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)

Four patients under maintenance dialysis for chronic renal failure were suffering from aluminium toxicity. One showed evidence of encephalopathy, two presented with fractures and one was asymptomatic. Hypercalcaemia was constant, whereas high serum aluminium levels were present in only 2 patients. In all cases, iliac bone biopsy specimens, non-decalcified and stained with Aluminium , were found to contain aluminium deposits along the mineralization fronts, thus confirming the diagnosis of aluminium overload. In addition, biopsies revealed an excess of osteoid tissue with morphological and dynamic signs of osteomalacia (2 cases) or strongly depressed bone formation (2 cases). Histomorphometric bone biopsy appears to be the best mean of diagnosing aluminium intoxication and analyzing its effects on bone remodeling and mineralization. It is also very useful to monitor the treatment.
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PMID:[Aluminum poisoning in renal dialysis patients: bone histology. Value of quantitative bone biopsy]. 623 88

A method is described for the quantitation of total skeletal activity during bone scans. The method requires a single plasma sample only, taken at the time of imaging. The ratio of % injected dose of 51Cr EDTA to that of 99Tcm MDP is calculated from this sample following combined injection of the two radiopharmaceuticals. The 51Cr EDTA level corrects for the glomerular filtration of 99Tcm MDP. Using this method, which only requires a gamma counter, significant differences from normal controls have been shown in patients with osteomalacia, renal osteodystrophy, Paget's disease and hypercalcaemia. The method provides routine quantitative data to add to the imaging information in the bone scan.
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PMID:Chromium 51 EDTA/technetium 99m MDP plasma ratio to measure total skeletal function. 623 85

Growth arrest and renal osteodystrophy is a major problem in renal insufficiency of children. The present report describes our experiences in managing renal osteodystrophy by using vitamin D3 for 24 months. Values in plasma of Ca, Mg, alkaline phosphatase, iPTH, 25-OH-D were determined regularly. Skeletal X-rays and analysis of iliac crest bone biopsies were obtained in each child. In treatment with vitamin D3 no hypercalcemia was seen despite high serum levels of 25-OH-D. Plasma-Ca, alkaline phosphatase, and iPTH normalized nearly. Radiographic abnormalities improved. Bone biopsies showed improvement in signs of secondary hyperparathyroidism and ostitis fibrosa, whereas osteomalacia remained unchanged. Osteoblast population showed a small reduction. No real increment in body growth was seen.
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PMID:[Influence of vitamin D therapy on renal osteodystrophy in children (author's transl)]. 624 57

The objectives of this study were to evaluate the effects of vitamin D(3) (D(3)) and 1,25-dihydroxyvitamin D(3) (1,25-(OH)(2)D(3)) on uremic bone disease independent of their action on the intestine. The histomorphology of tibial metaphyses in uremic (5/6 nephrectomized [5/6 Nx]) rats fed a low-calcium-low-phosphorus (LCLP) diet was compared with sham-operated (SO) rats fed an LCLP diet and 5/6 Nx rats fed an LCLP diet and given 15,000 IU D(3) or 5 units (135 ng) 1,25-(OH)(2)D(3) daily for 7 days. A marked osteomalacia characterized by an increased percentage of active and inactive trabecular osteoid surface and thickened growth plates developed in proximal tibial metaphyses in 5/6 Nx rats given the placebo, compared with SO rats. These bone changes were associated with relative hypophosphatemia, hypophosphaturia, and hypercalciuria in 5/6 Nx rats. In 5/6 Nx rats treated with D(3) or 1,25-(OH)(2)D(3) the growth plates had undergone mineralization and vascular invasion and were markedly reduced in thickness. Other parameters of osteomalacia in trabecular bone were not different from 5/6 Nx rats given the placebo. There was a significant decrease in osteoclasts per millimeter of trabecular surface perimeter in D(3)- and 1,25-(OH)(2)D(3)-treated rats. These bone changes were associated with hypercalcemia, hyperphosphatemia, and hyperphosphaturia, compared with 5/6 Nx rats given the placebo. It was concluded that in uremic rats fed the LCLP diet, shortterm treatment with either pharmacologic levels of D(3) or 1,25-(OH)(2)D(3) corrected only lesions in the growth plate. Osteoid seams were not reduced in treated rats, although the serum calcium-phosphorus product was elevated. The 5/6 Nx rat fed the LCLP diet appears to be a useful model for the rapid induction of uremic osteomalacia in adult animals.
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PMID:Short-term effects of vitamin D3 and 1,25-dihydroxyvitamin D3 on osteomalacia in uremic rats fed a low calcium-low-phosphorus diet. 626 57

