1506. Prevalence of Histoplasma Antigenuria among an outpatient Advanced HIV cohort in Kampala,Uganda

Abstract

Abstract Background Histoplasmosis is a major cause of mortality in persons with advanced HIV disease (CD4< 200 cells/mcL) and areas of endemicity are evolving. Presenting symptoms of histoplasmosis may overlap with that of tuberculosis (TB). The true burden of histoplasmosis remains unknown in persons with advanced HIV disease, in part due to poor diagnostic capacity. We sought to evaluate the prevalence of Histoplasma antigenuria among outpatients with advanced HIV disease in Kampala, Uganda. Methods This prospective cohort study of outpatients with advanced HIV in Kampala, Uganda was nested within the ongoing ENCORE trial evaluating preemptive therapy and prophylaxis among outpatients with advanced HIV disease. Urine samples were obtained from participants at the time of enrollment and a Histoplasma galactomannan enzyme immunoassay (EIA) (Immy, Norman OK) was run on urine per manufacturer’s instructions. We obtained baseline characteristics and laboratory values, a statistical comparison by antigen status was not done due to a low number of positives. We calculated the prevalence of histoplasmosis in our cohort using EIA results. We obtained information on symptoms, TB diagnostics, and TB treatment for those with Histoplasma antigenuria. Results We tested 388 urine samples among participants with advanced HIV disease. Four samples were positive for Histoplasma antigen (1%). Baseline characteristics of participants are summarized in Table 1. Histoplasma antigen prevalence among participants with CD4< 100 cells/mcL was 2.5% (4/158). Of those that tested positive for histoplasmosis, the median CD4 count was 39 cells/mcL (interquartile range (IQR): 16–54), and median CRP was elevated at 29 (IQR 14-46). All four participants with Histoplasma antigenuria had a positive TB urine lipoarabinomannan (LAM, AlereLAM, Abbott, Palatine, IL, USA), though only two of four participants reported symptoms of cough, weight loss, and/or physical weakness. Three of four participants with positive Histoplasma antigen were started on anti-TB treatment. Patient symptoms resolved with no intervention. Conclusion Among outpatients with severe advanced HIV disease with CD4< 100 cells/mcL in Kampala, Uganda Histoplasma antigen prevalence was 2.5%. Disclosures All Authors: No reported disclosures