Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020437 (hypercalcemia)
 10,293 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Primary hyperparathyroidism (PH) is now considered a common condition. Its frequency and the deleterious long-term effects of hypercalcemia make a correct diagnosis mandatory. We attempted to evaluate the usefulness of the indexes of parathyroid function and hormone measurements more commonly used in the diagnosis of PH. To this end we studied 64 patients, distributed in three groups: group with PH, group with hypercalciuric renal lithiasis (HRL) and control group (CG). The results were evaluated with a test of comparison of means and a stepwise discriminating regression analysis. The 8 most useful measurements to differentiate PH from HRL and CG were serum calcium, corrected serum calcium, serum phosphorus, fasting calcium excretion (FCE), maximal tubular calcium reabsorption (MTCR), maximal tubular phosphate reabsorption (MTPR), osteocalcin, PTH half molecule (PTH-HM) and 1,25-dihydroxyvitamin D. The 3-variable and 4-variable groups with a highest discriminating ability were: serum calcium, FCE and PTH-HM, and serum calcium, FCE, PTH-HM and MTPR. We think that the measurement of these four variables is the most adequate strategy for the diagnosis of PH.
 ...
PMID:[Biochemical profile of primary hyperparathyroidism. Comparative study with hypercalciuric renal lithiasis]. 274 10

We have measured classic markers of bone turnover, serum alkaline phosphatase (sAP), urinary hydroxyproline/creatinine ratio (uOH-Prol/creatinine) and osteocalcin (sBGP), in two bone disorders characterized by an increase in bone remodelling, namely Paget's disease of bone and primary hyperparathyroidism (PHPT) and in two other bone diseases characterized by an increase in bone resorption without the concomitant increase in bone formation, hypercalcaemia of malignancy (HM) and involutional osteoporosis (IO). Serum BGP was increased in patients with Paget's disease of bone (6.7 +/- 3.1; n = 25; p less than 0.01) and in PHPT patients (8.3 +/- 5.3; n = 20; p less than 0.005) with respect to control patients (4.2 +/- 1.2 ng/ml; n = 12). Two subgroups of patients with high and normal levels of sBGP were found in both pathologies. Serum BGP was decreased in HM patients (2.1 +/- 1.7; n = 9; p less than 0.01) and in IO patients (1.9 +/- 1.4; n = 31; p less than 0.001). Two subgroups of patients with normal and low sBGP values were found in these two last disorders. A positive linear correlation was found between sBGP and sAP (y = 14.6x + 73.7; r = 0.44; p less than 0.05) and between sBGP and uOH-Prol/creatinine (y = 0.008x + 0.007; r = 0.67; p less than 0.001) in Paget's disease of bone.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Osteocalcin and bone remodelling in Paget's disease of bone, primary hyperparathyroidism, hypercalcaemia of malignancy and involutional osteoporosis. 278 49

Serum osteocalcin (BGP) is an osteoblast product that probably reflects the rate of bone formation. It is a potential marker of skeletal metastases and, to investigate this, BGP was measured by radioimmunoassay in the serum of normal subjects and patients with breast or prostate cancer. Significantly higher levels were found in patients with metastatic bone disease in comparison to both normal subjects (P less than 0.001) and patients with non-metastatic cancer (P less than 0.05 for breast cancer and less than 0.001 for prostate cancer). The range of values was wide. Levels were higher in sclerotic than lytic bone metastases (P less than 0.01) and lower in patients with hypercalcaemia (P less than 0.001). Serial measurements of BGP were made in 53 patients with skeletal metastases from breast cancer receiving systemic therapy. At 1 month BGP rose by greater than 0.5 ng/ml in 15/16 responding patients compared with 7/23 patients with progressive disease (P less than 0.01). Responding patients also showed a rise in the bone isoenzyme of alkaline phosphatase and a paradoxical deterioration in the bone scan appearance, both reflecting a flare in osteoblast activity. The early increase in responding patients was followed by a gradual decrease over subsequent months as the osteoblast reaction induced by systemic therapy subsided. We conclude that BGP measurements reflect a wide variability of bone formation rates in metastatic bone disease. Bone formation was usually increased, particularly when metastases were sclerotic in appearance, but in patients with hypercalcaemia the low BGP levels suggest uncoupling of bone resorption and formation. Serial measurements of BGP may be useful in monitoring response to treatment.
 ...
PMID:Osteocalcin: a potential marker of metastatic bone disease and response to treatment. 326 63

