Identification of the Hairy Cells of Leukaemic Reticuloendotheliosis by an Esterase Method

Abstract
A distinctive pattern of .alpha.-naphthyl butyrate esterase positivity was observed in all of a series of 14 patients with HCL. This pattern was not observed in a range of other hematological malignancies including 9 cases of CLL [chronic lymphocytic leukemia], 2 cases of Sezary''s syndrome, 6 cases of null cell ALL [acute lymphocytic leukemia], 2 cases of Schilling-type monocytic leukemia and 1 case of lymphosarcoma cell leukemia. The potential diagnostic value of this simple cytochemical test is discussed in relation to existing methods.