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)

The purpose of this study is to evaluate the place of intravenous 1 alpha-hydroxyvitamin D3 (1 alpha-OH-D3) in the prevention of radiologically obvious hyperparathyroidism (HPT) in patients on maintenance dialysis while excluding aluminium phosphate binder and using a dialysate calcium concentration of 1.62 mmol which keeps the intradialytic calcium balance neutral. Therefore, 47 patients without subperiosteal resorption and previously treated by oral CaCO3 and if necessary Mg(OH)2 as phosphate binder while their dialysate calcium had a Ca level of 1.62 and a Mg level of 0.2 mmol/l were randomized into a control group of 24 who were maintained on the same treatment and an experimental group of 23. This group discontinued CaCO3 and received intravenous 1 alpha-OH-D3 after each dialysis at increasing doses up to 4 micrograms and increased Mg(OH)2 as their sole phosphate binder. When plasma Ca increased above 2.7 mmol/l, the dose of 1 alpha-OH-D3 was decreased. When plasma PO4 increased above 2 mmol/l, the dose of Mg(OH)2 was increased to the highest dose not inducing diarrhea, hypermagnesemia (less than 2 mmol/l) or hyperkalemia (less than 6 mmol/l). In case of persistent hyperphosphatemia, the dose of 1 alpha-OH-D3 was decreased. Since mean plasma alkaline phosphatase was normal, HPT was monitored on the plasma concentration of 1-84 PTH for which a previous histological study showed that frank osteitis fibrosa was present only when they were above 70 pg/ml, i.e. (about twice the upper limit of the normal value). Before the study, plasma PTH was below this limit in 16 patients of the CaCO3 group and in 14 patients of the 1 alpha-OH-D3 group. After 6 months, they remained below this limit in all patients except 2 of each group. Plasma PTH was initially above 70 pg/ml in 8 of the CaCO3 and did not change significantly throughout the study, 2 patients having at 6 months a PTH level below 70 pg/ml. In contrast with intravenous 1 alpha-OH-D3, all the 9 patients with initial frank HPT decreased their PTH levels after 2 months, the levels being below 70 pg/ml in 6 cases. However, because of hypercalcemia and/or of hyperphosphatemia in spite of a highest tolerable dose of Mg(OH)2, 1 alpha-OH-D3 doses had to be decreased down to 0.4 microgram per dialysis at the 6th month so that at 6 months 6 of 9 patients had their PTH levels above 70 pg/ml, a number comparable to that of patients treated with CaCO3 (6 of 8).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Prevention of hyperparathyroidism in patients on maintenance dialysis by intravenous 1-alpha-hydroxyvitamin D3 in association with Mg(OH)2 as sole phosphate binder. A randomized comparative study with the association CaCO3 +/- Mg(OH)2. 155 99

