Selective myeloid aplasia: a long-lasting presentation of an unusual hairy cell leukemia variant?

A rare aleukemic myeloaplastic presentation of hairy cell leukemia (HCL) is described. The patient was observed for 11 years and presented a clinical picture suggestive of pure white cell aplasia for seven years. Hairy cells (HC) were first discovered in the bone marrow, then occasionally in the blood during the last four years. A brief course of low-dose alpha interferon promptly induced prolonged remission of neutropenia. In our opinion, this case, as few others described till now, should be considered a rare HCL variant, an understanding of which offers an important clinical opportunity for investigating the myeloid inhibitory activity of hairy cells.