Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0221002 (primary hyperparathyroidism)
 4,921 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have examined circulating concentrations of a parathyroid hormone-like peptide (PLP) in patients with malignancies and in patients with hyperparathyroidism. The radioimmunoassay employed reacts with synthetic amino-terminal fragments of PLP but not with parathyroid hormone. Elevated plasma PLP concentrations were observed in 50% of patients with malignancy and hypercalcemia and in 15% of normocalcemic cancer patients, mean values being higher in the former group. Detectable plasma PLP concentrations were found in 2 of 39 control subjects. In 2 patients with breast cancer plasma PLP declined concomitantly with a reduction in tumor burden. Adenocarcinoma of the breast and squamous cell carcinomas were most frequently associated with high plasma PLP levels although a variety of histologic types were represented. The presence of metastases on bone scans did not correlate with either the severity of hypercalcemia or the extent of PLP elevation. Increased concentrations of plasma PLP were also observed in 4 of 20 patients with primary hyperparathyroidism and in 5 of 16 patients with chronic renal failure and secondary hyperparathyroidism. Gel filtration analysis of immunoreactive PLP in plasma from 2 hypercalcemic breast cancer patients revealed heterogeneity, with, in each case, both large (greater than 15 kD) and small (6-7 kD) molecular weight amino-terminal moieties. The results document the presence of PLP in the circulation of patients with cancer and are consistent with a pathogenetic role for PLP in the hypercalcemia of malignancy irrespective of whether skeletal metastases have occurred. PLP may also contribute to the skeletal and/or renal manifestations of hyperparathyroid states.
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PMID:Circulating concentrations of parathyroid hormone-like peptide in malignancy and in hyperparathyroidism. 231 98

The vitamin D endocrine system, besides its traditional role in mineral metabolism, also affects the immune system. A recent study demonstrated that vitamin D supplementation restored a blunted delayed hypersensitivity response (DH) in elderly vitamin D-deficient subjects. In the present study the DH, as measured by the tuberculin test (PPD), was studied in two groups of patients with a disturbed vitamin D system, i.e. primary hyperparathyroidism (HPT) and secondary HPT due to chronic renal failure. A significant reduction in DH was found in the patients with chronic renal failure when compared to control subjects (4.1 +/- 5.3 vs 12 +/- 9.3 mm, p less than 0.05) whereas only a non-significant tendency to a reduced DH was seen in the HPT patients (9.5 +/- 9.2 mm). Treatment with alphacalcidol, a synthetic analogue to the active vitamin D metabolite over 3-6 months did not affect the DH in any of the hyperparathyroid patient groups. Thus it seems likely that other factors than vitamin D were involved in their reduced DH response.
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PMID:Delayed hypersensitivity in primary and secondary hyperparathyroidism. Treatment with active vitamin D. 236 23

Patterns of intact (1-84) parathyroid hormone (intact PTH) elimination and subsequent recovery of parathyroid function were studied in 12 patients undergoing parathyroidectomy. Nine patients had primary hyperparathyroidism (HPT), with single gland disease in 6 and multiple gland disease in 3. Two patients had subtotal parathyroidectomy for HPT secondary to chronic renal failure and 1 underwent excision of a hyperfunctioning parathyroid autograft. Using a sensitive 2-site immunochemiluminometric assay, serum intact PTH levels were measured preoperatively, intraoperatively, and postoperatively. A dual phase pattern of hormone clearance was found in 10 of the 12 patients, including the patient undergoing autograft excision. A monoexponential clearance pattern was seen in the remaining 2 patients, both of whom had subtotal parathyroidectomies for multiple gland disease. In the patients with primary HPT due to single gland disease, the early phase of intact PTH clearance had a half-life (T1/2) of 3.3 (+/- standard deviation 0.9) minutes and a late T1/2 of 96.4 (+/- standard deviation 92.7) minutes. Calculation of decay curves and half-lives for the patients undergoing subtotal parathyroidectomy was more difficult because of the inherent uncertainty in determining time zero. Nevertheless, in all but 2 patients, the clearance pattern was biexponential and the T1/2 measurements were very similar to those encountered in patients with single-gland disease. In the 2 patients with monoexponential clearance, the T1/2 figures were 86.7 minutes and 26.7 minutes, respectively. In the patients undergoing parathyroidectomy for primary HPT, levels of intact PTH were lowest at 1-3 hours after surgery, recovering to normal in the majority of patients by 18-40 hours.
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PMID:Study of intact (1-84) parathyroid hormone secretion in patients undergoing parathyroidectomy. 236 38

