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)

The results of all dual isotope tests (2142) carried out on 1989 patients, 807 males (40.6%) and 1182 females (59.4%), during a 10 year period (1976-1985 inclusive) in the Grampian Health Board Area (population 497,272) have been reviewed. Patient age ranged from 5-95 years with 45.5% over 60 years. The referring specialties were Gastroenterology (47.6%), Haematology (11.3%), Paediatrics (2.1%) and all others (39.0%). According to the manufacturer's recommended criteria, results were classified as normal in 1054 (49.2%), abnormal in 659 (30.8%), equivocal in 337 (15.7%) and unsatisfactory in 92 (4.3%) tests. Vitamin B12 malabsorption of ileal type was indicated in 544 tests (25.4%) and of gastric type in 115 (5.4%). Of the latter, 76 were related to pernicious anaemia, 10 to previous gastric surgery and 2 to gastric carcinoma. Of the 337 patients with equivocal results, 138 patients were reviewed and 115 (83.3%) found to have a documented cause for gastric malabsorption (96 pernicious anaemia and 19 previous gastric surgery). In 172 patients with proven pernicious anaemia the manufacturer's recommended criteria for gastric malabsorption were completely satisfied in only 76 (44.3%) but 167 (96.5%) had an excretion ratio greater than or equal to 1.3 and 127 (73.8%) a ratio greater than or equal to 1.7. Unsatisfactory tests were mainly due to incomplete urine collection (91.3%) or contamination with another isotope (5.4%).
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PMID:A survey and critical evaluation of a dual isotope (Dicopac) vitamin B12 absorption test. 292 Jul 38

The pathogenesis of malabsorption has been studied in 70 patients who presented over the age of 65 years and who were referred to a special investigative unit. Often more than one cause was apparent. Fourteen patients had pancreatic insufficiency, most of whom had no history of pain, alcoholism or gallstones. Twenty-three patients had the postgastrectomy syndrome or small-bowel diverticulosis or both. There were eight coeliacs aged 65-72 years at diagnosis. Fifteen patients had an anatomically normal small bowel; eight of these were over 80 years old, and 10 had vitamin B12 deficiency of whom five had confirmed pernicious anaemia. Enterobacterial overgrowth was a feature of all diagnostic groups except pancreatic and coeliac disease. Vitamin B12 deficiency may be an effect of malabsorption, but can also be a cause through impairment of enterocyte function. The association of pernicious anaemia and B12 deficiency with otherwise unexplained malabsorption and bacterial overgrowth suggests that gastric atrophy is a major causal factor in this syndrome, combined in some cases with a 'vicious circle' of B12 malabsorption and deficiency.
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PMID:Causes of malabsorption in the elderly. 309 95

Fractures of the proximal femur are the most dangerous complications of type-II-osteoporosis with a high rate of disability and mortality. In contrast to type-I-osteoporosis, men are affected rather frequently (ratio 1:3). We report on a 79-year old man who was completely in need of care after bilateral fractures of the humerus after having survived a previous pertrochanteric fracture of the left femur. Diagnostic procedures revealed that in this case an intestinal malabsorption has to be taken into consideration as a pathogenetic factor of this severe osteopathy. Bone biopsy confirmed a combination of osteoporosis and osteomalacia. Partial gastrectomy, which had been performed 10 years before, was obviously the reason for malabsorption having caused furthermore pernicious anemia, severe malnutrition and exsiccosis.
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PMID:[Disabling senile osteoporosis]. 323 54

Preferential depletion of corrinoids on transcobalamin II (i.e., sharply reduced holo transcobalamin II (TC II)) occurs early in vitamin B12 deficiency. We measured corrinoids (Cor) and cobalamins (Cbl) on transcobalamins I and III (TC I + III) and on TC II. We also measured the unsaturated B12 binding capacities of transcobalamin I and III and TC II in serum from patients with B12 deficiency (N = 5) (with or without concurrent folate deficiency), with pernicious anemia in remission (N = 7) (1 month after therapy), and in several control groups including healthy volunteers (N = 6), hematologically normal elderly hospitalized patients (N = 5), and non-B12 nonfolate deficient anemic elderly hospitalized volunteers (N = 5). In B12 deficient patients, Cor = 177 +/- 92 pg/ml, Cbl = 56 +/- 20 pg/ml, TC II Cor = 1.0 +/- 2.2 pg/ml, and TC II Cbl = 4.4 +/- 4.9 pg/ml in contrast to pooled controls with Cor = 730 +/- 229, Cbl = 523 +/- 198, TC II Cor = 100 +/- 84, and TC II Cbl = 88 +/- 70 (all values expressed in picograms/milliliters). In pernicious anemia in remission, Cor = 505 +/- 138, Cbl = 294 +/- 77, TC II Cor = 80 +/- 31 and TC II Cbl = 37 +/- 36. TC II unsaturated B12 binding capacity was significantly higher in B12 deficient patients than in pooled controls. These data support that: (a) holo TC II is sharply depleted in untreated B12 deficiency; (b) normally, the only Cor on TC II are cobalamins; (c) in treated pernicious anemia, TC II appears to also bind non-cobalamin corrinoids; (d) continued malabsorption of vitamin B12 may result in reduced B12 on TC II within a month after the last parenteral therapy with 1000 micrograms of cyanocobalamin, and (e) TC II UBBC rises as B12 deficiency is developing. Further investigation is required for definitive delineation of whether sharply reduced Cor on TC II in untreated B12 deficiency can diagnose "true" B12 deficiency, in view of false positive or false negative results which occur in all serum B12 assays.
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PMID:Depletion of serum holotranscobalamin II. An early sign of negative vitamin B12 balance. 334 9

