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Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Almost all segments of the gastrointestinal tract have been used as urinary tract substitutes. The specific nutritional and gastrointestinal complications depend on the particular portion of bowel that is removed from the alimentary tract. The use of stomach theoretically may predispose the patient to hypergastrinemia and peptic ulcer disease, hypocalcemia, and iron deficiency or megaloblastic anemia. Resection of a large amount of jejunum causes malabsorption. Limited use of colon segments usually is well tolerated, but loss of large parts of the colon directly decreases available absorptive area, resulting in diarrhea. Resection of the ileum and ileocecal valve can lead to several disease states. One is mixed secretory-osmotic diarrhea. Decreased ileal reabsorption of bile salts results in fat malabsorption and steatorrhea. The presentation of increased amounts of bile salts and fatty acids to the colon decreases water absorption and stimulates active chloride and water secretion, producing a cholera-like high-volume secretory diarrhea. The loss of the ileocecal valve and ileum segment accelerates intestinal transit time, which does not allow for complete digestion and absorption of food. Water and electrolytes remain associated with undigested food particles and may overwhelm the absorptive capacity of the colon, resulting in an osmotic diarrhea. A second problem is vitamin B12 deficiency. Surgical reduction of sites in the terminal ileum for active and exclusive uptake of vitamin B12 might lead to hypovitaminosis. If this is unrecognized, patients may develop irreversible neurologic injury. A third problem is cholelithiasis. Derangements in bile salt metabolism can occur when as little as 10 cm of ileum is resected, and the propensity to form gallstones is increased. Pigment gallstones appear to be the predominant stone associated with ileal resections. The fourth possible problem is urolithiasis, the etiology of which is multifactorial in patients with ileal resections. With decreased availability of bile salts, fat malabsorption occurs. Fatty acids bind with calcium and magnesium to form soaps, resulting in increased levels of free oxalate available for absorption. Moreover, fatty acids directly increase colonic permeability to oxalate.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Nutritional and gastrointestinal complications of the use of bowel segments in the lower urinary tract. 194 6

Twenty-five patients with abdominopelvic malignant tumors receiving irradiation were studied. The following items were assessed before, during, and at the end of the radiation period: 1) clinical symptoms, scored on the basis of their severity; 2) orocecal transit time (lactulose-H2 breath test); and 3) absorption of lactose and bile salts. Ninety-two percent of the patients showed clinical symptoms suggestive of acute radiation enteropathy, mainly diarrhea. A significant acceleration of the orocecal transit was observed during the study: 70 +/- 6.9 min vs 63.3 +/- 6.3 min vs 44.3 +/- 5.1 min (F = 5.49, p = 0.008), being faster in patients with severe diarrhea (F = 3.25, p = 0.05). Forty-four percent and 57% of the patients developed lactose and bile salt malabsorption, respectively. A decrease in the transit time was observed, independent of the absorption or malabsorption of such substances. However, the orocecal transit was faster in those lactose malabsorbers with severe diarrhea, than in those with mild diarrhea (F = 4.2, p = 0.03). The results suggest that acceleration of orocecal transit may be a major factor in the pathophysiology of radiation-induced diarrhea, whereas lactose malabsorption may contribute to the severity of the diarrhea.
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PMID:Acute effects of abdominopelvic irradiation on the orocecal transit time: its relation to clinical symptoms, and bile salt and lactose malabsorption. 196 21

The D-xylose absorption test has been used during the last four decades for evaluation of malabsorption in the small intestine. However, some disagreement still exists about the recommended method of performing this test: the 1-hr blood test, the 5-hr urine test, or both. We evaluated the test by performing 125 combined blood and urine tests in 111 patients. Normal xylose absorption was recorded in both blood and urine in 71 tests (group A, 56.8%). Abnormal test results in both blood and urine were recorded in 29 patients (group B, 23.2%). Only one patient had a pathological blood value and normal xylose excretion in the urine. Twenty-four patients (group D, 19.2%) had normal 1-hr blood xylose (greater than 25 mg/100 ml) with abnormal 5-hr urine xylose (less than 4.5 g/5 hr). Fat and/or bile salt malabsorption were documented in 21 patients (87.5%) of this group using stool fat analysis and the [14C]cholylglycine breath test. These data suggest that in adults the 5-hr urine collection more accurately reflects intestinal absorption in comparison with the 1-hr blood value.
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PMID:D-xylose absorption test. Urine or blood? 198 62

