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)

Renal bone disease is an important cause of morbidity in patients on dialysis. The prevalence of renal bone disease, especially aluminium related bone disease, has not been studied in the Singapore dialysis population. As such, we studied 45 haemodialysis patients for renal bone disease using biochemical and radiological parameters. Selected patients underwent a renal biopsy. There were 29 males and 16 females, mean (+/- SEM) age, 44.6 +/- 13.4 years. The duration of haemodialysis ranged from two months to ten years, mean 18.5 months. 75.4% of patients had hyperphosphatasemia, 24.4% had hypocalcemia and two patients had hypercalcemia. There was a wide range in the serum parathyroid hormone levels and 55.4% of patients had serum parathyroid hormone levels > 1000 pmol/L. Patients with symptoms and radiological abnormalities had significantly higher serum parathyroid hormone and alkaline phosphatase levels than those without (P < 0.005). The desferrioxamine infusion test was positive, with an increment in serum aluminium (DL) > 100 mg/L in five patients. Skeletal survey was positive for renal bone disease in 24.4% of patients. There was a significant correlation between the serum parathyroid hormone level, DA1 and the duration of dialysis (r = 0.752, p < 0.001 and r = 0.837, p < 0.001 respectively). There was no correlation between serum parathyroid hormone, calcium, phosphate levels and DA1. The serum haemoglobin concentration and ferritin levels did not show a correlation with DA1. Bone biopsy revealed hyperparathyroid bone disease in two patients, aluminium-related bone disease in one patient and mixed uraemic osteodystrophy in one patient.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Renal bone disease in patients on haemodialysis: biochemical and radiological assessment. 129 14

Renal osteodystrophy presents with a spectrum of histologic abnormalities. A new entity characterized by a marked decrease in bone turnover without osteoid accumulation, that is, adynamic bone disease, has recently emerged. This new form was thought to be primarily related to aluminum accumulation. Since aluminum-containing phosphate binders have been widely replaced by calcium salts, adynamic bone disease would be expected to disappear over time. However, not only is adynamic bone disease observed in the absence of aluminum intoxication, its incidence does not seem to have decreased. We conducted a retrospective study in 1,803 patients on chronic maintenance dialysis who were biopsied during the last 10 years and assessed the incidence of adynamic bone disease over time in an effort to elucidate the factors associated with its occurrence. Adynamic bone disease was first seen in 1984 in the laboratory. Its incidence increased gradually over the years and, in 1991, still affected approximately 20% of the patients. The primary factors associated with the occurrence of adynamic bone disease include: (a) aluminum accumulation which is currently found in 60% of the patients on chronic maintenance dialysis undergoing biopsies, (b) increasing age of the patients on dialysis, (c) diabetes, and, possibly, (d) chronic ambulatory peritoneal dialysis. The clinical relevance of adynamic bone disease deserves further study. At present, this entity is associated with a tendency towards hypercalcemia, aging of bone due to stunted bone remodeling, a condition which might be associated with impaired repair of physiologic microdamages, and accumulation of microfractures leading to mechanical incompetence and ultimately to higher risk of fractures.
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PMID:Risk of adynamic bone disease in dialyzed patients. 140 83

Renal osteodystrophy therapy in dialysis patients with calcitriol and intestinal phosphate binders containing calcium entails the risk of hypercalcemia. A study was performed using 35 hemodialysis patients to see whether the time of day when calcitriol is administered influences the incidence of hypercalcemia. It was shown that simply by administering at night (11:00 PM), the occurrence of hypercalcemia was significantly reduced. While greater than 80% of patients developed hypercalcemia when calcitriol was administered in the morning, when administered at night, this figure was only 50% (P less than 0.013). At the same time, the extent of hypercalcemia when calcitriol was administered at night was significantly lower than when it was administered in the morning. The incidence of hypercalcemia occurred regardless of the type of phosphate binder containing calcium used, whether it was calcium acetate or calcium carbonate. In addition, hypercalcemic episodes were always associated with hyperphosphatemia. On the basis of the above information, it would be expedient to administer calcitriol at night to dialysis patients, in order to reduce the risk of hypercalcemia and to preserve the hypophosphatemic effect of the applied intestinal phosphate binders.
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PMID:Reduced risk of hypercalcemia for hemodialysis patients by administering calcitriol at night. 158 35

Prevention of bone disease associated with impairment of the renal function is desirable. Attempts at such prevention inevitably also embrace prevention of the extraosseous consequences of autonomous hyperparathyroidism, such as the effects of hypercalcaemia, need for parathyroid surgery, and, perhaps, toxic effects of the parathyroid hormone. Strategies for prevention in early, moderate, and end-stage renal failure are reviewed and discussed with particular reference to dietary phosphorus restriction, use of gut phosphorus binders, control of acidosis, calcium supplementation, use of oral and intravenous calcitriol, and use of synthetic analogues of 1,25-dihydroxyvitamin D3. The onset of severe renal osteodystrophy can be delayed. Early attempts at prevention are logical, but we do not know whether these will reduce the need for parathyroid surgery or will make patients feel better or live longer. The costs of prophylaxis--both financial and in terms of incidence and severity of complications--remain to be defined. An individual approach to each patient with renal impairment seems at present appropriate.
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PMID:Prevention of renal osteodystrophy. 181 86