Fifteen patients with dialysis osteomalacia were treated with 24,25-dihydroxyvitamin D3 in dosages up to 10 micrograms per day for two to 24 months. All had previously had no improvement during treatment with calcitriol but had been remarkably susceptible to hypercalcemia. When 24,25-dihydroxyvitamin D3 was given with either calcitriol or dihydrotachysterol, serum calcium levels were significantly lower than during treatment with calcitriol or dihydrotachysterol alone. Eight of nine patients who received combined therapy with 24,25-dihydroxyvitamin D3 and calcitriol for longer than two months had clinical improvement; six patients underwent repeated bone biopsy and showed evidence of improved bone mineralization. Patients who received 24,25-dihydroxyvitamin D3 alone did not improve clinically. Since 24,25-dihydroxyvitamin D3 appears to improve calcium homeostasis and bone mineralization in some patients with severe dialysis osteomalacia when administered with 1-hydroxylated vitamin D metabolites, further controlled studies are warranted.
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PMID:Preliminary trials with 24,25-dihydroxyvitamin D3 in dialysis osteomalacia. 633 16

Three women on different forms of maintenance dialysis developed persistent steroid-responsive idiopathic hypercalcaemia, with low calcium absorption, severe skeletal decalcification, multiple fractures, and severe clinical problems. Bone histology showed osteomalacia with suppression of osteoblast activity and no hyperparathyroidism. The disease persists at least six months after transplantation. The features are compatible with poisoning by a toxin with many similar properties to aluminium: we only found significant aluminium overload in one of these cases.
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PMID:Idiopathic hypercalcaemia of chronic dialysis. 634 38

Although the nutritional aspects related to bone development and subsequent bone loss have been appreciated for many years, they are now being reemphasized in view of current information concerning the vitamin D endocrine system, the development of new assay procedures and more sensitive radiologic techniques to assess changes in bone mass, and the realization that clinical problems related to bone loss will increase as individuals live longer. The vitamin D endocrine system is complex, involving the skin, liver, and kidney for synthesis of the vitamin D metabolites and, primarily, the intestine and bone for biologic expression. Numerous factors and disorders affecting the skin, gastrointestinal tract, and kidney will adversely affect vitamin D metabolism. Vitamin D deficiency is common in elderly individuals, especially those who are chronically ill, house-bound, and poorly nourished. Subclinical vitamin D deficiency and osteomalacia may also be complicating problems in elderly patients with osteoporosis and hip fractures. At present the role of the vitamin D endocrine system in the pathogenesis and treatment of osteoporosis is unclear. There is little evidence that vitamin D or its metabolites are helpful in osteoporosis, except perhaps to heal osteomalacia which may be present. It is hoped that encouraging results will follow the use of more potent vitamin D metabolites, either alone or in combination with other agents. Calcium homeostasis is affected by numerous dietary factors (including protein, phosphorus, fiber, and lactose) and drugs (including alcohol, diuretics, and antacids), and calcium absorption in the intestine and the ability to adapt to low-calcium diets will decrease with advancing age. There are conflicting reports concerning the relation between low-calcium intake and osteoporosis, and about the role of calcium intake in the development and then maintenance of bone mass. There is little doubt that many older individuals ingest less calcium than is recommended, especially at a time when even more may be required to maintain bone mass. Several studies show that calcium supplementation producing a total calcium intake of 1,200-1,500 mg/day can slow the rate of bone loss. When the high doses of calcium are given along with vitamin D, periodic monitoring of blood and urine calcium is necessary to avoid hypercalcemia and hypercalciuria.
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PMID:The vitamin D endocrine system, calcium metabolism, and osteoporosis. 636 21

