COMEDK 2007 MCQ Answer 175

The correct answer is A

The Indian Council of Medical Research (ICMR) undertook drug resistance studies during 1965-67 in nine urban areas of the country. The first study was on patients who had denied any history of previous treatment, while in the second study, patients with and without previous chemotherapy were included. The results showed that in the first study resistance to isoniazid ranged from 11-20 per cent, to streptomycin from 8-20 percent and to both drugs from 4-11 per cent. The second study showed resistance to isoniazid to range from 15-69 percent, to streptomycin from 12-63 per cent and to both drugs from 5-58 per cent.A decade later, a study at the Government Chest Institute and Chest Clinic of Government Stanley Hospital (GCI-SH), Chennaai20 yielded results similar to those in earlier ICMR surveys, indicating that the prevalence of initial drug resistance had not risen during the span often years.

However, both the above studies were undertaken in the pre-rifampicin era and are not of relevance in the present setting.

In the early 1990s, a retrospective study done at New Delhi showed a high level of initial drug resistance to isoniazid (18.5%) and a low level of resistance to rifampicin.

At present resistance to Isoniazid is highest when compared to other anti- tubercular drugs.

Source: Drug resistance in tuberculosis in India,Indian Journal of Medical Research, Oct 2004 by Paramasivan, C N, Venkataraman, P