Many hemodialysis patients are still suffering from secondary hyperparathyroidism although 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) has been used to treat renal osteodystrophy for the last two decades. The main reason for its failure to correct the secondary hyperparathyroidism is that in patients, hypercalcemia occurs before adequate parathyroid hormone (PTH) suppression is obtained when a large daily dose of 1,25(OH)2D3 is started. In this study, the oral dose of 1,25(OH)2D3 (4.0 micrograms) was administered only twice a week at the end of hemodialysis ('oral 1,25(OH)2D3 pulse therapy'), in 19 patients with severe secondary hyperparathyroidism. Serum immunoreactive PTH started to decrease after 6 weeks of therapy, and the original level of 41.2 +/- 7.24 was reduced to 24.4 +/- 6.12 ng/ml by the end of the 6-month therapy (p less than 0.001). Serum alkaline phosphatase also was reduced by 64.4%. Three out of 19 patients suffered from hypercalcemia during the 4th month of therapy. Calcium supplement given to 6 other patients with severe secondary hyperparathyroidism did not lower serum PTH levels significantly after 6 weeks of therapy, although serum calcium levels increased and were sustained above 10 mg/dl for the last 5 weeks. These findings strongly suggest that the suppressive effect of the oral 1,25(OH)2D3 pulse therapy was attained by a direct action of 1,25(OH)2D3 on the parathyroid gland rather than by its ability to elevate serum calcium levels. In conclusion, the oral 1,25(OH)2D3 pulse therapy effectively lowered PTH levels in hemodialysis patients who cannot tolerate large daily doses of 1,25(OH)2D3.
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PMID:The 'oral 1,25-dihydroxyvitamin D3 pulse therapy' in hemodialysis patients with severe secondary hyperparathyroidism. 204 11

Eight children with terminal renal insufficiency on continuous ambulatory peritoneal dialysis were followed for 12 months to evaluate laboratory parameters of mineral ion and bone metabolism. Calcium carbonate (range 47-295 mg/kg body weight per day) was given in combination with low doses of either vitamin D or 1,25(OH2D3. Blood urea nitrogen and serum phosphate concentrations remained well controlled throughout the observation period. A significant increase in serum calcium levels from 2.35 +/- 0.18 to 2.61 +/- 0.22 mmol/l (mean +/- SD) was observed during the first 6 months. Alkaline phosphatase activity and mid-C-regional parathyroid hormone, both indirect parameters of bone metabolism, revealed no evidence of severe secondary hyperparathyroidism. Our data indicate that calcium carbonate may be sufficient to induce relative hypercalcaemia in uraemic children, and thus reduce the risk of developing renal osteodystrophy. Unwanted side-effects of vitamin D preparations, i.e. increased intestinal phosphate absorption and hypercalcaemia after successful renal transplantation, may thus be avoided.
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PMID:Efficacy of calcium carbonate and low-dose vitamin D/1,25(OH)2D3 in reducing the risk of developing renal osteodystrophy in children on continuous ambulatory peritoneal dialysis. 208 63

The secondary hyperparathyroidism of renal failure is an important component of renal osteodystrophy. We studied PTHmRNA levels and their regulation in control and subtotal nephrectomized (5/6 NX) rats at 3 wk, as well as levels of the 1,25(OH)2D3 receptor mRNA in parathyroids. Serum 1,25(OH)2D levels were decreased in 5/6 NX, whereas PTHmRNA levels were increased (7 +/- 0.7 OD U, N = 4) compared to controls (2.1 +/- 1.2, P less than 0.01); both decreased after 1,25(OH)2D3 (100 pmol/100 g body weight). Similar results were found in 5/6 NX rats after 3 months. There was no change in actin mRNA levels. PTHmRNA levels were highest in 5/6 NX rats with the most severe renal failure. The parathyroid gland 1,25(OH)2D3 receptor mRNA levels were not different between 5/6 NX rats and controls and were not affected by 1,25(OH)2D3 (100 pmol/100 g body weight daily) at 1 or 3 days. PTHmRNA levels of 5/6 NX rats did not increase when the serum calcium was decreased from 2.8 +/- 0.05 mmol/L to 0.9 +/- 0.15 mmol/L at 3 or 5 h, which contrasted with the marked increase in PTHmRNA in normal rats after hypocalcemia. As in normal rats, after hypercalcemia (4.8 mmol/L at 1 h) there was no change in the 5/6 NX rats' PTHmRNA levels. These results show that 5/6 NX rats have increased PTHmRNA levels that are normally regulated by injected 1,25(OH)2D3 but not by calcium. Parathyroid gland 1,25(OH)2D receptor mRNA levels are not increased in 5/6 NX in contrast to the increased PTHmRNA, which reflects the larger glands of uremia. 1,25(OH)2D receptor mRNA levels were not regulated by 1,25(OH)2D3.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Regulation of parathyroid cell gene expression in experimental uremia. 210 57

Circulating immunoreactive intact human parathyroid hormone (PTH) was measured by a direct immunoradiometric assay (IRMA) and the results compared with a radio-immunoassay (RIA) which required extraction and concentration prior to assay. The sensitivity of the IRMA was better than that of the RIA (0.6 vs 2.0 pmol/L). In control subjects the hPTH concentrations ranged between 0.6 and 6.7 pmol/L and in patients with hypercalcaemia due to malignant diseases, sarcoidosis and hypoparathyroidism none could be detected. In patients with primary hyperparathyroidism the concentrations ranged from 5.2 to 27.0 pmol/L. In patients with renal osteodystrophy serum human PTH concentrations ranged from 7.6 to 285 and in those with chronic renal failure but without evidence of renal osteodystrophy from 0.5 to 5.2 pmol/L. The major advantages of the IRMA are its much simpler performance and its higher sensitivity which makes studies of the physiology of PTH secretion in humans possible.
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PMID:Immunoradiometric assay for intact human parathyroid hormone: characteristics, clinical application and comparison with a radio-immunoassay. 231 Jan 59

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


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