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)

We have examined the effects of the diphosphonate, clodronate, in 9 haemodialysis patients with severe hyperparathyroid bone disease. Clodronate (300-600 mg infused after dialysis on 5 consecutive occasions) significantly decreased mean serum calcium, phosphate and hydroxyproline. This was associated with an increase in serum immunoassayable parathyroid hormone and activity of alkaline phosphatase. These changes reversed 2-4 weeks after stopping treatment but were sustained when treatment with oral clodronate (1.6 g daily) was supplemented for 2 weeks. Our findings suggest that intravenous clodronate is capable of inhibiting osteoclast-mediated bone resorption in chronic renal failure. The therapeutic potential of clodronate alone or with vitamin D derivatives merits further evaluation, particularly in patients with severe hyperparathyroidism, when the use of D metabolites alone is precluded by the presence of hypercalcaemia.
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PMID:Effects of clodronate in severe hyperparathyroid bone disease in chronic renal failure. 214 21

Dichloromethylene bisphosphonate (C12MBP), a powerful inhibitor of bone resorption, was administered to 27 patients with primary hyperparathyroidism. It was given by either intravenous infusion (six patients, 500-100 mg day), or by intramuscular injection (six patients, 100-200 mg/day) or by mouth (15 patients, 1600-2400 mg/day) for 20-180 days. Sustained suppression of bone resorption was observed in all patients, as judged by a fall in the urinary hydroxyproline excretion. In contrast, the hypocalcaemic effect was inconsistent and short-lived, particularly in the patients without overt bone disease. The fall in serum calcium seemed largely to be due to a transient dissociation between bone resorption and bone formation and was associated with increases in circulating parathyroid hormone (PTH). In ten patients given the bisphosphonate orally for 6 months, serum calcium was unchanged but serum PTH was significantly raised. These results suggest that C12MBP may be of use for short-term correction of severe hypercalcaemia due to hyperparathyroidism, particularly in the patients with overt bone disease. However, its long-term use should not be recommended because of increased PTH secretion.
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PMID:Regulation of calcium-parathyroid hormone feedback in primary hyperparathyroidism: effects of bisphosphonate treatment. 214 99

The classic bone disease of primary hyperparathyroidism, osteitis fibrosa cystica, was characterized by subperiosteal bone resorption, osteopenia, and "brown tumors." Since the description of this skeletal disorder, the clinical profile of primary hyperparathyroidism has evolved markedly. The disease today is often characterized by no more than asymptomatic hypercalcemia, and severe bone disease is a distinct rarity. However, as we have endeavored to show in this article, newer and more sensitive techniques show significant evidence of the effect of excess parathyroid hormone on the skeleton. Bone density as measured by photon absorptiometry and bone histomorphometry show a deficit of cortical bone and a preservation or increase in cancellous bone elements in mild primary hyperparathyroidism with no clinical evidence of skeletal disease. Important questions exist as to the therapeutic implications of these data. Does the presence of parathyroid hormone effect on sophisticated testing portend the development of clinical bone disease? Should these data be used as a rationale for surgical intervention in patients who might otherwise be followed conservatively with mild primary hyperparathyroidism? The answers to these questions must await further data collection and study.
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PMID:Bone disease in primary hyperparathyroidism. 219 67

The appropriate use of phosphate binders, calcium supplements and especially calcitriol therapy has significantly decreased the incidence of overt secondary hyperparathyroidism in dialysis patients. Nevertheless some patients may still need parathyroidectomy, especially in the event of severe clinical signs and symptoms such as persistent hypercalcemia, pruritus, calcifilaxis, or extensive extra-skeletal calcification. Since aluminum-induced bone disease may resemble hyperparathyroidism in dialysis patients, whenever parathyroidectomy is contemplated the diagnosis of secondary hyperparathyroidism must be firmly established. Thus, a bone biopsy is mandatory prior to parathyroidectomy. It is our experience that once the patient goes to surgery the most important factor in the surgical approach is the presence of a skilled surgeon who has extensive experience in parathyroid gland surgery. The data comparing subtotal parathyroidectomy with total parathyroidectomy and autotransplantation are similar. The most important shortcoming is the lack of long-term follow-up. Recently, new data by several investigators has been advanced reintroducing total parathyroidectomy. Long-term observations in patients who despite total parathyroidectomy still have normal PTH levels are of special interest. In addition, long-term follow-up of these patients has shown that normal plasma calcium and phosphorus levels may be maintained without the use of Vitamin D; this occurred in the presence of active mineralization. However, our major objection to this procedure is the risk of aluminum-induced bone disease. At the present time we feel that the relative high incidence of recurrent hyperparathyroidism following subtotal parathyroidectomy is a reasonable trade off for the risk of aluminum bone disease which may develop in absence of PTH.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Parathyroidectomy in chronic renal failure: indications, surgical approach and the use of calcitriol. 221 49

