Anti-tuberculosis drug resistance in patients with HIV and tuberculosis in South India.

SETTING: Tuberculosis Research Centre clinics at Chennai and Madurai, Tamil Nadu, South India. OBJECTIVES: To investigate the prevalence and pattern of drug resistance among patients with HIV and pulmonary tuberculosis (PTB). DESIGN: Prospective cohort study of HIV-positive patients with PTB between January 2001 and May 2003. Sputum mycobacterial culture and drug susceptibility testing were performed. RESULTS: A total of 204 patients with positive sputum cultures for Mycobacterium tuberculosis were included; 167 of them were new cases, and 37 had a history of previous anti-tuberculosis treatment for > 1 month. Among the former, resistance to isoniazid (INH) was observed in 22 (13%) and MDR-TB in 7 (4.2%). Reported resistance rates in this geographic area among new cases ranged from 15% to 28% for INH and 2.8% to 3.4% for MDR (INH + rifampicin [RMP]). In contrast, among HIV-positive patients with a history of previous treatment, resistance was found to INH in 10 (27%) and to RMP in 7 (18.9%), while MDR-TB was seen in 5 (13.5%) patients. CONCLUSION: Among new TB patients, MDR-TB is marginally higher in HIV-positive patients than in the non-HIV-infected population in this region. Standard treatment guidelines should be followed. Higher rates of drug resistance are observed among previously treated patients.