Calcium deficiency appears to play a central role in the development of involutional osteoporosis, especially in Japan, where calcium intake has been traditionally low, never reaching the current recommended daily allowance (RDA) of 600 mg/d. Compromised 1,25(OH)2 vitamin D synthesis in the aging kidney and age-bound changes of the intestine itself lead to calcium malabsorption; in addition, decreasing dietary intake of fat-soluble vitamins and reduced solar exposure associated with inadequate physical activity may contribute to calcium deficiency in old age. High salt intake and increasing protein and phosphate intake tend to aggravate such a tendency. These factors appear to underlie, in part, the widespread use of vitamin D derivatives for the treatment of osteoporosis in Japan. In 1981, a large-scale, double-blind clinical trial established the superior effect of 1 alpha(OH) vitamin D3 in maintaining bone density over that of placebo. The effect of 0.5 micrograms/d 1,25-(OH)2D3 (calcitriol) in two divided doses compared favorably with that of 1 micrograms/d of 1 alpha(OH) vitamin D3 in a recently conducted multicenter, double-blind study on 596 patients with involutional osteoporosis. Spinal fracture rate was also reduced to one-half by administration of the vitamin D derivative for 1 year to 800 patients with osteoporosis.
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PMID:Studies of osteoporosis in Japan. 232 70

Several studies pointed out an altered stool pattern as the most common side effect of auranofin therapy. The major mechanism in the aetiology of auranofin-induced impairment in bowel habit seems to be the inhibition of Na+/K+ ATPase in the gut. In vitro experiments proved that auranofin can affect active bile acid (BA) reabsorption in rat terminal ileum; this action, due to the ability of the drug to reduce Na+ pump activity by inhibiting Na+/K+ ATPase, may make a significant contribution to the auranofin-induced diarrhoea. The ability of auranofin to reduce the Na+ gradient necessary for active BA reabsorption, however, could cause a decrease of serum BA levels in patients taking auranofin before or without the development of an overt diarrhoea. We measured fasting and postprandial serum conjugated BA levels in 10 female rheumatoid arthritis patients before and after one month and two months' auranofin treatment. No patient developed diarrhoea during the chrysotherapy. When oral gold salt therapy was started, we observed a slight decrease in serum BA levels, but difference was not statistically significant. We can conclude that auranofin therapy does not cause BA malabsorption in patients who do not develop diarrhoea during the treatment.
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PMID:Effect of oral gold salt therapy on bile acid absorption in rheumatoid arthritis patients. 233 51

We studied the effects of oral taurine supplementation on bile acids conjugation and duodenal bile salt concentrations in infants. Seventeen infants receiving enteral artificial nutrition were investigated. At the beginning of the study they were 6 to 14 weeks old, in good nutritional state, without malabsorption, protein-losing enteropathy and liver or infectious diseases. After at least 8 days of a stable, taurine-free regimen the infants received oral taurine supplementation (36-45 micromol/kg.24 h) for 8 days. Bile acids were measured before and after each supplementation period in bile samples obtained by duodenal tubing, using enzymatic methods and colorimetry. According to the initial plasma taurine levels before supplementation, the infants were divided into two groups: I) plasma taurine levels less than 60 mumol/l (mean 47 +/-5 mumol/l, n = 8); II) plasma taurine levels greater than 70 mumol/l (mean 77 +/- 2 mumol/l, = 9). After 8 days of taurine supplementation a significant increase of plasma and urinary taurine (P less than 0.01),total duodenal bile salt concentrations (P less than 0.05), total duodenal tauroconjugates (P less than 0.05),taurocholate (P less than 0.01), taurochenodeoxycholate (P less than 0.05), and glycocholate (P less than 0.01), duodenal concentrations, and a significant decrease of the glycoconjugate/tauroconjugate ratio (P less than 0.05), were observed, but only in group I. in group II infants we only noted a significant increase of urinary taurine (P less than 0.01), and of duodenal total tauroconjugates (P less than 0.05). This study shows that the biliary effects of an oral taurine supplementation depends on taurine status and that in taurine-depleted infants intakes of exogenous taurine higher than 45 mumol/kg. 24 h are perhaps necessary for optimal bile salt effects.
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PMID:[Influence of oral taurine supplementation on the intraduodenal concentration and conjugation of bile acids in full-term newborn infants]. 297 13

