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)

Eight infants with cow's milk intolerance (CMI) were studied for basal and maximal gastric acid secretion and the fasting serum gastrin level. All these patients had clinical malabsorption. Jejunal biopsies revealed subtotal villous atrophy in six children and slight changes in the remaining two. The mean maximal acid secretion in the infants with CMI was significantly decreased being 85 +/- 78 mumol/h/kg (mean +/- SD), as compared with a control group of the same age with a corresponding value of 233 +/- 66 mumol/h/kg. The fasting serum gastrin level was elevated, being 104 +/- 116 pmol/l in the study group and 37 +/- 10 in the controls. Three infants with CMI underwent gastric biopsy. Marked changes with epithelial degeneration and prominent cellularity in the lamina propria were seen in two patients. The injury was most severe in the antrum of the stomach. When these patients with CMI were treated with human or soy milk, the maximal acid secretion returned normal in six months.
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PMID:Impaired gastric function in children with cow's milk intolerance. 57 86

Four consecutive patients with systemic mastocytosis were studied. One patient had a malabsorption syndrome with only minor histological changes of the intestinal mucosa. Another patient with ulcer diathesis had a gastric secretory pattern resembling Zollinger-Ellison syndrome. Serum gastrin and histamine levels were consistently normal in all patients. Endoscopy of stomach and colon disclosed urticaria-like papulae either spontaneously or after topical provocation in all patients. No increase of mast cells was found in multiple mucosal biopsies. A markedly increased gastric tissue content of histamine was found, however, in the three patients studied. The findings suggest that urticaria-like lesions associated with a high tissue content of histamine may be more important that hyperhistaminaemia in causing the various gastrointestinal symptoms.
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PMID:Gastrointestinal involvement in systemic mastocytosis. 126 81

A modified protein-bound cobalamin absorption test was used to study dietary cobalamin absorption in healthy adults of different age groups and patients with isolated low serum concentrations of cobalamin. Dietary cobalamin absorption was significantly reduced in healthy adults aged 55-75 years compared with young adults, with a further reduction in those older than 75 years. No difference was detected between dietary cobalamin absorption in patients with isolated low serum cobalamin and controls of a similar age group. Cobalamin malabsorption was associated with elevated serum gastrin. The diagnostic value of this protein-bound cobalamin absorption test in the elderly was limited by the frequent finding of reduced absorption in healthy elderly people with normal serum cobalamin concentrations. The performance of such tests should be evaluated in different age groups before application in diagnosis.
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PMID:Protein-bound cobalamin absorption declines in the elderly. 155 Jan 10

After proton pump inhibitors (omeprazole) became available, discussions about safety aspects of (particularly long-term) inhibition of gastric acid secretion have been renewed. In contrast to animals, hypergastrinaemia does not seem to be a relevant problem in man: marginal increases of serum gastrin during proton pump inhibition may induce proliferation of gastric endocrine ("enterochromaffin-like"; ECL-) cells in some cases which are without clinical importance, the risk for development of gastric carcinoids seems negligible if existent at all. Other aspects of acid inhibition (e.g. protein malabsorption, diminished iron and cobalamin absorption, bacterial overgrowth of the stomach, risk of gastric cancer) do also not appear to be of clinical relevance. However, data from larger numbers of patients on long-term therapy with proton pump inhibitors should be available until such treatment can be generally recommended.
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PMID:[Reduction of gastric acid secretion: pathophysiologic and clinically relevant sequelae]. 168 86

Intrinsic factor is produced by the gastric parietal cell. Its secretion is stimulated via all pathways known to stimulate gastric acid secretion: histamine, gastrin, and acetylcholine. There is, however, a different mode of secretion for both substances: atropine, vagotomy, and H2 receptor antagonists inhibit both intrinsic factor and acid secretion, but secretin and the hydrogen-potassium ATPase antagonist omeprazole have no effect on intrinsic factor while substantially reducing acid secretion. Cobalamin in food is bound to animal protein. Cobalamin deficiency due to inadequate dietary intake is rarely seen in extreme vegetarians (vegans). In the stomach cobalamin is liberated from its protein binding by peptic digestion and bound to R-proteins. Hypochlorhydria or achlorhydria, whether medically induced or not, may impair cobalamin uptake. The cobalamin-R-protein complex is split by pancreatic enzymes in the duodenum, where cobalamin is bound to intrinsic factor. Pancreatic insufficiency may lead to cobalamin deficiency. Lack of intrinsic factor is the commonest cause of cobalamin deficiency; very rarely, aberrant forms of intrinsic factor are produced, but the clinical syndrome is similar. Gram-negative anaerobe bacteria bind the cobalamin-intrinsic factor complex, and bacterial overgrowth of the small intestine diminishes cobalamin resorption. Parasitic infections with fish tape-worm and Giardia lamblia are also associated with cobalamin malabsorption. The cobalamin-intrinsic factor complex binds to the ileal receptors in the terminal ileum. Cobalamin absorption may be impaired after resection or by diseases affecting more than 50 cm of the terminal ileum, such as Crohn's disease, coeliac disease, tuberculosis, lymphoma or radiation. There is clearly a wide diversity in the aetiology of cobalamin deficiency, which requires a versatile diagnostic approach.
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PMID:Intrinsic factor secretion and cobalamin absorption. Physiology and pathophysiology in the gastrointestinal tract. 177 33

