semelhantemente a reação inflamatória observada no SNC,
353
podem auxiliar no diagnóstico dessa patologia, principalmente nos casos em que não são
354
observadas inclusões no SNC. As glândulas salivares também tem sido um importante órgão
355
para a realização do isolamento viral do Lyssavirus, já tendo sido encontrada positividade
356
para raiva em glândulas salivares avaliadas por outros autores [11].
357
Diferentemente dos herbívoros, onde geralmente as principais lesões são cerebelares,
358
os carnívoros tendem a apresentar lesões mais intensas na região de hipocampo, entretanto, de
15
359
forma semelhante aos bovinos, pode haver áreas com pouca ou ausente reação inflamatória
360
[14]. Um aspecto importante da análise histopatológica é a realização de cortes seriados do
361
sistema nervoso central, uma vez que a localização e intensidade das lesões podem variar
362
entre as regiões do SNC, não havendo uma uniformidade.
363
A forte marcação nos neurônios do hipocampo no presente trabalho através da imuno-
364
histoquímica, difere dos achados de Stein et al. [12] que encontraram uma marcação
365
moderada no hipocampo de raposas da espécie Urocyon cinereoargenteus e Vulpes vulpes.
366
Apesar das implicações legais, muitas pessoas tem o hábito de criar raposas e outros
367
animais silvestres no Nordeste brasileiro. Essa tradição aumenta significativamente o risco de
368
transmissão da raiva para humanos e outros animais. No ano de 2012, duas pessoas morreram
369
no Nordeste vítimas de raiva transmitidas por animais silvestres [13]. No Estado da Paraíba, a
370
raposa tem sido o animal silvestre com maior número de agressões contra humanos, havendo
371
no período de 2000 a 2003, cerca de 24 casos de agressões em humanos por raposas [7].
372
Propõe-se que a ocorrência de raiva em herbívoros nos Estados da Paraíba e
373
Pernambuco é causada principalmente por uma variante do vírus chamada de RABV,
374
relacionada a morcegos hematófagos e que ela está circulante nessa área do Nordeste por pelo
375
menos sete anos, isolada por barreiras geográficas [9]. Sugere-se ainda, a presença de duas
376
ramificações de Lyssavirus na região da Paraíba, sendo uma associada com quirópteros e
377
outra com carnívoros. Entretanto, existe uma variabilidade genética nessas ramificações,
378
subdividindo o grupo de quirópteros em “morcegos insetívoros” e “morcegos hematófagos”, e
379
o grupo dos carnívoros em “cão”, “raposa 1” e “raposa 2” (está mais próxima do grupo “cão”)
380
[7]. Essa existência de variabilidade entre as ramificações das variantes do vírus rábico sugere
381
que pelo menos dois grupos de vírus coexistem na mesma região e apesar de somente a
382
variante de morcegos hematófagos ter sido incriminada como causadora da raiva em
383
herbívoros, a criação de animais silvestres como animais de estimação no Nordeste favorece o
16
384
risco de transmissão da doença para os animais de produção, sugerindo um papel importante
385
das raposas nesse cenário. A presença da variabilidade genética das variantes de raposas,
386
sugerem que estes animais tem um papel muito mais importante na manutenção e
387
disseminação da raiva no Brasil do que antes se pensava, tendo uma implicação de saúde
388
pública significante já que nessa região o monitoramento desses animais é muitas vezes
389
ineficiente ou ausente, e a prática da vacinação de animais silvestres não tem sido empregada
390
no país [2].
391
O diagnóstico da raiva em raposas pode ser realizado pelos achados histopatológicos
392
característicos do SNC, auxiliado pela avaliação dos gânglios nervosos periféricos, glândulas
393
salivares e adrenais que também podem apresentar lesões microscópicas semelhantes. Em
394
adição os exames laboratoriais auxiliares devem ser realizados, como IFD, ICC e IHQ para a
395
confirmação da doença.
396
MANUFACTURERS
397
1
Chemicon International Inc. Temecula, CA, USA.
398
2
Sigma-Aldrich Corp. St. Louis, MO, USA.
399
3
Dako Cytomation. Carpinteria, CA, USA.
400
401
Declaration of interest. The authors report no conflicts of interest. The authors alone are
402
responsible for the content and writing of the paper.
403
REFERENCES
404
1 Araújo F.A.A. 2002. Raiva humana no Brasil: 1992-2001. 90f. Belo Horizonte, MG.
405
Dissertação (Mestrado em Medicina Veterinária) - Programa de Pós-graduação em Medicina
406
Veterinária, Universidade Federal de Minas Gerais.
407
2 Bernardi F., Nadin-Davis S.A., Wandeler A.I., Armstrong J., Gomes, A.A.B., Lima
408
F.S., Nogueira F.R.B. & Ito F.H. 2005. Antigenic and genetic characterization of rabies
17
409
viruses isolated from domestic and wild animals of Brazil identifies the hoary fox as a rabies
410
reservoir. Journal of General Virology. 86(11): 3153-3162.
411
3 Carnieli Jr. P., Brandão, P.E., Carrieri M.L., Castilho J.G., Macedo C.I., Machado
412
L.M., Rangel N., Carvalho R.C., Carvalho V.A., Montebello L., Wada M. & Kotait I.
413
2008. Characterization of rabies virus isolated from canids and identification of the main wild
414
canid host in Northeastern Brazil. Virus Research. 131(1): 33-46.
415
4 Childs J.E. & Real L.A. 2007. Epidemiology. In: Jackson A.C. & Wunner W.H. (Eds).
416
Rabies. San Diego: Academic Press, pp.123-199.
417
5 Dean D.J., Abelseth M.K. & Atanasiu P. 1996. The fluorescent antibody test. In: Meslin
418
F.X., Kaplan M.M. & Koprowski H. (Eds). Laboratory Techniques in Rabies. 4th edn.
419
Geneva: World Health Organization, pp.88-93.
420
6 Gomes A.A.B. 2004. Epidemiologia da raiva: caracterização de vírus isolados de animais
421
domésticos e silvestres do semi-árido paraibano da região de Patos, Nordeste do Brasil. 107f.
422
São Paulo, SP. Tese (Doutorado em Medicina Veterinária) - Programa de Pós-graduação em
423
Epidemiologia Experimental Aplicada às Zoonoses, Universidade de São Paulo.
424
7 Gomes A.A.B., Silva M.L.C.R., Bernardi F., Sakai T., Itou T. & Ito F.H. 2012.
425
Molecular epidemiology of animal rabies in the semiarid region of Paraíba, Northeastern
426
Brazil. Arquivos do Instituto Biológico. 79(4): 611-615.
427
8 Koprowski H. 1996. The mouse inoculation test. In: Meslin F.X., Kaplan M.M. &
428
Koprowski H. (Eds). Laboratory Techniques in Rabies. 4th edn. Geneva: World Health
429
Organization, pp.80-86.
430
9 Mochizuki N., Kawasaki H., Silva M.L.C.R., Afonso J.A.B., Itou T., Fumio H. & Sakai
431
T. 2012. Molecular epidemiology of livestock rabies viruses isolated in the northeastern
432
Brazilian states of Paraíba and Pernambuco from 2003-2009. BMC Research Notes. 5(32): 1-
433
7.
18
434
10 Ramos Jr. V.A., Pessutti C. & Chieregatto C.A.F.S. 2003. Guia de Identificação dos
435
Canídeos Silvestres Brasileiros. Sorocaba: JoyJoy Studio Ltda. - Comunicação Ambiental,
436
35p.
437
11 Silva M.L.C.R, Lima F.S., Gomes A.A.B., Azevedo S.S., Alves C.J., Bernardi F. & Ito
438
F.H. 2009. Isolation of rabies virus from the parotid salivary glands of foxes (Pseudalopex
439
vetulus) from Paraíba State, Northeastern Brazil. Brazilian Journal of Microbiology. 40(3):
440
446-449.
441
12 Stein L.T., Rech R.R., Harrison L. & Brown C.C. 2010. Immunohistochemical study of
442
rabies virus within the central nervous system of domestic and wildlife species. Veterinary
443
Pathology. 47(4): 630-633.
444
13 SVS - Ministério da Saúde. Fundação Nacional de Saúde. 2012. Mapas da Raiva no
445
Brasil. Brasília: Organização Pan-Americana da Saúde; Organização Mundial da Saúde;
446
Ministério da Saúde.
447
14 Zachary J.F. 2009. Sistema Nervoso. In: McGavin M.D. & Zachary J.F. (Eds). Bases da
448
Patologia em Veterinária. 4.ed. Rio de Janeiro: Elsevier, pp.833-971.
449
Tabela 1. Distribuição das lesões no SNC de raposas (Cerdocyon thous) com raiva de acordo
450
com a intensidade da resposta inflamatória e presença de corpúsculos de Negri.
451
Figura 1. Lesões histológicas de raposas (Cerdocyon thous) com raiva. (A) Córtex occipital
452
mostrando manguitos mononucleares perivasculares e corpúsculos de Negri (seta) [HE, 10x].
453
(B) Hipocampo com múltiplos corpúsculos de Negri (setas) [HE, 20x]. (C) Gânglio trigêmeo
454
com infiltrado inflamatório mononuclear [HE, 20x]. (D) Glândula salivar com inflamação não
455
supurativa [HE, 20x].
456
Figura 2. Seções do encéfalo de raposas (Cerdocyon thous) com raiva, submetidas à técnica
457
de imuno-histoquímica. (A) Córtex e (B) Tronco encefálico (ponte) mostrando múltiplos
458
agregados de grânulos amarronzados distribuídos no pericário e prolongamentos
459
citoplasmáticos de neurônios, caracterizando imunomarcação positiva para raiva. (C) Córtex.
460
Controle negativo (sem anticorpo). Técnica de imuno-histoquímica método da estreptavidina-
461
biotina-peroxidase (LSAB+System HRP) contracorados com Hematoxilina de Harris [Barra =
462
20 µm].
