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

Short-chain fatty acids (SCFAs) constitute the major solute fraction of normal stool water and are responsible for the diarrhea associated with carbohydrate (CHO) malabsorption. Although SCFA absorption from the human small bowel has been reported previously, the fate of SCFAs in the colon--their major site of production--was investigated in the present study. The colon of normal volunteers was perfused with neutral, isotonic solutions containing SCFA, 0-90 mM. Propionate was studied in detail with limited observations on acetate and n-butyrate. SCFA absorption was concentration-dependent; back diffusion of metabolic products, ketone bodies, was quantitatively insignificant. The transport process was accompanied by increased Na, K, and water absorption, by luminal alkalinization due to bicarbonate accumulation, and by a fall in lumen PCO2. The results are consistent with the existence of two mechanisms for colonic SCFA absorption: first, nonionic diffusion of protonated SCFA involving consumption of luminal CO2; this process accounts for about 60% of total SCFA absorption; and second, cellular uptake by ionic diffusion of the Na or K salt of the SCFA.
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PMID:Absorption of short-chain fatty acids by the colon. 676 37

The use of a few microcuries of 14C labelled molecules with very short biological half-life for breath-tests gives no more body irradiation than 10 minutes' exposure to the sun. Yet it provides the gastroenterologist with accurate information. Detection and identification of fat malabsorption are easy when 3 labelled lipids are used. Glycine 1 14C cholate administered orally offers a simple, rapid and effective screening technique for the detection of increased bile salt deconjugation and may provide a valuable diagnostic supplement in the study of steatorrhea after ileal resection, bypass or bacterial overgrowth. The clearance of labelled aminopyrine can be decreased in hepatocellular dysfunction or increased in some alcoholic patients or in patients receiving phenobarbitone. Tracer doses of labelled ethanol were used to study the metabolism of ethanol by the liver in alcoholic patients. Chronic ingestion of alcohol stimulates the activity of microsomal drug-metabolising enzymes in both non-cirrhotic and cirrhotic patients; this response is lost in acute liver damage and in chronic alcoholic disease with severe hepatic dysfunction. The CO2-labelled breath-tests are non-invasive, effective and inexpensive. The forthcoming replacement of 14C by non-radioactive 13C or briefly radioactive 11C will render these tests even more attractive.
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PMID:[Labelled CO2 breath-tests in gastroenterology (author's transl)]. 679

Malnutrition and diarrhea constitute a binomial practically inseparable where the factors of the environmental contamination act in a decisive way to trigger the symptoms due to the derangements in the digestive-absorptive process. Fecal flora bacterial overgrowth in the small bowel lumen induces innumerous modification in the intestinal microecology causing morpohological lesions and bile salt deconjugation and all together leads to decrease of the intestinal absorptive surface, glucose malabsorption, and sodium secretion. These morphological and functional derangements due to the unfavorable environmental conditions constitute the picture designated tropical enteropathy, and the intensity of the symptoms are dependent upon various factors including individual susceptibility.
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PMID:Malnutrition and malabsorption. 682 Oct 24

In summary, we propose the following scheme (Figure 5) to describe the role of peroxidation in the pathophysiology of SCA. Sickle erythrocytes are more susceptible to peroxidation than are normal erythrocytes. This increased susceptibility to peroxidation is, in part, due to decreased blood vitamin E levels and abnormal membrane phospholipid organization induced by sickling. The peroxidative damage of sickle erythrocytes may accelerate or contribute to loss of cell deformability and to chronic hemolysis. Peroxidative damage can produce abnormal cellular properties, such as potassium leak and reduced filterability, and contribute to formation of ISCs. Increased red cell rigidity can initiate episodes of capillary obstruction, leading to vasoocclusive painful crises and to tissue infarction. Liver dysfunction as well as increased production of bilirubin secondary to hemolysis could result in bile sludging and decreased secretion of bile salts into the intestinal lumen. Reduced bile salt secretion leads to partial fat and vitamin E malabsorption. Vitamin E deficiency enhances red cell susceptibility to peroxidation and promotes a vicious cycle in SCA. Although we have not studied factors that might initiate peroxidative damage, sickle hemoglobin and excess body iron should be considered as potential sources. Our studies suggest that vitamin E supplementation to sickle-cell patients could be of clinical benefit.
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PMID:Peroxidation, vitamin E, and sickle-cell anemia. 695 61

Bile salt therapy is not used in patients with steatorrhea due to bile salt deficiency because of fear that severe diarrhea would be caused or exacerbated. We report a patient who previously had had colectomy, partial ileectomy, and ileostomy for Crohn's disease. She had severe steatorrhea due to bile salt deficiency and severe diarrhea (the latter apparently due to fatty acid inhibition of electrolyte and water absorption). The diarrhea was improved by loperamide, but severe steatorrhea and malnutrition persisted. The steatorrhea and malnutrition were corrected by ox bile, without an increase in diarrhea. Presumably, the deleterious effect of bile salts per se on small bowel absorption of water and electrolytes was mitigated by correction of fat malabsorption. At least in this patient, bile salt therapy was highly beneficial.
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PMID:Ox bile treatment of severe steatorrhea in an ileectomy-ileostomy patient. 705 48

