Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In an attempt to throw light on the question of age-related variations in the normal blood content of cobalamin and on the frequency of deficiencies of antimegaloblastic nutriments in the elderly, 273 geriatric patients have been investigated. Low serum vitamin B12 values were found in one third of these patients, due to latent pernicious anaemia in five and malabsorption in seven cases, and probably caused by nutritional deficiency of folate or cobalamin in 78 cases. In that part of the series with apparently normal vitamin B12 levels, the mean value (379+/-14 pg/ml) was lower than the mean (456+/-20 pg/ml) for a younger control group. However, this cannot be taken as a sign of a physiological lowering of the cobalamin values with age, as nutritional deficiencies could not be ruled out in this part of the series. It is concluded that serum vitamin B12 assays should be performed rather liberally in the aged. Patients with nutritional deficiency of cobalamin or folate should be treated, even if frank megaloblastic anaemia is not present.
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PMID:Serum vitamin B12 levels in the aged. 98 99

Subtotal pancreatectomy in the rat was performed by a new method. Except for a small remnant along the splenal hilus, the gland was completely removed. Exocrine pancreatic insufficiency was confirmed by fat and nitrogen malabsorption. A moderate diabetes mellitus was seen. Insulin substitution or diet restriction was unnecessary. The absorption of vitamin B12 after oral administration of 10 ng 57CoB12 was 5.0 +/- 0.2 (ng 57CoB12 +/- S.E.M.) in unoperated rats and 5.1 +/- 0.1 in pancreatectomized rats (p greater than 0.5). Pancreatic extract (PE) (100 mg) increased the absorption of 57CoB12 in unoperated rats (p less than 0.01), but not in pancreatectomized rats (p greater than 0.2). PE (300 mg) reduced the absorption in unoperated rats (p less than 0.01). The results indicate that an optimal amount of pancreatic secretion may stimulate the absorption of vitamin B12.
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PMID:The absorption of vitamin B12 after subtotal pancreatectomy in the rat. 99 34

An abundant microbial growth in the small intestine is called "overgrowth syndrome". The dysbiosis existing hereby is to be characterized by the prevailing of certain sorts of germs. A series of typical symptoms is explained by the metabolic activity of microorganisms, in which case disturbances of absorption are uppermost. Morphological and histochemical changes of the intestinal mucous membrane as well as disturbances of the bile acid metabolism and the absorption of carbohydrates, fats and vitamin B12 are explained. Finally the author deals with the microflora in conditions of malabsorption.
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PMID:[Intestinal microbial flora and resorption]. 99 63

Bile acid and vitamin B12 malabsorption were evaluated in 34 cases of ulcerative colitis. Twenty-four patients were non-operated and 10 patients were colectomized. The postprandial duodenal bile acid concentration was abnormally low in 13 of 24 non-operated cases and found to be correlated to the activity of the disease. Two of six patients subjected to colectomy had a reduced bile acid concentration. Bile acid absorption was assessed by the cholyl-glycine-1-14C breath test combined with faecal analysis. The 14C-excretion in breath was abnormally elevated in only one of the patients in the total material. The faecal 14C-output was related to the disease activity in the non-operated group. Patients colectomized for ulcerative colitis had an extremely high excretion of isotope in the ileal effluent, from 15 to 81 per cent of the dose given. The faecal 14C-output was correlated with the duration of the ileostomy and the mass of ileal discharge. Vitamin B12 malabsorption was only present in five patients. It is concluded that patients with ulcerative colitis during the active phase of the disease have bile acid malabsorption, and patients colectomized for ulcerative colitis have an abnormal high bile acid deconjugation in the ileal effluent.
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PMID:Bile acid metabolism and vitamin B12 absorption in ulcerative colitis. 100 50

To identify potentially remediable abnormalities in Crohn disease, 63 patients had evaluations performed for anemia, electrolyte deficiencies, defects of carbohydrate, fat, nitrogen, and vitamin B12 absorption, and jejunal bacterial overgrowth. Ninety percent of the group had two or more potentially correctable defects. More than 50% had anemia associated with iron or folate deficiency of vitamin B12 malabsorption; 33% had low levels of serum sodium, potassium, calcium, or magnesium either singly or in combination; 22% had lactose intolerance, fat malabsorption was persent in 31%; 75% had evidence of disturbed protein metabolism; and bacterial overgrowth of the upper part of the small bowel was identified in 30% of 47 patients.
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PMID:Remediable defects in Crohn disease: a prospective study of 63 patients. 105 64

Diagnosis is often overlooked because symptoms develop slowly and insidiously and many patients don't complain about them. Then too, the giddiness, apathy, confusion, clumsiness, and similar problems may be considered simply signs of "old age." Iron deficiency anemia is the most common type in old people. It's usually due to gastrointestinal bleeding, but there may be a second, less obvious cause. The classic picture of low serum iron, high total iron-binding capacity, and low iron-binding saturation is sometimes distorted. Usually, many studies are needed to confirm the suspicion of a vitamin B12 or folic acid deficiency. A raised mean corpuscular volume in itself signals the need for further investigation. In patients with macrocytosis, the bone marrow must be examined. Tests for intestinal malabsorption must be considered too. Repeated blood tests are essential in patients being treated for any type of anemia. Iron deficiency may hide evidence of folate or B12 deficiency. And iron therapy may lessen bleeding from colonic cancer, delaying diagnosis until it's too late to operate.
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PMID:Anemia--a common but never a normal concomitant of aging. 108 61