19
463
464
CASE REPORT
465
Classical Scrapie Diagnosis in ARR/ARR Sheep in Brazil
466
Juliano Souza Leal1,2, Caroline Pinto de Andrade2, Gabriel Laizola Frainer
467
Correa2, Gisele Silva Boos2, Matheus Viezzer Bianchi2, Sergio Ceroni da
468
Silva2 ,Rui Fernando Felix Lopes3 & David Driemeier2
469
470
471
472
473
474
475
476
477
478
479
1
Programa de Pós-graduação em Ciências Veterinárias (PPGCV), Faculdade de Veterinária
(FaVet), Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
2
Setor de Patologia Veterinária (SPV), Departamento de Patologia Clínica Veterinária
(DPCV), FAVET, UFRGS, Porto Alegre, RS, Brazil. 3Departamento de Ciências
Morfológicas, Instituto de Ciências Básicas da Saúde (ICBS), UFRGS, Porto Alegre, RS.
CORRESPONDENCE: J.S. Leal [[email protected] - Tel.: +55 (51) 3308 3631]. Setor
de Patologia Veterinária, FAVET, UFRGS. Av. Bento Gonçalves n. 9090, Bairro Agronomia.
CEP 91540-000 Porto Alegre, RS, Brazil.
20
480
ABSTRACT
481
Background: Scrapie is a transmissible spongiform encephalopathy (TSE) that affects sheep
482
flocks and goat herds. The transfer of animals or groups of these between sheep farms is
483
associated with increased numbers of infected animals and with the susceptibility or the
484
resistance to natural or classical scrapie form. Although several aspects linked to the etiology
485
of the natural form of this infection remain unclarified, the role of an important genetic
486
control in scrapie incidence has been proposed. Polymorphisms of the PrP gene (prion
487
protein, or simply prion), mainly in codons 136, 154, and 171, have been associated with the
488
risk of scrapie.
489
Case: One animal from a group of 292 sheep was diagnosed positive for scrapie in the
490
municipality of Valparaíso, state of São Paulo, Brazil. The group was part of a flock of 811
491
free-range, mixed-breed Suffolk sheep of the two genders and ages between 2 and 7 years
492
from different Brazilian regions. Blood was collected for genotyping (for codons 136, 141,
493
154 and 171), and the third lid and rectal mucosa were sampled for immunohistochemistry
494
(IHC) for scrapie, from all 292 animals of the group. IHC revealed that seven (2.4%) animals
495
were positive for the disease. Collection of samples was repeated for 90 animals, among
496
which the seven individuals diagnosed positive and 83 other animals that had some degree of
497
kinship with those. These 90 sheep were sacrificed and necropsied, when samples of brain
498
(obex), cerebellum, third eyelid, rectal mucosa, mesenteric lymph node, palatine tonsil, and
499
spleen were collected for IHC. The results of IHC analyses carried out after necropsy of the
500
seven positive animals submitted to the second collection of lymphoreticular tissue and of the
501
83 animals with some degree of kinship with them confirmed the positive diagnosis obtained
502
in the first analysis, and revealed that three other sheep were also positive for scrapie.
503
Samples of 80 animals (89%) were negative for the disease in all organs and tissues analyzed.
504
In turn, 10 sheep (11%) were positive, presenting immunoreactivity in one or more tissues.
20
21
505
Genotyping revealed the presence of four of the five alleles of the PrP gene commonly
506
detected in sheep: ARR, ARQ, VRQ and ARH. These allele combinations formed six
507
haplotypes: ARR/ARR, ARR/ARQ, ARH/ARH, ARQ/ARH, ARQ/ARQ and ARQ/VRQ.
508
Animals were classified according to susceptibility to scrapie, when 8.9% of the genotyped
509
sheep were classified into risk group R1 (more resistant, with no restriction to breeding). In
510
turn, 40% of the animals tested ranked in groups R4 and R5 (genetically very susceptible,
511
cannot be used for breeding purposes).
512
Discussion: The susceptibility of sheep flocks depends on the genetic pattern of animals and
513
is determined by the sequence of the gene that codifies protein PrP. Additionally, numerous
514
prion strains are differentiated based on pathological and biochemical characteristics, and may
515
affect animals differently, depending on each individual’s genotype. Most epidemiologic data
516
published to date indicate that animals that carry the ARR/ARR genotype are less susceptible
517
to classical scrapie. However, in the present study, the fact that two scrapie-positive sheep
518
presented the haplotype ARR/ARR indicates that this genotype cannot always be considered
519
an indicator of resistance to the causal agent of the classical manifestation of the disease. The
520
coexistence in the same environment of several crossbred animals from different flocks and
521
farms, which characterizes a new heterogeneous flock, may have promoted a favorable
522
scenario to spread the disease, infecting animals in the most resistant group.
523
Keywords: biopsy, scrapie, TSEs, immunohistochemistry.
524
Descritores: biopsia, scrapie clássico, EETs, imuno-histoquímica.
525
526
INTRODUCTION
527
Scrapie, also called epizootic tremor, is a transmissible spongiform encephalopathy
528
(TSE) that affects sheep flocks and goat herds [44]. The relocation of animals to and from
529
sheep farms has been associated with increased numbers of infected animals [28,39]. Once it
21
22
530
is introduced in a flock, the disease may be transmitted both vertically, from ewe to lamb, and
531
horizontally, across animals [15,39,49]. Many aspects surrounding the etiology of the natural
532
form of this infection remain to be clarified, though the existence of an important genetic
533
control has been proposed to explain the disease’s incidence [24]. The analysis of the gene
534
PrP (prion protein, or simply prion) in ovine of different breeds has drawn attention to the
535
interaction between host genotype polymorphisms and susceptibility to the infectious agent of
536
scrapie [10,21-23,31].
537
Single nucleotide polymorphisms (SNT) have been linked to susceptibility or
538
resistance to classical scrapie. These polymorphisms occur at codons 136 (A or V, alanine or
539
valine), 154 (R or H, arginine or histidine) and 171 (R, Q or H, arginine, glutamine or
540
histidine) [16]. The diagnosis of the classical form in sheep with haplotype A136R154R171 is
541
rare [24]. Under natural exposure conditions, this genotype (ARR/ARR) has been
542
acknowledged as having the lowest risk for the classical form [16]. This case report describes
543
the occurrence of an outbreak in a flock of mixed Suffolk sheep of varied origins in the state
544
of São Paulo, southeastern Brazil, when the disease was diagnosed in two animals carrying
545
the genotype ARR/ARR, compatible with classical scrapie.
546
547
CASE
548
In 2011, one ovine head from a group of 292 animals was diagnosed with the classical
549
form of scrapie. These sheep were part of a larger flock of 811 free-range animals of both
550
genders and between 2 and 7 years of age that were brought from southern, southeastern and
551
midwestern Brazil. Since the animal died, and diagnosis was carried out after the death, a
552
decision was made to collect blood samples from all 292 animals of the group, for sequencing
553
and genotyping (for codons 136, 141, 154 and 171). In addition, the third eyelid and the rectal
554
mucosa of all 292 animals were biopsied for immunohistochemistry (IHC). After IHC, a new
22
23
555
collection was conducted in 90 animals (approximately 30% of the original group). These
556
included the animals with positive diagnosis in the first collection, and those that had some
557
degree of kinship with scrapie-positive sheep in the original group. These animals were
558
sacrificed and necropsied to collect brain tissue (obex), cerebellum, third eyelid, rectal
559
mucosa, mesenteric lymph node, palatine tonsil, and spleen used in the IHC analyses.
560
Tissue samples were collected and processed for histology and IHC for PrPSc
561
following the methodology proposed by O’Rourke et al. [43]. Rectal biopsy samples were
562
collected and processed according to Espenes et al. [17]. Anti-prion1 monoclonal antibodies
563
F89/160.1.5 and F99/97.6.1 were diluted to a 1:500 solution and added to samples, which
564
were then incubated in a humid chamber at 4ºC for 12 h [34].
565
Blood was collected by punction of the jugular vein using EDTA as anticoagulant and
566
stored at -20ºC for subsequent processing. Genomic DNA of sheep was extracted using 500
567
μL whole blood and the QIAmp™ DNA Blood Kit2 according to the manufacturer’s
568
instructions. PCR was carried out using the DNA sample, 15 pmol each primer, 1X PCR
569
buffer (Tris-HCl pH 8.4, 50 mM KCl)3, MgCl2 1.5 mM, dNTP4 200 μM, and 1U Platinum™
570
enzyme Taq DNA Polymerase3 according to the following cycles: 95ºC for 5 min, 35 cycles
571
at 95ºC for 30 s and at 58ºC for 30 s, and 72ºC for 30 s. PCR was performed using a forward
572
primer flanking the 136 codon position (5’-ATGAAGCATGTGGCAGGAGC-3’) and a
573
reverse primer flanking the 171 codon position (5’-GGTGACTGTGTGTTGCTTGACTG-3’).
574
A 245-bp fragment was generated, which contains the regions of the main codons analyzed
575
for susceptibility to scrapie [36].
576
The PCR product was purified and quantified using the commercial products Purelin5
577
and Qubit5, respectively, following the manufacturers’ instructions. Sequencing was
578
performed with 3 ng DNA and 3.2 pmol each primer, using the BigDye Terminator v.1.1
579
Cycle Sequencing kit6 in the ABI PRISM 3110 Genetic Analyzer6.
23
24
580
581
Of the 292 mixed Suffolk sheep whose lymphoreticular tissues of the third eyelid were
analyzed by IHC, seven (2.4%) were positive for scrapie in the first sample collection.
582
The IHC results of the second samples collected from these seven sheep after necropsy
583
and of the samples collected from the other 83 animals with some degree of kinship with them
584
confirmed the positive diagnosis obtained initially, and revealed that three other animals were
585
also positive for the scrapie. The samples of all organs and tissues of 80 animals (89%) were
586
negative, while those of 10 sheep (11%) were positive, with immunoreactivity in one or more
587
tissues.
588
At least three lymphoid follicles were analyzed by IHC in all samples obtained from
589
necropsied animals. No animal was positive in all samples collected, but different organs and
590
tissues showed immunoreactivity. The third eyelid (Figure 1) and the palatine tonsil were the
591
tissues with the highest percentage of immunoreactive samples (90%, 9/10). The lymphoid
592
tissue of the rectal mucosa (Figure 2) showed immunoreactivity in only one animal (10%,
593
1/10). No immunoreactivity was observed in mesenteric lymph node, spleen and obex
594
samples.
