Chest Computed Tomography Findings of Disseminated Histoplasmosis in Advanced HIV Disease.

Background: Disseminated histoplasmosis is a severe and often fatal opportunistic infection, particularly among individuals with advanced HIV disease (AHD). Despite its significance, diagnosis is often delayed due to nonspecific clinical and imaging findings, as well as the limitations of classical diagnostic methods.

Objectives: This study aimed to evaluate the chest computed tomography (CT) findings in patients with disseminated histoplasmosis and AHD to provide insights into the radiological patterns associated with this condition.

Patients/methods: A total of 38 patients from a phase II clinical trial on liposomal amphotericin B were included based on the availability of high-resolution chest CT scans. Images were analysed by two radiologists, focusing on lung abnormalities such as nodules, ground-glass attenuation and lymphadenopathy. Clinical presentations, co-infections and other systemic findings were also documented.

Results: The patients were predominantly male (78.9%) with a median age of 37.8 years. Severe immunosuppression was noted, with a median CD4 count of 22 cells/mm³. Pulmonary symptoms were present in 65.8% of patients, while 73.7% reported significant weight loss. All patients had abnormal chest CT findings, with small miliary nodules (89.5%) and ground-glass attenuation (86.8%) being the most common. Large nodules were seen in 73.8% and cavitated nodules in 26.3%. Mediastinal lymphadenopathy was observed in 84.2% of cases, and pleural effusions in 23.7%. Co-infections were detected in 36.8% of the patients.

Conclusions: Chest CT findings in disseminated histoplasmosis are variable and often nonspecific, complicating diagnosis. The presence of diffuse micronodular patterns should raise suspicion for histoplasmosis in endemic regions, particularly among immunocompromised individuals.