Because virtually all cases of vitamin B12 deficiency seen in this country are due to malabsorption, the availability of radioactive vitamin B12 for direct measurement of absorption of this essential nutrient has proved to be of great clinical value. These tests are useful not only in demonstrating vitamin B12 malabsorption but also often in defining the pathophysiological mechanism responsible for this abnormality. The urinary excretion test of Schilling remains the most useful test for vitamin B12 absorption. Minor precautions and modifications in technique make the test results more reliable and easier to interpret. The 8-hr plasma test for vitamin B12 absorption can no longer be considered acceptable. Some patients with vitamin B12 malabsorption have results in the normal range when studied by this method. Serum vitamin B12 assays utilizing radioactive vitamin B12 and the isotope dilution principle are not widely used and are useful screening tests. Low normal or borderline results observed in patients with clinical evidence suggestive of vitamin B12 deficiency should be interpreted with caution or confirmed by radioactive vitamin B12 absorption studies. Radioactive vitamin B12 can also be used for rapid, reliable assay of gastric intrinsic factor, antibody to intrinsic factor and unsaturated vitamin B12 serum. Methods using radioactive folate compounds for similar in vivo and in vitro studies are not yet applicable for routine use in nuclear medicine laboratories.
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PMID:Use of radioisotope techniques in the clinical evaluation of patients with megaloblastic anemia. 109 Sep 98

Vitamin B12 absorption was studied in 34 patients, 10 months to 6 years after construction of a continent ileostomy. Normal Schilling test values (greater than 10 percent) were obtained in 21 of the cases after a single determination. Repeated tests showed a normal B12 absorption in 8 of the 13 patients who had revealed a Schilling test value below 10 percent at the first determination. In the remaining 5 patients, repeated Schilling tests showed borderline values (5-10 percent) in 4 cases and a low value (mean 4.5 percent) in one case. One of the patients with borderline values had previously undergone resection of 80 cm of the terminal ileum. When vitamin B12-intrinsic factor complex was instilled directly into the reservoir in 3 patients, it was found that the vitamin was absorbed by the mucous membrane of the reservoir. The construction of a continent ileostomy reservoir thus does not appear to expose the patient to an increased risk of developing vitamin B12 malabsorption.
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PMID:Vitamin B12 absorption in patients with continent ileostomy. 112 47

Duodenal bile acid concentration following a standard meal, glycine/taurine (G/T) ratio, vitamin B12 absorption, and faecal fat were determined in 79 patients with Crohn's disease. Intestinal resection had been made in 50 patients before the study, and no evidence of recurrence was present at the time of the study. Among 46 patients subjected to ileal resection of 10-180 cm, a reduced duodenal bile acid concentration and vitamin B12 malabsorption was almost invariably present when 50 cm or more of ileum had been removed. Patients with smaller resections and unoperated patients did not show a consistent pattern. Vitamin B12 absorption and duodenal bile acids were of equal value as indicators of ileal dysfunction with the exception that, in 10 ileostomy patients, duodenal bile acids were decreased in every case, but vitamin B12 absorption only when 80 cm of ileum or more had been resected. G/T-ratio was related to the extent of ileal resection-being elevated after large resections (80 cm or more)-but not to the presence of an abnormal flora. Faecal fat was much more elevated in ileostomy patients with large ileal resection (80 cm or more) than in unoperated patients and patients without an ileostomy.
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PMID:The effect of the site of lesion and extent of resection on duodenal bile acid concentration and vitamin B12 absorption in Crohn's disease. 113 25

Since 1964, 41 patients with strictly defined, severe primary (dietetic) protein malnutrition have been studied under metabolic ward conditions during prolonged periods, initially on a low (20 g) and later on a high (100 g) protein diet. Clinical, nutritional, hematological, intestinal absorptive and histological studies were performed in the malnourished state, during and after protein repletion. Classical signs and symptoms of malnutrition, lasting for at least 4 months, were present in most patients. Mild diarrhea was frequent. All were normoblastically anemic, hypoproteinemic, and hypocholesterolemic; serum folate values were normal or low but serum B12 values were normal or high. Liver biopsy showed fatty liver in the cases where it was performed. Mild malabsorption was detected in over one-half of the patients, with moderate intestinal radiological abnormalities. Malabsorption was independent of concomitant folate deficiency. All the clinical, absorptive and histological abnormalities reversed with treatment consisting only of a high protein diet. In addition to protein lack, another factor has to be invoked in the pathogenesis of the intestinal abnormalities present in severely malnourished adults from rural areas in the tropics.
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PMID:Enteropathy in adult protein malnutrition: a review of the Cali experience. 114 51


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