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)

The metabolic bone disease associated with chronic renal failure has been described collectively by the terms "renal osteodystrophy" or "renal-glomerular-osteodystrophy" and consists of osteomalacia, osteitis fibrosa, and osteosclerosis. The skeletal abnormalities may occur either alone or in combination with one another. An increased concentration of circulating immunoreactive-parathyroid hormone (i-PTH) is a recognized feature of patients with chronic renal failure, and the values are usually much higher than those found in patients with primary hyperparathyroidism associated with a parathyroid adenoma. It must, however, be recognized that the high circulatory concentrations of parathyroid hormone found in patients with chronic renal failure are of immunoassayable material which may or may not be of biological significance in respect of activity. A disturbance in the homeostatic control mechanism governing parathyroid hormone, the secretion rate, its metabolism, and target organ resistance to its action are of major importance in the pathogenesis of some aspects of the metabolic bone disease in patients with chronic renal failure. The pathogenesis of the secondary hyperparathyroidism of chronic renal failure, however, also involves disturbances in cholecalciferol metabolism, phosphate retention, and the uremic state per se.
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PMID:Secondary hyperparathyroidism in chronic renal failure. 626 38

The disappearance of plasma PTH after parathyroidectomy was assessed in patients with primary hyperparathyroidism and normal renal function, chronic renal failure or restored renal function (after transplantation). Plasma PTH levels were determined by renal cytochemical bioassay and by midregion and carboxyl-terminal RIAs. Baseline PTH levels were lower in each patient when assessed by bioassay than when determined by RIA, and the rate of hormone disappearance was faster when determined by bioassay than when measured by RIA. This difference was accentuated in chronic renal failure due to prolongation of the disappearance rates of midregion and carboxyl-terminal immunoreactivity. The half-life of bioassayable hormone in patients with chronic renal failure was prolonged less than 2-fold compared to the half-life in patients with normal or restored renal function. The results emphasize the discordance between levels of bioactive and immunoreactive hormone regardless of renal function, demonstrate that this discordance is augmented after acute reduction in circulating hormone, and show that it is further increased when kidney function is impaired. The studies also implicate extrarenal mechanisms as a major factor in the clearance of bioactive hormone in established renal failure.
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PMID:Discordant disappearance of bioactive and immunoreactive parathyroid hormone after parathyroidectomy. 635 44

Over a period of six months all reports in the South Tees Health District of serum calcium levels greater than 2.70 mmol/l were extracted and patient records examined to establish the associated diseases and patterns of management. A total of 235 reports were evaluated, and after exclusion of doubtful cases 196 patients were included in the study. No cause had been identified in 57 (29%). Many of these were elderly females in whom hypercalcaemia may have been due to primary hyperparathyroidism, but parathyroid hormone levels had not been measured. Of those in whom a diagnosis had been made, 62 (45%) were associated with malignancy and 50 (36%) with chronic renal failure. 72% of cases of hypercalcaemia reported to general practitioners and 13% of those reported to hospital doctors were not investigated further. Despite the inclusion of serum calcium estimation on routine biochemical profiles, many cases of hypercalcaemia are being ignored or not investigated further. The study emphasizes the need for a reliable screening test for primary hyperparathyroidism.
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PMID:Hypercalcaemia in Cleveland: a hospital-based survey. 648 55

The effects of 1,25-dihydroxycholecalciferol (1,25-(OH)2D3) and 24,25-dihydroxycholecalciferol (24,25-(OH)2D3) on parathyroid hormone (PTH) release from human parathyroid cells were investigated using an in vitro system of dispersed cells. The cells were obtained from 7 patients with primary hyperparathyroidism (HPT) and adenoma, 4 patients with primary HPT due to hyperplasia and 2 patients with parathyroid hyperplasia secondary to chronic renal failure. The dispersed cells were incubated in tissue culture medium at low, normal and high external calcium concentrations for 2-16 h. There was a gradual suppression of PTH release (5-55%) when the calcium concentration in the medium was increased from 0.5 to 3.0 mM, thus indicating retained regulation of hormone release. The addition of 1,25-(OH)2D3 in concentrations of 0.1 and 1 ng/ml and of 24,25-(OH)2D3 in concentrations of 1.0 and 10 ng/ml during the incubations did not further affect the amount of PTH released by the cells. The concentrations of the different vitamin D metabolites tested closely correspond to levels observed under normal physiological conditions and during treatment with high doses of vitamin D in vivo. Thus, the findings contradict the idea of any direct short-term regulatory effect of either 1,25-(OH)2D3 or 24,25-(OH)2D3 on the secretion of PTH from hyperfunctioning human parathyroid tissue.
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PMID:Effects of 1,25- and 24,25-dihydroxycholecalciferol on parathyroid hormone release from human parathyroid cells in vitro. 660 1

In 46 patients with primary hyperparathyroidism, in 21 non-dialysed patients with advanced renal failure, and in 52 patients on hemodialysis, a significant positive correlation was found between bone isoenzyme of serum alkaline phosphatase and plasma tartrate resistant acid phosphatase. In primary hyperparathyroidism, a significant positive correlation was found between the radiological degree of osteodystrophy and the biochemical parameters of bone remodelling. After removal of the parathyroid adenoma, only the tartrate-resistant acid phosphatase decreased to normal limits. Plasma tartrate resistant acid phosphatase was most significantly influenced by serum immunoreactive parathyroid hormone levels. In chronic renal failure, bone isoenzyme of serum alkaline phosphatase was most significantly influenced by serum immunoreactive parathyroid hormone levels, by hypocalcemia and by duration of hemodialysis. The results confirm that in hyperparathyroidism the extent of the whole-body rates of bone resorption and formation are approximately equal. The biochemical parameters can be used for serial assessment of the course of the disease but are not specific for diagnosis.
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PMID:Relationship of plasma tartrate resistant acid phosphatase to the bone isoenzyme of serum alkaline phosphatase in hyperparathyroidism. 662 82