Control of phosphorus accumulation in chronic renal insufficiency is crucial to the prevention of secondary hyperparathyroidism and metastatic calcification. In early renal failure, calcitriol levels are normal and parathyroid hormone levels are elevated. The phosphorus levels are maintained in the normal range by the phosphaturia induced by hyperparathyroidism. In this situation, dietary phosphorus restriction increases calcitriol levels and suppresses parathyroid hormone secretion. As renal failure progresses into late stages, hyperphosphatemia is evident along with low levels of calcitriol and worsening hyperparathyroidism. Phosphorus restriction will not affect calcitriol concentrations, yet parathyroid levels may decline. During long-term dialysis, urinary excretion of phosphorus is usually minimal. Therefore, phosphorus balance is determined primarily by the net amount absorbed by the bowel and the quantity removed during dialytic therapy. Given an adequate diet, no form of conventional dialysis is able to fully compensate for the gastrointestinal absorption of phosphorus. Hence, compounds that bind phosphorus in the bowel are often necessary. With the realization that the use of phosphorus binders containing aluminum leads to aluminum accumulation and its sequelae: osteomalacia, dementia, myopathy, and anemia, other phosphorus binders have been evaluated. Calcium carbonate has been investigated the most thoroughly and is in wide use. It is inexpensive and contains a high percent of elemental calcium. However, it is only modestly potent in the binding of phosphorus, and large doses are often necessary to attain satisfactory control of phosphorus. This may lead to hypercalcemia. One approach to this problem is to decrease the concentration of calcium in the dialysate. Alternatively, a more effective phosphorus binder may be used. Calcium acetate has been shown in acute studies to have twice the binding capacity of phosphorus per calcium absorbed than calcium carbonate. Whether use of this compound decreases the incidence of hypercalcemia is unproven. Calcium citrate increases the gastrointestinal absorption of aluminum and offers no advantage over calcium carbonate. Other compounds, such as calcium ketoacids and calcium alginate, have not been extensively studied and are not generally available. The use of phosphorus binders containing magnesium in conjunction with a dialysate low in magnesium may be efficacious. Large doses of magnesium will cause diarrhea and thus limit its use as a single agent. Reasons for failure to control hyperphosphatemia include poor compliance, improper prescription of binders, poor dissolution rates seen with some generic brands of calcium carbonate, and the presence of severe hyperparathyroidism. Optimal control of serum phosphorus in dialysis patients should always be viewed in the context of adequate nutrition and protein intake.
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PMID:Hyperphosphatemia: its consequences and treatment in patients with chronic renal disease. 156 18

Alterations in renal calcitriol synthesis are important in the pathogenesis of secondary hyperparathyroidism in patients with progressive renal failure. Many of the manifestations of secondary hyperparathyroidism can be reversed by treatment with 1 alpha-hydroxylated vitamin D sterols, such as calcitriol and 1 alpha-hydroxyvitamin D3, but some studies suggest that such treatment accelerates the rate of progression of renal disease in patients with mild to moderate renal failure. Thus, calcitriol and 1 alpha-hydroxyvitamin D3 have been used infrequently in this group of patients. A review of more than 20 clinical reports indicates that the use of calcitriol or 1 alpha-hydroxyvitamin D3, in daily doses of 0.25-0.5 microgram, is rarely associated with hypercalcemia, hyperphosphatemia, or impairment in renal function. If such complications arise, they are usually reversible when treatment with vitamin D sterols is withdrawn and serum calcium levels return to pretreatment values. There is evidence that calcitriol impairs creatinine secretion by the renal tubule; thus, serum creatinine levels may increase and measurements of creatinine clearance may fall during calcitriol therapy in patients with mild to moderate renal failure without any change in true glomerular filtration rate. Daily oral doses of 0.25-0.50 microgram of calcitriol or 1 alpha-hydroxyvitamin D3 are well tolerated, and they can reverse the biochemical and histologic features of secondary hyperparathyroidism. Calcitriol therapy may be particularly valuable in patients recognized to be at higher risk of developing progressive secondary hyperparathyroidism as their renal failure slowly advances.
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PMID:The use of 1,25-dihydroxyvitamin D3 in early renal failure. 158 May 87

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

A patient with hypophosphatemic vitamin D-resistant rickets developed secondary erythrocytosis during treatment with large doses of vitamin D2 and phosphate. Erythrocytosis was accompanied by a fall in circulating plasma volume and appeared to have developed as a consequence of nephrocalcinosis because it occurred after the appearance of nephrocalcinosis following several episodes of hypercalcemia and hyperphosphatemia. Nephrocalcinosis and erythrocytosis did not disappear even after recovery of renal function. Thus, the present observations point to the importance of preventing these irreversible complications that could cause renal failure, erythrocytosis, and thrombotic events during the management of hypophosphatemic vitamin D-resistant rickets.
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PMID:Erythrocytosis in hypophosphatemic rickets: irreversible complication due to nephrocalcinosis after vitamin D and phosphate therapy. 166 79

