Nontuberculous mycobacteria in non-AIDS patients

Nontuberculous mycobacteria (NTM) play an increasingly significant pathogenic role in HIV -positive patients, in patients with chronic lung disease, in other chronic conditions and in the elderly.

Evaluate the importance of NTM isolation in respiratory samples in patients without HIV-infection.

Retrospective evaluation of our hospital patients with no known AIDS, with at least one NTM positive respiratory sample, from 1997 -2004.

We found 102 patients, with a median age of 63 years; 67% male. Sixty -three (62%) had underlying lung disease, mainly tuberculosis sequelae (n=19). The majority (47%) of the isolations were Mycobacterium avium complex (MAC). A diagnosis of Mycobacterium pulmonary disease was made in 16 patients (15.7%), 14 of which met the American Thoracic Society diagnostic criteria. Ten male and 6 female; median age 65 years. Twelve had underlying lung disease. All of them had respiratory infection complaints. Chest X -rays showed mainly pulmonary infiltrates, linear opacities and cavitation. MAC was the cause of mycobacterium respiratory disease in 12 patients (75%).

NTM isolation did not equal pulmonary NTM disease in the majority of cases, even in patients with underlying lung disease. MAC was the most commonly isolated agent and its relative importance was higher in the presence of NTM disease.