595
Genotyping of codon 141 showed homozygosis for lysine (L141L or L/L) in all 90
596
animals investigated. The genotypes and frequencies of alleles for codons 136, 154 and 171 of
597
these sheep (10 positive and 80 related) are shown in Table 1.
598
Four of the five alleles of the PrP gene commonly detected in ovine were found: ARR,
599
ARQ, VRQ and ARH. The allele AHQ was not detected in any sample. Of the 15
600
possibilities, these allele combinations formed six haplotypes: ARR/ARR, ARR/ARQ,
601
ARH/ARH, ARQ/ARH, ARQ/ARQ and ARQ/VRQ.
602
The haplotype ARR/ARQ was detected in 39 samples (43.3%) and was the most
603
frequent, followed by haplotypes ARQ/ARQ, detected in 34 (37.7%), ARR/ARR, present in
604
eight (8.9%), and ARQ/ARH, observed in five samples (5.6%). Haplotypes ARH/ARH and
24
25
605
ARQ/VRQ were detected in two samples each (2.2%). The classification of animals
606
according to the susceptibility criteria described by Dawson et al. [13] placed 8.9% of the
607
total number of genotyped animals in scrapie risk group R1, which includes more resistant
608
animals that are not subject to reproduction restrictions. A significant percentage of animals
609
(43.3%) was in risk group R2, which requires careful selection for breeding. In addition, 7.8%
610
of animals were in group R3 (intermediate risk), while 40% were in groups R4 and R5 (highly
611
susceptible animals that should not be included in reproduction programs).
612
613
DISCUSSION
614
The susceptibility of sheep flocks to scrapie depends largely on the genetic pattern of
615
the animal, and is determined mainly by the sequence of the gene that codifies the PrP
616
protein, since there are several polymorphisms that affect the conversion of the cell protein
617
PrPC to its pathological form, PrPSc [8,9]. Nevertheless, it is not possible to consider the
618
occurrence of only one form of ovine prion, since there are numerous prion strains with
619
different pathological and biochemical characteristics that may affect animals distinctively,
620
depending on their genotypes [1,30].
621
In the present study, the frequency of codon VRQ was very low (2.2%), confirming
622
previous findings, which revealed that the alleles ARR and ARQ prevail in Suffolk sheep, and
623
that the allele ARH sometimes is detected [12,32]. The high sensitivity of homozygous VRQ
624
carriers or of individuals with ARQ haplotypes has also been reported in the literature [24].
625
This condition raises concerns about susceptibility from the epidemiological perspective,
626
since the allele VRQ, which is rare or absent in breeds like Suffolk, was present in two
627
animals, one of which was positive for scrapie.
628
Most epidemiological and genetic data published indicate that sheep carrying the
629
haplotype ARR/ARR are less susceptible to classical form, while animals with the haplotype
25
26
630
VRQ in homozygosis or with ARQ haplotypes are highly susceptible [24]. This hypothesis is
631
supported by genotyping data for thousands of sheep with the disease around the world. For
632
example, a study carried out in Japan described a classical scrapie case in one ARR/ARR
633
sheep [16]. Sensitivity of ARR/ARR sheep in a scenario of oral exposure to the disease has
634
also been reported [3]. Atypical cases were observed in ARR/ARR animals [11,42].
635
Polymorphisms at codon positions 136, 154 and 171 are not the only ones associated
636
with resistance or susceptibility to scrapie [33]. An analysis of the variation of codon
637
positions 136 and 171, for instance, showed that each has several adjacent polymorphic sites
638
and may codify up to four amino acids [7,50]. The atypical scrapie form, characterized by
639
strain Nor98 [6], is more frequently detected in AHQ animals that carry a polymorphism in
640
codon 141, and has not been described in Suffolk sheep in Brazil [2]. This atypical form
641
expresses phenylalanine (F), instead of leucine (L) in the form L141F [6,37,46].
642
However, although it is generally acceptable that classical scrapie is an infectious and
643
contagious disease [14], contagion with the atypical form is questionable in light of the fact
644
that the specific marker for the atypical manifestation of the disease is detected outside the
645
central nervous system [5,20,29], even in cases experimentally transmitted to transgenic mice
646
[35] and sheep [47]. Several studies have demonstrated that susceptibility to the atypical form
647
is consistently associated with PrP codons 141 (L/F) and 154 (R/H) [6,42]. In fact, studies
648
have proposed the hypothesis that this form may evolve when the animal is not exposed to the
649
infectious agent [5,18,29,48], given the limited knowledge of the physiopathology of this
650
manifestation of the disease [19].
651
In the present study, two (2/8) positive animals presented the haplotype ARR/ARR,
652
which is considered to be the least susceptible and therefore responsible for the lowest risk of
653
scrapie. However, like all sheep that were genotyped, these animals did not present any
654
change in lysine in codon position 141. This change (that is, when lysine is replaced by
26
27
655
phenylalanine) has been associated with atypical scrapie in Suffolk sheep [6]. Therefore, these
656
two ARR/ARR sheep do not fit in the genotypic characteristics of sheep that may commonly
657
present the atypical form. It is possible that the presence of several crossbred animals of
658
different flocks and farms in the same environment, which characterizes an heterogeneous
659
flock, has created the favorable conditions for the disease to evolve and spread, infecting the
660
more susceptible animals.
661
The variation in the frequency of the PrP genotype between flocks has been identified
662
as a real risk factor for the disease [4]. The introduction of adult sheep free of scrapie in
663
contaminated flocks is believed to allow lateral transmission, even between adult animals
664
with less susceptible genotypes [40,45], although young sheep are more predisposed [43].
665
Other reasons behind differences in occurrence include the stress caused during husbandry
666
and large population numbers [26]. Additionally, the lack of a defined epidemiological pattern
667
and the different strains of the causal agent play an important role in inter-flock variability
668
[40]. Several models were based on the assumption that outbreak duration is influenced by
669
flock size and by the frequency of the PrP genotype in one flock [25,26,38,51]. Commercial
670
flocks with high genetic diversity, mainly in codons other than 136, 154 and 171, are more
671
consistently affected. In these animals, the onset of clinical manifestations occurs at
672
significantly different ages, with means varying from 2 to 5.7 years, due to noteworthy
673
dissimilarities in age and PrP genotype profiles [40]. The purchase of infected animals has
674
been pointed out as the main scrapie infection mechanism in flocks [27, 41].
675
676
CONCLUSION
677
The diagnosis of scrapie in two homozygous ARR/ARR sheep indicates that the
678
resistance of this genotype to the classical form of the disease is debatable. Although scrapie
679
in these animals is rare, the cases presented in this case report lend strength to the notion that
27
28
680
its occurrence depends on a combination of infectious factors, including differences in
681
biological and biochemical properties in the natural hosts to this prion.
682
MANUFACTURERS
683
1
DAKO Corp. Carpinteria, CA, USA.
684
2
Qiagen. Hilden, Germany.
685
3
InvitrogenTM, São Paulo, Brazil.
686
4
Life TechnologiesTM. Gaithersburg, MD, USA.
687
5
InvitrogenTM. Carlsbad, CA, USA.
688
6
Applied Biosystems Inc. Foster City, CA, USA.
689
690
Declaration of interest. The authors report no conflicts of interest. The authors alone are
691
responsible for the content and writing of the paper.
692
693
REFERENCES
694
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695
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696
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697
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698
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699
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9 Bossers A., De Vries R. & Smits M.A. 2000. Susceptibility of sheep for scrapie as
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723
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15 Dickinson A.G., Stamp J.T. & Renwick C.C. 1974. Maternal and lateral transmission of
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16 Elsen J.M., Amigues Y., Schelcher F., Ducrocq V., Andreoletti O., Eychenne F.,
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Khang J.V., Poivey J.P., Lantier F. & Laplace J.L. 1999. Genetic susceptibility and
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17 Espenes A., Press C.M.C.L., Landsverk T., Tranulis M.A., Aleksandersen M.,
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743
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18 Fediaevsky A., Morignat E., Ducrot C. & Calavas D. 2009. A case-control study on the
746
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19 Fediaevsky A., Calavas D., Gasqui P., Moazami-Goudarzi K., Laurent P., Arsac J.N.,
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749
French sheep and potential consequences of the current breeding programme for resistance to
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20 Fediaevsky A., Gasqui P., Calavas D. & Ducrot C. 2010. Discrepant epidemiological
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patterns between classical and atypical scrapie in sheep flocks under French TSE control
753
measures. The Veterinary Journal. 185(3): 338-340.
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21 Foster J.D., Wilson M. & Hunter N. 1996. Immunolocalisation of the prion protein (PrP)
755
in the brains of sheep with scrapie. Veterinary Record. 139(21): 512-515.
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22 Goldmann W., Hunter N., Benson G., Foster J.D. & Hope J. 1991. Different scrapie-
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31
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associated fibril proteins (PrP) are encoded by lines of sheep selected for different alleles of
758
the Sip gene. Journal of General Virology. 72(10): 2411-2417.
759
23 Goldmann W., Hunter N., Smith G., Foster J. & Hope J. 1994. PrP genotype and agent
760
effects in scrapie: change in allelic interaction with different isolates of agent in sheep, a
761
natural host of scrapie. Journal of General Virology. 75(5): 989-995.
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24 Groschup M.H., Lacroux C., Buschmann A., Lühken G., Mathey J., Eiden M., Lugan
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S., Hoffmann C., Espinosa J.C., Baron T., Torres J.M., Erhardt G. & Andreoletti O.
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2007. Classic scrapie in sheep with the ARR/ARR prion genotype in Germany and France.
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Emerging Infectious Diseases. 13(8): 1201-1207.
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25 Gubbins S. 2005. A modelling framework to describe the spread of scrapie between sheep
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flocks in Great Britain. Preventive Veterinary Medicine. 67(2-3): 143-155.
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26 Hagenaars T.J., Ferguson N.M., Donnelly C.A. & Anderson R.M. 2001. Persistence
769
patterns of scrapie in a sheep flock. Epidemiology and Infection. 127(1): 157-167.
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27 Healy A.M., Morgan K.L., Hannon D., Collins J.D., Weavers E. & Doherty M.L.
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2004. Postal questionnaire survey of scrapie in sheep flocks in Ireland. Veterinary Record.
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155(16): 493-494.
