Chronic granulocytic leukaemia in a dog with associated bacterial endocarditis, thrombocytopenia and preretinal and retinal haemorrhages

The clinical, haematological and pathological features of a case of chronic granulocytic leukaemia (CGL) associated with valvular bacterial endocarditis are described in a nine-year-old male Springer Spaniel. The disease was characterized clinically by lethargy, weight loss, hepatosplenomegaly, anaemia and leucocytosis. Severe thrombocytopenia resulted in preretinal and retinal haemorrhages. A diagnosis of CGL was based on the finding of a hypercellular bone marrow with increased M: E ratio and morphologically abnormal myeloid precursors. The dog terminally became leucopenic and bacteraemic. Necropsy revealed invasion of liver, spleen and bone marrow with a pleiomorphic population of myeloid blast cells, consistent with transition to a blast cell crisis.