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)

A sensitive radioreceptor assay for 1alpha,25-dihydroxyvitamin D3 (1alpha,25-(OH)2D3) is utilized to quantitate the circulating concentration of this sterol in experimental animals and humans. When weanling rats are grown for 2 weeks on low calcium or low phosphate diets, limited availability of either ion elicits a five-fold increase in the plasma level of 1alpha,25-(OH)2D3. The enhancement of 1alpha,25-(OH)2D3 in calcium deficiency is dependent upon the presence of the parathyroid and/or thyroid glands, which is consistent with parathyroid hormone (PTH) mediation of this effect. In contrast, the response to phosphate deficiency is independent of these glands and may result from a direct action of low phosphate on the renal synthesis of 1alpha,25-(OH)2D3. Studies in humans indicate that the normal level of 1alpha,25-(OH)2D is 2.1--4.5 ng/100 ml plasma. Patients with chronic renal failure have markedly lower circulating 1alpha,25-(OH)2D and this kidney hormone is undetectable in anephric subjects, but returns to normal within 1 day after successful renal transplantation. Hypoparathyroidism and pseudohypoparathyroidism are associated with reduced plasma 1alpha,25-(OH)2D while patients with primary hyperparathyroidism have significantly elevated sterol hormone levels. Thus, from measurements in rats and humans, it appears that circulating 1alpha,25-(OH)2D3 is regulated by PTH and/or phosphate and that abnormal plasma 1alpha,25-(OH)2D3 is a part of the pathophysiology of renal osteodystrophy and parathyroid disorders.
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PMID:The assay of 1alpha,25-dihydroxyvitamin D3: physiologic and pathologic modulation of circulating hormone levels. 21 27

The amounts of total hydroxyproline (THP), free hydroxyproline (FHP) and non-dialysable hydroxyproline (NDHP) excreted in the urine by six patients with chronic renal failure who received kidney transplants and six patients with primary hyperparathyroidism were studied. Following transplantation three of the four patients with radiological evidence of hyperparathyroidism developed hypercalcaemia and excreted more than 360 mumol THP/24 hours on at least one occasion. The remaining patients were normocalcaemic and excreted less THP and a higher proportion of NDHP. In all patients with primary hyperparathyroidism, THP excretion fell after adenoma removal but there was an increased excretion of NDHP:THP. It is suggested that studies of hydroxyproline excretion may contribute to clinical assessment of healing of renal osteodystrophy and involution of the parathyroid glands after renal allograft transplantation.
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PMID:Hydroxyproline excretion following renal transplantation: comparison with values found in primary hyperparathyroidism. 34 3

The limited role of bone scanning in the diagnosis of metabolic bone disease might be considerably improved by accurate quantification of skeletal uptake of the radiopharmaceutical. Using a standard shadow-shield whole-body monitor, we have measured whole-body retention (WBR) of Tc-99m HEDP up to 24 hr in 11 patients with renal osteodystrophy (mean WBR 88.6% at 24 hr); in ten patients with Paget's disease (mean 56.9%); in seven patients with osteomalacia (mean 40.7%); in five patients with primary hyperparathyroidism (mean 50.7%); in four patients with osteoporosis (mean 21.2%); and in 12 normals (mean 19.2%). The osteoporotic group could not be differentiated from the normal group, but the other groups were significantly different from the normal group at 24 hr (p less than 0.002), and each individual rest for the 24-hr WBR of Tc-99m HEDP in these groups lay outside our normal range. This test may, therefore, provide a sensitive means of detecting conditions with increased bone turnover. We obtained measurements of plasma activity of Tc-99m HEDP in these patients up to 24 hr, and 4-hr bone to soft-tissue ratios from bonescan images, but little additional information resulted.
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PMID:The use of whole-body retention of Tc-99m diphosphonate in the diagnosis of metabolic bone disease. 56 41

Autotransplantation of the parathyroid to the forearm has been performed in eight patients following total or subtotal parathyroidectomy. The mass of gland implanted was approximately one half that used in other series. Bilateral simultaneous parathormone levels drawn at three months after autografting several higher levels in the autografted arm in every patient examined. Replacement calcium and vitamin D therapy were withdrawn from two patients within eight months after transplant, and it is anticipated that all patients will be off maintenance at 12 months. Electron and light microscopy of grafted tissue has revealed viable glands with intracellular secretory granules, many mitochondria, and little fat. Indications for autotransplantation include patients with refractory renal osteodystrophy, reoperations for primary hyperparathyroidism, and extensive extirpative cancer surgery of the head and neck.
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PMID:Parathyroid autotransplantation. 84 44

Primary hyperparathyroidism is a common condition infrequently complicated by renal stones and overt bone disease. Most cases are asymptomatic or have vague, nonspecific symptoms. There is considerable debate as to whether mild or asymptomatic cases should be managed surgically or conservatively. Important chromosomal abnormalities have now been demonstrated in some parathyroid adenomas. Renal osteodystrophy remains a difficult condition to treat once it is fully established. The use of vitamin D metabolites in the early stages of renal failure and the maintenance of a normal serum calcium and phosphate appear to prevent the development of secondary hyperparathyroidism. Further studies are required to ascertain the optimum way of using vitamin D metabolites and how best to reduce serum phosphorus.
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PMID:Primary hyperparathyroidism and renal osteodystrophy. 188 4

