The aim of this study was to evaluate the breath hydrogen test in the diagnosis of small intestine bacterial overgrowth associated with asymptomatic environmental enteropathy in children living in an urban slum. Fifty school-age children living in a slum and 50 children who attended a private health clinic in the same town were included in the study. Breath hydrogen test was carried out after the administration of lactulose or glucose on two different days. Bacterial overgrowth was diagnosed when the hydrogen concentration increased more than 20 ppm in a sample collected for up to 60 min. Production of hydrogen was greater after the ingestion of lactulose than after the ingestion of glucose. Bacterial overgrowth was noted in 37.5% of the children living in the slum and in 2.1% of the control group (P<0.001). The children living in the slum presented a higher proportion of bacterial overgrowth when lactulose was used in the breath hydrogen test.

RESUMO -Estudos realizados há mais de 10 anos demonstraram que a deficiência ontogenética de lactase