To determine the acquired resistance of mycobacterium tuberculosis by culture to 1st line anti-tuberculous drugs in non responding smear positive patients who have taken category 1

Abstract

Background: The strongest risk factor for drug resistance is previous history of tuberculous treatment. Currently the national tuberculosis control program recommends drug susceptibility testing in failures of retreatment cases. This study is being conducted to see the drug resistance pattern in failures and defaulters of initial treatment before starting a retreatment regime

Material and methods: Study Design: Descriptive case series

Setting: This study was conducted in the OPD of Thoracic Medicine JPMC Karachi.

Sampling technique: Non probability purposive sampling.

Results: Among 60 selected patients of category 1 sputum smear positive, 14 (23.3%) were defaulter, 38 (63.3%) relapse and 8 (13.3%) patients were of treatment failure.

Culture sensitivity has shown 58 (96.7%) positive patients and only two (3.3%) were negative.

Multidrug resistance was found in 15 (25%) patients. MDR cases were 6 (42.9%) among 14 defaulters, 4 (10.5%) among 36 relapsed and 5 (62.5%) among 8 treatment failure patients.

Rifampicin resistance was found in 20 (34.5%) patients. Isoniazid was resistant in 19 (32.8%) patients. Ethambutol was resistant in 21 (36.2%) patients. Pyrazinamide was resistant in 17 (29.3%) patients. Streptomycin was resistant in 10 (17.2%) patients. None of antitubercolous drug was resistant among two culture negative patients. Multidrug resistance (MDR) was observed in 15 (25.9%) patients.

Conclusion: We conclude that levels of MDR-TB is very high in patients not responding to CAT1 anti tuberculous drugs in our community.