title: Breath hydrogen test for detecting lactose malabsorption in infants and children. Prevalence of lactose malabsorption in Japanese children and adults.
abstract: The breath hydrogen test (BHT) was adapted for use in young infants and children. The diagnostic criterion of sugar malabsorption in the BHT was determined by oral administration of 0.5 g/kg of unabsorbable sugar (lactulose) to 21 healthy infants and children. A maximum increase in breath hydrogen less than 0.05 ml/min per m2 was observed in all subjects. A good correlation between results by the BHT and by the ordinary lactose tolerance test was obtained after oral administration of 2 g/kg lactose to 21 healthy infants and children, 2 congenital lactase-deficient infants, and 7 adults. Using this test, 80 healthy Japanese infants and children (aged between one month and 15 years) and 18 adults were examined for lactose malabsorption after a dose of 1 g/kg lactose. All infants and children under 2-years old absorbed lactose completely. The incidence of lactose malabsorption was 30% in 3-year, 36% in 4-year, 58% in 5-year, and 86% in 6-year-old children, 85% in schoolchildren, and 89% in adults. Thus the incidence of lactase deficiency gradually increases with age from 3 years, and about 90% of all normal Japanese adults are lactase-deficient.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001786:Blood Glucose; D001944:Breath Tests / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D006801:Humans; D006859:Hydrogen / Q000032:analysis*; D007223:Infant; D007564:Japan; D007787:Lactose Intolerance / Q000175:diagnosis / Q000453:epidemiology*; D008875:Middle Aged
chemical_list: D001786:Blood Glucose; D006859:Hydrogen