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28 Hoinville L.J., Hoek A., Gravenor M.B. & McLean A.R. 2000. Descriptive
774
epidemiology of scrapie in Great Britain: results of a postal survey. Veterinary Record.
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146(16): 455-461.
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29 Hopp P., Omer M.K. & Heier B.T. 2006. A case-control study of scrapie Nor98 in
777
Norwegian sheep flocks. Journal of General Virology. 87(12): 3729-3736.
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30 Hunter N., Foster J.D. & Hope J. 1992. Natural scrapie in British sheep: breeds, ages
779
and PrP gene polymorphisms. Veterinary Record. 130(18): 389-392.
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31 Hunter N., Goldmann W., Benson G., Foster J.D. & Hope J. 1993. Swaledale sheep
781
affected by natural scrapie differ significantly in PrP genotype frequencies from healthy sheep
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32
782
and those selected for reduced incidence of scrapie. Journal of General Virology. 74(6):
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1025-1031.
784
32 Hunter N., Cairns D., Foster J.D., Smith G., Goldmann W. & Donnelly K. 1997. Is
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scrapie solely a genetic disease? Nature. 386(6621): 137.
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33 Laegreid W.W., Clawson M.L., Heaton M.P., Green B.T., O'Rourke K.I. & Knowles
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D.P. 2008. Scrapie resistance in ARQ sheep. Journal of Virology. 82(20):10318-10320.
788
34 Leal J.S., Correa G.L.F., Dalto A.G.C., Boos G.S., Oliveira E.C., Bandarra P.M.,
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Lopes R.F.F. & Driemeier D. 2012. Utilização de biopsias da terceira pálpebra e mucosa
790
retal em ovinos para diagnóstico de scrapie em uma propriedade da Região Sul do Brasil.
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35 Le Dur A., Béringue V., Andréoletti O., Reine F., Lai T.L., Baron T., Bratberg B.,
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Vilotte J.L., Sarradin P., Benestad S.L. & Laude H. 2005. A newly identified type of
794
scrapie agent can naturally infect sheep with resistant PrP genotypes. Proceedings of the
795
National Academy of Sciences of the USA. 102(44): 16031-16036.
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36 L'Homme Y., Leboeuf A. & Cameron J. 2008. PrP genotype frequencies of Quebec
797
sheep breeds determined by real-time PCR and molecular beacons. Canadian Journal of
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Veterinary Research. 72(4): 320-324.
799
37 Lühken G., Buschmann A., Groschup M.H. & Erhardt G. 2004. Prion protein allele
800
A136H154Q171 is associated with high susceptibility to scrapie in purebred and crossbred
801
German Merinoland sheep. Archives of Virology. 149(8): 1571-1580.
802
38 Matthews L., Woolhouse M.E.J. & Hunter N. 1999. The basic reproduction number for
803
scrapie. Proceedings of the Royal Society B: Biological Sciences. 266(1423): 1085-1090.
804
39 McIntyre K.M., Gubbins S., Sivam S.K. & Baylis M. 2006. Flock-level risk factors for
805
scrapie in Great Britain: analysis of a 2002 anonymous postal survey. BMC Veterinary
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Research. 2: 25.
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40 McIntyre K.M., Gubbins S., Goldmann W., Hunter N. & Baylis M. 2008.
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Epidemiological characteristics of classical scrapie outbreaks in 30 sheep flocks in the United
809
Kingdom. PLoS One. 3(12): e3994.
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41 McLean A.R., Hoek A., Hoinville L.J. & Gravenor M.B. 1999. Scrapie transmission in
811
Britain: a recipe for a mathematical model. Proceedings of the Royal Society B: Biological
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Sciences. 266(1437): 2531-2538.
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42 Moum T., Olsaker I., Hopp P., Moldal T., Valheim M., Moum T. & Benestad S.L.
814
2005. Polymorphisms at codons 141 and 154 in the ovine prion protein gene are associated
815
with scrapie Nor98 cases. Journal of General Virology. 86(1):231-235.
816
43 O'Rourke K.I., Duncan J.V., Logan J.R., Anderson A.K., Norden D.K., Williams
817
E.S., Combs B.A., Stobart R.H., Moss G.E. & Sutton D.L. 2002. Active surveillance for
818
scrapie by third eyelid biopsy and genetic susceptibility testing of flocks of sheep in
819
Wyoming. Clinical and Diagnostic Laboratory Immunology. 9(5): 966-971.
820
44 Prusiner S.B. 1995.The prion diseases. Scientific American. 272(1): 48-57.
821
45 Ryder S., Dexter G., Bellworthy S. & Tongue S. 2004. Demonstration of lateral
822
transmission of scrapie between sheep kept under natural conditions using lymphoid tissue
823
biopsy. Research in Veterinary Science. 76(3): 211-217.
824
46 Saunders G.C., Cawthraw S., Mountjoy S.J., Hope J. & Windl O. 2006. PrP genotypes
825
of atypical scrapie cases in Great Britain. Journal of General Virology. 87(Pt 11): 3141-3149.
826
47 Simmons M.M., Konold T., Simmons H.A., Spencer Y.I., Lockey R., Spiropoulos J.,
827
Everitt S. & Clifford D. 2007. Experimental transmission of atypical scrapie to sheep. BMC
828
Veterinary Research. 3: 20.
829
48 Simmons H.A., Simmons M.M., Spencer Y.I., Chaplin M.J., Povey G., Davis A.,
830
Ortiz-Pelaez A., Hunter N., Matthews D. & Wrathall A.E. 2009. Atypical scrapie in sheep
831
from a UK research flock which is free from classical scrapie. BMC Veterinary Reserarch. 5:
33
34
832
8.
833
49 Touzeau S., Chase-Topping M.E., Matthews L., Lajous D., Eychenne F., Hunter N.,
834
Foster J.D., Simm G., Elsen J.M. & Woolhouse M.E. 2006. Modelling the spread of
835
scrapie in a sheep flock: evidence for increased transmission during lambing seasons.
836
Archives of Virology. 151(4): 735-751.
837
50 Vaccari G., Conte M., Morelli L., Di Guardo G., Petraroli R. & Agrimi U. 2004.
838
Primer extension assay for prion protein genotype determination in sheep. Molecular and
839
Cellular Probes. 18(1): 33-37.
840
51 Woolhouse M.E., Stringer S.M., Matthews L., Hunter N. & Anderson R.M. 1998.
841
Epidemiology and control of scrapie within a sheep flock. Proceedings of the Royal Society
842
B: Biological Sciences. 265(1402): 1205-1210.
843
FIGURE LEGEND
844
Figure 1. Immunohistochemistry to diagnose scrapie in a histologic section of the third eyelid
845
of a sheep. Lymphoid follicle with immunoreactivity for PrPSc in the germinative center,
846
(arrow head) [magnification: 200x].
847
Figure 2. Immunohistochemistry to diagnose scrapie in a histologic section of the rectal
848
mucosa of a sheep. Lymphoid follicle with immunoreactivity for PrPSc in the germinative
849
center, (arrow head) [magnification: 100x].
850
851
852
853
854
855
856
34
35
857
CASE
858
Sebaceous Adenitis in a Cat
859
Juliane Possebom 1, Marconi Rodrigues de Farias1, Dévaki Liege de Assunção1 & Juliana
860
Werner2
1
861
862
863
864
865
866
867
Mestrado em Ciência Animal (MECA), Escola de Ciência Agrárias e Medicina Veterinária,
Pontifícia Universidade Católica do Paraná (PUCPR), Curitiba, PR, Brazil. 2 Laboratório
Werner & Werner de Patologia Veterinária, Curitiba, PR. CORRESPONDENCE: J.
Possebom [[email protected] - Tel.: +55 (41) 3299-4314]. MECA, Pontifícia
Universidade Católica do Paraná (PUCPR). Br. 376, Km 14. CEP 83010-500 São José dos
Pinhais, PR, Brazil.
868
ABSTRACT
869
Background: Sebaceous adenitis is an inflammatory, dyskeratotic, and chronic disorder,
870
characterized by the degeneration and post-inflammatory atrophy of sebaceous gland, which
871
rarely affects cats. The objective of this paper is to report a case of sebaceous adenitis in a cat,
872
located in the region of Curitiba, Paraná, Brazil.
873
Case: A 12-year-old female cat, crossbreed, with hypotrichosis, alopecia and moderate to
874
intense itching in the dorsal thorax region, limbs and face, which were evolving during a
875
month. Dermatological exams were done, as well as trichogram, fungal culture, sticky-tape
876
test, skin scraping, and parasitological assessments of cerumen, and all of them were normal.
877
Histopathological examination revealed hair follicles at all stages of development, some
878
showing hyperkeratosis with cystic dilation and complete absence of sebaceous glands. In
879
periadnexal region, it showed mild inflammatory infiltrate composed by lymphocytes,
880
histiocytes and neutrophils, which legitimated a definitive diagnosis of sebaceous adenitis.
881
The treatment was made using emollient shampoo, ciclosporin and emollient product based
882
on fatty acids and ceramides, and after one month, the lesions, erythema and pruritus
883
regressed. Due to the clinical improvement, it was possible to keep the animal with
35
36
884
ciclosporin (5.0 mg/kg, p.o, every two days) and Allerderm spot-on (once weekly), obtaining
885
positive results too.
886
Discussion: SA was already described in dogs, cats, rabbits, horses and humans. In cats,
887
diseases involving sebaceous glands are rarely described, and the dermatological changes
888
commonly found includes chronic progressive form with non-itchy scaling, crusting, alopecia
889
and skin depigmentation in regions of the face, cervical and trunk. Considering the case
890
reported, the animal did not present any comorbidity and lesions predominated in the face
891
(auricles, mentonian and perioral region), extending the dorsal midline, thoracic and pelvic
892
limbs. The clinical signs presented were very similar to those described in dogs, with the
893
presence of hypotrichosis, alopecia, follicular cylinders, comedones, scaling and bilateral
894
otitis externa. Pruritus was moderate to intense, even when there was absence of secondary
895
infection, and it is possibly associated with skin and coat xerosis. In the histopathological,
896
acute lesions show granulomatous inflammatory and periadnexal pyogranulomatous reactions
897
around the sebaceous gland, while the chronic lesions may attest the absence of sebaceous
898
gland and focal periadnexal fibrosis. In this case, the findings were periadnexal fibrosis and
899
absence of sebaceous glands were prevailed, which indicates that sebaceous adenitis diagnosis
900
in cat is not been early discovered. Treatment for sebaceous adenitis consists of emollient,
901
moisturizer and humectant therapy associated with supplementation of essential fatty acids,
902
and in the case described, it was also necessary the use of ciclosporin, in order to control the
903
disease. In a preliminary study, the use of ciclosporin in dogs with sebaceous adenitis
904
provided a significantly inflammation reduction and improved clinical status in 60% of the
905
cases. There are evidences that regeneration of sebaceous gland is best achieved with the use
906
of ciclosporin, even when it its administration is isolate or combined with topical therapy.
