Clinical Importance Of Nontuberculous Mycobacteria In Chronic Pulmonary Lung Diseases

Introduction: The isolation of non – tuberculous mycobacteria (NTM) from clinical specimens is becoming common in mycobacteriology laboratories. Globally, the NTM’ s are perceived as a contaminant only. Concomitantly NTMs are observed to be another major causative agent of pulmonary and extrapulmonary diseases in immunocompetent patients. It calls for a different line of diagnosis. To complement the paradox on role of NTM, its isolation, identification and diagnosis, a study was carried out in symptomatic patients attending OPD of NITRD New Delhi. Materials & Methods: The study was conducted on the patients whose first sputum culture report was positive for NTM in the microbiology laboratory. At the time of enrollment, second sputum sample was collected along with patient’s clinical data and radiological finding. The results of 2 sputum culture along with clinical & radiological features were recorded and co–related. During the study, tracing of the patients was done mainly through 3 different methods (i) Patients were traced during the report collection in microbiology laboratory by clinical microbiologist, (ii) Through laboratory records registration number address and/or phone number iii)By the help of field worker of the DOTS Centre. Cultures were done in MGIT 960 automated bacterial culture system and identification was done through routine biochemical character. Conclusion : It is imperative on the part of microbiologist to carry out identification tests on all culture isolates before DST is done as 50 % of the laboratory isolates were positive for NTM in repeat samples. Any of the standard tests for M. Tb complexes turn out to be negative;microbiologist shall look for NTM’s. For this purpose a checklist to be developed to avoid delay in diagnosis of NTM related diseases.