Objective: We describe chest radiograph (CXR) findings in a population with a high prevalence of human immunodeficiency virus (HIV) and tuberculosis (TB) in order to identify radiological features associated with TB; to compare CXR features between HIV-seronegative and HIV-seropositive patients with TB; and to correlate CXR findings with CD4 T-cell count. Methods: Consecutive adult patients admitted to a national referral hospital with a cough of duration of 2 weeks or longer underwent diagnostic evaluation for TB and other pneumonias, including sputum examination and mycobacterial culture, bronchoscopy and CXR. Two radiologists blindly reviewed CXRs using a standardised interpretation form. Results: Smear or culture-positive TB was diagnosed in 214 of 403 (53%) patients. Median CD4+ T-cell count was 50 cells mm -3 [interquartile range (IQR) 14-150]. TB patients were less likely than non-TB patients to have a normal CXR (12% vs 20%, p50.04), and more likely than non-TB patients to have a diffuse pattern of opacities (75% vs 60%, p50.003), reticulonodular opacities (45% vs 12%, p,0.001), nodules (14% vs 6%, p50.008) or cavities (18% vs 7%, p50.001). HIV-seronegative TB patients more often had consolidation (70% vs 42%, p50.007) and cavities (48% vs 13%, p,0.001) than HIV-seropositive TB patients. TB patients with a CD4+ T-cell count of #50 cells mm -3 less often had consolidation (33% vs 54%, p50.006) and more often had hilar lymphadenopathy (30% vs 16%, p50.03) compared with patients with CD4 51-200 cells mm -3 . Conclusion: Although different CXR patterns can be seen in TB and non-TB pneumonias there is considerable overlap in features, especially among HIVseropositive and severely immunosuppressed patients. Providing clinical and immunological information to the radiologist might improve the accuracy of radiographic diagnosis of TB.