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)

Two-site immunoradiometric assay for human parathyrin (PTH1-84) is specific for the intact, secreted, biologically active 84 amino peptide. This system incorporates two-different polyclonal antibodies to human intact PTH and has several technical advantages for use. This assay could detect a wide range of PTH in patients with hypo-, hyperparathyroidism, chronic renal failure and hypercalcemia with malignancy, especially distinguishing the level of human intact PTH in hypoparathyroidism from in normal.
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PMID:[Basic studies on an immunoradiometric assay system for human parathyrin (intact PTH1-84)]. 317 64

The operative management of patients with hyperparathyroidism is controversial. Higher rates for persistent hypercalcemia and postoperative hypoparathyroidism are seen in multiple-gland hyperplasia and in bilateral neck exploration. Hyperparathyroid patients undergoing unilateral neck exploration with removal of a single parathyroid adenoma have a rapid clearance of parathyroid hormone (PTH) that declines to undetectable levels within hours after successful parathyroid surgery. We have taken advantage of a sensitive immunoradiometric assay (IRMA) for the secreted biologically active, intact PTH-(1-84) molecule and demonstrated a decline of PTH to less than 40% of baseline values 15 minutes after successful parathyroid adenomectomy in 12 patients. Intraoperative measurement of PTH by modification of this IRMA may complement surgical skill and histopathologic information and has the potential for providing guidance regarding the extent of neck exploration necessary for determining surgical care of hyperparathyroidism.
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PMID:Intraoperative measurement of parathyroid hormone in the surgical management of hyperparathyroidism. 319 39

Endocrinologic disorders occasionally manifest themselves by their associated or induced cutaneous abnormalities. In some instances the initial and most prominent complaints of the patient are related to alterations in the skin, and thus the dermatologist will at times be the first physician consulted. In this article we describe the cutaneous lesions that occur in patients with acromegaly, hypopituitarism, hypothyroidism, hyperthyroidism, diabetes mellitus, glucagonomas, hypercalcemia, hypoparathyroidism, and fibrous dysplasia. In addition, we also discuss the role of the skin in vitamin D metabolism. Whenever possible and where known, we have attempted to point out the pathophysiologic mechanisms that account for the cutaneous changes.
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PMID:Endocrine-skin interactions. Cutaneous manifestations of pituitary disease, thyroid disease, calcium disorders, and diabetes. 332 73

Intact parathormone (PTH 1-84) was measured with a new immunoradiometric method in serum from 83 children and adults with various abnormalities of calcium metabolism. The results were compared with those of an assay of midregional PTH fraction (44-68). Both measurements discriminated well between normal controls and patients with primary or secondary hyperparathyroidism. In patients in chronic renal failure intact PTH measurement was best for demonstrating parathyroid secretion. An important advantage of the new method is in the diagnosis of PTH hyposecretion in hypoparathyroidism and of tumour hypercalcaemia, which is not possible by mid-regional PTH determination. Intravenous injection of calcium (2 mg/kg over 5 min) and of synthetic PTH fragment (6 U/kg 1-38 hPTH over 2 min) caused a reduction in intact serum-PTH to about half the initial value after five minutes. Measuring intact PTH is thus a suitable method for determining both raised and decreased parathyroid secretion in disease and in the course of function tests. It is simple to perform, subject to only minor interference, and thus suitable also as a routine laboratory test.
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PMID:[Intact serum parathormone (PTH 1-84). A suitable parameter for the diagnosis of calcium metabolism disorders]. 334 39