11 cases of primary hyperparathyroidism were seen during 1975-1988. Follow up has varied from 1-10 years. Renal disease in the form of renal calculi and nephro-calcinosis was observed in nine cases (81.8%). Two presented in chronic renal failure and required dialysis. Bone disease was found radiologically in six patients (54.5%); two had bone cysts in multiple bones while all six had subperiosteal bone erosion. Hypertension was found in three patients (27.3%). Proximal myopathy was observed in two cases (18.1%). One patient each presented with hypercalcaemic crisis, chondrocalcinosis and acute pancreatitis. The calcification of blood vessels and cornea was seen in two cases.
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PMID:Primary hyperparathyroidism. 238 Jan 35

A sensitive radioimmunoassay (RIA) for 1 alpha,25-dihydroxyvitamin D [1 alpha,25(OH)2-D] with a double antibody (DAB) separation technique to separate free from bound antigen has been developed. The hormone was extracted from 1 ml serum or plasma by Extrelut columns and normal phase high performance liquid chromatography and quantitated in the DAB-RIA. The detection limit of the assay was 3.75 ng/l. The intraassay variation coefficients were 15.9% and 10.5% for samples with 1 alpha,25(OH)2D3 concentrations of 54 ng/l and 130 ng/l, respectively. The interassay variation coefficients were 18.0% and 16.7% for these two concentrations. Mean (and SD) values for 1,25(OH)2D in serum of 40 healthy subjects and 38 patients with chronic renal failure who did not receive 1,25(OH)2D3 were 62.8 ng/ml (22.2) and 12.4 ng/ml (9.8), respectively. The mean value for 7 patients with primary hyperparathyroidism was 66.5 ng/ml (35.8) before surgery. These results compared well with those of an established charcoal-based RIA. Compared to charcoal-based RIAs, the DAB-RIA is faster and requires less laborious assay procedures.
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PMID:Development of a double antibody radioimmunoassay for quantitation of 1 alpha,25-dihydroxyvitamin D. 239 7

To study the circulating forms of parathyroid hormone (PTH), sera from 5 patients with primary hyperparathyroidism (PHP) and 12 patients with secondary hyperparathyroidism due to chronic renal failure (SHP) were submitted to gel filtration chromatography. The eluent samples were analyzed using two sequence-specific radioimmunoassays (RIA), one amino-terminal (NH2), the other carboxyl-terminal (COOH). The results obtained with the NH2 RIA showed a single molecular form in both groups co-eluting with the intact hormone. The COOH assay identified several molecular forms with a broader distribution in the SHP patients. These results confirm the diagnostic superiority of the NH2 assay under both conditions.
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PMID:Circulating molecular forms of parathyroid hormone in primary and secondary hyperparathyroidism. 263 48