Forty one elderly patients admitted to hospital for acute illnesses were also found to have subclinical osteomalacia. Immediately before discharge, therefore, all were randomised to receive either vitamin D2 25 micrograms daily, alfacalcidol 0.5 micrograms daily, or placebo. Treatment was given for at least three months, those allocated to placebo then being switched to an active drug. Within the first three months of treatment with either of the active drugs most patients had exhibited a fall to normal in osteoid values. In only four treatment periods was there a mild increase in serum calcium concentration, and in no patient was this accompanied by deterioration in renal function. Any increase in serum creatinine concentration was invariably attributable to the underlying disease for which the patient had been admitted in the first place. Subclinical osteomalacia in the elderly may be corrected by relatively low doses of alfacalcidol (0.5 micrograms daily) or vitamin D2 (25 micrograms daily) given for three months. Such treatment is safe and not accompanied by a serious risk of hypercalcaemia or renal impairment.
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PMID:Safety of treatment for subclinical osteomalacia in the elderly. 643 81

A 54-year-old patient with fracturing dialysis osteomalacia and dementia demonstrated rapid deterioration following parathyroidectomy which was performed for sustained hypercalcemia. Reduction of the total body aluminum burden was attempted using desferrioxamine (DFO) as a chelating agent. After 6 months, DFO infusion resulted in sustained clinical remission of both neurological and skeletal symptoms, associated with an improvement in the EEG and improved mineralization of bone. A reduction in total body aluminum burden was reflected by reduced skeletal aluminum content, quantitated histochemically in iliac crest bone biopsies before and after DFO therapy. Dramatic increases in serum aluminum levels were documented in the initial weeks of DFO therapy leading to increased removal of aluminum during dialysis; in vitro studies indicated that the ultrafiltrable fraction of serum aluminum increased from 17 to more than 60% after initiating DFO treatment. However, after 6 months of therapy, serum aluminum levels remained unchanged after DFO infusion. These findings suggest that the serum aluminum response to DFO infusion might be a useful reflection of the total-body aluminum burden and also a reflection of the adequacy of a chelation program designed to reduce whole-body aluminum content.
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PMID:Successful treatment of dialysis osteomalacia and dementia, using desferrioxamine infusions and oral 1-alpha hydroxycholecalciferol. 651 16

Because calcitonin administration has been shown to decrease the serum calcium level in certain hypercalcemic conditions, 10 patients on maintenance dialysis with renal osteodystrophy and persistent hypercalcemia were treated with salmon calcitonin for 3 months. While plasma calcium concentrations were reduced by calcitonin therapy in four patients, therapy was ceased in two patients due to a worsening of their hypercalcemia, although in another two patients the initial worsening of the hypercalcemia settled with continued therapy. No significant changes in calcium levels occurred in the remaining two patients. Analysis of the data suggests that a hypocalcemic effect of calcitonin was most likely in the presence of osteomalacia, while predominant osteitis fibrosa favored a hypercalcemic response. Calcitonin administration caused a mean increase in parathyroid hormone (PTH) secretion 3.6 +/- 1.5 to 6.5 +/- 1.7 ng/ml; p less than 0.05) after 6 weeks of therapy. Three patients reported improvement in their bone pain. These studies show that despite possible symptomatic and morphological effects of calcitonin, its hypocalcemic effect in patients with renal osteodystrophy and hypercalcemia is inconsistent.
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PMID:Effect of calcitonin on hemodialysis patients with hypercalcemia and renal osteodystrophy. 653 90


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