Human immunodeficiency virus (HIV) infection leads to progressive immunosuppression and the emergence of pulmonary infections such as tuberculosis (TB), disseminated histoplasmosis (DH), and pneumocystosis (PJP), which are major causes of morbidity and mortality among people living with HIV/AIDS (PLWHA). Chest computed tomography (CT) plays a fundamental role in differential diagnosis. This study aimed to analyze clinical and radiological findings in PLWHA with suspected histoplasmosis who underwent urine antigen testing for Histoplasma (LF Miravista®) at a referral center in Salvador, Brazil, between November 2022 and July 2024.

This was an observational, cross-sectional, quantitative study based on secondary data from 63 hospitalized patients with HIV/AIDS and suspected DH. Participants were classified according to the urine antigen test results: positive (DH group) and negative (other opportunistic infections, OIs). Demographic data, ART use, CD4⁺ counts, and CT findings were analyzed.

Among the 63 patients, 27 (42.8%) were diagnosed with DH and 36 (57.1%) with other OIs. Most patients were male, with a higher proportion in the non-DH group (81% vs. 70%). Mean ages were similar (41 vs. 39.2 years). Median CD4⁺ count was lower in the DH group (27 vs. 61.5 cells/mm³). Many patients in both groups were ART-naïve or had discontinued treatment. Common symptoms included fatigue, fever, and weight loss; cough and dyspnea were also reported, with dyspnea being more frequent in DH cases. The most frequent CT findings were micronodules (74% in DH vs. 55.3% without DH), ground-glass opacities (48% vs. 34.2%), and consolidations (37% vs. 44.7%). Lymphadenopathy and macronodules were less frequent. TB was the most frequent OI among non-DH patients (44.4%), and in 55.6% of cases, the etiology remained undetermined. Mortality reached 37% in the DH group and 39% in the non-DH group, with 78.5% of deaths occurring in cases without defined diagnosis.

The clinical and radiological similarity between DH and other OIs limits the diagnostic value of imaging alone. The high rate of undetermined etiologies and elevated mortality highlight the urgent need for wider access to specific diagnostic tests. Integrating clinical, imaging, and laboratory findings, together with early testing and ART adherence, is essential to improve outcomes among PLWHA.