Hydrogen breath test in schoolchildren.

Abstract
The frequency of negative hydrogen breath tests due to colonic bacterial flora which are unable to produce hydrogen was determined after oral lactulose challenge in 98 healthy Dutch schoolchildren. There was a negative result in 9.2%. The probability of a false-normal lactose breath test (1:77) was calculated from these results together with those from a separate group of children with lactose malabsorption (also determined by hydrogen breath test). A study of siblings and mothers of subjects with a negative breath test did not show familial clustering of this condition. Fecal incubation tests with various sugars showed an increase in breath hydrogen > 100 ppm in those with a positive breath test while subjects with a negative breath test also had a negative fecal incubation test. The frequeny of a false-negative hydrogen breath test was higher than previously reported, but this does not affect the superiority of this method of testing over the coventional blood glucose determination.