Treatment of secondary hyperparathyroidism and the osteodystrophy of predialysis chronic renal failure (CRF) with 1,25(OH)2D3 has been advocated by several authors, but also opposed by others for alleged renal toxicity. However, current concepts of the pathogenesis of the early occurrence of secondary hyperparathyroidism in predialysis CRF point to deficiency of 1,25(OH)2D3 as a primary factor. The aim of this study was to evaluate if administration of 1,25(OH)2D3 (0.25 microgram daily) in a dose which would not induce hypercalcemia, would improve humoral and bone histomorphometric parameters in predialysis CRF. 15 patients with predialysis CRF (mean age 51.2 +/- 16.9 years, range 13-73 years), serum creatinine 4.93 +/- 1.7 mg/dl, were treated with the vitamin D metabolite for an average of 16.2 +/- 11.3 months, at the end of which a transiliac bone biopsy for histomorphometry was performed. In addition, 23 patients comparable for age, serum creatinine and causes of renal failure, served as controls. Treatment did not induce hypercalcemia nor adversely modify the rate of decline of renal function. Alkaline phosphatase fell significantly while immunoreactive parathyroid hormone (iPTH) and osteocalcin showed a moderate, not significant, decrease. Compared to the control patients, the bone histomorphometric parameters active resorption surface and active osteoblastic surface were significantly lower and almost normalized by treatment. In conclusion, the study provides conclusive evidence of the absence of toxicity of the metabolite at the low doses employed, together with good therapeutic response on bone histology. Treatment at this dosage could be made in the early stages of predialysis CRF without need of close and continuous monitoring of serum biochemical parameters.
 ...
PMID:Treatment of secondary hyperparathyroidism of predialysis chronic renal failure with low doses of 1,25(OH)2D3: humoral and histomorphometric results. 349 62

Serum osteocalcin (BGP) is a new marker of bone turnover that reportedly evaluates bone formation. Thus, its measurement could assess the bone formation rate in tumor-associated hypercalcemia. We measured concentrations of BGP and other parameters of bone metabolism in 54 untreated hypercalcemic cancer patients as compared to 109 healthy subjects. Primary tumor sites were breast (19), lung (11), head and neck (6), multiple myeloma (3), kidney (2), and various (11) or multiple (2). Mean BGP levels were higher in the hypercalcemic subjects, 4.6 +/- 0.4 (SEM) ng/ml, than in the normal subjects, 3.6 +/- 0.1 ng/ml (p less than .05), and were normalized in the 22 patients who could be reevaluated after successful treatment of hypercalcemia with intravenous aminohydroxypropylidene diphosphonate (APD). There was no correlation of BGP levels with age, sex, or renal function. Compared with the Gaussian distribution in the normal subjects, there was a considerable scatter of the data in hypercalcemic patients, suggesting the existence of defined subgroups with abnormally low or abnormally high values. However, we found no significant relationship of BGP concentrations with tumor site or histology or with bone metastatic involvement. We found also no significant correlation between concentrations of serum BGP and total or ionized calcium, alkaline phosphatase, parameters of bone resorption, and indices of parathyroid function. In summary, serum BGP levels were slightly elevated in tumor-associated hypercalcemia and were normalized after successful treatment of hypercalcemia. More importantly, BGP concentrations varied widely even in the subgroups of patients with hypercalcemia accompanying massive bone metastatic involvement or in the patients without detectable skeletal metastases.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Serum osteocalcin (BGP) in tumor-associated hypercalcemia. 350 43

