Submitted to: Journal of Pediatric Gastroenterology and Nutrition
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/22/2008
Publication Date: 6/1/2008
Citation: Robayo-Torres, C.C., Opekun, A.R., Quezada-Calvillo, R., Villa, X., Smith, E.0., Navarette, M., Baker, S.S., Nichols, B.L. 2008. 13C-breath tests for sucrose digestion in congenital sucrase isomaltase-deficient and sacrosidase-supplemented patients. Journal of Pediatric Gastroenterology and Nutrition. 48:412-418. Interpretive Summary: The small intestinal enzyme sucrase-isomaltase is essential for table sugar digestion. Mutations in the gene are associated with failure to digest sucrose and abdominal pain when foods with sugar are eaten. The diagnosis is based upon demonstrating lack of the enzyme in biopsy samples from the small intestine. Here we used a non-invasive breath-test to confirm the diagnosis and prove that a oral sucrase enzyme supplement fully corrects the deficiency.
Technical Abstract: Congenital sucrase-isomaltase deficiency (CSID) is characterized by absence or deficiency of the mucosal sucrase-isomaltase enzyme. Specific diagnosis requires upper gastrointestinal biopsy with evidence of low to absent sucrase enzyme activity and normal histology. The hydrogen breath test (BT) is useful, but is not specific for confirmation of CSID. We investigated a more specific 13C-sucrose labeled BT. Our goal was to determine whether CSID can be detected with the 13C-sucrose BT without duodenal biopsy sucrase assay, and if the 13C-sucrose BT can document restoration of sucrose digestion by CSID patients after oral supplementation with sacrosidase (Sucraid). Ten CSID patients were diagnosed by low biopsy sucrase activity. Ten controls were children who underwent endoscopy and biopsy because of dyspepsia or chronic diarrhea with normal mucosal enzymes activity and histology. Uniformly labeled 13C-glucose and 13C-sucrose loads were orally administered. 13CO2 breath enrichments were assayed using an infrared spectrophotometer. In CSID patients, the 13C-sucrose load was repeated adding Sucraid. Sucrose digestion and oxidation were calculated as a mean percent coefficient of glucose oxidation averaged between 30 and 90 minutes. Classification of patients by 13C-sucrose BT percent coefficient of glucose oxidation agreed with biopsy sucrase activity. The breath test also documented the return to normal of sucrose digestion and oxidation after supplementation of CSID patients with Sucraid. 13C-sucrose BT is an accurate and specific noninvasive confirmatory test for CSID and for enzyme replacement management.