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)

Rickets and osteopenia, common problems in chronic childhood cholestasis, have been attributed to vitamin D malabsorption leading to reduced serum levels of 25(OH)-vitamin D. d-alpha-Tocopheryl polyethylene glycol-1000 succinate (TPGS), a water-soluble form of vitamin E, forms micelles at low concentration. We evaluated the potential role of TPGS in enhancing vitamin D absorption in eight children (aged 5 mo to 19 y) with severe chronic cholestasis (three extrahepatic biliary atresia, three nonsyndromic intrahepatic cholestasis, and two Alagille syndrome). To evaluate vitamin D absorption, the subjects received vitamin D3 1000 IU/kg (maximum dose of 50,000 IU); they then received the same dose of vitamin D3 mixed with TPGS (25 IU/kg). Serial serum vitamin D3 levels and areas under the curve were measured. All patients had enhanced absorption of vitamin D when it was administered in a mixture with TPGS. Mean area under the curve for serum vitamin D3 was 403.0 +/- 83.1 nmol x h/L (155.6 +/- 32.1 ng x h/mL), with a mean rise above baseline of 13.5 +/- 1.8 nmol/L (5.2 +/- 0.7 ng/mL) with vitamin D/TPGS compared with no rise when vitamin D was given alone (both p less than 0.001). Seven patients have been followed for at least 3 mo while receiving the vitamin D/TPGS combination. Those with initially low serum 25(OH)-vitamin D levels (less than 37.5 nmol/L or 15 ng/mL) had normalization (range 37.5-146 nmol/L) within 1 mo, whereas those with initially normal levels remained normal. While the patients were receiving vitamin D/TPGS, serum vitamin E to total lipid ratio either normalized or remained normal.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:d-Alpha-tocopheryl polyethylene glycol-1000 succinate enhances the absorption of vitamin D in chronic cholestatic liver disease of infancy and childhood. 154 43

The action of 1 alpha-hydroxycholecalciferol (oxydevit) was estimated in 204 patients with renal osteodystrophy, osteoporosis of varying etiology, osteomalacia because of malabsorption, congenital rickets-like diseases. The drug was shown to be highly effective in the treatment of secondary hyperparathyroidism in uremia, steroidal and senile osteoporosis. The treatment involved replacement therapy.
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PMID:[Experience in treating metabolic osteopathies with 1 alpha-hydroxyvitamin D3 (oksidevit)]. 181 42

Fractional absorption of calcium was determined in 9 children aged 4.9 to 16.9 yr with chronic cholestatic liver disease to determine the role of calcium malabsorption in the development of metabolic bone disease. Radiological evidence of rickets was absent in all patients, but bone density, measured by single beam photon absorptiometry of the distal radius, was reduced in eight of nine subjects. Serum calcium and phosphorus concentrations were normal in all except one subject. Serum 25-hydroxyvitamin D concentration was decreased compared with controls in only one of nine patients, but serum 1,25-dihydroxyvitamin D concentrations were diminished in seven of nine subjects. In all subjects, dietary calcium and phosphorus intakes were greater than 80% of the RDA. Fractional absorption of calcium, determined by oral and intravenous administration of stable calcium isotopes, was similar in cholestatic compared with control subjects (37.1% +/- 12.5% vs. 34.0% +/- 16.4%). In the cholestatic subjects, calcium absorption correlated with serum 1,25-dihydroxyvitamin D (r = 0.871, p less than 0.002) but not 25-hydroxyvitamin D concentrations. Calcium balance, assessed by the duplicate diet method, was positive in four of five subjects. Anthropometric measurements were performed to examine the relationship between nutritional status and bone mineral content. Heights of all subjects were less than or equal to the 10th percentile and fat stores and somatic protein stores were less than the 25th percentile in six of nine subjects. We conclude that factors other than calcium malabsorption and decreased serum 25-hydroxyvitamin D concentration contribute to diminished bone mass in children with cholestatic liver disease.
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PMID:Calcium absorption in bone disease associated with chronic cholestasis during childhood. 222 18

