Diagnosis of feline infectious peritonitis by immunohistochemistry and histopathology methods: a case report based on diagnostic approach

Aim: In this study the case of feline infectious peritonitis (FIP) has been identified as histopathological and immunohistochemical (IHC) in a 6-month-old male domestic shorthair cat. In necropsy, the abdominal cavity contained a significant volume of yellow liquid and granular fibrinous exudate was seen on the liver, serosa of intestines, and peritoneum. Microscopically, inflammatory cell infiltration and fibrin exudation, consisting mainly of macrophage, lymphocyte and plasma cells, were determined around small and medium-sized vessels in the tunica serosa layer of the intestines. Many granulomatous foci of various sizes, with or without necrosis, were found in the liver, spread to the parenchyma. In methyl green pyronin staining, plasma cells were found to be the majority of the inflammatory cells present in lesions. In IHC staining with specific antibodies against the agent, immunopositivity was obtained in granulomatous lesions in the serosa layer of the intestines and less frequently in the cytoplasm of mononuclear cells in the lamina propria. Immunoreactivity was detected in the cytoplasm of macrophages in the liver, around both pyrogranulomas and granulomas. It was concluded that this case of FIP, when all findings are evaluated together, may have started as a dry form, and turned into a wet form in the terminal period

Mycobacterium bovis tuberculosis in a neonatal holstein calf

In this study, a case of exudative type tuberculosis due to M. bovis infection was identified in a 2 month-old Holstein female calf that was treated with antibiotic treatment due to cough and respiratory problems in the neonatal period. Systemic necropsy revealed caseific nodules scattered across the entire lung, except the dorsal parts of the caudal lobes of the lung, and prominent interlobular edema was observed in the dorsal caudal regions. Histopathologically, exudative lesions that extensive caseification necrosis and calcification with diffuse inflammatory cells and Langhans type giant cells without fibrous capsule were seen in the lung parenchyma. Smaller and lesser number of similar granulomas was found in the liver and brain. Acid resistant bacteria in Ziehl-Neelsen staining were determined to be Mycobacterium bovis in immunohistochemical staining. It is aimed to draw attention to the fact that bovine tuberculosis should be considered as one of the important diseases affecting the calves in the neonatal period and may cause serious economic losses if no measures are taken