The purpose of this report is to present an overview on vitamin E distribution, requirements, absorption and biochemical and nutritional aspects. A continuous interest in biochemical functions is recently developed and vitamin E certainly plays an important role throughout the body. The best known of its effects and still actively considered in recent years is the role as an important biological antioxidant. The red blood cell is an ideal model for studying the antioxidant role of vitamin E in cell membranes. Nutritional deprivation is a rare occurrence in developed countries. In prematurely delivered newborns the deficiency is due to marginal stores and to transient malabsorption but it can also be iatrogenic. In infants and adults vitamin E deficiency does occur in syndromes characterized by increased consumption or reduced absorption. Various gastrointestinal disorders induce, with steatorrhoea, marked alteration of vitamin E levels. Cystic fibrosis (CF), the commonest cause of pancreatic insufficiency during the first decades of life, is of particular interest. The fat malabsorption, often severe, may not well respond to pancreatic therapy and the hepatobiliary disease, increased in frequency with improved survival, induce a further reduction in intestinal bile salt concentration. Several manifestations have been attributed to vitamin E deficiency in CF and, although overt neurological complications seem to be relatively uncommon, it is recommended to maintain an adequate supplementation.
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PMID:[Vitamin E: physiology and pathology]. 328 49

Previous studies have provided evidence that an anaerobic bacterium, which degrades dietary oxalate to CO2 and formate, is present in colonic contents of a number of herbivorous species, laboratory rodents and humans. The present study examines the possibility that these bacteria degrade significant amounts of oxalate and can influence colonic oxalate absorption. Guinea pigs adapted to a diet containing 2% sodium oxalate or fed a normal diet were challenged with 67, 135, 170 or 200 mg of sodium oxalate containing 0.5 microCi of [14C]oxalate, which was injected into the cecum. Adapted animals excreted approximately 2% of the 14C in the urine, regardless of the dose, whereas unadapted animals excreted significantly higher amounts in the urine at the two lower doses and died at the two higher doses. Conversely, antibiotic treatment of adapted guinea pigs reduced the ability of their cecal flora to degrade oxalate, and a correspondingly greater percentage of an injected oxalate load was excreted in the urine. Oxalate degradation rates in cecal fluid were depressed by the secondary bile salt deoxycholate, and in vitro studies with pure isolates of guinea pig and human strains of oxalate degraders confirmed that these bacteria were highly sensitive to low concentrations of deoxycholate. Results indicate that these bacteria may be important in preventing excess absorption of oxalate and raise the possibility that the hyperoxaluria associated with bile salt malabsorption of ileal disease in part may be due to suppression of these bacteria by the bile salts.
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PMID:Intestinal oxalate-degrading bacteria reduce oxalate absorption and toxicity in guinea pigs. 337 43

Malabsorption of nutrients in cystic fibrosis (CF) has a multifactorial origin. The factors involved in malabsorption include malfunction of the exocrine pancreas and liver, bile acid metabolism, and disordered intestinal resorptive processes. Therapeutic measures presently employed are only partially effective. Improvement of fat malabsorption is attained by using a pancreatic enzyme supplement consisting of pH-sensitive, enteric-coated microspheres (microsphere preparations) that prevent enzyme degradation in the stomach and travel with the chyme to the small intestine. Microsphere preparations, however, do not improve bile salt deficiency. The detergent Tween-80, given orally to simulate bile salt activity, does not improve fat absorption. The mucus viscosity is probably enhanced in the intestinal epithelium of CF patients and can be decreased by N-acetylcysteine, which breaks down sulfide bonds. However, the addition of a high oral dose of this mucus solvent to pancreatin preparations does not improve fat absorption. Further studies on the disturbed intestinal resorptive mechanism seem warranted since recent investigations point to an abnormal chloride secretion as the primary defect in the intestinal epithelia of CF patients.
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PMID:Malabsorption in cystic fibrosis: mechanisms and treatment. 340 59

In a consecutive series of 107 patients operated on for Crohn's disease involving the distal ileum, the overall incidence of gallstones was 17% and of renal stones 12%. Whereas the frequency of gallstone disease was 9% in patients with minor resections, patients with more than 100 cm diseased or resected small bowel had a frequency of 35%. The probability of gallstone development in both sexes was calculated to be approximately 50% after 20 years of distal ileopathy. The frequency of renal stone disease in patients with minor resection was comparable to that of a population in Sweden but was significantly commoner in patients with resection of more than 100 cm (28%), provided they were not colectomized. The high frequency of stone disease after resection of distal ileum is attributed to metabolic disturbances due to steatorrhea and bile salt malabsorption.
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PMID:Cholelithiasis and urolithiasis in Crohn's disease. 357 31


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