Deficiency of 3 beta-hydroxy-delta 5-C27-steroid dehydrogenase, the second enzyme in the sequence that catalyses the synthesis of bile acids from cholesterol, leads to chronic liver disease in childhood as well as to malabsorption of fat and fat soluble vitamins. A 4 year old boy with this condition has been successfully treated by oral administration of a bile acid--chenodeoxycholic acid. He had been jaundiced since birth, grew poorly because of rickets, and had severe pruritus. Plasma transaminase activities were persistently raised. Chenodeoxycholic acid 125 mg twice daily for two months, and then 125 mg daily, cured his jaundice and pruritus, returned his transaminase activities to normal, and eliminated the need for calcitriol for prevention of rickets. On this treatment he has so far remained well for two years. A diagnosis of 3 beta-hydroxy-delta 5-C27-steroid dehydrogenase deficiency should be considered in any child with unexplained chronic hepatitis or cirrhosis, especially if the liver disease is accompanied by a clinically obvious malabsorption of fat soluble vitamins. A simple colorimetric test of the urine confirms the diagnosis and effective treatment can be started.
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PMID:Treatment of chronic liver disease caused by 3 beta-hydroxy-delta 5-C27-steroid dehydrogenase deficiency with chenodeoxycholic acid. 224 2

With a normal and varied food intake, the vitamin supply is often sufficient to avoid vitamin deficiency. Since synthetic vitamins have become available, it has become possible to take with one dose the amount of vitamins normally taken up from food in one year. In these pharmacological doses vitamins must therefore be considered as drugs. And in pharmacological doses, their actions are often different and not directly linked to their physiological activity. Two types of pathologic state are unquestionably the concern of vitaminotherapy: More or less specific and intense vitamin deficiencies: Rickets, scurvy, beri beri, pellagra, vitamin deficiency related to alcohol consumption, polyneuritis, encephalopathy, malabsorption, mucoviscidosis, etc. Genetic defects of vitamin metabolism: Prescriptions for these cases represent only a tiny part of the vitamin pharmaceutic market. The prescription of vitamins as adjuvants in other pathologic states without vitamin deficiency, such as neurological pains, psychosis, prevention of common cold, alopecia, anemia, asthenia, carpal tunnel defect, etc., is frequent. The results may be good; however, in some cases, the efficacy is due to chance or placebo effect, and there is no scientific or experimental evidence of beneficial activity. At the moment, the pharmacological vitamin research is very active. New products with vitamin-like structures are being synthesized for specialized therapeutic applications. They will in the near future probably replace elevated and mega-doses for clinical prescription, except, of course, for the treatment of vitamin deficiency. On the other hand, the use of multivitamin preparations in nutritional dosage will greatly increase.
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PMID:Clinical conditions requiring elevated dosages of vitamins. 250 93

There are two sources of vitamin D available to man: The more important source is the cholecalciferol (vitamin D3), which is produced photochemically in the skin from the provitamin, 7-dehydrocholesterol; vitamin D ingested with food is of secondary importance, but assumes a critical role when an individual is deprived of solar exposure. Vitamin D therefore is not strictly a vitamin. A deficiency of vitamin D ultimately results in osteomalacia in adults and rickets in children, and provision of sunlight or small oral doses of the vitamin can cure this bone condition. There are, however, many less common conditions in which small doses of the vitamin are ineffective, whereas larger doses of vitamin D can achieve healing of the bone disease. These conditions are collectively called vitamin D-resistant diseases and include hypoparathyroidism, genetic and acquired hypophosphataemic osteomalacias, renal osteodystrophy, vitamin D-dependent rickets, and the osteomalacia associated with liver disease and intestinal malabsorption. Unfortunately, large doses of vitamin D continue to be prescribed for a wide variety of diseases in which there is little scientific evidence of their efficacy. The benefits and dangers of high doses of vitamin D are discussed and the problems arising from inappropriate or poorly supervised treatment with vitamin D presented. The serum concentration of the active metabolite of vitamin D, 1,25 dihydroxyvitamin D is increased in certain disease states, and the pathophysiology of some these diseases are presented. The exciting developments in tumour differentiation and the role of high doses of 1,25 dihydroxyvitamin D for the control of leukaemia and other blood and skin diseases are discussed.
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PMID:High-dose vitamin D therapy: indications, benefits and hazards. 250 9

An infant with chronic cytomegalovirus hepatitis and a child with atypical Alagille's syndrome had vitamin D deficiency rickets due to malabsorption. Both received ultraviolet irradiation. This treatment corrected biochemical abnormalities and healed the rickets. In the infant use of a sunlamp at home maintained normal 25 hydroxy-vitamin D for over a year. Our study shows that ultraviolet irradiation is an effective treatment of hepatobiliary rickets.
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PMID:Ultraviolet irradiation for hepatic rickets. 254 10