907
Although it is atypical in cats, sebaceous adenitis must be considered as a differential
908
diagnosis for inflammatory diseases with similar clinical signs.
36
37
909
Keywords: feline, skin, seborrhea, sebaceous glands.
910
911
INTRODUCTION
912
Sebaceous glands are epithelial structures placed at the isthmus region of hair follicles,
913
responsible for producing the lipid emulsion, which had the function of hydrate and protect
914
the surface of the skin and coat, helping to maintain skin softness and hair’s flexibility [2].
915
Sebaceous adenitis (SA) is a disease with a chronic inflammatory disposition that affects
916
sebaceous glands, likewise the synthesis and composition of lipid emulsion secreted.
917
Consequently, skin and coat dryness will occur [15]. Although it has idiopathic origin, in
918
standard poodles and akitas, sebaceous adenitis can be inherited through an autosomal
919
recessive gene with variable expression [9,13]. A hypothesis for its etiopathogeny is the one
920
that describes a keratinisation disorder in which modifies sebaceous composition, obstructing
921
the ducts and triggering the inflammatory process or consider the possibility of an
922
autoimmune response against antigens sited in glands and ducts, stimulating inflammation
923
and conducing to its destruction [7,12]. Xerosis, scaling, silvery scales that adheres to the coat
924
and skin, follicular cylinders and comedones are the characteristics of SA. Follicular
925
hyperkeratosis has been associated with alopecia, folliculitis, furunculosis [13]. Animals
926
affected with SA are predisposed to develop bacterial infections and secondary Malassezia
927
sp., which contributes to the appearance of pruritus [9].
928
Considering the fact that this infection is rarely describe in feline species, this case
929
report has the objective to present the clinical, dermatological and therapeutic aspects of
930
sebaceous adenitis in a cat.
931
932
933
37
38
934
CASE
935
A 12-year-old female cat (crossbreed) with a clinical history based on hypotrichosis
936
and alopecia, associated with moderate to intense pruritus in the dorsal thorax region, limbs
937
and face, which were evolving during a month.
938
The dermatological exam has demonstrated bilateral otitis externa, hypotrichosis and
939
alopecia, xerosis, multiple psoriasiform scales and cerato-sebaceous sediment adhered to skin
940
and coat in in the dorsal thorax region, plus thoracic and pelvic limbs (Figure 1). In the
941
eyelids, mentonian and perioral region was observed erythema, scaling, hypotrichosis,
942
follicular cylinders and comedones (Figures 2a and 2b).
943
Trichogram, fungal culture, sticky-tape test, skin scraping in order to search for
944
parasites, parasitological assessments of cerumen and FIV/FeLV testing presented negative
945
results.
946
Histopathological examination of skin samples has shown epidermis with laminar
947
orthokeratosis and dilatation of some follicular ostia lead by infundibular hyperkeratosis. In
948
the superficial dermis, there was edema and monomorphonuclear inflammatory infiltrate in
949
perivascular pattern. The hair follicles appeared active and in all stages of development, some
950
exhibiting hyperkeratosis and cystic dilation. There was a complete absence of sebaceous
951
glands. In periadnexal region, it showed inflammatory infiltrate composed of lymphocytes,
952
histiocytes and neutrophils. Histopathological findings legitimated a definitive diagnosis of
953
sebaceous adenitis (Figure 3).
954
Treatment was established following the forward description: emollient shampoo
955
(once weekly; Hypoallergenic Vetriderm1), ciclosporin (5.0 mg/kg p.o, once daily), and
956
emollient product based on fatty acids and ceramides (once weekly; Allerderm spot-on2) with
957
regression of lesions, erythema and pruritus after a month of treatment (Figure 4). Later on,
958
after three months of treatment, there was new hair growth in areas of injury and total
38
39
959
reduction of scaling and follicular cylinders. It was applied the medication on alternate days
960
and Allerderm spot-on was maintained once weekly. Due to the clinical improvement, it was
961
possible to keep the animal with ciclosporin (5.0 mg/kg, p.o, every two days) and Allerderm
962
spot-on (once weekly), obtaining positive results too.
963
964
DISCUSSION
SA is an inflammatory disease of sebaceous glands which mainly affects dogs [3],
965
however it was already described in cats [1,11], rabbits [16], horses [8], and humans [6,10].
966
In dogs, the dermatological changes commonly found in this condition includes tegument
967
dyskeratosis with psoriasiform and ptiriasiform scaling, comedones, alopecia and
968
hypotrichosis, follicular cylinders and dry hair [3]. In rabbits, sebaceous adenitis appears as a
969
progressive and chronic process of non-itchy scaling in the face and cervical region, evolving
970
to a generalized exfoliative dermatitis with alopecia and leucoderma [16]. In relation to
971
horses, there are reports that this disease manifests in the form of non-itchy patches with
972
scaling crusts, alopecia and leukoderma in periocular, nasal bridge e nostril areas, and it
973
becomes generalized throughout the years [8].
974
In relation to cats, diseases involving sebaceous glands are rarely described. In a study
975
of 2012, ten cats received a diagnosis of dysplasia of the sebaceous gland, and nine of them
976
were kittens [17]. Few cases of sebaceous adenitis in cats were reported, and on those animals
977
the disease was manifested in a chronic progressive form with non-itchy scaling, crusting,
978
alopecia and skin depigmentation in regions of the face, cervical and trunk [1,11].
979
Histopathology revealed pyogranulomatous perifoliculitis with no sebaceous glands and
980
ortocheratosis [11].
981
Considering the case reported, the animal did not present any comorbidity and lesions
982
predominated in the face (auricles, mentonian and perioral region), extending the dorsal
983
midline, thoracic and pelvic limbs. The clinical signs presented were very similar to those
39
40
984
described in dogs, with the presence of hypotrichosis, alopecia, follicular cylinders,
985
comedones, scaling and bilateral otitis externa [16]. Pruritus was moderate to heavy, even
986
when there was absence of secondary infection, and it is possibly associated with skin and
987
coat xerosis [12].
988
In this research, histopathological findings were similar to those described in dogs [4,
989
12]. Acute lesions show granulomatous inflammatory and periadnexal pyogranulomatous
990
reactions around the sebaceous gland, while the more chronic lesions may attest the absence
991
of sebaceous gland and focal periadnexal fibrosis [8,13] In the present study, periadnexal
992
fibrosis and absence of sebaceous glands were prevailed, which indicates that sebaceous
993
adenitis diagnosis in cat is not been early discovered.
994
SA is usually unresponsive to treatment with anti-inflammatory doses of
995
glycocorticoids [1]. Treatment for sebaceous adenitis consists of emollient, moisturizer and
996
humectant therapy associated with supplementation of essential fatty acids, and in the case
997
described, it was also necessary the use of ciclosporin (5 mg/kg/BID), in order to control the
998
disease. Ciclosporin has shown efficacy on treatment of sebaceous adenitis in doses of 5.0 to
999
10 mg/Kg [5]. In a preliminary study, the use of ciclosporin in dogs with sebaceous adenitis
1000
provided a significantly inflammation reduction and improved clinical status in 60% of the
1001
cases [5]. There are evidences that regeneration of sebaceous gland is best achieved with the
1002
use of ciclosporin, even when it its administration is isolate or combined with topical therapy
1003
[5]. Disorders of the digestive tract are the most common side effects in cats, like vomiting
1004
and diarrhea [14]. There are also reports of anorexia, sneezing, lethargy, and weight loss [14],
1005
symptoms which has no occurrence on this study.
1006
MANUFACTURERS
1007
1
Bayer S.A. São Paulo, SP, Brazil.
1008
2
Virbac. Fort Worth, TX, USA.
1009
40
41
1010
Declaration of interest. The authors report no conflicts of interest. The authors alone are
1011
responsible for the content and writing of the paper.
1012
1013
1014
1015
REFERENCES
1 Baer K., Shoulberg N. & Helton K. 1993. Sebaceous adenitis-like skin disease in two cats.
Veterinary Pathology. 30(5): 437-438.
1016
2 Farias M.R., Peres J.A., Fabris V.E., Costa F.S. & Pinto R.G. 2000. Adenite sebácea
1017
granulomatosa em cães da raça akita relacionados. Clínica Veterinária. 25: 33-38.
1018
3 Frazer M.M., Schick A.E., Lewis T.P. & Jazic E. 2011. Sebaceous adenitis in Havanese dogs: a
1019
retrospective study of the clinical presentation and incidence. Veterinary Dermatology. 22: 267-
1020
274.
1021
4 Gross T.L., Ihrke P.J., Walder E.L. & Affolter V.K. 2005. Diseases of the epidermis. In: Skin
1022
Diseases of the dog and cat: clinical and histopathologic dignosis. 2nd edn. Oxford: Blackwell
1023
Science Lt., pp.186-188.
1024
5 Lortz J., Favrot C., Mecklenburg L., Nett C., Rufenacht S., Seewald W. & Linek M. 2010. A
1025
multicentre placebo-controlled clinical trial on the efficacy of oral ciclosporin A in the treatment
1026
of canine idiopathic sebaceous adenitis in comparison with conventional topical treatment.
1027
Veterinary Dermatology. 21: 593-601.
1028
1029
1030
1031
1032
1033
6 Martins C., Tellechea O., Mariano A. & Baptista P. 1997. Sebaceous adenitis. Journal of the
American Academy Dermatology. 36: 845-846.
7 Obladen A., Farias F., Choque K.C.C., Werner J. & Tammenhain B. 2007. Adenite sebácea em
um cão da raça lhasa apso. Acta Scientiae Veterinariae. 35(Supl 2): 448-449.
