Pulmonary disease caused by non-tuberculous mycobacteria. Descriptive study and comparison with mycobacterium tuberculosis

Aim: To describe the epidemiological, clinical and radiological data of pulmonary disease (PD) caused by non-tuberculous mycobacteria (NTM) diagnosed in a period of 12 years in an area of Vizcaya, and to compare the incidence with the cases of M. tuberculosis (MT). Material: We reviewed all cases of PD caused by mycobacteria between 1997-2008 in our center, attending a population of 420,000. The diagnosis of NTM PD was conducted according to criteria of ATS. Results: We found 1019 cases of PD caused by mycobacterias,788 (77.3%) for MT and 231 (22.7%) NTM: 216 M. kansasii (MK), 11 M. avium complex (MAC), 2 M. abscessus, 1 M.xenopi and 1 M. celatum. NTM PD was more frequent in men (73.2%) and the mean age was 53.9. 2.8% of patients with MK and 9.1% of patients with MAC had extrapulmonary affection. 36 patients (15.6%) had HIV coinfection.Cavitary pulmonary infiltrates were the most common (56.1%), followed by reticulonodular infiltrates (31.9%). The location was unilateral in 54% and affection in upper lobes was observed in 82.6%.The mean age of patients infected by MT was 48.7 and was more frequent in men (60%). 53 patients (6.7%) had HIV coinfection. The annual incidence rate/100.000 of MT infection had the highest peak in 1999 with 22.8 and the lowest in 2008 with 11.9.The highest rate of NTM infection was in 1998 (7.4) and lowest in 2008 (1.2). Conclusions: 1)The most common NTM specie in our area is M.Kansasii. The rest of NTM causes PD infrequently. 2) PD by NTM has a clinical and radiological presentation similar to tuberculosis. 3) The incidence of PD by NTM and MT had a descendant tendency in the 12 years studied, which is more remarkable since 2005.