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)

Fogelman's score (FS) was used to determine the usefulness of 99mTc pyrophosphate (Tc-PP) bone scintigraphy in the evaluation of dialysis osteodystrophy. FS correlated well with bone 47Ca accretion rate. It remained stable after six months in patients treated with 1 alpha (OH)D3 and increased significantly in a randomised group of untreated patients. It decreased after two years of 1 alpha (OH)D3 therapy while serum calcium increased and iPTH and alkaline phosphatases decreased. Patients with low FS, treated by 1 alpha (OH)D3, rapidly developed hypercalcaemia. In cases of spontaneous hypercalcaemia, parathyroidectomy did not normalise serum calcium in patients with low FS despite a significant decrease in serum iPTH. Lower FS were associated with a higher increase in serum aluminium after desferrioxamine (DFO) administration and in two cases of proven aluminium osteomalacia, DFO therapy was followed by a dramatic increase in FS.
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PMID:Usefulness of 99mTc pyrophosphate bone scintigraphy in the survey of dialysis osteodystrophy. 298 2

Tumour extracts from two patients with humoral hypercalcaemia of malignancy contained material which stimulated adenylate cyclase in chick renal membranes and in rat osteosarcoma cells. Adenylate cyclase-stimulating activity in each system was inhibited by a specific parathyroid hormone (PTH) antagonist. Studies in two HPLC systems suggested that the adenylate cyclase-stimulating factors extracted from these tumours differed from each other and from synthetic human parathyroid hormone 1-34. The presence of similar PTH-like adenylate cyclase stimulating material(s) in oncogenic osteomalacia suggests that adenylate cyclase stimulating factor(s) may not be the direct or the sole cause of hypercalcaemia.
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PMID:Humoral hypercalcaemia of malignancy: report of two further patients with biochemical studies on tumour extracts. 301 3

Renal failure is frequently associated with osteodystrophia due to secondary hyperparathyreoidism and/or increased aluminum intake. The problem of hypercalcemia and hyperphosphatemia can more easily controlled by CAPD than by hemodialysis. Total serum and ionized calcium levels are rapidly normalized by a CAPD regime of four 2-1 exchanges with 1.75 mmol/l Ca. Under the same CAPD regime 250-300 mg phosphate are removed per day. Depending on the ingestion of phosphate, 100-200 mg phosphate per day remain to be removed by phosphate binding agents. Since the main source of aluminum in CAPD patients is oral ingestion of aluminum-containing phosphate binders, serum levels should be regulated by diet and calcium carbonate. To suppress PTH secretion serum ionized calcium levels need to be maintained at the upper limit of normal. This can also be achieved by the use of oral calcium carbonate. Vitamin D or analogs should be prescribed only when clinically indicated by persistent hypocalcemia, osteitis fibrosa or non-aluminum related osteomalacia.
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PMID:Renal osteodystrophy and aluminum bone disease in CAPD patients. 305 62

A 7-year study of a patient with tumor (hemangiopericytoma)-induced hypophosphatemic osteomalacia (TIO) is presented, and the findings are in keeping with the depressed tubular reabsorption of phosphate and low 1,25(OH)2 vitamin D levels seen in other studies. Despite normalization of 1,25(OH)2 vitamin D levels with pharmacologic doses of vitamin D2, there was no discernible effect on serum phosphorus levels. Also, despite hypercalcemia induced by pharmacologic doses of vitamin D2, serum parathyroid hormone levels were persistently elevated, and gradually returned to subnormal levels after removal of the tumor. Following removal of the tumor, there was a rapid increase of the 1,25(OH)2 vitamin D levels to supraphysiologic levels, prompt appropriate increase in tubular reabsorption of phosphate levels, and symptomatic improvement in the osteomalacia. Speculations on the physiologic and pathophysiologic role of the putative hormone(s) produced by the tumors associated with this syndrome are presented.
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PMID:Studies in a patient with tumor-induced hypophosphatemic osteomalacia. 308 59

Extremely low birth weight infants are particularly prone to rickets (osteopenia) due to their rapid growth and to deficient intake of calcium and phosphate. In some premature infants suffering from phosphate depletion hypercalcemia syndrome may precede bone demineralisation. Additionally, the adverse effects of calciprivic drugs (phenytoin, phenobarbital, glucocorticoids, furosemide, heparin) contributing to the development of neonatal rickets are discussed. Phosphorus depleted or heparin treated experimental animals develop impairment of mineralisation as manifested by rickets or osteomalacia. Some clinical cases of neonatal rickets are reported and a dosage schedule for parenteral infusion of minerals is given.
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PMID:[Disorders of bone metabolism in premature infants]. 309 22

Radionuclide imaging with Tc-99m diphosphonates is not an effective method for detecting or ruling out most osteoporotic diseases including senile osteoporosis or accelerated postmenopausal osteoporosis, and the slow loss of bone tissue generally remains undetected by this modality. Nonetheless, it frequently surpasses or supplements radiographic findings in evaluating the focal complications of metabolic bone disease, including fractures, microfractures, stress fractures, vertebral compressions, Milkman-Looser zones, aseptic necrosis, and acute infarction. In contrast to its secondary role in osteoporosis, bone imaging is of prime importance in investigating hypercalcemia, because the major cause of this abnormality is skeletal metastatic malignancy. In defective bone mineralization due to hyperparathyroidism or osteomalacia, a general increase in diphosphonate skeletal uptake is detected more frequently than radiographic abnormalities. However, normal skeletal images do not rule out metabolic bone disease. Biochemical testing is more reliable in detecting primary hyperparathyroidism. On the other hand, in renal osteodystrophy, biochemical abnormalities are variable and bone imaging is helpful in assessing the severity of skeletal involvement, but not its etiology. Many methods of quantitating the kinetics of Tc-99m diphosphonates have been explored, such as plasma clearance, bone-to-soft-tissue ratios, 24-hour total body retention and 24-hour urinary excretion. None of these have been widely accepted. The value of bone imaging is established in other systemic diseases, most notably in Paget's disease, hypertrophic pulmonary osteoarthropathy, sickle cell disease, fibrous dysplasia, and sympathetic dystrophy.
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PMID:Radionuclide imaging in metabolic and systemic skeletal diseases. 331 47

