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

In order to characterize the mechanism(s) causing vitamin E deficiency during chronic childhood cholestasis, we studied 6 vitamin E-deficient cholestatic children with clinical evidence of neurologic dysfunction (group A), 4 vitamin E-sufficient cholestatic children and young adults with normal neurologic status (group B), and 6 vitamin E-sufficient noncholestatic children (group C). Intestinal absorption of dl-alpha-tocopherol (assessed by an oral tolerance test) was markedly impaired (p less than 0.001) in group A compared with groups B and C, which did not differ from each other. Intraluminal total bile acid concentrations were markedly depressed in group A compared with age-matched controls (0.50 vs. 7.00 mM, p less than 0.001), whereas concentrations were low normal in group B. Intramuscular dl-alpha-tocopherol was well absorbed in 4 group A subjects and corrected abnormal hydrogen peroxide hemolysis. Our data suggest that low intraluminal bile acid concentrations result in malabsorption and deficiency of vitamin E in children with prolonged, severe cholestasis. Intact plasma transport and tissue uptake of vitamin E during cholestasis suggest that intramuscular vitamin E should be utilized for prevention and therapy of the neurologic abnormalities caused by vitamin E deficiency.
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PMID:Mechanism causing vitamin E deficiency during chronic childhood cholestasis. 661 8

Plasma vitamin E levels were found to be decreased (less than 0.5 mg) in thalassemia and in 17 out of 20 patients with Gaucher's disease, where the levels were two standard deviations below the normal mean value. In the latter, the decrease in vitamin E levels correlated with the severity of the clinical expression of the disease and correlated inversely with the degree of hepatosplenomegaly and serum tartrate-resistant acid phosphatase activity. In both diseases, there was no evidence for intestinal malabsorption of the lipid-soluble vitamin. In spite of the different etiology, pathophysiology, and clinical expression, severe vitamin E deficiency could result in both diseases by a common mechanism. In thalassemia, rapid consumption of vitamin E occurs while neutralizing oxidative damage in the pathological erythrocyte membranes and in other tissues. In Gaucher's disease, lysosomal accumulation of glucocerebroside may stimulate phagocytes into a maintained "respiratory burst" with excessive production of oxygen free radicals, resulting in increased utilization and eventual deficiency of vitamin E. Efficacy of antioxidant therapy was evaluated by administration of vitamin E with and without canthaxanthin, which has similar antioxidant properties to beta-carotene, to patients with beta-thalassemia. The results showed increased serum vitamin E levels and a decrease in the extent of erythrocyte lipid membrane peroxidation, while no significant changes occurred in hemoglobin levels and in transfusion requirements.
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PMID:Vitamin E deficiency due to increased consumption in beta-thalassemia and in Gaucher's disease. 675 58

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

The mechanisms and consequences of Vitamin E deficiency were studied in 12 children presenting with chronic cholestasis. Preliminary results indicate that: (1) Vitamin E serum levels are lowest in children with the long-lasting cholestasis and in children in whom fat malabsorption is deepest. (2) Signs of neurologic dysfunction involving peripheral nerves, cerebellum, eye movements and retina were present in 7 children. (3) In vitro study of RBC showed increased hemolysis with oxidating agents and in physiological saline. Degree of hemolysis was inversely related to the serum level of vitamin E. (4) Increased platelet aggregation was observed in 8 patients; 6 of these also had low levels of serum Vitamin E.
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PMID:[Vitamin E and cholestasis in children]. 714 9

The effect of vitamin E deprivation on the fully developed human nervous system is not known. In children with fat malabsorption from various causes neuropathological and neurological changes have been ascribed to vitamin E deficiency. Herein we described a neurological deficit that occurred in a 64-yr-old man with chronic steatorrhea leading to severe vitamin E deficiency. long-term supplementation with vitamin E resulted in clinical improvement beginning a few months after normalization of his vitamin E status.
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PMID:Reversible neurological symptoms caused by vitamin E deficiency in a patient with short bowel syndrome. 714 43