A case of pernicious anemia in a 30 years old men is described. This disease was typical for the hematologic, immunologic and medullary patterns, for his evolution, but the Schilling test, a dual tracer method, did not confirm the diagnosis. The contradictory of this result can be explained wether by the bias of the test itself, or by the intestinal malabsorption due to the vitamin B12 deficiency, or by other factors like bacterial overgrowth state (associated in the pernicious anemia) and a high level of antibodies to intrinsic factor.
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PMID:[The Schilling test in Biermer's disease, problems of false negative reactions. Apropos of a case]. 343 71

Patient records from January 1975 to December 1984 were analysed to assess the possible incidence of protein-bound vitamin B12 malabsorption. This condition is characterised by a low serum vitamin B12 level and a normal Schilling test but impaired absorption of vitamin B12 bound to protein. We found that 48 (25%) patients with a low serum cobalamin level unexplained by other causes had a normal Schilling test. Megaloblastic haemopoiesis was found in 25 of these. From this group, all 10 patients who had a test of protein-bound vitamin B12 absorption showed impaired absorption. Protein-bound vitamin B12 malabsorption may represent an early phase of pernicious anaemia when hypochlorhydria precedes intrinsic factor deficiency and should be tested for when the serum vitamin B12 level is decreased and the Schilling test is normal.
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PMID:Incidence and clinical significance of protein-bound vitamin B12 malabsorption. 359 8

A dual isotope vitamin B12 absorption test in which vitamin B12 is given both in aqueous solution and bound to protein (chicken serum), was evaluated in 26 controls and 68 patients with subnormal serum vitamin B12 concentrations (19 with pernicious anaemia, 13 with iron deficiency, seven after partial gastrectomy, seven with malabsorptive states, five with folate deficiency, four with chronic alcoholism and 13 in whom no cause was apparent). In control patients protein bound absorption decreased with age; isotope excretion was 1.0% or over in those aged under 60 and 0.5% or over in those aged 60 and above. Malabsorption of protein bound vitamin B12 with normal aqueous absorption occurred in five patients with iron deficiency, three with alcoholism, two after partial gastrectomy, two with folate deficiency and in one with a malabsorptive state. In alcoholics abstinence produced an improvement in protein bound absorption. All patients in the group for whom no cause could be found for the subnormal serum vitamin B12 concentration had normal aqueous absorption but four had malabsorption of protein bound vitamin. Although the dual isotope test gave reproducible results and was consistent with the standard Schilling test some anomalies were detected; nine patients had reduced aqueous absorption with normal protein bound absorption. Despite this the dual test may prove useful in determining the importance of a subnormal vitamin B12 concentration where the cause is not clinically apparent. Further development is needed before it can be considered for routine use.
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PMID:Experiences with dual protein bound aqueous vitamin B12 absorption test in subjects with low serum vitamin B12 concentrations. 361 94

Bacterial contamination of the small bowel in the elderly can occur without any anatomical defect, but the importance and pathogenesis of this phenomenon are debatable. We describe two such patients, both with profound vitamin B12 deficiency. Clinical recovery took place without specific treatment of the bacterial overgrowth. In one patient with pernicious anemia, malabsorption of xylose and fat was corrected after vitamin B12 therapy. In the other gastric acidity was normal, but unsuspected mesenteric ischemia led to gangrene of the bowel. In old age there may be more than one explanation for vitamin B12 deficiency and for bacterial overgrowth. Vitamin B12 deficiency within the intestinal cells may be one common factor leading to malabsorption.
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PMID:Small bowel contamination and vitamin B12 deficiency in the elderly. 376 May 23

We performed studies in 25 patients with low serum cobalamin levels who had few if any clinical or hematologic findings of cobalamin deficiency. All but three had morphologically normoblastic hematopoiesis, and 15 were not even anemic. None of those tested excreted methylmalonic acid or homocystine. Nevertheless, the dUST identified metabolic abnormalities in 18 of the 25 cases. In vitro additives were essential in the dUST. Especially noteworthy was MTHF, whose addition unmasked an otherwise undetectable dUST abnormality in four cases. Why MTHF appears to act as a "stress test" in this setting is unknown but deserves further attention. Seven patients had early forms of classical malabsorptive states such as pernicious anemia, defined by abnormal Schilling test results. Among the rest, seven of 13 patients displayed malabsorption of protein-bound cobalamin despite normal absorption of free cobalamin by the Schilling test. In two patients, initially normal Schilling test results became abnormal the following year. These findings demonstrate that seemingly falsely low serum cobalamin levels often indicate subtle biochemical cobalamin deficiency. Early stages of pernicious anemia or other classical malabsorptive states are sometimes responsible for such subtle deficiency. However, malabsorption confined to protein-bound cobalamin is an equally common cause. Current concepts of cobalamin deficiency and the absorptive defects that can cause it should be expanded to include atypical defects requiring newer methods of identification.
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PMID:Atypical cobalamin deficiency. Subtle biochemical evidence of deficiency is commonly demonstrable in patients without megaloblastic anemia and is often associated with protein-bound cobalamin malabsorption. 381 80

The paper reports on a cachectic patient who hitherto was treated as a case of pernicious anaemia. After a 20-year course of the disease a malabsorption syndrome as a result of an atrophic duodenitis was diagnosed.
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PMID:[Differential diagnosis of the malabsorption syndrome]. 403 6


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