Objectives: To study the positivity of sputum acid fast bacilli (AFB) smears in patients with pulmonary tuberculosis using 24 hour sputum collection. To detect HIV seropositivity in patients suffering from tuberculosis, and to analyse the pattern of tuberculosis disease in this subgroup. To determine the outcome of patients treated with directly observed therapy. Setting: The tuberculosis referral unit of a tertiary care hospital. Design: A total of 893 consecutive patients with tuberculosis, diagnosed between 1 November 2000 and 30 September 2002, were included in the study. An HIV test was performed in all patients, with adequate counselling and informed consent. Treatment was prescribed as per World Health Organisation treatment categories. Results: Out of 893 patients with tuberculosis, 695 had pulmonary tuberculosis and 198 had extrapulmonary tuberculosis. Out of the 695 pulmonary tuberculosis patients, 673 (96.8%) were sputum smear AFB positive. Overall, 71 patients (8.0%) were HIV positive. The pattern of tuberculosis was the same in HIV seropositive and seronegative patients. Treatment outcome could be analysed in 112 out of 150 patients: 78 patients (70%) were declared cured or completed treatment. Conclusions: Sputum smear AFB could be a very sensitive test when a large quantity of sputum is used. The presence of HIV coinfection does not alter the clinical presentation. Only 70% of patients treated were cured/completed treatment, in spite of a strict directly observed therapy