In 23 patients with hypoparathyroidism or pseudohypoparathyroidism treated with vitamin D, and in whom the dosage was adjusted downward or upward in response to hypercalcemia or hypocalcemia respectively, assays of serum 25-hydroxyvitamin D (25-OHD) were carried out in addition to the usual serum calcium assays. In 120 assays there was a significant correlation between serum 25-OHD levels and serum calcium levels (corrected for serum albumin). There was, however, no clear distinction between the 25-OHD levels of patients who were hypocalcemic, normocalcemic or hypercalcemic. The highest serum 25-OHD level found in a hypocalcemic patient was 1193 nmol/L and the lowest serum 25-OHD level found in a hypercalcemic patient was 605 nmol/L. It was not possible to predict subsequent episodes of hypocalcemia or hypercalcemia from the serum 25-OHD levels. The 25-OHD assay was found to be useful only in checking compliance. We conclude that the assay of serum 25-OHD is of no more value than serum calcium alone in the management of compliant patients.
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PMID:The value of serum 25-hydroxyvitamin D measurements in hypoparathyroid and pseudohypoparathyroid patients treated with calciferol. 348 79

The response of circulating 1,25-dihydroxyvitamin D [1,25-(OH)2D] to challenge with vitamin D treatment both before and after 7-10 days of prednisone therapy (25 mg/day) was investigated in five anephric subjects, six patients with chronic renal failure (CRF), two patients with vitamin D intoxication and four patients with hypoparathyroidism. In anephric subjects serum 25-hydroxyvitamin D [25-(OH)D] rose from 58 +/- 48 (SD) to 377 +/- 221 (SD) nmol/l after administration of 150 micrograms of 25-(OH)D3 for 1 month. Serum 1,25-(OH)2D, which was barely detectable in only two out of five patients under basal conditions, rose to 30 +/- 21 pmol/l after 2 weeks of therapy with 25-(OH)D3, but fell to 10 +/- 5 pmol/l during prednisone treatment. In CRF patients circulating 1,25-(OH)2D rose from 37 +/- 24 to 58 +/- 24 pmol/l during 25-(OH)D3 therapy, but fell to 41 +/- 31 pmol/l during prednisone treatment. In two patients with rheumatoid arthritis, hypercalcaemia due to vitamin D intoxication was associated with raised levels of 1,25-(OH)2D (288 and 317 pmol/l). Administration of prednisone resulted in suppression of 1,25-(OH)2D levels (132 and 96 pmol/l respectively) and reduction of serum calcium to within the normal range. In the hypoparathyroid patients prednisone therapy did not affect circulating 25-(OH)D levels but serum 1,25-(OH)2D fell from 192 +/- 42 to 117 +/- 23 pmol/l and serum calcium from 2.41 +/- 0.21 to 2.20 +/- 0.05 mmol/l.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Extrarenal synthesis of 1,25-dihydroxyvitamin D: sensitivity to glucocorticoid treatment. 349 10

Primary hyperparathyroidism in the neonate is a rare and often fatal disorder. These infants typically display severe hypercalcemia, respiratory distress, muscular hypotonia, and skeletal demineralization. They are usually diagnosed within the first three months of life and have hyperplasia of the four parathyroid glands. Twenty-nine infants with primary hyperparathyroidism are reported in the literature. Mortality is 87.5% in medically managed patients and 24% in surgically managed patients. Surgical management has not been satisfactory, in that recurrent hypercalcemia has been encountered in most patients undergoing subtotal parathyroidectomy, and total parathyroidectomy has resulted in the need for lifelong calcium and vitamin D supplementation. We have recently cared for a term newborn female in whom the diagnosis of primary hyperparathyroidism was made clinically on the second day of life, and later was confirmed biochemically. The baby underwent neck exploration on the 11th day of life and was successfully treated with total parathyroidectomy and parathyroid autotransplantation. Although initially rendered eucalcemic, the infant subsequently developed recurrent hypercalcemia requiring the removal of some of the autograft. Currently, the child is more than 2 years following surgery, growing well, and off all medication. The world literature is reviewed in this report of one of the first and the youngest infants, to our knowledge, to undergo parathyroid autotransplantation. In view of its success in avoiding the complication of repeated neck exploration for recurrent hyperparathyroidism or the creation of permanent hypoparathyroidism, we recommend this surgical approach for the rare neonate with primary hyperparathyroidism.
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PMID:Primary hyperparathyroidism in infancy. 352 45

