title: Bowel dysfunction in cystic fibrosis: importance of breath testing.
abstract: OBJECTIVE
  To investigate the prevalence of carbohydrate malabsorption and bacterial overgrowth in children with cystic fibrosis (CF) and abnormal stool pattern referred for breath hydrogen testing.
  
  
  METHODS
  Results from 89 tests using lactose, sucrose and lactulose in 54 children with CF were compared with 5430 tests on children with non-CF-related stool abnormalities.
  
  
  RESULTS
  Children with CF were more frequently unable to ferment lactulose to hydrogen (39% vs. 20%, P<0.03); they had significantly longer oro-caecal transit times (mean 99 vs. 68 min, P<0.0003); they had a higher incidence of bacterial overgrowth (32% vs. 7%, P<0.003) and sucrose malabsorption (47% vs. 14.5%, P<0.004); but they had no increase in lactose malabsorption (40% vs. 31%). Children with bacterial overgrowth in both groups had longer transit times (CF 123 min, non-CF 108 min) compared to the non-CF children without overgrowth (68 min) and reference normal children (69 min).
  
  
  CONCLUSIONS
  Bacterial overgrowth and carbohydrate malabsorption, particularly of sucrose, should be considered when assessing children with CF and abnormal stool patterns.
authors.affiliation: Gastroenterology Unit, Women's and Children's Hospital, North Adelaide, South Australia.
authors.forename: P J
authors.initials: PJ
authors.lastname: Lewindon
authors.forename: T A
authors.initials: TA
authors.lastname: Robb
authors.forename: D J
authors.initials: DJ
authors.lastname: Moore
authors.forename: G P
authors.initials: GP
authors.lastname: Davidson
authors.forename: A J
authors.initials: AJ
authors.lastname: Martin
mesh_terms: D001944:Breath Tests; D050260:Carbohydrate Metabolism; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000150:complications*; D004064:Digestive System / Q000382:microbiology; D005772:Gastrointestinal Transit; D006801:Humans; D006859:Hydrogen / Q000378:metabolism; D007223:Infant; D007410:Intestinal Diseases / Q000150:complications* / Q000209:etiology; D007785:Lactose / Q000378:metabolism; D008286:Malabsorption Syndromes / Q000150:complications* / Q000175:diagnosis; D013395:Sucrose / Q000378:metabolism
chemical_list: D013395:Sucrose; D006859:Hydrogen; D007785:Lactose