Monosaccharides malabsorption

The brush border enzymes with disaccharidase and ohgosaccharidase activity are listed in Table 48-1. The sucrase-isomaltase complex comprises most of the sucrase, isomaltase, and maltase (80%) activity of the small intestine. It hydrolyzes sucrose to its constituent monosaccharides, cleaves glucose from a-limit dextrins with 1,6 bonds, and hydrolyzes maltose. The activity of the complex is fourfold to fivefold greater in the jejunum than in the ileum. Changes in diet have a marked effect on the expression of the complex starvation leads to a rapid decline in activity, which is rapidly restored on refeeding. AH small intestinal saccha-ridases may decrease with infection or inflammation of the small bowel to the extent that carbohydrate malabsorption... 

Sucrase-Isomaltase and Trehalase Deficiencies and Monosaccharide Malabsorption... 

Malabsorption of monosaccharides can also cause intestinal symptoms more commonly attributed to maldigestion of disaccharides. Glucose-galactose malabsorption is also inherited as an autosomal recessive trait. Symptoms occur in the affected neonate as soon as milk (lactose) is taken, but also follow ingestion of glucose- or galactose-containing... 

In the case of fat malabsorption, the faeces will contain fat which can be detected by microscopie examination of the stools or by quantitative analysis. Where small molecules such as monosaccharides are not absorbed, they exert an osmotic effect which will prevent water absorption in the large intestine, giving rise to a larne volume of waterv stools. 

Burke, V., and Danks, D. M., 1966, Monosaccharide malabsorption in young infants. Lancet 1 1177. 

Lindquist, B., and Meeuwisse, G. W., 1962, Chronic diarrhea caused by monosaccharide malabsorption, Acta Paediatr. Scand. 51 674. 

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