Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020437 (hypercalcemia)
 10,293 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. In a prospective study of 160 Asian outpatients, plasma calcium, phosphate, alkaline phosphatase, 25-hydroxyvitamin D and parathyroid hormone were compared with a clinical score to determine which measurements singly or in combination were most useful in the detection of osteomalacia. 2. Bone biopsies were performed in 45 of 48 patients considered to be at risk of osteomalacia. Of the 39 quantifiable bone biopsies, nine showed unequivocal osteomalacia, 13 were judged to be borderline and 17 biopsies were normal. 3. The clinical score was highly sensitive, identifying eight of nine patients with osteomalacia, but not specific, six of 17 normal patients having an abnormal score. 4. Plasma parathyroid hormone was the best single biochemical test for identifying osteomalacia. By using a discriminant function based on parathyroid hormone and alkaline phosphatase, it was possible to classify 96% cases correctly; a discriminant function utilizing calcium, phosphate and alkaline phosphatase was successful in 85% of cases. It was not possible to discriminate between histological groups on the basis of plasma 25-hydroxy-vitamin D values. 5. We confirm that the clinical score is a useful and inexpensive screening test for osteomalacia in British Asians. In those patients with an abnormal score we suggest that parathyroid hormone and alkaline phosphatase are measured. Where both parathyroid hormone and alkaline phosphatase are high, in the absence of hypercalcaemia, histological osteomalacia is extremely likely.
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PMID:Detection of osteomalacia in British Asians: a comparison of clinical score with biochemical measurements. 216 Mar 56

Vitamin D in large doses is a proper therapy in hypoparathyroidism, osteomalacia, vitamin D-resistant rickets and also in chronic renal failure although in those cases the active metabolite of vitamin D is preferred because of the much shorter biologic halflife. Apart from these disorders there are no good reasons for using megadoses of vitamin D. Pseudo-vitamin D intoxication is caused by granulomatous diseases as a so-called inappropriate calcitriol secretion. In cases of vitamin D intoxication the 25-OHD3 content in the serum is much too high, the parathyroid hormone concentration is suppressed and the I,25-(OH)2D3 level is low, whereas in pseudo-vitamin D intoxication the 25-OHD3 content in the serum is normal and the I,25-(OH)2D3 is seriously elevated. Cultured alveolar macrophages of patients with sarcoidosis can produce I,25-(OH)2D3 as can sarcoid lymph node homogenate. I,25-(OH)2D3 proved to promote the fusion of alveolar macrophages to form polykaryons. Local concentrations of I,25-(OH)2D3 may be higher at sites of granulomatous tissue and can act in a paracrine or autocrine fashion to enhance granuloma formation. The action of glucocorticoids and chloroquine in patients with sarcoidosis and hypercalcaemia is presumably an interruption of the described vicious circle.
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PMID:[Vitamin D poisoning; real and spurious]. 223 47

Hypercalcemia, due to autonomous functioning of the parathyroids following long standing secondary hyperparathyroidism, is a well known complication in patients with renal osteodystrophy, which can on most cases be treated by parathyroidectomy only. While patients with renal osteodystrophy react favorably to supplementation of active vitamin D metabolites to prevent or reverse renal osteodystrophy, the use of these drugs is bound to result in greater hypercalcemia in those patients who are already hypercalcemic. The question rose if the bisphosphonate amino hydroxypropylidene bisphosphonate (APD) would decrease plasma calcium concentration sufficiently in order to create room for the use of vitamin D to cure the osteomalacia component of the osteodystrophy and simultaneously block the excessive bone resorption. Therefore, five patients with renal osteodystrophy and hypercalcemia were treated for up to 9 months with APD. Three of them, who were on chronic hemodialysis, received 15 mg APD i.v. 3 times a week, the 2 other patients with severe renal failure received 200 mg APD orally. Ionized calcium in plasma did not decrease. Histological investigation of bone samples, obtained before and after therapy, showed an increase of fibrous tissue and a remarkable increase in the number of osteoclasts or osteoclast-like cells not only along the bone-margin, but mainly within the bone-marrow. We conclude that in patients with renal failure with hypercalcemia, APD in the doses used had no effect on plasma calcium level, but caused a striking change in bone histology. Although the consequences of these findings are not yet clear, they do not seem to indicate improvement of bone structure.
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PMID:No effect of APD (amino hydroxypropylidene bisphosphonate) on hypercalcemia in patients with renal osteodystrophy. 233 26