Two adults are described who developed a progressive neurological disorder more than 20 years after the onset of chronic fat malabsorption. The clinical features included dysarthria, cerebellar ataxia, and prominent proprioceptive loss with depressed or absent tendon reflexes. Serum vitamin E was undetectable in both cases. One patient improved clinically and electrophysiologically after oral therapy with vitamin E. The findings in these patients were similar to those in others recently reported with vitamin E deficiency associated with biliary atresia. Electrophysiological observations suggested that the human deficiency state parallels that found neuropathologically in vitamin E-deficient animals.
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PMID:Spinocerebellar degeneration secondary to chronic intestinal malabsorption: a vitamin E deficiency syndrome. 718 49

In 63 patients with malabsorption syndromes, 16 with congenital biliary atresia (BA) and 47 with cystic fibrosis (CF), axonal dystrophy in the gracile nucleus (ADG) was studied. Of the 16 patients with BA, ADG of considerable severity was observed in all 10 over one year of age. Of the 47 patients with CF, it was observed in 32, 61 and 80% of the cases in the first, second, and third decades, respectively. Evidence is presented that there has been a substantial decrease in the incidence of ADG in CF patients in recent years and that the decreased incidence is attributable to vitamin E (Aquasol E) therapy. The beneficial effect of vitamin E supplementation in CF patients is proffered as strong evidence that ADG in BA and CF is related to vitamin E deficiency. The present study indicates that BA and CF patients require vitamin E supplementation to maintain a normal integrity of axons related to the gracile and perhaps other sensory nuclei. Critical neurological evaluation for possible dysfunction of the sensory nuclei in these patients with malabsorption syndromes is advised.
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PMID:Axonal dystrophy in the gracile nucleus in congenital biliary atresia and cystic fibrosis (mucoviscidosis): beneficial effect of vitamin E therapy. 721

Vitamin E levels were measured in the plasma of infants and children with various neuromuscular disorders. Seven of 8 infants with Werdnig-Hoffmann disease (WHD) had a significantly lower plasma vitamin E level (p less than 0.01) than age-matched normal controls, children with congenital myopathies, or children with muscular dystrophy. Vitamin E deficiency in WHD is not caused by malabsorption. A therapeutic trial of vitamin E in 3 patients with WHD did not change the natural course of the disease. Vitamin E deficiency may play a role in the pathogenesis of WHD.
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PMID:Vitamin E deficiency in Werdnig-Hoffmann disease. 729 34

A progressive neurologic syndrome developed in six children with longstanding cholestatic liver disease. The neurologic abnormalities included areflexia, gait disturbance, decreased proprioceptive and vibratory sensation, and paresis of gaze. Serum vitamin E concentrations were uniformly low. Neuropathological studies carried out in two of the three fatal cases revealed degeneration of the posterior column, selective loss of large-caliber, myelinated axons in peripheral nerve, and spheroids in the gracile and cuneate nuclei. These lesions are similar to those found in animals with experimentally induced vitamin E deficiency. We therefore speculate that the neurologic syndrome in these children may be the result of chronic vitamin E malabsorption.
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PMID:A progressive neurologic syndrome in children with chronic liver disease. 745 84

We report a 44-year-old woman in whom intestinal bypass for obesity at age 23 resulted in chronic malabsorption. After hysterectomy for menorrhagia due to atypical endometrial hyperplasia, the finding of myometrial lipofuscinosis led to a demonstration of vitamin E deficiency. Vitamin E supplementation led to an unexpected improvement in the unsteadiness of gait and slurring of speech of which she had also complained. We suggest that supplementation with vitamin E should be routine in all patients with persistent severe steatorrhoea.
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PMID:Symptomatic vitamin E deficiency diagnosed after histological recognition of myometrial lipofuscinosis. 765 82


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