Calcium deficiency causes osteoporosis in experimental animals because the skeleton is sacrificed for the preservation of the plasma (ionic) calcium and to meet obligatory calcium losses in the feces and urine. (Vitamin D deficiency, on the other hand, causes rickets and osteomalacia largely because of the loss of the calcemic action of vitamin D, which leads to hypocalcemia, secondary hyperparathyroidism, and hypophosphatemia.) The concept that human osteoporosis, particularly in postmenopausal women, results from negative calcium balance represents a working hypothesis that fits many, but not all of the available data. In normal women, the crucial event is a rise in obligatory urinary calcium loss, which may result from an increase in the complexed fraction of the plasma calcium, due in turn to an increase in plasma bicarbonate. Prospective trials with calcium supplements have, however, yielded conflicting results. In osteoporotic women, a further increase in urinary calcium combined with calcium malabsorption produces a further increase in bone resorption, but some impairment of bone formation due to declining androgens may constitute an additional risk factor with advancing age. The suppressibility of urinary hydroxyproline by calcium supplementation in those patients who can absorb calcium, and by calcitriol in those who cannot, supports the calcium deficiency model, but more trials are needed to establish its validity.
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PMID:The calcium deficiency model for osteoporosis. 264 3

The level of serum 25-hydroxyvitamin D (25-OH-D3) was determined in 94 cases of healthy volunteers and 98 patients with various diseases. The mean level of the controls was 16.2 +/- 4.6 ng/ml (x /- S). The patients were divided into 5 groups, 1) Osteomalacia and rickets 42 cases, showing typical changes of bone in X-ray films. In 12 of them the disease was caused by vitamin D deficiency. The mean value of 25-OH-D3 was 3.3 +/- 2.0 ng/ml, being much lower than that of controls (P less than 0.001). In 14 cases of hypophosphatemia, 8 cases of renal tubular acidosis and 8 cases of renal insufficiency all complicated with osteomalacia the mean value of 25-OH-D3 was 17.9 +/- 11.4, 18.2 +/- 9.6 and 19.2 +/- 5.6 ng/ml (P greater than 0.05) respectively. 2) Intestinal malabsorption 18 cases. The mean level of 25-OH-D3 was 4.5 +/- 3.2 ng/ml (P less than 0.001). Some of them had hypocalcemia and/or secondary hyperparathyroidism. 2 showed osteoporosis and 1 osteomalacia. 3) Chronic liver disease 24 cases, the mean value of 25-OH-D3 was 6.2 +/- 5.6 ng/ml, being much lower than that of the controls (P less than 0.001). 4) 10 cases after taking anti-epileptic drugs had a mean level of 25-OH-C3 6.9 +/- 5.8 ng/ml (P less than 0.001). 1 had X-ray evidence of osteomalacia. 5) 4 cases of overdosage of vitamin D had a mean value of 110.3 +/- 22.5 ng/ml, being much higher than that of the controls (P less than 0.001). Competitive protein binding assay for measuring 25-OH-D3 is a simple and economic method. It is sensitive and specific as it provides distinct discrimination between healthy controls and patients with vitamin D deficiency or overdosage.
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PMID:[Clinical significance of competitive protein binding assay of 25-hydroxyvitamin D concentration]. 273 43

The interaction between malabsorption syndrome (MAS) and dietary vitamins A and D was studied in broiler chicks reared in floor pens for 4 weeks. The chicks were naturally infected with MAS, whereas hatchmates fed the same diets but in a separate facility (battery brooder) did not exhibit signs of MAS and, therefore, were considered controls. MAS significantly reduced body weights, bone ash, serum calcium and phosphorus concentrations, and liver lipids and increased the incidence of skeletal abnormalities (tibial dyschondroplasia and rickets). Rather than ameliorating the effects of MAS, vitamin A caused a further reduction in body weight and bone ash. A possible nutrient interaction between vitamin A and vitamin D or vitamin E in birds with MAS may account for the exacerbative effect of vitamin A.
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PMID:Exacerbative effect of vitamin A on malabsorption syndrome in chicks. 299 37


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