Non-tuberculous mycobacteria isolated in microbiological samples, at the General Hospital of Granollers

Isolation of non-tuberculous mycobacteria (NTM) in microbiological samples often has an uncertain clinical significance. Epidemiological data show a worldwide increase of NTM infections for multifactorial reasons (pathogen, host and the interaction of both with the environment) <b>Aim:</b> To describe the isolated NTM strains in microbiological samples and its clinical presentation for the last 11 years in our hospital; and to compare the results with a previous series of ours <b>Method:</b> We reviewed all the NTM strains isolated from 2008 to 2018 (current period or CP), and the clinical data of the patients. Results were compared with a previous series from 1997 to 2007 (previous period or PP). NTM considered to be environmental pollutants were excluded <b>Results:</b> Eighty-four strains were isolated in the CP and 34 in the PP. Seventy-eight strains in the CP and 22 in the PP were isolated in respiratory samples. The frequency of NTM species in respiratory samples in the CP were: M. avium complex (MAC): 44% (M. avium: 22%, M. intracellulare: 19% and M. avium-intracellulare: 3%), M. xenopi: 26%, M. chelonae: 8%, M. kansasii: 6%; and in the PP: MAC: 41%, M. kansasii: 36%. In the CP, the NTM strains were isolated from 70 patients (57 men; mean age 64 y; 72% suffered chronic respiratory disease and/or were immunocompromised). 74% of the patient had a pathological X-ray (cavitation, nodules or pneumonia) <b>Conclusions:</b> Comparing the 2 periods, we observe in our environment: 1. An increase in total isolation of NTM strains, with a significant increase from respiratory samples; 2. A significant decrease of NTM strains isolated in non-respiratory samples; 3. The MAC is still the most frequently NTM isolated