Prevalence of drug resistance in Thai human immunodeficiency virus seropositive tuberculosis patients.

The emergence of drug resistant tuberculosis has been reported from many countries which have had epidemics of human immunodeficiency virus (HIV) infection. This study was conducted at the Central Chest Hospital, Thailand in order to determine the prevalence of drug resistance before treatment in Thai HIV-infected tuberculosis patients. From the Statistics and Registration Unit, pulmonary tuberculosis patients with HIV seropositivity were matched in terms of age and gender with control cases who attended the tuberculosis clinic on the same day. Results of sensitivity test were obtained from record cards in the Microbiology Section. The method for determining the sensitivity test was absolute concentration. During the study period from January 1988 to December 1993, 798 patients were registered as having tuberculosis and HIV infection. Only 406 sensitivity tests were available before treatment and resisted to Isoniazid 56 (13.8%), rifampicin 36 (8.9%), ethambutol 6 (1.5%), streptomycin 64 (15.8%) and Multidrug resistant (MDR)- TB 11 (2.7%). In the control group, 475 tests were available and resisted to isoniazid 61 (12.8%), rifampicin 52 (10.9%), ethambutal 2 (0.4%), streptomycin 46 (9.7%) and MDR-TB 13 (2.7%). The prevalence of resistance to each drug was not significantly different except for streptomycin. We concluded that the prevalence of antituberculous drug resistance among Thai HIV-infected tuberculosis patients was not higher than among general tuberculosis patients.