We report on a 5-year, prospective, double-blind trial of 1,25 dihydroxycholecalciferol (calcitriol) versus placebo in 76 hemodialysis patients without biochemical or radiological evidence of bone disease. Calcitriol, 1 microgram daily, regularly induced hypercalcemia. Doses of 0.25 microgram daily or less proved satisfactory in most patients. During calcitriol treatment, plasma calcium concentration was significantly higher and serum parathyroid hormone concentration significantly lower than on placebo. There was no difference in the rates of development or of progression of vascular calcification in the two groups. Significantly more patients on placebo (17 vs. 6, p less than 0.05) developed a sustained elevation of plasma alkaline phosphatase concentration. Calcitriol appeared to protect against the development of histological evidence of osteitis fibrosa but not of osteomalacia, but accumulation of aluminum in bone occurred during the study. We conclude that calcitriol delays and may prevent the development of osteitis fibrosa in patients receiving regular hemodialysis and may reasonably be prescribed routinely in hemodialysis patients without biochemical or radiological abnormality, unless there is a substantial prospect of early renal transplantation.
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PMID:Controlled trial of calcitriol in hemodialysis patients. 353 32

45 bone biopsies from patients with chronic uremia were reviewed to define which noninvasive investigations were of value in predicting the histological diagnosis and to quantify the spectrum of uremic bone disease at a center that has consistently used an aluminum-free dialysis bath. 17 biopsies were taken postmortem. 15 patients received conservative treatment, the rest were on maintenance dialysis. 13 patients had symptomatic bone disease. Virtually all patients with a uremia duration greater than 3 years had uremic osteodystrophy. All patients with clinical bone disease, hypercalcemia or raised alkaline phosphatase activity had osteodystrophy, but the specific histology was not indicated. Greatly raised parathyroid levels suggested secondary hyperparathyroidism, but the test was only 100% specific when 20 times normal. Total aluminum consumption was highly indicative of bone aluminum concentration (p less than 0.0001) and aluminum-related osteomalacia (5 cases), suggesting that a considerable proportion of uremic bone disease is iatrogenic. Serum aluminum was of some use in the diagnosis of aluminum-related osteomalacia, but was not wholly reliable. Bone mineral content (BMC) using both forearm measurements and total body bone mineral levels (TBBM) were assessed in 32 patients and were found to be reduced in 12, with a preponderance of secondary hyperparathyroidism. BMC and TBBM were negatively correlated to resorbing surfaces and bone formation rate, suggesting that secondary hyperparathyroidism is the uremic bone disease that represents the greatest threat to bone mass. It is concluded that while noninvasive investigations give considerable information, reliable diagnosis requires the use of histological methods.
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PMID:Noninvasive diagnosis of uremic osteodystrophy: uses and limitations. 363 Nov 50

In a 71-year-old patient with osteomalacia, masked primary hyperparathyroidism was detected by vitamin D therapy for hypercalcemia. Surgery revealed a parathyroid tumor. Interpretation of total plasma calcium may be difficult unless the 25-hydroxyvitamin D levels are outside the normal range.
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PMID:[Hyperparathyroidism masked by osteomalacia. Is vitamin D administration in every case of osteomalacia problem-free?]. 371 42

To evaluate the effects of calcitriol (1,25-dihydroxyvitamin D3) therapy for the bone disease induced by long-term treatment with anticonvulsants, we reviewed the medical records of 330 institutionalized oligophrenic children and young adults under 26 years of age to identify the 144 children who required anticonvulsant therapy. Of this latter group, 52 children were found to have serum alkaline phosphatase levels elevated more than 2 SDs above normal and were enrolled into this prospective three-year study. To achieve rapid resolution of the bone disease, we elected to use calcitriol at 0.25 to 0.75 micrograms/d. After 1195 patient-months of treatment, our data suggest that the dystrophic process was reversed in 42.3% of the cases, as judged by decreases in serum alkaline phosphatase levels at six months, 65.4% of cases at 12 months, and 83.3% of cases at 13 to 18 months. By 30 months of follow-up, all patients showed significant lowering of serum alkaline phosphatase levels. The improvements were slow and gradual. Twenty-six patients in the treatment series of 52 patients initially showed signs of rickets or osteomalacia on roentgenograms of the wrists. Of these 26 patients, 12 (46%) showed improvement on roentgenograms within 24 months of the beginning of treatment. With reference to complications, hypercalcemia (calcium level, greater than 11 mg/dL [2.74 mmol/L]) was encountered at the rate of one episode per 44 patient-months of treatment. Our results strongly suggest that calcitriol is effective in healing anticonvulsant-related osteomalacia among children and youths, with a low incidence of complications.
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PMID:Bone disease induced by anticonvulsant therapy and treatment with calcitriol (1,25-dihydroxyvitamin D3). 375 5


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