Steatorrhea, effect absorption

R6. Rodriguez-Molina, R., Cancio, M., and Asenjo, C. F., The effect of folic acid on the steatorrhea of tropical sprue and other tests for intestinal absorption. Am. J. Trop. Med. Hyg. 9, 308-314 (1960). 

Interest in the possible connection between intake of fat and absorption of calcium was generated by the concurrent massive losses of calcium in patients with steatorrhea, fatty diarrhea (46, 47). Ordinarily, however, fat is very efficiently absorbed from the gastrointestinal tract. Results of several studies in human adults and children indicate little or no effect of level of dietary fat on absorption of calcium (48-54). However, influence of level of dietary fat on calcium absorption in rat studies has produced conflicting results (55-57). 

Regrettably, the pharmacologist must confess that no drugs exist that can be recommended for the purpose of weight reduction. The so-called appetite suppressants (anorexiants) act only, if at all, for a limited period and are fraught with side effects. Most anorexiants are derivatives of metham-phetamine that have been withdrawn from the market. A different mechanism of action is involved in the case of an inhibitor of pancreatic lipase, which is required in the intestines for fat absorption. This inhibitor (orlistat) diminishes fat absorption so that fats reach the lower bowel, where they can cause disturbances flatulence, steatorrhea, and frequent need to relieve the bowels occur in about 30% of affected subjects. These symptoms correspond exactly to those seen in pancreatic hypofunction which are then usually treated with pancreatic lipase. Before an obese person submits to treatment with orlistat, he or she should voluntarily reduce the food fat content by one half to live free of such unpleasant adverse effects. 

In addition to nutritional inadequacy, vitamin deficiency may result from malabsorption, effects of pharmacological agents, and abnormalities of vitamin metabolism or utilization. Thus, in biliary obstruction or pancreatic disease, the fat-soluble vitamins are poorly absorbed despite adequate dietary intake because of steatorrhea. Absorption, transport, activation, and utilization of vitamins require the participation of enzymes or other proteins whose synthesis is under genetic control. Dysfunction or absence of one of these proteins can produce a disease that is clinically indistinguishable from one caused by dietary deficiency. In vitamin-dependent or vitamin-responsive... 

Because octreotide inhibits many other gastrointestinal hormones, it has a variety of intestinal side effects. With prolonged use, gallbladder and biliary tract complications such as cholelithiasis have been reported. About 5% to 10% of patients complain of nausea, diarrhea, and abdominal pain. Local injection pain occurs with about an 8% incidence. With high doses, octreotide may reduce dietary fat absorption, leading to steatorrhea. 

Deconjugation of bile acids may become excessive when bacterial overgrowth occurs in the small intestine. This condition is referred to as the stagnant loop or blind loop syndrome and is characterized by diarrhea, often accompanied by steatorrhea because of a decrease in the effective concentration of conjugated bile salts and a reduction in the fat-absorptive capacity of the small intestine. 

Bile has long been attributed an important role in medicine [1]. The effect of an impaired bile flow to the intestine has been known to result in steatorrhea — fat malabsorption — and defective absorption of fat-soluble vitamins, notably vitamin K [2], Thus, it is obvious that bile is important for fat assimilation from the intestine. However, it is equally apparent that when fat absorption after bile obstruction or diversion could be studied by quantitative methods, the malabsorption was found to be only partial [3]. In fact, it has seemed surprising that some 60-70% of a normal fat load is absorbed in man and the experimental animal in the absence of bile in the intestine. The absorption of nonpolar lipids, however, is much less efficient, and cholesterol absorption has been reported to have an absolute requirement for the presence of bile salts [4]. Of the bile components important for fat absorption bile salts have been ascribed the main role although experimental results are accumulating regarding the role of bile phospholipids in the specific uptake of sterols by the intestine [5]. 

BILE ACID SEQUESTRANTS Cholestyramine, colestipol, and colesevalam effectively bind bile acids and some bacterial toxins. Cholestyramine is useful in the treatment of bile salt-induced diarrhea, as in patients with resection of the distal Ueum. In these patients, there is partial interruption of the normal enterohepatic circulation of bile salts, resulting in excessive concentrations reaching the colon and stimulating water and electrolyte secretion (see below). Patients with extensive ileal resection (usually >100 cm) eventually develop net bile salt depletion, which can produce steatorrhea because of inadequate micellar formation required for fat absorption. In such patients, the use of cholestyramine will aggravate the diarrhea. 

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