Chronic lymphopenia and neutropenia in a dog with large granular lymphocytic leukemia.

T-cell large granular lymphocytic leukemia (T-cell LGLL) is the most common presentation of chronic lymphocytic leukemia (CLL) in dogs. Aleukemic or subleukemic leukemia is a particularly rare variation in both humans and dogs, where bone marrow proliferation is either not or only sparsely translated in the peripheral blood. Neutropenia is a prominent feature in cases of human T-cell LGLL but is normally absent in canine CLL. This report describes a case of a dog presented with an almost 3-year history of asymptomatic neutropenia, lymphopenia, and thrombocytopenia (without anemia). A bone marrow examination, the exclusion of infectious diseases, and clonality testing led to the diagnosis of subleukemic LGLL that responded well to therapy (death occurred 2.5 years later due to an unrelated cause).