We administered high doses of calcitriol (up to 32 micrograms per day) to an infant with malignant osteopetrosis, in an attempt to stimulate bone resorption. The patient was placed on a low-calcium diet to prevent hypercalcemia. Measures of bone turnover increased during calcitriol therapy; hydroxyproline excretion rose from 140 to 1358 micrograms per milligram of creatinine per 24 hours, with parallel increases in the ratio of calcium to creatinine in the urine, urinary gamma-carboxyglutamic acid, serum osteocalcin, and serum alkaline phosphatase. A pretreatment bone-biopsy specimen contained no osteoclasts with ruffled borders, a feature of active osteoclasts. After 11 days of calcitriol, ruffled borders were noted. After three months, numerous osteoclasts with ruffled borders and associated bony disruption were evident. Before therapy, the patient's monocytes were incapable of in vitro bone resorption, but after calcitriol, their resorptive capacity was increased to 3.3 times control levels. These data demonstrate that calcitriol increased bone mineral and matrix turnover in our patient. However, during the three months of calcitriol therapy there was only slight clinical improvement in her severe disease. Early and sustained treatment with calcitriol may be useful in osteopetrosis.
 ...
PMID:Treatment of congenital osteopetrosis with high-dose calcitriol. 654 10

Impairment of calcium metabolism and low bone density have been found in hypothyroid adults. We investigated the effect of thyroid replacement therapy on calcium metabolism and bone mineralization in congenital hypothyroid (CH) infants and children. One hundred and 16 Caucasian CH consecutive patients were studied and were grouped according to their age: 23 patients at diagnosis, 20 at 3 mo, 24 at 6 mo, 25 at 12 mo and 24 at 36 mo. Thyroid replacement therapy was started at an initial dose of 6-8 micrograms/kg/day of L-thyroxine, and then decreased progressively. Calcium, phosphorus, magnesium, alkaline phosphatase (AP), parathyroid hormone (PTH) and osteocalcin (BGP) were measured as calcium metabolism indices. Bone mineral content (BMC) was measured at the mid-portion of the right radius AP, PTH and BGP concentrations were significantly higher in subjects at 3 mo of age (p < 0.05). This rise coincided with the end of the period of maximum dosage of L-thyroxine. Mild asymptomatic hypercalcemia was observed in 20 patients. All the other indices did not differ between age groups. BMC values and BMC annual increment were not different from those calculated for age-matched controls. We found that L-thyroxine replacement therapy does not alter bone mineralization of CH infants and children. Only a transitory increase of osteoblastic function was observed after the first few months of therapy.
 ...
PMID:Bone mineral metabolism and thyroid replacement therapy in congenital hypothyroid infants and young children. 756 Aug 9

We compared the effects of parathyroid hormone (PTH1-34) and parathyroid hormone-related protein (PTHrp1-34) on osteocalcin release in the isolated rat hindlimb and in intact and thyroparathyroidectomized (TPTX) rats. PTH1-34 suppressed osteocalcin release from perfused rat hindquarters, while PTHrp1-34 had no effect on osteocalcin release, despite comparable stimulation of cAMP production. Similarly, serum osteocalcin declined in the intact and TPTX animals by 5 h after a single dose of PTH1-34, while there was no response to PTHrp1-34. Chronic administration of PTH1-34 or PTHrp1-34 produced comparable hypercalcemia and hypophosphatemia in sham-operated and TPTX animals. Chronic PTH1-34 administration produced significant increases in serum osteocalcin both in the sham-operated rats and in the TPTX animals. However, in animals chronically treated with PTHrp1-34, there was no change at any time point in osteocalcin in either sham-operated or TPTX rats. These differences could be inherent or merely due to potency differences between the two peptides.
 ...
PMID:A comparison of the effects of parathyroid hormone and parathyroid hormone-related protein on osteocalcin in the rat. 757 14

