Hairy cell leukemia and vasculitis.

A patient with hairy cell leukemia, systemic vasculitis, and HB8 antigenemia is reported. The patient presented with polyarthralgia before the diagnosis of the leukemia and had documented polyarthritis before the subsequent recognition of the vasculitis. The association of systemic vasculitis and hairy cell leukemia in the setting of HB8 antigenemia is discussed. The therapeutic challenge of treating coincident hairy cell leukemia and vasculitis is presented.