[Pulmonary disease caused by opportunistic environmental mycobacteria. Review of 35 cases]

The clinical characteristics, radiologic findings, and therapeutic response in 35 cases of pulmonary disease induced by opportunistic environmental mycobacteria collected during a period of 4 years are reported. These cases included 21 infections by Mycobacterium kansasii, 10 by M. xenopi, and 4 by M. avium. The cases reported constituted the 6% of all mycobacterial infections of the lung observed in our institution. The mean age of the patients was 56 years and 83% of them were male. The presence of previous pulmonary involvement was rather frequent, specially the existence of chronic limitation of the air flow (CLAF) (91%) and previous tuberculosis (29%). The clinical symptoms were almost nonspecific and they could frequently be misinterpreted as an intercurrent infection in cases of CLAF. The radiologic findings could not be distinguished from an infection by M. tuberculosis. The clinical course with pharmacologic first line therapy (93% of cases) was satisfactory in 28 patients in whom follow-up controls are available.