J Pediatr Gastroenterol Nutr. 2018 Jun;66 Suppl 3(Suppl 3):S61-S64.doi: 10.1097/MPG.0000000000001858.

Claudia C Robayo-Torres ^1 2, Marisela Diaz-Sotomayor ¹, Bruce R Hamaker ³, Susan S Baker ⁴, Bruno P Chumpitazi ⁵, Antone R Opekun ⁵, Buford L Nichols ¹

Author information

• ¹Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX.
• ²Pediatric Specialist Network PA, Cypress, TX.
• ³Department of Food Sciences and Whistler Center for Carbohydrate Research, Purdue University, West Lafayette, IN.
• ⁴Digestive Diseases and Nutrition Center, Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY.
• ⁵Department of Pediatrics, Section of Gastroenterology, Hepatology, and Nutrition and Texas Children's Hospital, Baylor College of Medicine, Houston.

Abstract

Background and hypotheses: Human starch digestion is a multienzyme process involving 6 different enzymes: salivary and pancreatic α-amylase; sucrase and isomaltase (from sucrose-isomaltase [SI]), and maltase and glucoamylase (from maltase-glucoamylase [MGAM]). Together these enzymes cleave starch to smaller molecules ultimately resulting in the absorbable monosaccharide glucose. Approximately 80% of all mucosal maltase activity is accounted for by SI and the reminder by MGAM. Clinical studies suggest that starch may be poorly digested in those with congenital sucrase-isomaltase deficiency (CSID). Poor starch digestion occurs in individuals with CSID and can be documented using a noninvasive C-breath test (BT).

Methods: C-Labled starch was used as a test BT substrate in children with CSID. Sucrase deficiency was previously documented in study subjects by both duodenal biopsy enzyme assays and C-sucrose BT. Breath CO2 was quantitated at intervals before and after serial C-substrate loads (glucose followed 75 minutes later by starch). Variations in metabolism were normalized against C-glucose BT (coefficient of glucose absorption). Control subjects consisted of healthy family members and a group of children with functional abdominal pain with biopsy-proven sucrase sufficiency.

Results: Children with CSID had a significant reduction of C-starch digestion mirroring that of their duodenal sucrase and maltase activity and C-sucrase BT.

Conclusions: In children with CSID, starch digestion may be impaired. In children with CSID, starch digestion correlates well with measures of sucrase activity.