Development and evaluation of diagnostics for visceral leishmaniasis (VL) in HIV patients in elimination settings.

Introduction: People living with HIV (PLHIV) have poor outcomes associated with visceral leishmaniasis (VL), including an increased risk of treatment failure and mortality. The prevalence of asymptomatic Leishmania infection in PLHIV in India remains unknown.
Aim: In this study, led by Médecins Sans Frontières, we aim to determine the prevalence and determinants of asymptomatic Leishmania infection in PLHIV in Bihar, India. We then evaluate methods for detecting asymptomatic Leishmania infection in this cohort.
Methods: A total of 1,296 PLHIV, with no history or symptoms of VL or post kala-azar dermal leishmaniasis, were recruited at anti-retroviral therapy clinics in endemic districts of Bihar between May 2018 and May 2019. Quantitative polymerase chain reaction (qPCR), rK39 enzyme-linked immunosorbent assay (ELISA) and rK39 rapid diagnostic tests (RDT) were carried out on peripheral blood. The Leishmania antigen ELISA was carried out on urine.
Results: The prevalence of asymptomatic Leishmania infection was 7.4% (n=96) as detected by qPCR (0.5%, n=6), rK39 ELISA (7.4%, n=96), and rK39 RDT (0.4%, n=5). An additional 20 (1.5%) participants had Leishmania antigenuria as detected by the Leishmania antigen ELISA, 28 (2.2%) in total. CD4 counts of <100 and 100-199 were found to be determinants of asymptomatic Leishmania infection with odds ratios of 3.1 (95% confidence intervals (CI) 1.2-7.6) and 2.1 (95% CI: 1.1-4.0), respectively.
Conclusion: Asymptomatic Leishmania infection was found to persist in a cohort of PLHIV in India, with patients with low CD4 counts at an increased risk.