Human immunodeficiency virus-related tuberculosis and primary drug resistance in Bangkok, Thailand.

Central Chest Hospital, a 500-bed referral hospital near Bangkok with a large out-patient department. To determine human immunodeficiency virus (HIV) seroprevalence among patients with pulmonary tuberculosis (TB), and compare HIV-positive and HIV-negative TB patients. From July 1995 through June 1996, a cross-sectional study was conducted of newly registered adults (> or =16 years old) with suspected pulmonary TB. Of 2587 newly registered patients with suspected pulmonary TB, 2019 (78%) received HIV pretest counseling and 1816 (90%) consented to testing. Of these, 364 (20%) were HIV-seropositive. Among 1091 patients with bacteriologically confirmed TB, HIV seroprevalence was 22%. HIV-positive patients were more likely to be young, unemployed, single men and to have a history of injection drug use. HIV-positive patients with first-episode TB were more likely to have Mycobacterium tuberculosis strains resistant to isoniazid (10.9% vs 3.5%; P < 0.001), rifampicin (9.4% vs 2.9%; P < 0.001), and at least isoniazid and rifampicin (multidrug-resistant TB [MDR-TB]; 5.2% vs 0.4%; P < 0.001). HIV prevalence is high among TB patients at this Bangkok hospital and is associated with drug resistance, including a 12 times higher risk of MDR-TB. These findings underscore the urgent need to assure adherence to complete, effective TB treatment regimens for all patients, including persons who are potentially difficult to manage such as injection drug users.