Mycobacterium malmoense in the north-east of England.

We report a 6 year experience (1979-1984) of isolating Mycobacterium malmoense in the north-east of England. Eleven subjects were involved of whom 10 had active infection--9 pulmonary, one cervical adenitis. The 11 new isolates represent 0.7% of all new mycobacterial isolates during this period and 10% of new non-tuberculous isolates. In all but 2 cases there was pre-existing pulmonary disease and/or a recognised predisposing factor to mycobacterial infection. The organisms were generally insensitive to isoniazid but sensitive to both rifampicin and ethionamide. The results of chemotherapy are described.