[Hydrogen (H2) breath test following lactose loading in children with recurrent abdominal pain]

To define the practical diagnostic value of H2 breath testing after lactose load in children with chronic abdominal pain, we measured end-expiratory H2 every 30 minutes for 2 hours after peroral lactose (2 g/kg body weight, Lactoscreen). H2 testing was done in 62 children (28 female, 32 male), aged between 2 and 16 years. Abdominal pain had been observed in these children for more than 2 months. Causes of abdominal pain other than lactose intolerance had been excluded. In 2 out of 62 children, H2 testing was impossible for lack of cooperation. 17 out of the remaining 60 children showed a positive test result (28.3%). In 15 patients, the rise in H2 exceeded 40 ppm, and was thus easily distinguished from a nonspecific rise (less than 25 ppm). Stool pH and Clini-test results were not correlating well with H2 findings, In 16 out of 17 children with positive H2 tests, abdominal pain had ceased on a diet free of lactose after a month. After 6 months 15 out of 17 children were symptom free. These data confirm early indication of non-invasive H2 testing in children with chronic abdominal pain.