We studied a young woman with surgical hypoparathyroidism who, on her usual maintenance dose of calcitriol, developed hypercalcaemia 9 d postpartum when lactation was established. Serum values of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) values were very high (127 pg/ml). The patient remained without exogenous calcitriol treatment for 40 d, during which time serum 1,25(OH)2D3 levels remained within the normal range and serum calcium fell with a half-time of 27 d. The requirements for calcitriol increased to antepartum levels when lactation had ceased. There was a close negative correlation between requirements for calcitriol and serum PRL values. After weaning, an episode of hypercalcaemia was induced by increasing the dose of calcitriol. On stopping calcitriol the serum 1,25(OH)2D3 fell to low values (4 pg/ml) within 2 d and serum calcium fell with a half-time of 3 d, necessitating the early reintroduction of calcitriol. We conclude that in hypoparathyroidism exogenous vitamin D requirements fall during lactation because of enhanced endogenous production of 1,25(OH)2D3. The lactation-associated increase in circulating 1,25(OH)2D3 concentrations thus results from a parathyroid hormone-independent mechanism, possibly by an effect of PRL on the 1 alpha-hydroxylase.
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PMID:Remission of hypoparathyroidism during lactation: evidence for a physiological role for prolactin in the regulation of vitamin D metabolism. 366 23

One group has reported hypocalcemic individuals in families affected with familial benign hypercalcemia (FBH), suggesting either that FBH is merely an extreme of normality or that hypocalcemia is independently inherited in that kindred. To test these hypotheses, we examined the distributions of serum total calcium (Ca) values in 260 normal adults and 171 adult individuals in 21 FBH kindreds. We excluded from analysis the 21 adult probands, leaving 85 apparently affected persons (Ca, greater than 10.1 mg/dL or greater than 2.52 mmol/L) and 65 apparently unaffected individuals (Ca, less than or equal to 10.1 mg/dL or less than or equal to 2.52 mmol/L). Five FBH family members were hypocalcemic (less than 8.9 mg/dL or less than 2.22 mmol/L); of these, 3 had hypoproteinemia or hypoalbuminemia, 1 had surgical hypoparathyroidism, and 1 was pregnant (and thus excluded from further analysis). Histogram analysis suggested a bimodal distribution of Ca in the FBH families, and familial serum Ca levels were significantly elevated (P less than 0.001, rank sum). When only apparently unaffected family members were compared with normal individuals with serum Ca of 10.1 mg/dL or 2.52 mmol/L or less, the distributions were virtually identical. Our results indicate that hypocalcemia in members of families with FBH is of sporadic nongenetic origin. Furthermore, FBH is not an extreme of the normal distribution, but, instead, a clear disturbance with its own distribution about a supranormal mean serum calcium value.
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PMID:Distribution of serum calcium values in patients with familial benign hypercalcemia (hypocalciuric hypercalcemia): evidence for a discrete genetic defect. 366 74

The performance and clinical utility of a 'C-terminal' parathyroid hormone (PTH) radioimmunoassay (Dac-Cel, Wellcome Diagnostics) is described. Parathyroid hormone, as measured by the Dac-Cel method, is stable in whole blood samples for at least 24 h. 84% of patients with hypercalcaemia due to primary hyperparathyroidism have values above the upper limit seen in normocalcaemic subjects (0.5 micrograms/L), with detectable serum PTH demonstrable in the remaining 16%. In patients with hypocalcaemia due to hypoparathyroidism serum PTH was undetectable in 73% and 'inappropriately' low in the remainder. In 50% of patients with malignancy-associated hypercalcaemia serum PTH was undetectable, but was above 0.5 micrograms/L in 13%. Increased PTH concentrations were invariably found in patients with renal failure. The Dac-Cel method is a reliable and robust technique for measurement of PTH and in conjunction with determination of calcium facilitates the diagnosis of primary parathyroid disorders. Caution is required in the interpretation of PTH measurements in patients with renal failure; the significance of detectable PTH in some patients with malignancy-associated hypercalcaemia is not clear.
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PMID:Performance and clinical utility of a commercially available 'C-terminal' PTH assay. 376 72


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