Drug susceptibility pattern of Mycobacterium tuberculosis isolates against conventional anti-tuberculosis drugs in Dhaka, Bangladesh.

OBJECTIVES: To investigate the drug susceptibility pattern of isolated Mycobacterium tuberculosis (M. tuberculosis) against conventional anti-tuberculosis drugs in Dhaka, Bangladesh.

METHODS: Sputum samples from 101 suspected new and previously treated patients were collected and M. tuberculosis was identified by microscopic observation and Ziehl-Neelsen staining. Drug susceptibility was performed against 4 anti-tuberculosis drugs, and the obtained data was analyzed. This study was performed in the Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders Hospital, Dhaka, Bangladesh between October 2008 and November 2009.

RESULTS: Among 101 suspected, 59 (58.4%) cases were identified as M. tuberculosis and the drug susceptibility pattern of 50 positives isolates was studied against 4 anti-tuberculosis drugs. Out of these 50 isolates of M. tuberculosis, 25 (50%) were sensitive to all drugs, and 25 (50%) were resistant to one or more drugs. Among 50 positive patients, 37 (74%) were new cases, and 13 (26%) were previously treated cases. Among 37 new cases, 14 (37.8%) cases were resistant to one or more drugs, whereas 11 out of 13( 84.6%) treated cases were resistant to one or more drugs. Among the 50 positive isolates, 26% demonstrated resistance to isoniazid, 12% to rifampicin, 22% to streptomycin, 20% to ethambutol, and 8% to multi drug resistance.

CONCLUSIONS: The emergence of drug resistant M. tuberculosis isolates in Dhaka is alarming, which is currently 5-fold higher than last decade. Strict measures should be taken to control and prevent drug-resistant tuberculosis.