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)

This investigation confirms that 1alpha-hydroxyvitamin D3 (1alpha-OHD3) is a potent drug for the treatment of patients with pseudo-deficiency rickets (Balsan et al., 1975a; Reade et al., 1975; Prader et al., 1976). 1alpha-OHD3 corrects their intestinal malabsorption of calcium and phosphorus, normalizes their serum calcium and phosphate concentrations and promotes healing of skeletal lesions. This study also shows differences in the needs for 1alpha-OHD3 of children with PDR. Three factors appear to be of importance: familial sensitivity, severity of chronic secondary hyperparathyroidism, and periods of increased growth velocity. Tolerance to long-term 1alpha-OHD3 therapy, at doses varying from 0.5 to 2 microgram/d is excellent. Surveillance of patients should include regular measurements of 24 h urinary excretion of calcium, since hypercalciuria is the first signal of overdosage.
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PMID:Long-term therapy with 1alpha-hydroxyvitamin D3 in children with 'pseudo-deficiency' rickets. 20 17

Typical features of hereditary vitamin D-dependent (pseudovitamin D-deficient) rickets were observed beginning at ages 20 and 5 months in a brother and sister. Both had calcium malabsorption correctable with high doses of 25-hydroxyvitamin D. During periods of hypocalcemia they both manifested secondary hyperparathyroidism with hypophosphatemia and high serum concentrations of endogenously produced 1,25-dihydroxyvitamin D. In each, normalization of serum calcium concentration and resolution of osteomalacia were obtained with continuous administration of high doses of ergocalciferol or high doses of 1,25-dihydroxycholecalciferol. Chemical features of vitamin D deficiency were corrected in the presence of high circulating concentrations of 1,25-dihydroxyvitamin D2, produced endogenously, or of 1,25-dihydroxyvitamin D3, administered by mouth. Serum concentrations of 25-hydroxyvitamin D2, 25-hydroxyvitamin D3, 24,25-dihydroxyvitamin D, and 1,25-dihydroxyvitamin D were normal in five first degree relatives. We conclude that in these five first degree relatives. We conclude that in these siblings, rickets and osteomalacia resulted from a hereditary decreased sensitivity to 1,25-dihydroxyvitamin D at the intestine and perhaps other vitamin D target tissues.
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PMID:A familial syndrome of decrease in sensitivity to 1,25-dihydroxyvitamin D. 23 95

Intestinal malabsorption of calcium and the development of osteomalacia in conservatively treated renal failure is explained by a quantitative deficiency of 1,25-dihydroxycholecalciferol, which also contributes to the development of hypocalcaemia. Excess of 25-hydroxycholecalciferol can substitute for this deficiency. The presence and healing of azotaemic osteomalacia is unrelated to the prevailing plasma [Ca] x [P] product. The data suggest that "vitamin D" acts directly on bone mineralisation, but the claim that this apparent effect is normally due to 25-hydroxycholecalciferol is considered unproven. Most of the phenomena of azotaemic osteodystrophy are encountered in simple vitamin D deficiency; as in that condition, deficiency of 1,25-dihydroxycholecalciferol may be of primary significance in causing secondary hyperparathyroidism in renal failure.
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PMID:Vitamin D and the syndromes of azotaemic osteodystrophy. 36 40

Five years following jejunoileal intestinal bypass surgery for obesity, a patient developed debilitating weakness and muscle pain. Osteomalacia was suspected clinically by radiographic and laboratory abnormalities and confirmed by bone biopsy. Malabsorption was documented as well as secondary hyperparathyroidism. Successful treatment of this syndrome with vitamin D and calcium identified a medically reversible disorder which obviated the need for surgical reanastomosis.
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PMID:Osteomalacia and weakness complicating jejunoileal bypass. 43 11

Experimentally diabetic rats have low serum 1,25-dihydroxyvitamin D, intestinal malabsorption of calcium, secondary hyperparathyroidism, and bone loss. To examine the hypothesis that abnormalities similar to those in the diabetic rat might explain human diabetic osteopenia, we studied calcium metabolism in 40 healthy control and 82 diabetic patients aged 18--75 yr [47 untreated: fasting plasma glucose (mean +/- SE), 267 +/- 8 mg/dl; 19 treated but hyperglycemic: glucose 305 +/- 24 mg/dl; 16 treated and in better control: glucose, 146 +/- 8 mg/dl]. Serum total calcium, ionic calcium, immunoreactive parathyroid hormone (Arnaud method, GP-1M and CH-12M antisera), 25-hydroxyvitamin D (Haddad method), and 1,25-dihydroxyvitamin D (Lambert method) concentrations were normal in all 3 groups of diabetics and were not significantly different from values in the control group. We determined absorption of calcium from the intestine by a double isotope method (100 mg Ca carrier; normal range, 40--80%) in 11 control and 13 untreated, uncontrolled diabetics (mean plasma glucose, 285 +/- 17 mg/dl). Absorption of calcium in controls was 60 +/- 3% and in diabetics was 56 +/- 3% (not significantly different). We have found no derangement of calcium metabolism in adults with insulin-requiring juvenile- and adult-onset diabetes regardless of treatment status. The experimental diabetic rat model does not appear to be useful for determining the pathogenesis of adult human diabetic osteopenia.
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PMID:Calcium homeostasis in diabetes mellitus. 46 80