8 Osborne C. 2006. Sebaceous adenitis in a 7-year-old Arabian gelding. The Canadian Veterinary
Journal. 47: 583-586.
1034
9 Reichler I.M., Hauser B., Schiller I., Dunstan R. W., Credille K.M., Binder H., Glaus T. &
1035
Arnold S. 2001. Sebaceous adenitis in the Akita: clinical observations, histopathology and
1036
heredity. Veterinary Dermatology. 12: 243-253
41
42
1037
1038
1039
1040
1041
10 Renfro L., Kopf A.W., Gutterman A., Gottlieb G.J. & Jacobson M. 1993. Neutrophilic
sebaceous adenitis. Archives of Dermatology. 129: 910-911.
11 Scott D.N. 1989. Adenite sebacee pyogranulomateuse sterile chez un chat. Point Vétérinaire. 21:
107-111.
12 Simpson
A.
&
McKay
L.
2012.
Sebaceous
adenitis
in
dogs.
[Fonte:
1042
<https://s3.amazonaws.com/assets.prod.vetlearn.com/ba/145e0007dd11e29e50005056ad4736/file
1043
/PV1012_McKay_CE-AD.pdf>].
1044
1045
13 Sousa C.A. 2006. Sebaceous adenitis. Veterinary Clinics of North American: Small Animal
Practice. 36(1): 243-249.
1046
14 Steffan J., Roberts E., Cannon A., Prélaud P., Forsythe P., Fontaine J., King S. & Seewald
1047
W. 2013. Dose tapering for ciclosporin in cats with nonflea-induced hypersensitivity dermatitis.
1048
Veterinary Dermatology. 24: 315-e70.
1049
1050
15 Tevell E.H., Bergvall K. & Egenvall A. 2008. Sebaceous adenitis in Swedish dogs, a
retrospective study of 104 cases. Acta Veterinaria Scandinavica. 50: 11.
1051
16 White S.D., Linder K.E., Schultheiss P., Scott K.V., Garnett P., Taylor M., Best S.J., Walder
1052
E.J., Rosenkrantz W. & Yaeger J.A. 2000. Sebaceous adenitis in four domestic rabbits
1053
(Oryctatagus cuniculus). Veterinary Dermatology. 11: 53-60.
1054
17 Yager J.A., Gross T.L., Shearer D., Rothstein E., Power H., Sinke J.D., Kraus H., Gram D.,
1055
Cowper E., Foster A. & Welle M. 2012. Abnormal sebaceous gland differentiation in 10 kittens
1056
(‘sebaceous gland dysplasia’) associated with generalized hypotrichosis and scaling. Veterinary
1057
Dermatology. 23: 136-e30.
1058
1059
1060
1061
1062
1063
1064
1065
1066
Legendas
Figure 1. A 12-year-old female cat with sebaceous adenitis. Xerosis, scaling and cerato-sebaceous sediment in the dorsal
thorax region.
Figure 2. A 12-year-old female cat with sebaceous adenitis. Eyelids with hypotrichosis and multiple follicular cylinders (a).
Perioral region with scaling, hypotrichosis, follicular cylinders and comedones (b).
Figure 3. Skin. A twelve year old female cat with sebaceous adenitis. Higher magnification of site of sebaceous gland with
histicytes, limphocytes and neutrophils (HE, 40x).
Figure 4. A twelve year old female cat with sebaceous adenitis. Pictur after treatment with ciclosporin, emollient shampoo
and Allerderm spot on®. It is possible absence of xerosis, scaling and cerato-sebaceous sediment in the dorsal thorax region.
1067
42
43
1068
1069
1070
1071
1072
1073
João Pedro Scussel Feranti1, Anelise Bonilla Trindade2, Marília Teresa de Oliveira3,
1074
Fernando Wiecheteck de Souza3, Luis Felipe Dutra Corrêa3, Fabíola Dalmolin3, Arícia
1075
Gomes Sprada3 & Maurício Veloso Brun4
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
CASE
Rigid Endoscopy to Aid the Treatment of Cervical Mucocele in a Dog
1
Mestrado, Programa de pós-graduação em Medicina Veterinária (PPGMV), Universidade
Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil. 2Doutorado, PPGCV, UFRGS,
Porto Alegre, RS, Brazil. 3Doutorado, PPGMV, UFSM, Santa Maria. 4PPPGMV, UFSM,
Santa Maria. CORRESPONDENCE: M.V. Brun [[email protected] - Tel.:
+55(54)9962-7707]. Av. Roraima n. 1000, Cidade Universitária, Bairro Camobi. CEP 97105900 Santa Maria, RS, Brazil.
ABSTRACT
Background: Sialocele or salivary mucocele is the accumulation of saliva in the glandular
1087
connective tissue due to a leakage from damaged salivary duct, which is surrounded by
1088
granulation tissue. The mucocele can be classified according to its location (cervical,
1089
pharyngeal or sublingual, the latter being known as ranula). The treatment consists of salivary
1090
gland and duct excision. However, in some cases, the definition of which side is affected is a
1091
challenge for surgeons. Keeping this in view, the aim of the present study was to describe the
1092
use of rigid endoscopy to determine the affected gland in a dog with cervical mucocele.
1093
Case: A five-year-old Dachshund, weighting 8.2 kg, was presenting progressive swelling in
1094
the ventral cervical area. The animal presented apathy, appetite loss and saliva drooling. A
1095
fluctuant, non-painful, fluid filled mass was noted on physical examination. Sialocele was
1096
diagnosed and surgery was undertaken to excise the involved gland and mass. The patient was
1097
positioned in dorsal recumbence. A skin incision was performed in the cranial-ventral aspect
1098
of the mass as it was not possible to precise the affected side. Following drainage of the
1099
content, the inner aspect of the sialocele capsule was digitally palpated using the surgeon’s
1100
index finger. However, it was still not possible to determinate the affected side. A purse-string
43
44
1101
suture was performed around the incision and a 10 mm cannula was inserted into the sialocele
1102
lumen. The cavity was insufflated with CO2, then using a 0º 10 mm endoscope, the whole
1103
extension of the capsule was inspected. On the right side, the wall was round shaped,
1104
suggesting the presence of the right gland compressing the wall of the affected gland to the
1105
left. On the left side, there were some recesses and irregular surfaces, and an orifice was
1106
identified, suggesting the presence of the ducts opening. Therefore, the left sublingual and
1107
mandibular glands were excised conventionally. The procedure lasted 150 min and it was
1108
performed uneventfully. The patient was followed-up for seven days and skin sutures were
1109
removed after complete primary intention healing. Thirty days postoperative the patient
1110
presented no signs of recurrence.
1111
Discussion: Although several maneuvers were performed in order to diagnose the affected
1112
side in the current report, some doubt remained. Thus, endoscopic diagnosis was tested,
1113
which has not been reported for that purpose in the author’s knowledge. Although not
1114
completely conclusive, such examination provided strong basis that the left side was affected.
1115
A month after the treatment, recurrence did not occur, which is usually one of the most
1116
common complications. Therefore, the exam purposed in this report fulfilled its expectancies,
1117
suggesting that rigid endoscopy may be used as a new tool for identification of which side and
1118
gland are involved in complicated extensive salivary mucoceles cases. Another important
1119
aspect of the procedure was the insufflation of the mucocele cavity that allowed the inner
1120
capsule inspection and did not result in subcutaneous emphysema. It was applied a pressure of
1121
15 mmHg, higher than routinely used for laparoscopy in dogs, since it is a limited region, and
1122
presents reduced risk of subcutaneous absorption or alteration by compression. In conclusion,
1123
endoscopic view of the sialocele inner capsule is feasible in dogs as an adjunct for diagnosing
1124
the affected side in complicated cases.
1125
Keywords: videosurgery, tumor, canine.
44
45
1126
1127
INTRODUCTION
1128
Sialocele, also known as salivary mucocele, consists of saliva collection surrounded
1129
by granulation tissue [1,2,4]. The saliva leaks from damaged salivary gland or duct causing
1130
inflammation in the tissue. The majority of cases occur by trauma, but some are idiopathic,
1131
and the diagnosis is based on history, clinical signs and pathological findings [6]. Mucocele
1132
can be denominated according to its location (cervical, pharyngeal or sublingual/ranula) [5
1133
1134
Treatment consists of gland and duct removal. The complications associated include
1135
seroma, infection, bleeding and recurrence. The recurrence occurs in less than 5% of the
1136
patients and is related with incomplete resection of the gland, erroneous resection of the
1137
unaffected gland or the lymph node instead of the gland [2,6].
1138
The diagnosis may be reached using several noninvasive imaging methods such as
1139
radiography or ultrasound. However, the gold diagnostic method is provided by computed
1140
tomography and/or magnetic resonance imaging, along with cytology, which, in most cases,
1141
reveals a viscous fluid, straw-colored and mucin content [3]. Considering that the diagnosis of
1142
the affected side can be difficult in some cases, the present study describes the use of rigid
1143
endoscopy for this purpose, in a canine presenting cervical mucocele.
1144
CASE
1145
A five-year-old dachshund dog, 8.2 kg, presenting a mass in the ventral cervical
1146
region, was referred to the veterinary hospital. According to the dog’s owner, the enlargement
1147
of the cervical region had first appeared approximately a month ago and became more evident
1148
two days prior the consultation. The patient was lethargic, with appetite loss and saliva
1149
drooling. On clinical examination, a non-painful, fluid filled, fluctuant mass was observed.
45
46
1150
Based on the clinical presentation, it was diagnosed sialocele and surgical treatment was
1151
indicated.
1152
The patient was placed in dorsal recumbence to determine the affected side, but it was
1153
not possible. Then, an incision was made in the cranial-ventral aspect of the mass and the
1154
surgeon did digital palpation of the inner sialocele capsule surface. However, this maneuver
1155
also did not allow determining precisely which glands were affected. Thus, it was considered
1156
the use of endoscopy for this purpose. A purse-string suture was performed around the
1157
incision and a 10 mm cannula was inserted. The sialocele cavity was insufflated with CO2 at
1158
15 mm/Hg pressure. Using a 10 mm/0º rigid endoscope the mucocele capsule was completely
1159
visualized. It was found that the right side toward the correspondent mandibular gland the
1160
wall was rounded. On the left side, there were several recesses and the surface was irregular
1161
and it was possible to visualize an orifice, probably the ducts opening, and a tunnel. These
1162
findings suggested that the left mandibular and sublingual glands were damaged and their
1163
removal was performed by conventional surgery.
