Congenital sucrase-isomaltase deficiency

Congenital sucrase-isomaltase deficiency is a rare inherited gastrointestinal disorder caused by pathogenic variants in the SI gene that lead to deficient or absent activity of the sucrase-isomaltase enzyme complex on the enterocyte brush border This process typically manifests in infancy during the weaning transition to dietary sugars and starches with chronic osmotic diarrhea, abdominal distension, cramping, gas, and subsequent failure to thrive or malnutrition

Congenital sucrase-isomaltase deficiency is a rare inherited gastrointestinal disorder caused by pathogenic variants in the SI gene that lead to deficient or absent activity of the sucrase-isomaltase enzyme complex on the enterocyte brush border Without this dual enzyme, the small intestine cannot properly hydrolyze dietary disaccharides and starch fragments, notably sucrose and isomaltose-derived dextrins, into absorbable monosaccharides

Congenital sucrase-isomaltase deficiency is a rare inherited gastrointestinal disorder caused by pathogenic variants in the SI gene that lead to deficient or absent activity of the sucrase-isomaltase enzyme complex on the enterocyte brush border Without this dual enzyme, the small intestine cannot properly hydrolyze dietary disaccharides and starch fragments, notably sucrose and isomaltose-derived dextrins, into absorbable monosaccharides

Without this dual enzyme, the small intestine cannot properly hydrolyze dietary disaccharides and starch fragments, notably sucrose and isomaltose-derived dextrins, into absorbable monosaccharides

The unabsorbed carbohydrates pass into the colon, drawing water and undergoing bacterial fermentation

This process typically manifests in infancy during the weaning transition to dietary sugars and starches with chronic osmotic diarrhea, abdominal distension, cramping, gas, and subsequent failure to thrive or malnutrition