Comparison of an in vitro faecal hydrogen test with the lactulose breath test: assessment of in vivo hydrogen-producing capability in Burmese village children.
In the assessment of carbohydrate malabsorption, it is important to determine if patients with a flat breath hydrogen (H2) response to an absorbable carbohydrate challenge are capable of producing H2. We compared the reliability of a rapid faecal incubation system with the lactulose breath test to assess in vivo H2 production in 64 children. Overall, 70% of subjects were in vivo H2-producers, with breath H2 peaks greater than 10 parts per million within 3 h of ingesting 10 g of the non-absorbable disaccharide lactulose. Faecal specimens from the 64 children had a mean (SE) pH of 5.0 (0.077). Faecal homogenates were incubated with lactulose at both the initially measured faecal pH and at neutral pH. In predicting a normal in vivo H2-producing ability (sensitivity), the faecal H2 test was correct in only 22% (faecal pH) to 44% (pH7) of cases. In predicting an abnormal lactulose breath test result (specificity), faecal homogenate analysis was correct in 53% of cases, at both faecal and neutral pH. These findings indicate that the faecal hydrogen test is unsuitable as a screening test for in vivo H2 production.
Pereira
S P
SP
Gastrointestinal Unit, School of Medicine, University of New South Wales, Sydney, Australia.
Khin-Maung-U
Duncombe
V M
VM
Bolin
T D
TD
Linklater
J M
JM
D001944:Breath Tests; D002675:Child, Preschool; D005243:Feces; D006801:Humans; D006859:Hydrogen / Q000032:analysis / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D007223:Infant; D007792:Lactulose; D002052:Myanmar; D012424:Rural Population
D007792:Lactulose; D006859:Hydrogen