1164
In the dead space formed upon the sialocele excision a closed and active drain attached
1165
to a 10 mL syringe was placed. The adenectomy were performed following the technique
1166
previously described by Fossum et al. [1]. Postoperative therapy consisted of cefalexin
1167
(Keflex®1 - 30mg kg-1, TID, orally) for seven days, flunixin meglumine2 (Banamine® - 1.1
1168
mg kg-1, SID, s.c.) for three days and daily cleaning of wounds with NaCl 0.9% until
1169
complete healing.
1170
Procedure lasted 150 min, uneventfully. The patient was monitored for a period of
1171
seven days. At the seventh day, the skin presented good healing by first intention and sutures
1172
were removed. The drain placed in the adenectomy region was removed after 48 h by the dog
1173
itself, even with protective collar and bandages. However, there was no complication
46
47
1174
associated to the event. Thirty days after the surgery, the dog presented no signs of
1175
recurrence.
1176
DISCUSSION
1177
Regarding to the determination of the affected side, an important stage in the treatment
1178
of sialocele, Fossum et al. [1] claim that its definition is possible from positioning the patient
1179
in dorsal decubitus, once the swelling tends to move to the region where the alteration
1180
originated. When this maneuver is insufficient, the authors suggest performing a small
1181
incision in the sialocele and digital palpation of the mucocele’s lumen. On the affected side,
1182
normally, it is possible to find a tract towards the leakage. In this case, although both
1183
maneuvers were performed the affected glands remained unclear. The authors decided to use
1184
the endoscopic to establish the affected region correctly. In the authors’ knowledge, this
1185
attempt has not been reported. The use of endoscopic was not completely conclusive,
1186
although it demonstrated strong indication that the left side was the sialocele location due to
1187
the marked differences of the right side.
1188
It is worth note that the use of CO2 to inflate the cavity improved the visualization of
1189
the capsule’s lumen and it did not cause subcutaneous emphysema. The authors suggest that
1190
the fibrous tissue prevented the gas dissipation into the subcutaneous tissue. It was applied 15
1191
mmHg of pressure, higher than routinely used in laparoscopic surgery in dogs, since the
1192
insufflation was limited to a specific region, with reduced risk of subcutaneous absorption or
1193
compressive alterations.
1194
It is concluded that endoscopic visualization of sialocele internal capsule may be
1195
performed in dogs using the technique described to assist in defining the side where the
1196
affection originated.
1197
1198
MANUFACTURERS
47
48
1199
1
Eli Lilly. São Paulo, SP, Brazil.
1200
2
Schering Plough. São Paulo, SP, Brazil.
1201
1202
Declaration of interest. The authors report no conflicts of interest. The authors alone are
1203
responsible for the content and writing of the paper.
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
REFERENCES
1 Fossum T.W., Hedlund D.A. & Hulse D.A. 2002. Cirurgia do sistema digestório. In:
Fossum T.W. (Ed). Cirurgia de Pequenos Animais. São Paulo: Roca, pp.251-256.
2 Ritter M.J. & Stanley B.J. 2012. Salivary glands. In: Tobias K.M. & Johnston S.A. (Eds).
Veterinary Surgery Small Animals. St. Louis: Saunders-Elsevier, pp.1439-1447.
3 Slatter D. & Basher T. 2003. Orbit. In: Slatter D. (Ed). Textbook of Small Animal
Surgery. 4th edn. Philadelphia: WB Saunders, pp.1430-1442.
4 Smith M.M. 2010. Surgery for cervical, sublingual and pharyngeal mucocele. Journal of
Veterinary Dentistry. 27: 268-273.
5 Sturgess C.P. 2001. Doenças do Trato Alimentar. In: Dunn J.K. (Ed). Tratado de
Medicina de Pequenos Animais. São Paulo: Roca, pp.367-443.
1216
6 Tsioli V., Papazoglou L.G., Basdani E., Kosmas P., Brellou G., Poutahidis T. &
1217
Bagias S. 2013. Surgical management of recurrent cervical sialoceles in four dogs. Journal
1218
of Small Animal Practice. 54(6): 331-333.
1219
1220
LEGENDA
1221
Figure 1. Five-year-old dachshund dog 8.2 kg. (A) Enlargement of the ventral cervical region
1222
(Arrow). (B) 0º/10mm Endoscope inserted into the subcutaneous after insufflations with
1223
medicinal CO2 at a pressure of 15 mm/Hg pressure.
1224
48
49
1225
1226
CASE
1227
1228
Ureterolitíase por oxalato de cálcio em gato
1229
Calcium Oxalate Ureterolithiasis in a Cat
1230
1231
Camila de Oliveira Pereira1, Fernanda Vieira Amorim da Costa2, Andréia Zechin Bavaresco3
1232
& Aline Silva Gouvêa4
1233
1234
1235
1236
1237
1238
1239
1240
1
M.V. Autônoma, Mais Gatos Clínica de Felinos, Porto Alegre, RS, Brazil. 2Departamento de
Medicina Animal (DMA), Universidade Federal do Rio Grande do Sul (UFRGS), Porto
Alegre. 3M.V. Autônoma, Caxias do Sul, RS. 4Doutorado, Programa de Pós-graduação em
Ciências Veterinárias (PPGCV), UFRGS, Porto Alegre. CORRESPONDENCE: C.P. Oliveira
[[email protected] - Tel.: +55 (51) 3588-4110]. Rua Ida Joana Roth n° 57, Bairro
Rio Branco. CEP 93040-600 São Leopoldo, RS, Brazil.
1241
ABSTRACT
1242
Background: Uroliths in ureters are seldom seen in cats and, according to our knowledge,
1243
there are no reports of ureterolithiasis in this specie in our country. The radiography and
1244
ultrasound should be used in combination to improve the sensitivity to 90% in detecting
1245
ureteral calculi in cats. The aim of this study is to report a case of ureterolithiasis in a cat,
1246
emphasizing the importance of appropriate use of diagnostic imaging to identify the cause of
1247
nephropathy, enabling the return of the renal function.
1248
Case: A 7-year-old female cat, was referred to the Veterinary Teaching Hospital of the
1249
Federal University of Rio Grande do Sul with history of weight loss for two months and
1250
previous diagnosis of chronic kidney insufficiency. In blood work, it was found total calcium
1251
and creatinine increase. At x-ray evaluation, it was found two radiopaques structures on the
1252
right kidney, consistent with uroliths and the presence of a small radiopaque structure in the
1253
region of the left ureter. Ultrasound exam indicated two hyperechoic structures in the right
49
50
1254
renal pelvis, forming acoustic shadowing suggestive of lithiasis. The left kidney showed
1255
partial loss of renal parenchyma by distention of the pelvis for anechogenic homogeneous
1256
content compatible with hydronephrosis. It was also observed dilated left ureter in its
1257
proximal third. After three days, the animal was subjected to ureterotomy. After midline
1258
incision of the ventral abdomen, the location of ureteral calculi was identified by inspection
1259
and palpation of the ureter. The ureter was carefully lifted into paralumbar space.
1260
Subsequently, the region where the calculi was located was gently dissected of periureteral fat
1261
and opened through a small longitudinal incision on the calculi. This was removed using a
1262
fine forceps. Subsequently, the calculi was submitted for analyze at Minnesota Urolith Center,
1263
University of Minnesota, USA, confirming its constitution of 100% calcium oxalate. Five
1264
days after surgery, the patient had normal levels of creatinine. Eighteen days after surgery the
1265
patient did another abdominal ultrasound and there was no dilatation of the left renal pelvis
1266
and proximal ureter.
1267
Discussion: Hypercalcemia is a risk factor for formation of calcium oxalate uroliths.
1268
Therefore, their presence should be investigated in azotemic and/ or hypercalcemic animals,
1269
as shown in this study. Due to the radiopacity of calcium oxalate uroliths, they usually are
1270
seen on abdominal radiography. However, due to the reduced size of the ureter and the
1271
overlapping of adjacent structures, sometimes the ureterolithis are not visualized on
1272
radiographs, resulting in low sensitivity. In contrast, ultrasound was found to have a very high
1273
sensitivity in detecting ureteral obstruction, due to the early onset of hydronephrosis and renal
1274
pelvic dilatation in most animals. Thus, due to the complementarity of the two techniques
1275
mentioned above, the x-ray and abdominal ultrasound should be used in combination so there
1276
is 90% of sensitivity in the diagnosis of ureteral lithiasis in cats. Although chronic kidney
1277
disease is a common condition in cats, there are several other causes of azotemia. Many of
1278
these are reversible and the full return of renal function depends on many occasions on the
50
51
1279
fast and correct diagnosis of the cause that leads to impairment of the kidneys. Thus, the
1280
complementarity between the imaging methods should be employed in order to identify the
1281
cause of nephropathy.
1282
Keywords: ureterolith, calculi, feline.
1283
Descritores: ureterólito, cálculo, felino.
1284
INTRODUÇÃO
1285
Aproximadamente 98% dos cálculos localizados nos ureteres de gatos contêm oxalato
1286
de cálcio [5]. No entanto, menos de 7% dos urólitos de oxalato de cálcio encontram-se nos
1287
ureteres desta espécie [7]. Gatos com ureterolitíase podem apresentar vômito, inatividade,
1288
depressão e dor abdominal. Se houver obstrução ureteral, o animal pode desenvolver azotemia
1289
devido à redução aguda ou gradual da função renal [8]. A realização de exames
1290
complementares como a radiografia e a ultrassonografia abdominais é recomendada para
1291
alcançar o correto diagnóstico e a exata localização do urólito [2]. A remoção cirúrgica é
1292
indicada caso haja obstrução, dor, aumento no tamanho e no número de urólitos [3]. O
1293
presente trabalho visa relatar a ocorrência de um urólito de oxalato de cálcio localizado no
1294
ureter de um gato, enfatizando a importância do diagnóstico por imagem para instituição do
1295
tratamento adequado e a resolução da insuficiência renal.
