High prevalence of Strongyloides stercoralis in people living with HIV: A critical health challenge in the Peruvian Amazon Basin

Otero-Rodriguez S.; Casapia-Morales M.; Pinedo-Cancino V.; Mego-Campos S.; Villacorta-Pezo V.-Y.; Parráguez-De-la-cruz J.; Clark E.H.; Merino E.; Ramos-Rincon J.-M. · PLOS Neglected Tropical Diseases (2025) · DOI: 10.1371/journal.pntd.0013231

Resumen

Introduction Strongyloidiasis is an important but underdiagnosed soil-transmitted helminthiasis, particularly in tropical areas and some vulnerable groups. Objectives To assess the parasitological prevalence, seroprevalence and sociodemographic factors of Strongyloides stercoralis infection in patients living with human immunodeficiency virus (PLWH) in an endemic area. Materials and methods We performed a cross-sectional study of strongyloidiasis in 537 PLWH in two hospitals in Iquitos, Peru, from 20 Oct 2023 to 20 May 2024. We tested patient sera using Strongyloides IgG enzyme-linked immunosorbent assay (ELISA) and stool via the modified Baermann technique and/or charcoal fecal culture as highly sensitive parasitological techniques. We used multivariable logistic regression to identify factors associated with S. stercoralis infection. Results Among the 339 PLWH whose stool samples were collected, 82 were positive for S. stercoralis (prevalence 24.2%; 95% confidence interval [CI] 20.0-29.1%). Among the 534 PLWH whose serum samples were collected, 227 were positive (seroprevalence: 42.5%; 95% CI 38.1-47.5%). The kappa value for charcoal culture and Baermann technique was 0.69. ELISA showed a sensitivity of 92.6% and a negative predictive value of 96.9%. Significant risk factors for stool positivity included living in a rural (unpaved) area (adjusted OR: 1.86), whereas significant risk factors for both stool and seropositivity included living in a poor house (made of wood/leaves) (adjusted odds ratio (ORs): 2.18 and 2.48, respectively), in the Loreto Regional Hospital catchment area (adjusted ORs: 5.66 and 5.37, respectively), or being infected by hookworms in stool (adjusted ORs: 23.88 and 9.78, respectively). Having a low level of studies was associated with seropositivity (adjusted OR 2.42). Conclusion The prevalence of S. stercoralis is high among PLWH in Iquitos, especially among those living in conditions of socioeconomic vulnerability or co-infected with hookworms. The negative predictive value of the S. stercoralis ELISA was high, although this result should be taken with caution in severe immunosuppression.

Instituciones: Universidad Nacional de la Amazonía Peruana