P439 Biomarker detection for the diagnosis of disseminated histoplasmosis in people living with HIV/ AIDS in Southern Brazil: a year of implementation

Abstract

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PMBackground: Disseminate histoplasmosis (DH) is an important opportunistic disease in HIV/AIDS patients.Objective: We aimed to report partial results of the implementation of the Histoplasma urinary biomarker as a routine test for the diagnosis of DH in people living with HIV/AIDS (PLWHA) admitted to a reference hospital in Southern Brazil.MethodsThe study was performed in a tertiary hospital, which is recognized as a regional reference center to 21 cities for the treatment of PLWHA. At this service, since the beginning of 2021, a new protocol for DH investigation was adopted, including the systematic execution of urinary antigen test for histoplasmosis (Histoplasma GM EIA, IMMY®) in PLWHA. We retrospectively evaluated data from all of these patients diagnosed with DH in the last 1 year, between March 2021 and March 2022. The study was approved by our university ethics committee (CEP/FURG; N° 234/2018).ResultsWithin the 12 months period, 243 patients from our hospital were investigated by Histoplasma GM EIA through urine samples. A total of 19 were diagnosed with DH through this test, resulting in a prevalence of 7.8%. Interestingly, nine of them were also investigated by antibody detection through immunodiffusion test (IMMY), being all negative in this serology. DH was the AIDS-defining illness in 21% of these patients (4/19), and co-infection with Mycobacterium tuberculosis was detected in 37% (7/19). Half of the patients (11/19) were severe immunosuppressed (CD4 + lymphocytes <100 cells/mm3), 21% (n = 4) had rates between 100 and 200 cells/mm3 and 21% (n = 4) had >200 cells/mm3. The majority of the patients (74%; n = 14) had advanced signs of DH, showing pulmonary impairment, weight loss, fever, neurological, and/or skin lesions and lymphadenopathy, suggesting late diagnosis, 16% (3/19) of the patients had few signs of DH (suggesting precocity), and two patients were diagnosed before the onset of the clinical manifestation, with the strategy of the use of GM Histoplasma EIA as a screening test. Although the antifungal treatment, five of them (35.7%) died.ConclusionThe systematic use of the test to detect a specific biomarker in urine samples had improved substantially the diagnosis of DH in PLWHA in our hospital (19 cases in one year). In addition, since we could diagnose DH with precocity in five patients, we suggest that in regions where DH is hyperendemic, the GM Histoplasma EIA could be used as a screening test for all AIDS patients, similar to what is preconized to cryptococcal disease. More robust studies are instigated to evaluate this strategy, and its benefits to an early diagnosis, resulting in a better quality of life, better prognosis, and consequently reduction of the mortality rate.