Clinical Significance of Normal Chest Radiographs Among HIV-seropositive Patients with Suspected Tuberculosis in Uganda

Background And Objective: The frequency, aetiologies and outcomes of normal chest radiographs (CXRs) among HIV-seropositive patients with suspected pulmonary tuberculosis (TB) have been infrequently described.

Methods: Consecutive HIV-seropositive adults hospitalized for cough of ≥2 weeks duration at Mulago Hospital (Kampala, Uganda), between September 2007 and July 2008, were enrolled. Baseline CXRs were obtained on admission. Patients with sputum smears that were negative for acid-fast bacilli (AFB) were referred for bronchoscopy with bronchoalveolar lavage (BAL). BAL fluid was examined for mycobacteria, Pneumocystis jirovecii and other fungi. Patients were followed for 2 months after enrolment.

Results: Of the 334 patients, 54 (16%) had normal CXRs. These patients were younger (median age 30 vs 34 years, P = 0.002), had lower counts of CD4+ T lymphocytes (median 13 vs 57 cells/µL, P < 0.001), and were less likely to be smear positive for AFB (17% vs 39%, P = 0.002) than those with abnormal CXRs. Pulmonary TB was the most frequent diagnosis (44%) among those with normal CXRs, followed by unknown diagnoses, pulmonary aspergillosis and pulmonary cryptococcosis. The frequency of normal CXRs was 12% among pulmonary TB patients. There was a trend towards increased 2-month mortality among patients with normal CXRs compared to those with abnormal CXRs (40% vs 29%, P = 0.15).

Conclusions: Normal CXR findings were common among HIV-seropositive patients with suspected TB, especially those who were young, those with low CD4+ T cell counts and those with sputum smears that were negative for AFB. Mortality was high among those with normal CXRs. Normal CXR findings should not preclude further diagnostic evaluation in this population.