August 2018

SIGNALMENT (AFIP#1946537):  Tissue from a 4-year-old yellow-naped Amazon parrot

HISTORY: The bird became progressively docile, passive, and depressed.

MICROSCOPIC DESCRIPTION:  Liver:  Multifocally there are random irregularly round, variably sized (up to 1 mm diameter) areas of lytic necrosis characterized by complete loss of hepatic architecture with replacement by eosinophilic cellular and karyorrhectic debris, and heterophils, surrounded by hemorrhage, multinucleated giant cells (foreign body and Langhan’s type), epithelioid macrophages, and fewer lymphocytes and plasma cells.  Multifocally, there are random foci of coagulative necrosis characterized by retention of hepatic cord and cellular architecture with increased cytoplasmic eosinophilia. Multifocally, few random hepatocytes and Kupffer cells contain intracytoplasmic gray indistinct granular coccoid bacteria.  Hepatocytes surrounding areas of necrosis often have vacuolated cytoplasm and are dissociated from hepatic chords (degeneration).  Diffusely, sinusoids are expanded by macrophages, heterophils and lymphocytes.  Multifocally hepatocytes are mildly vacuolated and contain small aggregates of brown, granular pigment (bile, hemosiderin and/or lipofuscin).  Bile ducts are prominent, mildly ectatic, and lined by hyperplastic epithelium characterized by piling up, mild anisokaryosis and increased mitotic activity (regeneration) with adjacent dilated lymphatic vessels and periductular clear space (edema).

MORPHOLOGIC DIAGNOSIS: Liver: Hepatitis, necrotizing, heterophilic and granulomatous, multifocal to coalescing, moderate, with mild bile duct hyperplasia and intracellular bacteria, yellow-naped Amazon parrot (Ochrocephala auropalliate), avian.

ETIOLOGY:  Chlamydophila psittaci

ETIOLOGIC DIAGNOSIS:  Chlamydial hepatitis

CONDITION:  Avian chlamydiosis (birds); psittacosis (humans)











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