Focal nodular hyperplasia of the liver in a free-ranging opossum (Didelphis marsupialis)
Souza, Alex Junior Souza deSilva, Carlos Augusto MoreiraSoares, Manoel do Carmo PereiraCogliati, BrunoSá, Lilian Rose Marques de
Background: Focal Nodular Hyperplasia (FNH) in the liver is a solid lesion characterized by spontaneous benign nonneoplastic hepatocellular proliferation that occurs in animals and humans. The clinical course of FNH is usually asymptomatic in animals and humans; and its diagnosis is often an incidental finding during surgery, necropsy/autopsy, or imaging procedures for unrelated symptoms. Despite the lack of clinical significance or malignant transformation potential, FNH is an important differential diagnosis of hepatocellular adenoma, well-differentiated hepatocellular carcinoma, nodular regenerative hyperplasia and metastatic disease. FNH is particularly uncommon in wild marsupials and other wild animals and this study aimed to describe for the first time the occurrence of hepatic FNH in a free-ranging marsupial.Case: During the fieldwork activities for investigation of liver diseases in wild animals, a well-demarcated, non-encapsulated focal nodule measuring 2.0 x 1.5 x 2.0 cm was observed on the parietal surface of right liver lobe of a wildlife adult female opossum (Didelphis marsupialis) from Anajás City, Marajó Island, Brazil. The nodule had a smooth, tan-to-yellow cut surface with small reddish areas devoid of visible fibrous bands and/or scars. The opossum was in good body condition and no other gross lesions were observed. Liver samples were collected, fixed in 10% buffered formalin and routinely processed for histopathological analysis. Tissue samples were embedded in paraffin, cut in 5 µm sections, stained with hematoxylin and eosin (HE), Massons trichrome (MT), reticulin and Perls stains and the slides were evaluated under light microscope. Liver tissue samples were also snap frozen in liquid nitrogen and submitted to DNA and RNA extraction for molecular screening for Orthohepadnavirus and Hepacivirus (homologous to hepatitis B and C viruses respectively) by previously described nested PCR and RT-PCR techniques.[...](AU)
Texto completo