October 2017



Signalment (JPC #2237801):  Adult female king snake

HISTORY:  This is one of six snakes in a private collection of over 250 snakes that developed vomiting and runny yellow feces over a period of 6 months.  Three snakes died.

HISTOPATHOLOGIC DESCRIPTION:  Lung:  Diffusely faveolar septa are markedly expanded up to 100 microns by edema, fibrin, congestion, and low numbers of macrophages, lymphocytes and heterophils.  Multifocally pneumocytes lining faveolar lumina are lined by plump cuboidal epithelial cells that are hyperplastic (type II pneumocyte hyperplasia).  Rare pneumocytes are necrotic characterized by hypereosinophilic cytoplasm and pyknosis or karyorrhexis, or pneumocytes form 30 um diameter syncytial cells with up to 10 nuclei.  Pneumocytes and syncytial cells contain variably sized and shaped 3-5 micron eosinophilic intracytoplasmic viral inclusion bodies.   Multifocally, faveolar lumina are variably occluded by many degenerate heterophils, occasional macrophages, and sloughed epithelial cells admixed with abundant cellular and karyorrhectic debris (necrosis). The respiratory epithelium lining the septal apices and central lumen is diffusely hyperplastic, piling up to 7 cell layers thick. Epithelial cells are often swollen and vacuolated (degenerate) and contain similar intracytoplasmic inclusions. The pleura is diffusely expanded up to 1 mm by edema, congested vessels, low numbers of lymphocytes, plasma cells, macrophages, and heterophils. 

MORPHOLOGIC DIAGNOSIS:  Lung:  Pneumonia, interstitial, proliferative and lymphohistiocytic, diffuse, moderate, with type II pneumocyte hyperplasia, syncytial cells, and intracytoplasmic eosinophilic inclusion bodies, etiology consistent with Ferlavirus, King Snake (Lampropeltis spp.), reptile.

ETIOLOGY:  Ferlavirus

ETIOLOGIC DIAGNOSIS:  Ferlaviral pneumonia

SYNONYMS:  Ophidian (snake) paramyxovirus (OPMV), Viper pneumonitis virus, Fer-de-lance virus











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