Three substrates labeled with nonradioactive 13C have been employed to establish a trilogy of noninvasive breath tests to detect fat malabsorption in children and then to differentiate the etiology of the steatorrhea. Administration of 17 mg/kg of (13C)triolein Lipomul (The Upjohn Co., Kalamazoo, Mich.) resulted in a peak excretion rate of 13CO2 greater than 2.7% dose/h in 10 normal subjects (mean value 4.96 +/- 2.2% dose/h) whereas all 17 subjects with fat malabsorption were below this value (mean value, 0.75% +/- 0.63% dose/h); p less than 0.001). For the detection of fat malabsorption, the discriminative value of (13C)triolein was superior, 100% sensitive, and 89% specific, while the use of (13C)palmitic acid (17 mg/kg) or (13C)trioctanoin (7.5 mg/kg) alone yielded both false-positive and false-negative results. In 6 out of 6 cases, pancreatic insufficiency could be differentiated from mucosal disease (7 patients) or bile salt deficiency (4 patients) by the presence of abnormal triolein or trioctanoin breath tests, or both but normal palmitic acid breath tests. However, further differentiation of mucosal disorders from bile salt disorders could not be achieved using either a single- or a multiple-substrate breath test. The use of the single triolein breath test in children offers an attractive, sensitive alternative to conventional fecal fat measurements to establish the presence of steatorrhea, and when using 12C-lipid with multiple substrates, the tests are capable of providing additional insight into the mechanism of fat malabsorption.
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PMID:Diagnosis and differentiation of fat malabsorption in children using 13C-labeled lipids: trioctanoin, triolein, and palmitic acid breath tests. 706 Sep 13

Simultaneous measurements of fecal C-14 and expired 14CO2 in the breath are necessary to evaluate patients with various ileal abnormalities and bile salt malabsorption. Following the oral ingestion of the labeled bile acid, glycine-[I-14C]cholic acid, detection of increased fecal C-14 without abnormal expiration of 14CO2 identifies patients with ileal resection. This contrasts with the normal fecal C-14 content and abnormal expired 14CO2 found in patients with bacterial overgrowth. Fecal C-14 content was determined by utilizing Van Slyke combustion of the specimen and trapping the liberated 14CO2 with Scintisorb C. The method is simple, rapid, and accurate, and expands the diagnostic usefulness of the bile salt absorption test.
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PMID:Measurement of fecal C-14 excretion. 713 Oct 85

In acute diarrhea of infancy we distinguish between infectious and noninfectious causes. In the latter we know some autosomal recessive disorders, e.g. the glucose-galactose-malabsorption, the lactase deficiency as well as the sucrase-isomaltase deficiency. In addition the most frequent acquired disorders like the cow's milk protein intolerance and celiac disease contribute also to the group of noninfectious causes of diarrhea. Here the most effective therapy consists of the elimination of the toxic agent from the diet. In infectious diarrhea we find most frequently rotavirus as the agent but also yersinia, campylobacter fetus, salmonella, shigella, E. coli, lamblia giardia and entameba hystolytica. Generally a conservative treatment with a dietetic regimen is preferred. Only in severe cases with yersinia and campylobacter infection the addition of antibiotic drugs is necessary. Giardia lamblia and amebiasis however have to be treated with metronidazol. As the absorption of glucose is coupled with that of sodium within the small intestine in acute gastroenteritis we find a combined disturbance between salt and carbohydrate absorption. A solution containing glucose and salt is recommended therefore for oral rehydration. The amount administered within the first 24 hours should be between 150-250 ml/kg per day. So called "antidiarrhoic drugs" are questionably effective.
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PMID:[Useful and superfluous measures in the treatment of infant diarrhea]. 717 37

Faecal excretion of labelled bile salts after intravenous injection of carboxyl 14C-cholic acid was normal or low in eleven patients with untreated coeliac disease without diarrhoea. Five other coeliac patients with evident diarrhoea had increased excretion of labelled bile salts, suggesting that bile salt malabsorption may contribute to diarrhoea in coeliac disease.
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PMID:Labelled bile salt excretion and diarrhoea in coeliac disease. 723 71

A study was carried out in the patients with intestinal tuberculosis and obstruction requiring surgery to determine the pathogenesis of malabsorption in this condition. Fifteen of the 20 patients studied had malabsorption, nine of 17 (53%) had intestinal bacterial overgrowth and 10 of 16 (62.6%) had free bile acids in their jejunal aspirates. In a comparable group of nontuberculus intestinal obstruction requiring surgery, six of seven (85.7%) had malabsorption, and four of five (80%) had both the bacterial overgrowth as well as bile salt deconjugation. Among a group of 10 patients with intestinal tuberculosis without significant obstruction, four were found to have malabsorption but only one had evidence of bacterial overgrowth and bile salt deconjugation. In contrast, only one of the 10 patients with extraintestinal tuberculosis and none of the 12 healthy, normal subjects had malabsorption. None had bacterial overgrowth or bile salt deconjugation in either group. Resection of the obstructing lesion corrected the malabsorption as well as the bacterial overgrowth and the bile salt deconjugation in all four patients tested with intestinal tuberculosis. Malabsorption in intestinal tuberculosis thus appears to be associated with obstruction rather than with the tuberculous process. Demonstration of bacterial overgrowth and bile salt deconjugation in the upper small intestine of patients with intestinal tuberculosis with obstruction and malabsorption indicate the presence of a stagnant loop syndrome.
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PMID:A study of malabsorption in intestinal tuberculosis: stagnant loop syndrome. 735 98


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