The excised parathyroid glands of twenty-one patients with secondary hyperparathyroidism due to chronic renal failure were submitted to careful histopathologic examinations including electron-microscopy. The previous history of these patients who had been on hemodialysis treatment for a certain period was relatively uniform with no association with primary hyperparathyroidism. Although eleven patients had four evenly enlarged parathyroid glands, eight patients showed four unevenly enlarged parathyroid glands with one or two glands weighing less than 100 mg. Histopathologic patterns of hyperplasia are easily divided into two distinctly different patterns, diffuse and nodular. Thirteen cases showed the same histopathological patterns of hyperplasia, either diffuse or nodular, in all excised glands. However, one or two out of four glands in eight patients evidenced a different histopathological pattern.
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PMID:Polymorphism of parathyroid glands in patients with chronic renal failure and secondary hyperparathyroidism. 667 53

The size of the parathyroid gland was evaluated at different functional levels of the gland (control: 216 glands in 54 autopsy cases, chronic renal failure: 74 glands in 21 autopsy cases, hypercalcemia: 16 glands in 15 patients with primary hyperparathyroidism). This study is based on the fact that chronic renal failure causes a hypersecretory state of parathyroid hormone (PTH), and that hypercalcemia suppresses PTH secretion. The size of the parathyroid gland was represented by the largest area cut through the hilum of the gland. Interstitial and fatty tissues were excluded from the measuring. The lower parathyroid glands are larger than the upper glands in the control. Both the upper and the lower glands enlarge with a predominance of the lower glands in size in chronic renal failure. These results suggest that the functional level of the lower glands is higher than that of the upper glands not only in the normal but in a hypersecretory state of PTH. Hypercalcemia has been shown to cause a decrease in size of the lower glands, while the upper glands scarcely decrease in size. This result indicates that the lower glands play a major role in reducing PTH secretion when PTH secretion is suppressed. It is concluded that the lower parathyroid glands play a more important role than the upper glands in the maintenance and regulation of PTH secretion.
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PMID:An evaluation of the size of the parathyroid glands. 674

Bone Gla protein (BGP) was measured in the plasma by radioimmunoassay (RIA) during treatment of 59 patients with bone diseases including Paget's disease (N = 9), primary hyperparathyroidism (N = 25), chronic renal failure (N = 20), and cancer involving bone (N = 5). Plasma BGP was increased above normal in all patients. BGP decreased in the patients with Paget's disease following the acute and chronic administration of salmon calcitonin. Plasma BGP was higher in women then in men with primary hyperparathyroidism. Following parathyroidectomy, BGP decreased in both sexes but the decrease was significant in women only. Plasma BGP was increased in patients with renal osteodystrophy and did not change after hemodialysis. In the patients with bone cancer, plasma BGP decreased during treatment of the attendant hypercalcemia with salmon calcitonin. Although plasma BGP and serum alkaline phosphatase (AP) levels were generally correlated in these studies, there were examples of dissociation between the two. The measurement of plasma BGP appears to provide a specific index of bone metabolism that may in some circumstances be more sensitive than serum alkaline phosphatase measurement. However, further studies are necessary to establish the clinical value of plasma BGP measurement by RIA in the management of patients with bone diseases.
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PMID:Changes in plasma bone GLA protein during treatment of bone disease. 680 17

The nuclear diameter of chief cells was measured in 17 cases of parathyroid adenomas, four cases of secondary hyperplasia, five cases of primary hyperplasia and six cases of tertiary hyperparathyroidism. All the cases with secondary hyperplasia and tertiary hyperparathyroidism were associated with chronic renal failure. The nuclear diameter in both the adenomatous and hyperplastic areas of tertiary hyperparathyroidism were measured. The adenomatous areas of tertiary hyperparathyroidism contained nuclei of a larger diameter than those in the hyperplastic foci of the same gland. The nuclear diameter in adenomatous foci of tertiary hyperparathyroidism was similar to that in adenomas from primary hyperparathyroidism. These findings lend support to the concept of formation of autonomous adenomas against a background of reactive parathyroid hyperplasia in cases of tertiary hyperparathyroidism. Using statistical methods there were differences between the nuclear diameter in cases of primary adenomata, and cases of primary and secondary hyperplasia. Primary parathyroid hyperplasia stood out as a distinct group. The significance of these findings is discussed.
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PMID:Nuclear diameter in parathyroid disease. 682 69

The autotransplantation of normal as well as adenomatous parathyroid tissue is currently being used with increasing frequency. In the present report, we describe our experiences with the successful transplantation of adenomatous or hyperplastic parathyroid tissue in seven patients. Prior to transplant surgery, six of these patients had recurrent or persistent primary hyperparathyroidism. The last patient was on hemodialysis for chronic renal failure and was presumed to have tertiary hyperparathyroidism. A large superior mediastinal parathyroid adenoma was found at a second neck exploration. In all patients, the only remaining parathyroid tissue was either adenomatous or hyperplastic. A total of 30 to 75 mg of this parathyroid tissue was diced and transplanted into single subfascial pockets of the forearm muscles (6) or sternocleidomastoid muscle (1). Following transplantation, all patients required transient calcium and vitamin D supplements for six to 12 weeks. In follow-up studies of ten months to 12 years, all patients have remained eucalcemic with normal parathyroid hormone levels. The use of a single subfascial pocket (versus the popular method of multiple implants) may explain the lack of recurrent hyperparathyroidism in our small population.
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PMID:Successful autotransplantation of parathyroid adenomas in seven patients. 685 73


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