Bone metabolic homeostasis is regulated by a number of hormones and local modulators, and the study of these factors has been of major help in our understanding of bone disease. However, these parameters do not, in a strict sense reflect the metabolic and biochemical changes in the diseased bone tissue. Thus, there is a great interest in the study of biochemical specific "markers" of bone metabolic processes, namely of bone formation and bone resorption. Alkaline phosphatase, osteocalcin, osteonectin, and procollagen type I propeptides are the currently known markers of bone formation, whereas urinary hydroxyproline and hydroxylysine glycosides, plasma tartrate resistant acid phosphatase, and urinary hydroxy-pyridinium crosslinks of collagen are considered markers of bone resorption. In this paper, we review the background work on each of these markers, and subsequently give an overview of the currently available data on their usefulness in metabolic bone diseases, namely in Paget's disease of bone, primary hyperparathyroidism, osteoporosis, and renal osteodystrophy.
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PMID:Biochemical markers of bone metabolism. 192 60

Most RIAs of serum bone gla-protein (BGP; also called osteocalcin) used for clinical investigation are based on bovine BGP for standard, tracer, and immunogen because of the homology between bovine and human BGP. However, ovine BGP differs from human BGP by only five amino acids, being identical from residues 11 to 49, as compared with homology at residues 20-49 between bovine and human BGP. In screening various anti-ovine BGP polyclonal anti-sera we selected one (R310) that exhibits apparently complete cross-reactivity with human BGP, as assessed by dilutions of 13 human sera from normal subjects and from patients with bone disease. This RIA gave a 42% binding at a 10,000-fold final dilution, with intra- and interassay variations less than 7% and 11%, respectively. Gel-filtration chromatography of human serum showed a single immunoreactive peak. Synthetic fragments of human BGP 1-10, 7-19, 25-37, and 37-49 were not recognized by R310, suggesting that either a mid-molecule region or a conformational epitope was its target. Using this RIA, we determined that serum BGP increased with age in women (P less than 0.02), by a mean of 90% from ages 30 to 70 years. Serum BGP was also increased in patients with primary hyperparathyroidism, renal osteodystrophy, and Paget's disease. In contrast with the "normal" concentrations of BGP detected with an anti-bovine BGP antiserum (R102), serum BGP was increased in patients with postmenopausal osteoporosis as measured with the R310 ovine assay, suggesting a greater sensitivity for the latter assay.
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PMID:Measurement of serum bone gla-protein (BGP) in humans with an ovine BGP-based radioimmunoassay. 220 2

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

Twenty-nine consecutive patients with suspected primary hyperparathyroidism were examined preoperatively using ultrasound, sonographically guided fine needle aspiration, and aspirate immunostaining for PTH. In 25 patients, localization of enlarged parathyroid glands was successful. In 2 patients, the tumors were located retrosternally and, thus, could not be detected by ultrasound. One patient had a multinodular goiter which impeded localization. In 1 patient with renal osteodystrophy, 2 enlarged parathyroid glands in the neck were not visualized preoperatively. Cytology was not diagnostic, although some cytological features were suggestive of parathyroid cells. Immunostaining of the aspirated smears for PTH, however, correctly diagnosed all preoperatively localized lesions. Ultrasound should be the routine procedure of choice for preoperative localization of abnormal parathyroid glands in primary hyperparathyroidism. Fine needle aspiration and immunocytochemistry can supply confirmation, if necessary.
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PMID:Parathyroid localization. 243 Sep 91

A retrospective analysis was undertaken to better define the clinical presentation and therapy of patients with secondary hyperparathyroidism and the timing of surgical removal of the parathyroid glands in secondary hyperparathyroidism. Sixty-eight patients with end-stage renal disease (ESRD) underwent 74 parathyroid procedures over a 10-year period. There were 38 per cent women and 62 per cent men in this population--the same proportion of men and women with ESRD. These proportions are reversed when compared with patients with primary hyperparathyroidism. The mean time between initiation of dialytic therapy and parathyroidectomy was 5.4 years. Preoperative mean serum calcium and phosphorus levels were 10.1 +/- 0.2 and 6.1 +/- 0.2 mg/dl, respectively. All patients were symptomatic and 60 per cent of the patients had at least two symptoms before surgery. Renal osteodystrophy was the most common symptom (74%), whereas pruritus was noted in 65 per cent of this population. Patients underwent either subtotal (88%) or total (12%) parathyroidectomy with autotransplantation. Six patients required reoperation: five for recurrent disease (2 to 5 years after the initial surgery) and one for persistent disease. All patients were symptomatically improved after the surgery. Complications included the following: transient hoarseness (7%), hypocalcemia requiring calcium, and/or vitamin D therapy (32%) for 6 months after surgery. This analysis demonstrates that although the initial therapy of secondary hyperparathyroidism is medical, surgical therapy should be instituted before multiple symptoms develop in the ESRD population.
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PMID:Secondary hyperparathyroidism. The role of surgery. 272 73


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