We examined causes and hematological consequences of low serum cobalamin (vitamin B12) concentration in two representative population samples of 70-year-old (N = 293) and 75-year-old subjects (N = 486). Subjects with values below 130 pmol/liter (4.8% and 5.6%, respectively) were investigated with Schilling test, upper gastrointestinal endoscopy, determination of serum gastrin and group I pepsinogens, and bone marrow examination. Gastrointestinal abnormalities of etiologic significance were found in 26 of the 32 examined subjects: atrophy of the gastric body mucosa (N = 16, with pernicious anemia in six), partial gastrectomy (N = 6), and intestinal malabsorption (N = 4). Megaloblastic hematopoiesis was found in 10 individuals, four of whom had macrocytic anemia. Our results indicate that low serum cobalamin concentration in the elderly is usually a consequence of disease rather than of high age per se and that gastric mucosal atrophy is a major etiologic factor.
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PMID:Low serum cobalamin levels in a population study of 70- and 75-year-old subjects. Gastrointestinal causes and hematological effects. 271 46

The reported incidence of low serum vitamin B12 levels in patients ranges from 4% to 8%. In only a small percentage can this be ascribed to readily diagnosed pernicious anemia, malabsorption syndrome, or to gastrointestinal surgery. This leaves a number of patients in whom the meaning of the low serum B12 is not immediately apparent. In 71 patients with intact gastrointestinal tracts, hematological indices did not adequately separate patients with decreased absorption of unbound B12 from those with normal absorption. A low absorption of B12, either unbound or food-bound, was found, however, when the level of serum gastrin was elevated. In contrast, a normal absorption of unbound B12 was likely (95% of 44 patients) when the serum gastrin was normal.
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PMID:Further studies on the use of serum gastrin levels in assessing the significance of low serum B12 levels. 274 12

In 16 consecutive patients with systemic mastocytosis, we prospectively evaluated a variety of gastrointestinal functions and examined how they relate to the occurrence of gastrointestinal symptoms. Nine patients had either a duodenal ulcer or duodenitis. Hypersecretion of gastric acid was present in 6 patients, and in these patients the mean basal acid output was 20.7 +/- 4.1 mEq/h (range 14-39 mEq/h). Impaired small intestinal absorption occurred in 5 patients, although this was usually mild. The mean fractional emptying rate of liquids for all patients (14.7% +/- 2.3% per minute) did not differ from that for controls (10.7% +/- 0.6% per minute). Mean mouth-to-cecum transit time measured by breath hydrogen testing was the same among patients (87.7 +/- 6.7 min) and controls (86.7 +/- 8.0 min). Plasma histamine concentrations were increased in all patients (mean 1886 pg/ml, range 480-7450) and correlated with the basal acid output (r = 0.64, p less than 0.02) but not maximal acid output or the presence or absence of pain or diarrhea. Mean fasting plasma concentrations of motilin, substance P, and neurotensin from 6 patients did not differ significantly from controls, whereas gastrin and vasoactive intestinal peptide were significantly less than in controls (p less than 0.01). Gastrointestinal symptoms, consisting of abdominal pain or diarrhea, occurred in 80% of patients. Abdominal pain classified as dyspeptic was usually associated with acid-peptic disease of the duodenum and hypersecretion of gastric acid, whereas abdominal pain of a nondyspeptic character was not. Only in those cases of diarrhea consisting of greater than 200 g stool/day was gastric acid hypersecretion frequently found. Neither fecal urgency nor nondyspeptic pain could be accounted for by alterations of gastrointestinal transit. These results demonstrate that gastrointestinal symptoms, peptic disease, and mild malabsorption are much more common than described previously in patients with systemic mastocytosis. Furthermore, the results provide no evidence for the contention that altered gastrointestinal transit is involved in the pathogenesis of these symptoms.
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PMID:Gastrointestinal dysfunction in systemic mastocytosis. A prospective study. 339 14

Achlorhydric atrophic gastritis occurs in approximately 25% of patients with dermatitis herpetiformis (DH). The effect of gluten withdrawal on the gastric condition was studied in 35 patients, with a control group of 20 patients continuing their habitual diet. Gastrointestinal examinations were performed initially and repeated after about 1 3/4 years. Adherence to the diet was confirmed by dietary interviews, improvement of malabsorption test results and intestinal villous structure, and decreased dapsone requirement. Neither the non-restricted diet nor the gluten-free diet had any effect on gastric morphology, the ability to secrete gastric acid, serum gastrin levels, or the frequency or titres of circulating parietal cell antibodies. The findings indicate that gluten is not responsible for the perpetuation of the gastric affection in DH, in contrast to the enteropathy.
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PMID:Influence of gluten-free diet on the gastric condition in dermatitis herpetiformis. 399 62

Malnutrition may cause to the damage intestinal epithelium and pancreas resulting in overt signs of malabsorption syndrome. The diet protein, fats and carbohydrates stimulate secretion, CCK-P, GIP, and gastrin release and effect insulin and HGH release. The amounts of the hormones released depends on intestinal absorption and pancreas secretory function. Therefore, in undernourished children with malabsorption syndrome on impaired function of the hormonal entero-insular axis is likely. In 30 children hormonal component of malnutrition was studied. Digestion and absorption were assayed by glycemic levels and FFA, with hydroxyprolinuria studies following administration of the mixed test meal. HGH and IRI levels were measured following mixed test meal stimulation. Hormonal studies data were correlated with digestion and absorption indices. In undernourished children low levels of HGH and IRI were frequently found. In certain patients with malnutrition the administration of anabolic drugs seems to be advisable.
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PMID:[Food stimulated release of IRI and HGH in children with malabsorption (author's transl)]. 610 40


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