Resistance to anti-tuberculosis drugs among smear-positive cases in Thai prisons 2 years after the implementation of the DOTS strategy.

Setting: Three prisons in Bangkok and vicinity, Thailand.
Objective: To examine the prevalence of drug-resistant tuberculosis among smear-positive cases in Thai prisons 2 years after the implementation of the DOTS strategy, and to identify factors associated with resistance to anti-tuberculosis drugs.
Methods: In a cross-sectional study, 154 consecutive tuberculosis patients with at least one positive sputum smear and at least one positive sputum culture registered between 1 May and 31 October 2000 were enrolled. Drug susceptibility testing was performed by the Ministry of Public Health Tuberculosis Division. Patient characteristics were obtained by face-to-face interview.
Results: Resistance to at least one drug was found in 50.6% of the subjects, including multidrug-resistant tuberculosis (MDR-TB) in 19.5%. The proportion of resistance to any anti-tuberculosis drug in prisons A, B and C was respectively 52.7%, 37.8% and 61.5%. The only factor significantly associated with resistance to at least one drug (P = 0.011) and MDR-TB (P < 0.001) was a history of previous tuberculosis treatment.
Conclusion: After 2 years of the DOTS strategy, resistance to anti-tuberculosis drugs, an indicator of the quality of tuberculosis treatment, was found to be high. The DOTS strategy currently used in Thai prisons should be reviewed, in order to reduce and prevent drug-resistant tuberculosis.