Ultrasound evaluation of schistosomiasis-related morbidity among the Xakriabá people in the state of Minas Gerais, Brazil / Avaliação ultrassonográfica da morbidade por esquistossomose mansoni na população indígena Xakriabá, Minas Gerais, Brasil

ABSTRACT

Abstract Objective: To use ultrasound to investigate the morbidity related to schistosomiasis in the Xakriabá indigenous population. Materials and Methods: This was a field-based census study conducted in the territory of the Xakriabá people. A total of 166 individuals were invited, and 148 (≤ 77 years of age) agreed to participate. Most participants underwent abdominal ultrasound, physical examination, and stool examination. Mann-Whitney U and chi-square tests were used for comparisons. We determined risk by calculating odds ratio (OR) and performed logistic regression analysis. Results: Schistosoma mansoni eggs were found in 31 (26.7%) of the 116 stool samples examined, 22 (70.9%) of the 31 being from individuals 4-16 years of age. The median count was 144 eggs/g of feces (interquartile range, 264). Of the 105 participants examined with ultrasound, 68 (64.8%) had hepatomegaly (left lobe), 6 (5.7%) had splenomegaly, and 4 (3.8%) had portal hypertension. Egg-positive stool samples were more common in those with an enlarged left lobe (OR = 3.4; 95% confidence interval (CI) 1.1-11.2; p = 0.043). Periportal fibrosis was found in 30 participants (28.6%), of whom 9 (30%) had pattern C, 10 (33.3%) had pattern D, and 11 (36.7%) had pattern Dc. Age was the only independent risk factor for fibrosis (p = 0.007). Fibrosis was up to nine-fold more common in alcohol drinkers than in nondrinkers (OR = 9.28; 95% CI 2.60-33.06; p < 0.001). Among the 138 participants in whom the clinical form was classified, the chronic hepatic form was identified in 54 (39.1%), of whom 32 (59.2%) were under 30 years of age and one (1.8%) was hepatosplenic. Conclusion: Schistosomiasis in the Xakriabá population is characterized by a high frequency of egg-positive stool samples, predominantly in children/adolescents, and by chronic hepatic form in the young, especially among alcohol drinkers.

RESUMO

Resumo Objetivo: Investigar a morbidade por esquistossomose na população indígena Xakriabá usando a ultrassonografia. Materiais e Métodos: Estudo de campo censitário realizado na terra da população indígena Xakriabá (166 convidados; 148 participantes; idade de 0-77). Foram feitos ultrassonografia abdominal, exame físico e coproscopia (EPF). Os testes Mann-Whitney U e qui-quadrado foram usados para comparações. Foram realizadas análise de risco (odds ratio - OR) e regressão logística. Resultados: De 116 índios com resultado de EPF, 31 (26,7%) tiveram ovos de Schistosoma; 22/31 (70,9%) tinham idade entre 4-16 anos. A carga parasitaria mediana foi 144 ovos/g (intervalo interquartílico 264). De 105 examinados por ultrassom, 68 (64,8%) tiveram lobo hepático esquerdo aumentado, 6 (5,7%) tiveram esplenomegalia e 4 (3,8%) tiveram hipertensão portal. EPF+ foi mais frequente nos indivíduos com lobo esquerdo aumentado (OR 3,4; intervalo de confiança (IC) 95% 1,1-11,2; p = 0,043). Fibrose periportal ocorreu em 30/105 (28,6%) examinados, e desses 30, 9 (30%) apresentavam padrão C, 10 (33,3%) apresentavam padrão D e 11 (36,7%) apresentavam padrão Dc. A idade foi o único fator de risco independente para fibrose (p = 0,007). A fibrose ocorreu até nove vezes mais em usuários de álcool que em não usuários (OR 9,28; IC 95% 2,60-33,06; p < 0,001). Formas crônicas ocorreram em 54/138 (39,1%) participantes, sendo 32 dos 54 (64,8%) em menores de 30 anos; um (1,8%) era hepatoesplênico. Conclusão: A esquistossomose na população Xakriabá caracteriza-se por alta positividade, predomínio em crianças e presença de formas hepáticas crônicas em jovens, especialmente entre usuários de álcool.