Elevated neutrophil function in chronic neutrophilic leukemia.

A 65-year-old man with marked leukocytosis was admitted for diagnosis and treatment. His peripheral blood leukocyte count was 37,500/microliters and the leukocytes consisted of mature neutrophil-like cells. A high neutrophil alkaline phosphatase score and a normal bone marrow cell karyotype suggested that the patient had chronic neutrophilic leukemia rather than chronic myeloid leukemia. Several neutrophil functions, such as superoxide production, nitroblue tetrazolium reduction activity, and phagocytosis, were elevated. These data and the morphological features (toxic granules and Döhle bodies) indicated that the patient's neutrophils were in an activated stage.