First- and second-line drug resistance patterns among previously treated tuberculosis patients in India.

Culture and drug susceptibility testing results of 2816 tuberculosis (TB) patients from across India who had failed repeated treatments from 2001 to 2004 were retrospectively analysed at the Tuberculosis Research Centre, Chennai. Of 1498 (53%) identified as having multidrug-resistant TB (MDR-TB), 671 (44.8%) were resistant to > or =1 second-line drugs (SLDs): 490 (32.7%) to ethionamide, 245 (16.4%) to ofloxacin and 169 (11.3%) to kanamycin; 69 (4.6%) were extensively drug-resistant TB (XDR-TB). Although from a highly select and non-representative patient group, such high SLD resistance levels, including XDR-TB, among MDR-TB patients is of concern. The prevention of MDR/XDR-TB through quality DOTS services, however, remains the priority. In addition, rapid scale-up of quality programmatic management under the RNTCP is needed, with more control and rational use of SLDs outside the programme.