Although calcitonin (CT) treatment has been shown to prevent bone loss in estrogen-deficient states, the function of endogenous CT in bone metabolism is not clearly established. To test the hypothesis that endogenous CT has a role in bone conservation, we compared the bone-resorbing effect of exogenous PTH between CT-deficient [thyroparathyroidectomized (TPTX)] and CT-sufficient [parathyroidectomized (PTX)] rats. Studies were carried out with two doses (30 and 40 pmol/h) of bovine PTH-(1-34) to examine dose responsiveness and with or without T4 replacement in TPTX rats to exclude the influence of thyroid function on the results. Sham-operated control rats received vehicle. At comparable hypercalcemia (mean +/- SEM, 13.6 +/- 0.8 vs. 12.7 +/- 1.0 mg/dl) after 3 days of sc infusion of 30 pmol/h PTH, serum CT levels were significantly (P < 0.05) higher in PTX rats (66.0 +/- 8.0 pg/ml) than in TPTX rats (17.7 +/- 4.3). CT-deficient TPTX rats showed a significant cancellous bone loss in the proximal tibia [bone volume (BV/TV), 4.2 +/- 1.0%] compared with control rats 10.4 +/- 1.2%) In contrast, there was no bone loss in CT-sufficient PTX rats (BV/TV, 10.9 +/- 0.5%). A similar difference in the serum CT level and more marked difference in BV/TV (0.9 +/- 0.3% vs. 8.1 +/- 1.3%) were observed between TPTX and PTX rats infused with 40 pmol/h PTH. The magnitude of bone loss in TPTX rats was not different between T4-supplemented and nonsupplemented groups. Unlike cancellous bone, the PTH-induced decrease in the cortical thickness of the tibia was comparable in TPTX and PTX rats. The extent of increase in serum osteocalcin after PTH infusion was not different between TPTX and PTX groups. These results indicate that in the rat, endogenous CT has a protective effect against PTH-stimulated cancellous bone loss, but not cortical bone loss.
 ...
PMID:Endogenous calcitonin attenuates parathyroid hormone-induced cancellous bone loss in the rat. 783 11

Hypercalcemia is a common complication in continuous ambulatory peritoneal dialysis (CAPD) patients treated with calcium-containing phosphate binders and using the standard dialysate calcium concentration of 3.5 mEq/L (SCa). Lowering the dialysate calcium was proposed to overcome this problem. The current randomized controlled multicenter study was designed to investigate efficiency and safety of a low calcium dialysate (2.00 mEq/L; LCa) compared with SCa (3.5 mEq/L) in CAPD patients. After an 8-week run-in period, 103 stable CAPD patients, 68 men, 35 women, aged 54.5 years (range, 20 to 77)) were randomly allotted to treatment with either LCa or SCa. All patients received calcium carbonate as oral phosphate binder to achieve serum phosphate levels < 6.2 mg/dL. If persistent hypercalcemia arose, CaCO3 was replaced by Al(OH)3 until normocalcemia was achieved. All patients received 0.25 microgram calcitriol/d. Parameters monitored included total and ionized serum calcium, serum phosphate, phosphate binder intake, incidence of hypercalcemia, serum aluminium, intact parathyroid hormone (1,84PTH), osteocalcin, alkaline phosphatase, bone mineral density and hand skeletal x-ray. Primary end points were (a) number of hypercalcemic episodes, (b) tolerated doses of calcium-containing phosphate binders, and (c) 1,84PTH. After 6 months of therapy, total and ionized calcium were lower in LCa patients (total Ca:9.6 v 10.08 mEq/L, P = 0.005; iCa: 4.76 v 5.15 mg/dL; P = 0.013). In the LCa group, significantly fewer episodes of hypercalcemia were recorded (total S-calcium > 10.8 mg/dL: LCa 24 v SCa 86 episodes; P < 0.005). Use of LCa permitted the administration of more CaCO3 (mean daily tablet number: LCa, 5.9 v SCa, 4.2; P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Low dialysate calcium in continuous ambulatory peritoneal dialysis: a randomized controlled multicenter trial. The Peritoneal Dialysis Multicenter Study Group. 787 24


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>