Infectious canine hepatitis in naturally infected dogs: Pathological findings and immunohistochemical diagnosis

Oliveira E. C., Almeida P. R., Sonne L., Pavarini S. P., Watanabe T.T.N. & Driemeier D. 2011. [Infectious canine hepatitis in naturally infected dogs: Pathological findings and immunohistochemical diagnosis.] Hepatite infecciosa canina em caes naturalmente infectados: achados patologicos e diagnostico imuno-histoquimico. Pesquisa Veterinaria Brasileira 31(2): 158-164. Setor de Patologia Veterinaria, Faculdade de Veterinaria, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Twenty-three dogs with infectious canine hepatitis (ICH) were analyzed, based on general data, clinicopathological findings, and immunohistochemistry. The main gross lesions were hepatic paleness (17/23), hepatomegaly (10/23), and hemorrhage (21/23). Gallbladder edema (11/23), fibrinous material on the hepatic capsular surface (8/23), and jaundice (6/23) were also found. Severe hepatic necrosis was observed in association with amphophilic or basophilic intranuclear inclusions inside hepatocytes and endothelial cells (22/23). Splenic and nodal lymphoid necrosis and hemorrhage associated with small number of intranuclear inclusions inside reticuloendothelial cells were identified. Immunohistochemistry (IHC) was positive for adenovirus type 1 in all animals, with the best staining pattern occurring in the liver (23/23), brain (22/22), cerebellum (16/20), and kidney (16/21). Greater amount of viral antigen was identified in hepatocytes and vascular endothelial cells from the brain and glomerular tuft.