Disaccharidase deficiency

This disease, also known as disaccharide intolerance, refers to a series of symptoms and signs that occur when eating foods containing disaccharide due to the lack of disaccharide enzyme at the brush edge of small intestinal mucosa caused by various congenital or acquired diseases, which hinders the digestion and absorption of disaccharide. It can be divided into primary and secondary disaccharidase deficiency, including the deficiency of lactase, sucrase, maltase and trehalase. Lactase deficiency is the most common. Lactase deficiency is also known as lactose intolerance or lactose malabsorption. Lactase can decompose lactose into galactose and glucose. Due to the lack of lactase, patients only have slight disaccharide absorption after eating lactose, and the rest enter the lower part of the small intestine. Bacteria in the intestinal cavity ferment disaccharide to produce organic acids such as lactic acid, carbon dioxide and nitrogen. Unabsorbed disaccharide increases the osmotic pressure in the intestinal cavity and reduces the absorption of intestinal water, resulting in diarrhea. The effect of organic acids on the intestines makes the excretion of acidic feces. Due to excessive gas production, abdominal distension and bowel ringing are caused.