Loeffler's Endocarditis and Bicavity Eosinophilic Effusions in a Dog with Visceral Mast Cell Tumour and Hypereosinophilia

SummaryA 9-year-old crossbred dog was presented with a 2-week history of diarrhoea and tachypnoea. Marked circulating eosinophilia was identified. Pleural and abdominal effusions were detected by radiography and ultrasonography and cytological examination of these fluids revealed a predominance of eosinophils. Splenic and hepatic cytology revealed mast cell neoplasia, which was confirmed as visceral mast cell tumour on post-mortem examination. Histological changes of myocardial inflammation, necrosis and fibrosis were found. These findings are consistent with Loeffler's endocarditis.