For assessing the risk of adverse complications of surgery the group of 130 patients with post-operational hypoparathyroidism was analysed. Surgical hypoparathyroidism has been diagnosed in 51% of operated on thyroid gland patients. Laryngeal nerves have been damaged in 46.6% of patients. The injury to laryngeal nerves has been irreversible in 2/3 of patients, and reversible in the remaining 1/3. Cataract, nephrolithiasis and vitamin D3 intoxication have been observed in some cases before surgery. Their incidence increased in severe surgical hypoparathyroidism. Osteoporosis of the spine has been diagnosed in 49% of patients including some with vertebral fractures. No correlation between the degree of spine osteoporosis and diagnosis before surgery, number of operations on thyroid gland, and type of therapy has been noted. The symptoms of hypercalcemia have been diagnosed in 5 patients out of which hypercalcemia has been transient in 2 patients, and lasted for 1-5 months in the remaining 3 patients. The results of 7,873 analyses of mineral metabolism have been assessed. Hypocalcemia has been found in 38.4%, hypercalcemia in 1.6%, hypomagnesemia in 25.7%, hyperphosphatemia in 41.5%, decreased alkaline phosphatase serum activity in 28.7%, and hypercalciuria in 22.4% of cases. Surgical hypoparathyroidism is frequently accompanied by surgical hypothyroidism and injury to the recurrent laryngeal nerves.
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PMID:[Postoperative hypoparathyroidism: risk of complications]. 166 68

Since Mai et al. found, with the intestinal lavage technique, that the same dose of elemental calcium given as acetate (Ca Ac) complexed in the gut of uremic patients twice as much phosphate as calcium carbonate (CaCO3) while inducing a rather low calcium absorption, we wanted to see if half the dose of elemental calcium given as Ca Ac could control, on medium term, the predialysis plasma phosphate as well as CaCO3 while inducing less frequent hypercalcemia. This was evaluated in a cross-over study of 3 periods of 10 weeks according to the sequence Ca Ac, CaCO3 and Ca Ac, in 12 compliant patients on chronic dialysis previously treated by CaCO3. Because of poor tolerance of Ca Ac during the first period, 4 patients were excluded and the results were assessed only on the 8 patients who completed the study. For half the doses of elemental calcium (620 +/- 250 mg versus 1,310 +/- 560 mg versus 710 +/- 200 mg/day), Ca Ac allowed the same control of predialytic hyperphosphatemia (1.67 +/- 0.34; 1.74 +/- 0.32; 1.75 +/- 0.38) with paradoxically comparable normal mean plasma calcium concentration (2.61 +/- 0.14; 2.56 +/- 0.13; 2.55 +/- 0.14 mmol/l). Plasma alkaline phosphatases and intact PTH concentrations remained also stable during the 3 periods. The frequency of hypercalcemia greater than 2.75 mmol/l (12; 9; 20%) and of hyperphosphatemia greater than 2 mmol/l (17; 22; 27%) were comparable with the 2 treatments. In conclusion, Ca Ac controls predialytic hyperphosphatemia as efficiently as CaCO3 for half the dose of elemental calcium without, however, decreasing the frequency of hypercalcemia.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Control of predialytic hyperphosphatemia by oral calcium acetate and calcium carbonate. Comparable efficacy for half the dose of elemental calcium given as acetate without lower incidence of hypercalcemia. 173 15

