OBJECTIVE: To determine the proportion and profile of antituberculosis drug resistance among Mycobacterium tuberculosis isolates in Thailand. SETTING: A 500-bed cardiothoracic centre. DESIGN: From January to December 1996, isolates of M. tuberculosis from consecutive patients with pulmonary tuberculosis underwent susceptibility testing to isoniazid (H), rifampicin (R), ethambutol (E), streptomycin (S), kanamycin (K), and ofloxacin (O). RESULTS: In all, 1861 strains were tested, 1738 from new cases and 123 from previously treated cases. Overall initial and acquired resistance were 20.9% and 53.6%, respectively. The percentages of initial resistance to R, H, S, O, K and E were 12.6, 8.3, 6.6, 1.8, 1.1 and 0.8, respectively, whereas those of acquired resistance were 43.0, 29.2, 21.1, 9.7, 8.1 and 4.8, respectively. Multidrug resistance was observed in 4.2% of new patients and 25.2% of previously treated patients. CONCLUSION: The overall drug resistance of M. tuberculosis in the central region of Thailand is high, and acquired multidrug resistance has reached an ominous level. The results have serious implications for tuberculosis control in Thailand. Urgent measures are needed to control the spread of drug resistance, and supervised treatment of standard protocol should be adhered to more strictly.
OBJECTIVE: To determine the proportion and profile of antituberculosis drug resistance among Mycobacterium tuberculosis isolates in Thailand. SETTING: A 500-bed cardiothoracic centre. DESIGN: From January to December 1996, isolates of M. tuberculosis from consecutive patients with pulmonary tuberculosis underwent susceptibility testing to isoniazid (H), rifampicin (R), ethambutol (E), streptomycin (S), kanamycin (K), and ofloxacin (O). RESULTS: In all, 1861 strains were tested, 1738 from new cases and 123 from previously treated cases. Overall initial and acquired resistance were 20.9% and 53.6%, respectively. The percentages of initial resistance to R, H, S, O, K and E were 12.6, 8.3, 6.6, 1.8, 1.1 and 0.8, respectively, whereas those of acquired resistance were 43.0, 29.2, 21.1, 9.7, 8.1 and 4.8, respectively. Multidrug resistance was observed in 4.2% of new patients and 25.2% of previously treated patients. CONCLUSION: The overall drug resistance of M. tuberculosis in the central region of Thailand is high, and acquired multidrug resistance has reached an ominous level. The results have serious implications for tuberculosis control in Thailand. Urgent measures are needed to control the spread of drug resistance, and supervised treatment of standard protocol should be adhered to more strictly.