Avaliação da produção de anticorpos IgG e IgE específicos em pacientes alcoolistas infectados por Strongyloides stercoralis

Abstract

Introduction: Strongyloides stercoralis is the primary etiological agent of human strongyloidiasis, infecting approximately 600 million people worldwide, mainly in tropical and subtropical areas. S. stercoralis infections are usually chronic and asymptomatic and may remain undiagnosed for decades. However, in individuals with altered immune responses, such as alcoholics, the infection may evolve into severe forms, such as hyperinfection or dissemination. Objective: To assess the circulating levels of IgG and IgE anti-S. stercoralis antibodies in alcoholic patients and their correlation with cytokine production. Material and methods: The study included 44 alcoholic patients (20 infected and 24 not infected with S. stercoralis) between 20 and 65 years old, with a clinical diagnosis of chronic alcoholism, and treated at the Centro de Acolhimento e Tratamento de Alcoolistas (CATA)/Obras Sociais Irmã Dulce (OSID). It also analyzed 38 non-alcoholic patients (18 infected and 20 not infected with S. stercoralis) assisted at the Laboratório de Análises Clínicas e Toxicológicas da Faculdade de Farmácia (LACTFAR)/Federal University of Bahia (UFBA). The patients in both groups were paired by age and sex. Three methods defined the parasitological diagnosis: spontaneous sedimentation, Baermann-Moraes, and agar plate culture. The enzyme-linked immunosorbent assay (ELISA) detected IgG and IgE anti-S. stercoralis antibodies and determined serum cytokine levels. Results: The ELISAs for detecting IgG and IgE anti-S. stercoralis demonstrated sensitivities of 94.4 and 100% and specificities of 77.8 and 95.0%. Specific IgG production was higher in alcoholic patients infected with S. stercoralis than in infected non alcoholic patients. Although the circulating IL-2 levels in both groups did not show significant differences, there was a positive correlation between specific IgG production and IL-2 levels in alcoholic individuals infected with S. stercoralis (r = 0.402, p = 0.079) and a negative correlation in non-alcoholic individuals infected with S. stercoralis (r = -0.551, p = 0.017). The evaluated cytokines did not present other correlations. Conclusion: This study suggests that alcohol intake synergized with S. stercoralis infection to produce antibodies. Keywords: Strongyloides stercoralis; alcoholics; antibody production; cytokines