Forty-one patients in chronic end-stage renal failure and 4 patients with a functioning kidney transplant presented with spontaneous hypercalcemia or intolerance to vitamin D3 sterols and/or oral calcium supplements. Bone iliac crest biopsy with aluminum staining and Tc-pyrophosphate bone scintigraphy with determination of Fogelman score were performed in all cases. Two patients had aluminum-induced osteomalacia (AL O). Thirty-eight biopsies showed renal osteodystrophy (secondary hyperparathyroidism or various combinations of osteitis fibrosa and osteomalacia): 19 with positive staining for aluminum (RO + AL) and 19 without aluminum deposits (RO). The series also comprised 2 cases of pure osteomalacia (OM), 2 cases of osteoporosis (OP), and 1 case of osteoporosis with aluminum accumulation (OP + AL). Mean Fogelman score in RO patients (9.1 +/- 0.3) was significantly higher than in all other categories (5.9 +/- 0.5 for RO + AL, and scores ranging from 0 to 8 in the last 7 patients, p less than 0.01). Patients with massive aluminum accumulation in bone (greater than 75% of the total trabecular surface) showed no or very low uptake of the isotope by the skeleton. Fogelman scores of 9 or higher were always associated with histological secondary hyperparathyroidism. 99mTc-pyrophosphate bone scintigraphy is helpful to distinguish aluminum intoxication from secondary hyperparathyroidism in uremic patients.
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PMID:Differential diagnosis between secondary hyperparathyroidism and aluminum intoxication in uremic patients: usefulness of 99mTc-pyrophosphate bone scintigraphy. 254 46

Metal ions have various and significant effects on the skeletal system. Aluminum accumulation in renal dialysis patients causes osteomalacia, while gallium is an effective therapeutic agent for treating the hypercalcemia accompanying certain malignancies. Using in-vitro systems that stimulate in-vivo mineralization, the authors have investigated the physical-chemical mechanisms of the actions of aluminum and gallium and report some of their findings.
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PMID:The effect of aluminum and gallium ions on the mineralization process. 255 41

The author examined a group of 143 patients with osteomalacia of different origin before treatment and after adequate treatment with vitamin D, using laboratory tests, assessment of body weight and muscular strength (grip of the dominant hand). After treatment there was a significant rise of calcaemia, phosphataemia and calciuria and a drop of alkaline phosphatase activity. The body weight increased within the first month of treatment on average by 1.27 kg, during the second month by another 1.15 kg. The patients gained a total of 2.42 kg. The muscular strength increased during the first month on average by 3.23 kg and during the second month by another 2.16 kg, i.e. a total of 5.39 kg. From these results it may be concluded that vitamin D may have a certain anabolic effect if used in pharmacological does either due to an increased nutrient absorption from the gut because of hypertrophy of the intestinal wall or indirectly via hypercalcaemia which increases the hydrochloric acid secretion in the stomach as well as pepsin secretion, and promotes activation of trypsin and lipase in the duodenum and moreover causes retardation of the intestinal transit. The increased muscular strength in due to a rise of calcaemia, improved muscle contraction and probably also due to the mentioned nutritional factors. There may be also the factor of an improved lifestyle due to the immunomodulating action of vitamin D and disappearance of bone pain.
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PMID:[Anabolic effects of vitamin D in patients with osteomalacia]. 263 59

Clinical investigations have shown that 1 alpha-hydroxycholecalciferol (oxydevit, alphacalcidiol) and 1 alpha, 25-dihydroxycholecalciferol (rocaltrol) are act vitamin D3 agents producing a positive clinical effect in different types of osteoporosis and osteomalacia. Clinical improvement of the patients' status (alleviation of the pain syndrome, an increase in motor activity) was noted in 1-2 mos., an x-ray picture of regeneration of the bone structure of both axial and peripheral skeleton--in 6-12 mos. after the initiation of therapy. Therapy was attended by an increase in the serum content of total and ionized calcium, the return of alkaline phosphatase activity to normal, and a decrease in the level of parathormone. During prolonged therapy these agents administered at daily doses of 0.25-2 micrograms caused no pathological side-effects and hypercalcemia. In osteoporotic conditions all these drugs were equal in their clinical effectiveness. Rocaltrol has some advantages in the presence of associated liver pathology.
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PMID:[Comparative evaluation of the effectiveness of vitamin D3 preparations (1-alpha-hydroxy- and 1-alpha,25-dihydroxycholecalciferol in various forms of osteoporosis and osteomalacia]. 276 60