Vitamin D and mineral metabolism were studied in 21 adolescents and young adults with cystic fibrosis and the results were compared to those in 21 matched controls. All CF patients had been maintained on standard multivitamin supplements in combination with pancreatic enzyme replacement. Despite this supplementation, relative to control subjects the CF patients had a 36% reduction in serum 25-hydroxyvitamin D concentration, a slight but significant reduction in serum calcium concentration, evidence of calcium malabsorption with secondary hyperparathyroidism, and a 14% decrease in bone mass measured by the photon absorption technique. Currently accepted modes of pancreatic enzyme replacement and vitamin D supplementation are often inadequate to maintain normal mineral homeostasis in CF patients; additional measurements may be required to reduce the risk of clinically significant osteopenia concomitant with prolonged survival in CF.
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PMID:Reduced serum 25-hydroxyvitamin D concentration and disordered mineral metabolism in patients with cystic fibrosis. 75 19

Chronic renal failure is accompanied by secondary hyperparathyroidism. Inhibition of parathyroid hormone secretion has been reported to be induced by hypomagnesemia in conditions other than chronic renal failure, since severe hypomagnesemia is rare in chronic renal failure. In the case reported here, the patient had chronic renal failure and malabsorption-induced hypomagnesemia; she exhibited hypoparathyroidism while hypomagnesemic, and hyperparathyroidism after magnesium was replaced. Hypomagnesemia induced parathyroid hormone suppression in this patient with chronic renal failure, despite the presence of chronic hyperfunctioning parathyroid cells.
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PMID:Hypomagnesemia. Suppression of secondary hyperparathyroidism in chronic renal failure. 76 31

Obviously, the relentless decrease in bone mass that accompanies aging will continue the long sought "elixir of youth" is discovered. Individuals, because of race, sex, environmental, dietary, genetic or activity differences, will be more or less predisposed to symptomatic osteoporosis with increasing age. The careful and knowledgeable physician should, however, make every attempt to rule out potentially remediable, subtle forms of demineralizing disorders, such as apathetic or T3-thyrotoxicosis, hyperparathyroidism, malabsorption and osteomalacia or multiple myeloma. Not only do these diseases result in an accelerated loss of bone mass and an increased incidence of skeletal fractures but they mimic postmenopausal or senile osteoporosis radiologically. Once the metabolic or malignant disorders of bone metabolism have been effectively considered and ruled out, the senescent or postmenopausal osteoporotic patient should be treated judiciously with short-term estrogen therapy, a diet sufficient in vitamin D and calcium content and continued attempts to insure adequate skeletal mobilization. The addition of sodium fluoride and/or calcitonin to this regimen should not be attempted without extreme caution until the potentially harmful systemic effects of prolonged therapeutic trials have been appropriately assessed.
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PMID:Senile and postmenopausal osteoporosis. 76 91

Previous studies from this laboratory demonstrated that secondary hyperparathyroidism in dogs with chronic renal disease may occur, at least in part, as a consequence of the need for progressive adaptation in renal phosphorus (P) excretion that occurs as glomerular filtration rate falls. However, the studies were of relatively short duration. Moreover, no information emerged regarding a potential role of calcium malabsorption in the pathogenesis of secondary hyperparathyroidism. The short duration of the protocol did not lend itself to the study of the effect of P control or the administration of vitamin D in the pathogenesis of renal osteodystrophy. In the present studies, 14 dogs with experimental chronic renal disease were studied serially for a period of 2 yr. Each animal was studied first with two normal kidneys on an intake of P of 1,200 mg/day. Then, renal insufficiency was produced by 5/6 nephrectomy. The dogs then were divided into three groups. In group I, 1,200 mg/day P intake was administered for the full 2 yr. In group II, P intake was reduced from the initial 1,200 mg/day, in proportion to the measured fall in glomerular filtration rate, in an effort to obviate the renal adaptation in P excretion. In group III, "proportional reduction" of P intake also was employed; but in addition, 20 mug of 25(OH)D(3) were administered orally three times a week. In group I, parathyroid hormone (PTH) levels rose throughout the 2-yr period reaching a final concentration of 557+/-70 U (normal 10-60). In group II, values for PTH remained normal throughout the 1st yr, increased modestly between the 12th and the 18th mo, but then did not rise after the 18th mo. In group III, no elevation of PTH levels was observed at any time; however, these animals were hypercalcemic. Histomorphologic analyses of the ribs of these dogs were performed serially throughout the 2-yr period. A linear relationship was obtained between the osteoclastic resorption surface and the concentration of circulating immunoreactive PTH. The osteoid volume was greater in group I animals when compared to those in group II. None of the morphologic abnormalities associated with renal osteodystrophy were observed in the animals in the third group.
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PMID:Phosphate control and 25-hydroxycholecalciferol administration in preventing experimental renal osteodystrophy in the dog. 87 95

Calcium metabolism was studied in a 12-year-old girl preseting with idiopathic juvenile osteoporosis. Absorption of orally administered 47-Ca was high. Serum calcium and phosphorus, serum immunoreactive PTH and CT and tubular phosphate reabsorption were found to be within normal limits. The data suggest that calcium malabsorption, nutritional calcium deficiency, hyperparathyroidism, a dysfunction related to sex hormones, and Cushing's syndrome cannot be implicated in the aetiology of the osteoporosis in this case who recovered spontaneously with sexual maturation.
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PMID:A case-report of idiopathic juvenile osteoporosis with particular reference to 47-calcium absorption. 89 71


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