In normal individuals, 1,25-dihydroxyvitamin D (1,25-D) levels regulate calcium (Ca) absorption according to Ca intake; its synthesis is stimulated by low Ca intake, probably via increased parathyroid hormone (PTH) secretion, to increase Ca absorption, and suppressed during high intake to reduce Ca absorption. The body also adapts Ca absorption in response to renal Ca excretion, and phosphate absorption in response to phosphate intake. These adaptations may fail or be impaired in certain diseases. In disorders of overadaptation, the intestinal tract absorbs excessive amounts of Ca due to overproduction of 1,25-D, as in absorptive hypercalciuria, sarcoidosis, primary hyperparathyroidism, and tumoral calcinosis. Intestinal hyperabsorption and hypercalciuria may occur on both low- and high-Ca diets. Primary hyperparathyroidism and hypoparathyroidism are bihormonal, related to over- and underproduction, respectively, of both 1,25-D and PTH. Underadaptation disorders are typically related to low 1,25-D synthesis or resistance to this metabolite; examples include postmenopausal osteoporosis, chronic renal failure, and osteomalacia. Many of these adaptational disorders can be relieved or improved by manipulating Ca, phosphate, sodium, or protein intake or by administering exogenous 1,25-D. Overabsorption of Ca and other substances, such as oxalate, may be responsible for Ca nephrolithiasis. Hypocitraturia (which may be a complication of certain diseases or the result of unbalanced diet or excessive exercise), diets high in readily metabolizable sugars and purine-rich proteins (meat, poultry, and fish), and low fluid intake can all contribute to stone formation. Various regimens may reduce the risk of Ca nephrolithiasis.
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PMID:Calcium metabolism. 268 27

Parathyroid hormone (PTH) has been shown in vitro to enhance erythrocyte osmotic fragility (EOF) and has been incriminated as a factor in the anaemia seen in patients with primary hyperparathyroidism and in patients with renal disease and secondary hyperparathyroidism. Enhanced EOF has also been shown in patients with chronic renal failure but did not correlate with PTH levels. We studied a group of patients with primary hyperparathyroidism with and without anaemia, and patients with secondary hyperparathyroidism and anaemia. We found that EOF studies in these patients did not differ from normal control groups and that there was no relation between PTH, EOF, and haematocrit in either study group. We conclude that PTH over a range of concentrations seen in vivo does not affect erythrocyte osmotic fragility or cause anaemia.
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PMID:Parathyroid hormone and anaemia--an erythrocyte osmotic fragility study in primary and secondary hyperparathyroidism. 281 31

The skeletal manifestations of hyperparathyroidism are due to the stimulation of osteoclast-mediated bone resorption by high circulating concentrations of parathyroid hormone (PTH). Since diphosphonates inhibit PTH-mediated bone resorption, we assessed the effects of clodronate in 42 patients with hypercalcaemia and increased bone resorption due to primary hyperparathyroidism (20 patients), secondary hyperparathyroidism in chronic renal failure (12 patients on haemodialysis replacement therapy) and tertiary hyperparathyroidism following successful renal transplantation (10 patients). Clodronate (0.8-1.6 g daily by mouth or 300 mg given as an intravenous infusion following five consecutive dialysis treatments) significantly decreased serum calcium and biochemical indices of bone resorption in the three groups studied. In primary and tertiary hyperparathyroidism, serum calcium values remained above the upper limit of the reference range despite suppression of bone resorption due to the unopposed effect of PTH on renal tubular reabsorption of calcium. Prolonged treatment (3 months) was associated with a partial recurrence of hypercalcaemia in 8 of 12 patients with primary hyperparathyroidism despite continued effects on bone resorption, possibly due to a secondary decrease in bone formation. These studies indicate that clodronate is capable of suppressing PTH-mediated bone resorption in disorders of parathyroid secretion and may prove to be a useful adjunct in their medical management.
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PMID:Clodronate in the medical management of hyperparathyroidism. 296 58

We describe the application of thallium-technetium subtraction scintigraphy in nine patients with failed previous parathyroid surgery or with tertiary hyperparathyroidism due to chronic renal failure. The technique successfully located all adenomas, but only 45% of hyperplastic glands. The series included three abnormal glands located retrosternally. The technique appeared to be more useful in patients with primary hyperparathyroidism than in tertiary hyperparathyroidism, possibly related to differences in gland mass. We conclude that this method of scintigraphy is a valuable adjunct to the management of patients with parathyroid disorders, particularly those requiring revision surgery.
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PMID:Thallium-technetium subtraction scintigraphy as an aid to parathyroid surgery. 298 65


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