Five patients with symptomatic osteomalacia undergoing chronic hemodialysis took 24R,25-dihydroxycholecalciferol, 10 micrograms/day, for periods of 6-20 months. Four patients took calcitriol simultaneously in doses consistent with normocalcemia, but the 5th was unable to do so because of recurrent hypercalcemia. In the group as a whole, despite achievement of physiologic plasma concentrations of 24,25-dihydroxyvitamin D, we could demonstrate no metabolic or histologic benefit of therapy. Substantial osteomalacia persisted in all posttreatment biopsy specimens, appearing more severe in some cases and less severe in others. At the doses prescribed, the results of treatment of dialysis osteomalacia with 24R,25-dihydroxycholecalciferol were clinically unsatisfactory.
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PMID:Persistence of dialysis osteomalacia despite treatment with 24R,25-dihydroxycholecalciferol. 278 66

A 14-year-old Turkish boy had severe rickets that had been clinically evident since he was 2 years of age. When he was 5 years of age, he had normal serum calcium and phosphorus levels and increased alkaline phosphatase activity. Treatment with modest dosages of vitamin D (5000 U/d for 3 weeks) resulted in hypercalcemia. At 10 years of age, high-dose vitamin D (40,000 U/d) plus phosphorus (1.1 g/d) therapy for 20 days resulted in symptomatic nephrolithiasis. When, 14 years of age, he had normocalcemia, hypophosphatemia, increased alkaline phosphatase activity, and normal circulating parathyroid hormone concentration. Levels of 25-hydroxyvitamin D were normal but those of 1,25-dihydroxyvitamin D were markedly increased. Rickets and osteopenia were evident on radiographs, and osteomalacia was present on trabecular bone obtained at biopsy. Balance study results showed increased intestinal absorption of calcium and phosphorus, hypercalciuria, and increased urinary phosphorus excretion. This patient manifests an unusual form of hypophosphatemic rickets in which hypercalciuria is a cardinal feature. In contrast with most varieties of hypophosphatemia, this disorder is characterized by appropriately increased production of 1,25-dihydroxyvitamin D in response to hypophosphatemia. It is recommended that urinary calcium excretion be assessed in all patients with hypophosphatemic rickets so that appropriate therapy will be instituted.
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PMID:Hypercalciuric hypophosphatemic rickets, mineral balance, bone histomorphometry, and therapeutic implications of hypercalciuria. 278 97

Severe aluminium-induced osteomalacia is refractory to treatment with 1,25(OH)2D3 which frequently causes hypercalcemia. To further explore the mechanisms involved, we have utilized a model of short-term aluminium intoxication in the rat (total: 11 mg elemental aluminium in 3 weeks) to study (a) 1,25(OH)2D3 receptor status in a variety of classical and non-classical target organs for 1,25(OH)2D3; (b) circulating 1,25(OH)2D3 levels; (c) baseline duodenal calcium transport, utilising the Ussing chamber, to investigate the functional significance of receptor status in a classical target organ; and (d) duodenal calcium transport response to exogenously administered 1,25(OH)2D3. Both in the three week model and in the 16 week model (total: 41 mg elemental calcium) increased maximal specific binding capacity for 1,25(OH)2D3 (Nmax), that is, number of unoccupied receptors, was observed in nuclear fractions of all tissues studied. Receptor affinity, the apparent dissociation constant KD, was unchanged. Total binding capacity, measured after displacement of endogenous ligand by Mersalyl, that is, the sum of occupied plus non-occupied receptors, was also increased. Both circulating 1,25(OH)2D3, mucosa-to-serosa calcium flux (Jms) and net calcium flux (Jnet) were reduced under baseline conditions, suggesting the lack of a direct relationship between receptor expression and endorgan response. Following exogenous 1,25(OH)2D3 administration, calcium Jms and Jnet were significantly lower in the aluminium intoxicated animals, with the increment induced in Jnet in aluminium intoxicated animals being 63% of that induced in controls. Our data suggest that resistance to the action of 1,25(OH)2D3 in aluminium intoxication is postreceptor in nature.
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PMID:1,25(OH)2D3 receptors and endorgan response in experimental aluminium intoxication. 282 18


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