To evaluate the effects of primary hyperparathyroidism (PHPT) on bone mass and structure, we have studied the iliac crest biopsies of 27 patients, 10 males (28-68 yr old) and 17 females (26-72 yr old) with mild PHPT after in vivo tetracycline labeling. All patients had mild hypercalcemia in the absence of any other cause and elevated levels of PTH without radiological evidence of bone disease. Static parameters of bone turnover (osteoid surface, osteoid volume, and eroded surface) were elevated in both men and women compared to normal values; the midmolecule RIA for PTH (PTHMM) was positively correlated with osteoid surface (r = 0.44; P less than 0.025) and eroded surface (r = 0.58; P less than 0.005). Dynamic parameters of bone turnover (mineralizing surface, expressed as double plus half single labeled surface, and bone formation rate at tissue level) were elevated compared to normal values; PTHMM was positively correlated with double plus half single labeled surfaces (r = 0.33; P less than 0.05) and with bone formation rate at the tissue level (r = 0.37; P less than 0.05). The mineral apposition rate was within the limits of normal values and positively correlated with PTHMM (r = 0.34; P less than 0.05). Histomorphometric parameters of bone structure [cancellous bone volume (BV/TV), trabecular thickness (Tb. Th), trabecular number (Tb.N), trabecular separation (Tb.Sp), cortical thickness (Ct.Th), and total bone density (TBD)] were compared to those in 20 autopsy control subjects, 12 men (33-60 yr old) and 8 women (27-75 yr old). BV/TV and Tb.N were significantly higher in PHPT patients than controls (P less than 0.02 and P less than 0.001, respectively). Tb.Sp was significantly lower in PHPT patients than controls (P less than 0.001), whereas Tb.Th was not significantly different between PHPT patients and controls. Ct.Th was significantly lower in PHPT patients than in controls (P less than 0.001), whereas TBD was not significantly different between the two groups. BV/TV was negatively correlated with age in both controls and PHPT patients. Tb.N showed a negative correlation and Tb.Sp a positive correlation with age in controls (r = -0.47; P less than 0.05 and r = 0.52; P less than 0.02, respectively), but they were not significantly dependent on age in PHPT patients. Tb.Th, while showing no significant age-related change in controls, was negatively correlated with age in PHPT patients (r = -0.42; P less than 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The histomorphometry of bone in primary hyperparathyroidism: preservation of cancellous bone structure. 231 48

From July, 1982 to April, 1989, a total of 145 patients with persistent or recurrent primary hyperparathyroidism (HPT) were explored; 105 patients had an adenoma as the cause of HPT, and in 9 patients (9%), the abnormal gland was located at or superior to the carotid bifurcation (undescended parathyroid gland). These 9 patients had 14 prior explorations for HPT including 4 median sternotomies and 5 thyroidectomies. Each of the 9 patients was symptomatic of HPT, including bone disease in 8 of 9 patients and renal stones in 4 of 9 patients. Seven patients had an undescended parathyroid adenoma correctly localized preoperatively by ultrasound (n = 5), angiography (n = 5), venous sampling (n = 1), or computed tomography scan (n = 4). These 7 patients with accurate preoperative localization were explored by an incision anterior to the sternocleidomastoid muscle high in the neck that avoided the previous operative field and allowed rapid resection of the parathyroid adenoma. In the 2 patients who did not have accurate preoperative localization, the undescended adenoma was found after long tedious exploration including median sternotomy in 1 patient. Each patient (n = 9) who had an undescended parathyroid adenoma removed was cured of hypercalcemia, and 5 patients required postoperative 1,25-dihydroxy vitamin D3 for hypocalcemia. We conclude that undescended parathyroid adenomas comprise a significant proportion (9%) of adenomas during reoperations for persistent HPT.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Undescended parathyroid adenoma: an important etiology for failed operations for primary hyperparathyroidism. 236 36

