In a prospective study, we investigated whether human immunodeficiency virus (HIV) infection alters the clinical presentation in patients with tuberculous pleuritis. One hundred twelve of 118 patients who presented with pleural effusion suffered from tuberculosis (TB); 65 patients (58%) were HIV seropositive. Evidence of disseminated TB was found more often in HIV-positive than in HIV-negative patients (30.8% vs 10.6%, p < 0.02). Dyspnea, fever, night sweat, fatigue, and diarrhea, severe tachypnea, hepatomegaly, splenomegaly, and lymphadenopathy were significantly more common in HIV-infected than in HIV-negative patients with TB. The same applied to a negative Mantoux reaction, lower hemoglobin, higher beta 2-microglobulin values, and in pleural fluid, lower albumin and higher gamma-globulin levels. Among HIV-infected patients, PPD skin test anergy was significantly associated with relative low albumin and gamma-globulin levels of pleural fluid. However, the radiographic features did not differ with respect to HIV status; they were predominantly those of primary pleuritis (78% in each group). We conclude that coexisting HIV infection affects clinical and laboratory features, but not the radiographic presentation of patients with TB pleuritis in Tanzania.