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 the past decade, we have studied four unrelated children with what we believe is a previously unreported disorder affecting the bone marrow and exocrine pancreas. During infancy these patients had the onset of severe, transfusion-dependent, macrocytic anemia plus a variable degree of neutropenia and thrombocytopenia. Their bone marrows had normal cellularity but were characterized by remarkable vacuolization of erythroid and myeloid precursors, hemosiderosis, and ringed sideroblasts. The vacuoles probably represented manifestations of cellular degeneration and death. In two patients, in vitro bone marrow cultures showed abnormal erythroid and myeloid progenitor cell growth and, in one child, abnormal vacuolated erythroid colonies. Family histories were unrevealing, parents were hematologically normal, and both sexes were involved. There was no evidence of specific nutritional deficiencies or exposure to agents associated with marrow vacuolization. A number of therapeutic interventions produced no effect. One child had clinical malabsorption. This child and one other had extensive pancreatic fibrosis at autopsy. The other two patients had findings indicating exocrine pancreatic dysfunction. Two children had splenic atrophy. This new syndrome, with associated bone marrow and exocrine pancreatic dysfunctions, differs in several respects from the syndrome of pancreatic liposis and neutropenia described by Shwachman et all and Bodian et al, and from other conditions with vacuolization of the marrow or sideroblastosis.
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PMID:A new syndrome of refractory sideroblastic anemia with vacuolization of marrow precursors and exocrine pancreatic dysfunction. 50 2

The alimentary surveys carried out on various sectors of the population in industrialized countries have shown the existence of chronic clinically silent deficiency in micronutrients. In some cases, as in folates, their lability against conservation techniques, the change in alimentary habits, the abuse of alcohol and the great quantity of frequently used drugs which interfere in their absorption, diminish their content in the diet and their bio-availability. The appearance of macrocytic anemia is a late deficiency sign, and therefore in situations of an increase need and in patients included in the risk groups, a supplemental intake must be given in order to avoid irreversible lesions if it is not possible to monitor the folate levels. There are risk groups in which various etiological factors come into play, acting at a different metabolic level on the folates and making more difficult their dietetic or pharmacological compensation even if supply is considerably increased. We studied these factors independently and in each specific situation (old people, patients with liver disease, alcoholics, pregnant women and nursing mothers, neonates, children, malabsorption syndromes, gastrectomy, AIDS, anaesthesia and patients being treated with antifolic medication), evaluating their mechanisms of action and their potentiation in determined specific situations.
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PMID:[Folates in human nutrition, Different clinical situations in which folate deficiencies exist]. 176 30

Low serum vitamin B12 levels are not uncommon in the elderly. Patients with vitamin B12 deficiency manifest a spectrum of clinical findings. Pernicious anemia and malabsorption syndrome are the usual causes of vitamin B12 deficiency. Pernicious anemia is confirmed by the presence of intrinsic factor blocking antibody or abnormal results on the Schilling test. Patients with neuropsychiatric symptoms of vitamin B12 deficiency may have a normal Schilling test and no evidence of macrocytic anemia. In such patients, vitamin B12 deficiency is confirmed by determining serum levels of homocysteine and methylmalonic acid.
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PMID:The spectrum of vitamin B12 deficiency. 227 93

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

Inherited disorders of vitamin B12 include those which involve the inability of the vitamin to be absorbed from the gut and transported to the appropriate tissues, and those in which the vitamin is not utilised by target cells. The former include intrinsic factor abnormalities, selective malabsorption of vitamin B12 with proteinuria, and deficiencies of transcobalamin I and transcobalamin II. The latter include a defect in the release of free vitamin B12 from lysosomes (cblF), and defects in the formation of both vitamin B12 cofactors (cblC, cblD) or of adenosyl-B12 (cblA, cblB) or methyl-B12 alone (cblE, CblE variant). This article reviews the major clinical manifestations of these diseases, and provides an approach to the diagnosis of transcobalamin II deficiency and the cbl mutations using cultured cells.
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PMID:Inherited disorders of vitamin B12 metabolism. 333 1

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 39-year-old woman presented with mild anemia, glossitis, an increased MCV, a low serum cobalamin (Cbl) (vitamin B12), mild tissue deficiency of Cbl, but with neither malabsorption of Cbl, impaired intake, nor deficiency of or inactivity of transcobalamin II (TC II). Because of a persistently low holo-TC II (TC II carrying Cbl as the circulating complex of TC II-Cbl), much of the evaluation was focused on the patient's TC II. Her TC II promoted the uptake of Cbl, reacted with anti-TC II, and bound Cbl in vitro. A test dose of 200 micrograms of cyanocobalamin (CN-Cbl) i.m. increased her holo TC II to levels higher than those in healthy persons, but with a much more abrupt fall to a subnormal level. Two milligrams of CN-Cbl i.m. followed by 100 micrograms i.m. monthly failed to maintain normal amounts of circulating TC II-Cbl or to overcome the tissue deficiency of Cbl. One milligram i.m. weekly or daily p.o. corrected both. The low holo TC II was considered to be responsible for the clinical expression and may have been primary to the reduced amounts of total and holo R binder of Cbl in the circulation. This study of a newly recognized defect points out the need for circulating holo TC II, a rational use of pharmacologic amounts of Cbl, and a possible interrelationship between TC II and the R binder of Cbl.
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PMID:A patient with the inability to maintain in vivo levels of bound cobalamin (Cbl) and manifestations of tissue deficiency of Cbl. 395 67

Two siblings with megaloblastic anemia responsive to parenteral vitamin B(12) were studied to elucidate the cause of the B(12) deficiency. Gastric juice from both contained acid and functional intrinsic factor. Serum contained transcobalamin II and lacked antibodies to intrinsic factor. Schilling tests showed vitamin B(12) malabsorption uncorrected by hog intrinsic factor or pancreatic extract. Other parameters of small intestinal function were normal. Proteinuria was initially present in both but cleared in one following treatment with B(12). These patients with "familial selective vitamin B(12) malabsorption" are the first reported from Canada. Only 37 cases have been reported in the world literature to date.
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PMID:Selective vitamin B12 malabsorption in two siblings. 481 48

A case of acquired jejuno-ileal malabsorption complicated by vitamin B12 malabsorption with macrocytic anemia and posterior column dysfunction is reported. Few such observations have been published in the medical literature. In the light of published studies and case-reports the authors review the pathogenic hypotheses concerning the formation of diverticula, the part played by bacterial infection in the mechanisms of malabsorption and the value of antibiotic therapy in the initial treatment of this condition.
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PMID:[Diffuse diverticulosis of the small intestine and malabsorption syndrome. Apropos of a case]. 632 Apr 45

A 27-year-old woman who had undergone extensive small bowel resection at age 14 months developed kyphoscoliosis, ocular palsies, constricted visual fields, retinitis pigmentosa, progressive ataxia, muscular weakness, nearly absent vibration and impaired position sense, areflexia, extensor plantar responses, and macrocytic anemia. Her condition closely resembled Bassen-Kornzweig disease, but lipoprotein electrophoresis was normal. Mild fat malabsorption, lactic acidosis, and severe deficiency of vitamins A and E and carotene were documented. Serum B12 and folic acid levels were normal. During vitamin A and E therapy sufficient to elevate serum levels to the normal range, there was improvement of visual fields and visual acuity in dim light, lactic acidosis, and red cell volume. Progression of symptoms was halted during vitamin replacement therapy, and her gait improved. This syndrome is the human counterpart to vitamin E deficiency in experimental animals.
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PMID:Small bowel resection with vitamin E deficiency and progressive spinocerebellar syndrome. 654 Mar 84


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