Surgical and histopathologic findings and results of subtotal resection and total parathyroidectomy with autotransplantation were evaluated in 82 hypercalcemic patients with uremic hyperparathyroidism. The mean preoperative serum calcium concentration was 2.89 mM, and the highest values were associated with more rapidly progressing hypercalcemia. Despite greatly increased total weight of the parathyroid tissue (mean 1,509 mg), 34 patients had one to five normal-sized parathyroid glands. The incidence of such glands decreased with total gland weight. Nodular hyperplasia was found in 74% of the patients, and was characterized by considerable intraindividual size difference, while diffuse hyperplasia was associated with more moderate and symmetric glandular enlargement. During follow-up averaging 4.5 years, the incidence of persistent or recurrent hypercalcemia was slightly higher after subtotal than after total parathyroidectomy (11 and 11%, vs. 9 and 7%). Biochemical and/or radiologic signs of parathyroid bone disease were present in 36 (44%) of the patients before neck exploration and normalized postoperatively in all but seven. The outcome of parathyroid surgery thus was favorable in uremic patients with hypercalcemic hyperparathyroidism.
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PMID:Surgical findings and results of subtotal and total parathyroidectomy in hypercalcemic patients with uremic hyperparathyroidism. 261 12

The pathogenesis, clinical features, indications for therapy, and current pharamacologic management of Paget's disease are reviewed. Paget's disease is a bone disorder of unknown etiology primarily affecting the elderly. Overactive bone resorption leads to the accelerated formation of disorganized, weak bone. Pain and fractures are common clinical features. Neurologic, cardiovascular, metabolic, and neoplastic complications are also reported. Because most patients are asymptomatic, the disease is often detected during routine roentgenography or laboratory tests. Primary indications for pharmacologic intervention include bone pain, neural compression, immobilization hypercalcemia or hypercalciuria, cardiac failure, and orthopedic surgery. Recurrent or non-healing fractures and rapidly progressing complications are additional indications. Drugs used in the management of Paget's disease include calcitonin, etidronate disodium, and plicamycin. Although these agents are efficacious, each has disadvantages. Clinical resistance to animal calcitonins may develop, and the cost of therapy may be prohibitive. Etidronate may induce ostemalacia. The use of plicamycin is limited by potentially severe toxicities. Dichloromethylene and aminohydroxypropylidene are promising diphosphonate compounds but are still investigational In those patients who are unresponsive to single-agent regimens, combination therapy may prove effective. Although many patients with Paget's disease do not require pharmacologic therapy, calcitonin and etidronate are the agents of choice when it is indicated.
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PMID:Pharmacologic management of Paget's disease. 266 12

We studied the effects of acute modifications in plasma calcium on parathormone (PTH) secretion in 23 patients with primary hyperparathyroidism (PHPT). In 12 patients, PTH hypersecretion was autonomous, and basal plasma calcium concentration was positively correlated with maximal serum PTH(1-84) reached during Na2EDTA infusions. In 11 patients, PTH hypersecretion remained suppressible, but with elevated set point value, and basal plasma calcium concentration was positively correlated with set point. Thus, the degree of hypercalcemia seems mainly determined by the magnitude of maximal PTH secretion and set point error in autonomous and suppressible PHPT, respectively. We have previously suggested that high serum calcitriol levels might chronically inhibit PTH hypersecretion in PHPT. We showed that hyperparathyroid patients with renal stone presentation exhibited an abnormally high value of circulating calcitriol and a moderately elevated PTH activity, while patients with severe bone disease presentation displayed a low to normal calcitriol value and a dramatically increased PTH activity. The hypothesis was supported by a recent study from our Unit in one hyperparathyroid patient with severe bone disease and normal serum calcitriol level. Increment of serum calcitriol after daily intravenous Rocaltrol for 5 days directly suppressed PTH hypersecretion without change in plasma ionized calcium.
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PMID:Determinants of parathormone secretion in primary hyperparathyroidism. 269 19

A 59-year-old man, who presented to hospital with a large expansile bone tumour over the left elbow and a mass in the right side of the neck, was eventually found to have parathyroid adenoma manifesting clinically as severe hypercalcaemia. Histological examination of a section of the neck mass showed parathyroid adenoma and the bone biopsy specimen revealed a 'brown tumour', consistent with hyperparathyroid bone disease.
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PMID:Hyperparathyroidism presenting as a large bone tumour. A case report. 271 Dec 75


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