RESUMO
AIMS: Tumor necrosis factor alpha (TNF-α) is a proinflammatory cytokine and important mediator of severity for periportal fibrosis (PPF). We hypothesized that the (-G380A) polymorphism in the TNF-α gene is associated with regression of PPF after treatment for schistosomiasis mansoni. METHODS: This is a retrospective cohort study, involving 124 Brazilian patients infected with Schistosoma mansoni, who were followed for 2 years after treatment to estimate the likelihood of PPF regression. Sociodemographic and clinical factors were also identified, with emphasis on specific treatment. RESULTS: No statistical difference was observed between sociodemographic and clinical factors among the exposed groups. Genotypes (-308) GA/AA were positively associated with the degree of PFF regression (relative risk [RR] = 0.52; ρ = 0.025), as well as in the image pattern of PPF (RR = 0.56; ρ = 0.048), when compared with the genotype (-308) GG. There was no statistical difference in TNF-α serum levels between the exposed groups. CONCLUSIONS: These results suggest that the (-G308A) polymorphism of the TNF-α gene may be one of the factors that prevents the regression of the degree and pattern of PPF in the Brazilian population, and thus it may potentially be a predictive factor of PPF intensity in schistosomiasis.