Remember mycobacterial disease in hairy cell leukaemia (HCL).

1Department of Infection and Tropical Medicine, University of Newcastle Medical School, Newcastle General Hospital, Newcastle upon Tyne NE4 6BE, U.K.; 2Department of Haematology, Wansbeck General Hospital, Ashington, Northumberland, U.K.; 3Department of Haematology, Royal Victoria Infirmary, Newcastle upon Tyne, U.K.; 4Regional Centre for Mycobacteriology, Public Health Laboratory Service, Newcastle General Hospital, Newcastle upon Tyne NE4 6BE, U.K.