The present study was conducted to determine whether half the dose of elemental calcium given as acetate (Ca Ac) could control on medium term the predialysis plasma phosphate as well as calcium carbonate (CaCO3) while inducing less frequent hypercalcemia. This was evaluated in a cross-over study of 3 periods of 10 weeks according to the sequence Ca Ac, CaCO3, Ca Ac, in 12 compliant patients on chronic dialysis previously treated by Ca CO3. Because of poor tolerance of Ca Ac during the first period 4 patients were excluded and the results have been assessed only on the 8 patients who completed the study. For half the doses of elemental calcium (620 +/- 250 mg versus 1310 +/- 560 mg versus 710 +/- 200 mg/day) Ca acetate allowed the same control of predialytic hyperphosphatemia (1.67 +/- .34; 1.74 +/- .32; 1.75 +/- .38) with paradoxically comparable normal mean plasma calcium concentration (2.61 +/- .14; 2.56 +/- .13; 2.55 +/- .14 mmol/l). Plasma alkaline phosphatases and intact PTH concentrations remained also stable during the 3 periods. The frequency of hypercalcemia greater than 2.75 mmol/l (12; 9; 20%) and of hyperphosphatemia greater than 2 mmol/l (17; 22; 27%) were comparable with the 2 treatments. We conclude that calcium acetate controls predialytic hyperphosphatemia as efficiently as CaCO3 for half the dose of elemental calcium without however decreasing the frequency of hypercalcemia.
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PMID:[Comparison of calcium acetate and calcium carbonate for the control of predialysis hyperphosphatemia]. 174 37

We evaluated the incidence of hypo- versus hypercalcemia and hypo- versus hyperphosphatemia in a survey of 158 patients with malignancy; 55/158 had bone metastases. When serum calcium levels were corrected for albuminemia, the incidence of hypo- and hypercalcemia was respectively 10.8% and 10.1%. Hypophosphatemia was found in 29.7% patients, hyperphosphatemia in 2.5%. The incidence was slightly different in presence of bone metastases. Hypocalcemia and hypophosphatemia prevailed in osteoblastic metastases and hypercalcemia in osteolytic metastases. The incidence of hypocalcemia and hypophosphatemia in malignancy was therefore surprisingly high, even apart from the presence of bone metastases. Both hypo- and hypercalcemia were associated with elevated serum alkaline phosphatase levels. Moreover, a calcium-phosphorus product reduction was observed in osteoblastic metastases, suggesting a condition of secondary hyperparathyroidism.
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PMID:A hospital survey of hypocalcemia and hypophosphatemia in malignancy. 174 50

Patients on CAPD using calcium carbonate (CaCO3) as phosphate binder might benefit from low-calcium (Ca) concentration dialysis solutions; however, no data are available for the effects of this regimen on Ca metabolism. We studied 10 patients on stable CAPD regimens with standard dialysis solutions (Ca 7 mg/dL) who were taking CaCO3 to control hyperphosphatemia (mean daily doses 4.5 +/- 2.4 g). Hypercalcemic episodes had been recorded in 6 patients. Standard dialysis solutions were replaced with solutions containing 5 mg/dL of Ca. Calcium and phosphate peritoneal mass transfer (MT), serum concentrations of total Ca, ionized Ca (Ca++), phosphate, intact PTH, and mid-molecular PTH, were evaluated before and 48 hours after change of dialysate. The switch to low-Ca solutions was accompanied by significant changes in calcium mass transfer (Ca MT) (+9.84 +/- 48.22 versus -96.74 +/- 48.32 mg/day, p less than .001). Ca MT was significantly (p less than .05) correlated with the serum/dialysate Ca gradient. There was no difference in phosphate MT. Serum Ca++ significantly (p less than .05) decreased from 5.20 +/- 0.32 to 4.88 +/- 0.36 mg/dL, and intact PTH significantly increased (81.5 +/- 139 versus 112.4 +/- 168 pg/mL, p less than .05). It is concluded that dialysis solutions with Ca 5 mg/dL result in a negative peritoneal Ca MT and can be useful to prevent and treat hypercalcemia in CAPD patients taking CaCO3 as phosphate binder. A careful monitoring of ionized calcium, PTH, and phosphate is suggested when an extensive and long-term use of this solution is considered.
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PMID:Short-term effects of low-calcium dialysis solutions on calcium mass transfer, ionized calcium, and parathyroid hormone in CAPD patients. 175 98


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