PREVALÊNCIA DE ANTIGENÚRIA DE HISTOPLASMA SP. EM PACIENTES COM HIV/AIDS EM MATO GROSSO DO SUL, BRASIL

Abstract

Histoplasmosis, a fungal infection with high lethality among patients living with HIV (PLHIV) and severe immunosuppression, has been designated by the World Health Organization as a neglected disease of high priority. Significant diagnostic challenges, such as the low sensitivity of conventional and molecular mycological methods, have highlighted the importance of detecting galactomannan from Histoplasma capsulatum in urine samples. This biomarker has proven essential for accurate diagnosis and timely initiation of antifungal therapies, contributing to the reduction of mortality. Currently, this antigen is detected by enzyme-linked immunosorbent assay (ELISA) and, more recently, by immunochromatography, also known as rapid test or lateral flow assay (LFA). These tests also aid in studies of antigenuria prevalence to assess the burden of disease. In PLHIV with suspected disseminated histoplasmosis (DH) in Africa and Latin America, the prevalence of antigenuria ranges from 13% to 26%. This study aimed to evaluate the prevalence of Histoplasma sp. antigenuria in PLHIV with clinical suspicion of HD in a referral hospital in the Central-West region of the state of Mato Grosso do Sul, using the two commercially available methodologies. During one year (2022-2023), 241 patients were clinically evaluated, and 78 with clinical suspicion of HD were included in the study. Urine samples were tested using both ELISA (IMMY-GM CLARUS HISTOPLASMA) and LFA (MIRAVISTA-Lateral Flow) methods. In addition, immunodiagnostic tests for Paracoccidioidomycosis and Histoplasmosis by double immunodiffusion in agar gel, aspergillosis (Platelia IgG, Bio-Rad) and cryptococcosis (CrAg, IMMY) were performed. During the study, 18 of 78 patients (23%) tested positive for H. capsulatum antigenuria, regardless of the test used. Common symptoms included weight loss (66.7%), fever (44.4%), and cough (44.4%); one patient had cryptococcosis as a co-infection, and the case fatality rate was 22%. Among the patients, two had samples that showed fungal growth or tested positive in direct mycological examinations. There was no cross-reactivity with the serological tests evaluated. The concordance between ELISA and LFA was 90%. Our study showed an expected prevalence of H. capsulatum antigenuria and reinforces that LFA may be a viable option for the diagnosis of probable HD in symptomatic PLHIV.