1296
CASO
1297
Um gato, fêmea, sem raça definida, de sete anos de idade, foi encaminhado para o
1298
Serviço de Clínica Médica de Felinos Domésticos do Hospital de Clínicas Veterinárias (HCV)
1299
da UFRGS com histórico de emagrecimento há dois meses. A tutora relatou diagnóstico
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anterior de insuficiência renal crônica. No exame clínico foi verificada desidratação moderada
1301
e escore corporal 4/9. Nos exames complementares, não houve alteração no hemograma nem
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na pressão arterial sistólica. Houve aumento da creatinina 2,52 mg/dL (0,8 - 1,8 mg/dL) e
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cálcio sérico total 12,02 mg/dL (6,2 - 10,2 mg/dL). O potássio e o fósforo estavam dentro dos
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níveis de referência. Na urinálise, a urina apresentou pH 5,5, proteinúria, bacteriúria e
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densidade 1.030. Na radiografia abdominal, foram identificadas duas estruturas radiopacas em
1306
rim direito, compatíveis com urólitos. A terapia instituída inicialmente foi baseada no
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aumento da fonte de hidratação (fluidoterapia subcutânea com ringer com lactato três vezes
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por semana e ração úmida) e alimento com restrição moderada de sódio e fósforo. Após nove
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dias, o animal foi reavaliado e devido aos resultados dos exames anteriores, foi solicitada a
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realização de urocultura, teste de sensibilidade a antimicrobianos e ultrassonografia
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abdominal. Houve crescimento de Escherichia coli (> 104 UFC/mL) e por esta razão iniciou-
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se antibioticoterapia com enrofloxacina (Flotril®)1, na dose de 5 mg/kg por via oral a cada
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vinte e quatro horas. Ao exame ultrassonográfico, observaram-se duas estruturas
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hiperecogênicas arredondadas em pelve renal direita, ambas medindo aproximadamente 0,3
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cm, formadoras de sombreamento acústico, sugestivo de litíase. O rim esquerdo apresentou
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perda parcial do parênquima renal por distensão da pelve por conteúdo anecogênico
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homogêneo compatível com hidronefrose. A pelve mediu 1,2 cm. Observou-se ainda, ureter
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esquerdo dilatado em seu terço proximal, medindo em torno de 0,4 cm de diâmetro. Não foi
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possível acompanhar sua continuidade, bem como sua inserção na bexiga (imagem
1320
compatível com processo obstrutivo). Uma nova radiografia abdominal, nas projeções
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laterolateral (Figura 1A) e ventrodorsal (Figura 1B), revelou a presença de uma pequena
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estrutura radiopaca em região de ureter esquerdo, confirmando a presença de ureterolitíase;
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além dos dois cálculos previamente diagnosticados em pelve renal direita. Foi prescrito
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cloridrato de tramadol (Dorless V®)2, na dose de 1,0 mg/kg por via oral a cada 12 h para
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analgesia e citrato de potássio3 na dose de 50 mg/kg por via oral a cada 12 h devido à
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hipercalcemia. Após três dias, o animal foi submetido à ureterotomia. Após a incisão na linha
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média ventral do abdome, a localização do cálculo ureteral foi identificada por inspeção e
1328
palpação do ureter. O ureter foi elevado cuidadosamente para o espaço paralombar.
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Posteriormente, a região do ureter onde o cálculo estava localizado foi dissecada
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delicadamente da gordura periureteral e foi realizada a abertura do ureter através de uma
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pequena incisão longitudinal sobre o cálculo. Este foi removido utilizando uma pinça fina e as
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extremidades ureterais foram lavadas com soro fisiológico aquecido. Em seguida foi realizada
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sutura com vicryl 5-0, em padrão simples interrompido. Posteriormente, o cálculo foi enviado
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para análise no Minnesota Urolith Center, na Universidade de Minnesota, EUA, confirmando
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a sua constituição de 100% de oxalato de cálcio. Cinco dias após a cirurgia, a paciente
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apresentou níveis normais de creatinina (1,53 mg/dL). Treze dias após a cirurgia, o
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hemograma não apresentou alteração, assim como creatinina sérica, ureia, fósforo, potássio e
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cálcio ionizado.
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abdominal. Em comparação ao exame anterior, não houve alteração em relação à imagem
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sonográfica do rim direito; já do rim esquerdo, observou-se ausência na dilatação da pelve,
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bem como do ureter proximal. Atualmente a gata se encontra com normofagia, normodipsia,
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com valores de creatinina e de cálcio ionizado dentro dos valores de referência e exame
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ultrassonográfico indicando a permanência apenas dos dois urólitos no parênquima do rim
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direito, que estão sendo acompanhados a cada três meses através de exames de imagem.
Dezoito dias após a cirurgia foi solicitada uma nova ultrassonografia
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DISCUSSÃO
1347
Em humanos, os sinais clínicos associados à ureterolitíase são dramáticos. Contudo, os
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sinais clínicos em gatos geralmente são mínimos e de difícil percepção [8]. Isto se deve,
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provavelmente, à natureza estóica do gato, que faz com que os sinais de dor sejam sutis,
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podendo se manifestar através da perda de peso [4], como foi relatado no caso.
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A hipercalcemia é um fator de risco para a formação de urólitos de oxalato de cálcio.
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A presença destes urólitos vem sendo observada em até 35% dos gatos com hipercalcemia
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[6]. Assim, a presença de urólitos de oxalato de cálcio deve ser investigada em animais
1354
azotêmicos e/ou hipercalcêmicos, como o que foi realizado no presente caso.
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Métodos de diagnóstico por imagem devem ser utilizados em animais que apresentem
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azotemia. Por serem radiopacos, os urólitos de oxalato de cálcio usualmente são vistos em
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radiografia simples do abdome [7]. Porém, devido ao tamanho reduzido do ureter e à
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sobreposição de estruturas adjacentes, algumas vezes os ureterólitos não são visualizados na
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radiografia, resultando em baixa sensibilidade. Já a ultrassonografia consegue detectar
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pequeno aumento no ureter e na pelve renal, que nem sempre é resultante da presença de um
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ureterólito, havendo baixa especificidade [1,5]. Desta forma, devido à complementaridade das
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duas técnicas anteriormente citadas, a radiografia e o ultrassom abdominais devem ser
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utilizados de forma combinada para que haja 90% de sensibilidade no diagnóstico de
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ureterolitíase em gatos [5]. Diante do caráter corrigível desta nefropatia obstrutiva e da
1365
duração da obstrução ser o fator determinante para o retorno da função renal, é muito
1366
importante que o diagnóstico seja realizado antes que haja danos irreversíveis aos rins [8].
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Possibilitando, desta forma, que o valor de creatinina retorne ao valor de normalidade, como o
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que foi observado no animal.
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Embora a doença renal crônica seja frequente em gatos, há diversas outras causas para
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a ocorrência de azotemia. Muitas destas são reversíveis e o pleno retorno da função renal,
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depende, em muitas ocasiões, do diagnóstico rápido e correto da causa que leva ao
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comprometimento dos rins. Desta forma, a complementaridade entre os métodos de
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diagnóstico por imagem deve empregada em pacientes nefropatas, objetivando identificar a
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causa da nefropatia.
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MANUFACTURERS
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1
MSD Saúde Animal. São Paulo, SP, Brazil.
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2
Agener União Saúde Animal. São Paulo, SP, Brazil.
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3
Manipulado em farmácia de manipulação. Porto Alegre, RS, Brazil.
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REFERENCES
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1 Adin C.A., Hergessel E.J., Nylan T.G., Hughes J.M., Gregory C.R., Kyles A.E., Cowgil
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L.D. & Ling G.V. 2003. Antegrade pyelography for suspected ureteral obstruction in cats:
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11 cases (1995-2001). Journal of the American Veterinary Medical Association. 222(1):
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1576-1581.
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2 Adin C.A. & Scasen B.A. 2011. Complications of upper urinary tract surgery in companion
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animals. Veterinary Clinics of North America: Small Animal Practice. 41(5): 869-888.
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3 Bartges J. Feline calcium oxalate uroliths. 2002. Veterinary Information Network. [Fonte:
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<http://www.vin.com/Members/Proceedings/Proceedings.plx?CID=wvc2002&PID=pr00995
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&O=VIN>]. [Acessado em mes/ano].
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4 Cambridge A.J., Tobias K.M., Newberry R.C. & Sarkar D.K. 2000. Subjective and
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objective measurements of postoperative pain cats. Journal of the American Veterinary
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Medical Association. 217(4): 685-690.
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5 Kyles A.E., Hardie E.M., Wooden B.G., Adin C.A., Stone C.A., Gregory C.R.,
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Mathews K.G., Cowgil L.D., Vanden S., Nylan T.G. & Ling G.V. 2005. Clinical,
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clinicopathologic, radiographic and ultrasonographic abnormalities in cats with ureteral
1396
calculi: 163 cases (1984-2002). Journal of the American Veterinary Medical Association,
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226(6): 932-936.
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6 Lulich J. 2006. Feline urolithiasis: managing the consequences of an epidemiological
1399
shift in urolith type. In: Hill’s European Symposium on Advances in Feline Medicine
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(Brussels, U.S.A.). pp.44-52.
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7 Palm C. & Westropp J. 2011. Cats and calcium oxalate: strategies for managing lower and
1402
upper tract stone disease. Journal of Feline Medicine and Surgery. 13(9): 651-660.
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8 Polzin D., Ross S., Osborne C. & Lulich J. 2003. Urolithiasis and feline renal failure part
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II.
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<http://www.vin.com/Members/Proceedings/Proceedings.plx?CID=acvim2003&PID=pr0436
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2&O=VIN>]. [Acessado em mes/ano].
American
College
of
Veterinary
Medicine
Forum.
[Fonte:
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Figura 1. Imagem radiográfica em projeção laterolateral (A) e ventrodorsal (B) do abdome.
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Notar a presença de duas estruturas de densidade mineral em região da pelve renal direita
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(seta pequena), em ambas as projeções, sugestivo de litíase renal. Observar também, outra
1411
estrutura radiopaca ventral ao corpo vertebral da quarta vértebra lombar em A, e lateral a este
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em B (seta grande). A imagem é compatível com litíase em ureter esquerdo.
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