Tuberculosis has been reported previously in patients with acquired immunodeficiency syndrome who are at increased risk of prior infection with Mycobacterium tuberculosis. We performed a population-based study of AIDS and tuberculosis in San Francisco using the Tuberculosis and AIDS Registries of the San Francisco Department of Public Health. Of 287 cases of tuberculosis in non-Asian-born males 15 to 60 yr of age reported from 1981 through 1985, 35 (12%) also had AIDS, including 23 American-born whites. Patients with tuberculosis and AIDS were more likely to be nonwhite and heterosexual intravenous drug users than were AIDS patients without tuberculosis. Fifty-one percent had tuberculosis diagnosed before AIDS, and 37 percent had AIDS diagnosed at least 1 month prior to the diagnosis of tuberculosis. Although the lungs were the most frequent site of tuberculosis in both AIDS and non-AIDS patients, 60% of the AIDS group had at least 1 extrapulmonary site of disease compared to 28% of the non-AIDS group (p less than 0.001). Nonsignificant tuberculin skin tests were more common in AIDS patients (14 of 23 patients tested) than in non-AIDS patients (12 of 129 patients tested; p less than 0.0001). Chest radiographs in AIDS patients showed predominantly diffuse or miliary infiltrates (60%), whereas non-AIDS patients had predominantly focal infiltrates and/or cavitation (68%). Response to antituberculosis therapy was favorable in AIDS patients, although adverse drug reactions occurred more frequently than in non-AIDS patients (p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)