Malabsorption
From Wikipedia, the free encyclopedia
Malabsorption is the state of impaired absorption of nutrients in the small intestine. It has many different potential causes. Specific causes lead to different patterns in malabsorption. It may involve fat and fat-soluble vitamins (A, D, E and K); it may also affect vitamin B12, folic acid, iron, protein and carbohydrates. Diarrhea is often present clinically, although this may not be the immediate cause for seeing a physician.
The main purpose of the GI tract is the digestion and absorption of major nutrients (fat, carbohydrate, and protein), essential micronutrients (vitamins and trace minerals), water, and electrolytes. Digestion involves both mechanical and enzymatic breakdown of food. Mechanical processes include chewing, gastric churning, and the to-and-fro mixing in the small intestine. Enzymatic hydrolysis is initiated by intraluminal processes requiring gastric, pancreatic, and biliary secretions. The final products of digestion are absorbed through the intestinal epithelial cells. A defect in any one of these processes may produce a state of malabsorption.
[edit] Causes
- Coeliac disease
- Crohn's disease
- Insufficiency of the pancreas (e.g. after pancreatitis or in cystic fibrosis)
- Whipple's disease (a very rare bacterial infection)
- Malabsorption is a typical aftereffect of gastric bypass surgery, though its severity varies depending on the type of bypass
- Many more
