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Query: UMLS:C0221002 (primary hyperparathyroidism)
 4,921 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Four patients with milk-alkali syndrome (MAS) presented with many of the characteristics of primary hyperparathyroidism including hypercalcemia, low or normal serum phosphorus levels, normal or increased urinary calcium levels, and inappropriately high or elevated serum parathyroid hormone levels. These laboratory findings differ from those classically described in MAS, i.e., hypercalcemia without hypercalciuria and a normal or high plasma phosphate level. Because the serum calcium level failed to return to normal after two weeks of hydration and a low calcium diet, and because of the inability to distinguish this syndrome from primary hyperparathyroidism, two of the four patients underwent neck exploration. Four normal parathyroid glands were histologically proven in each, and at autopsy in a third patient, there was no evidence of parathyroid hyperplasia or adenoma. Hypercalcemia eventually resolved in all patients with a low-calcium diet for as long as six months. Of the several features of MAS, hypercalcemia, alkalosis in the presence of azotemia, a history of increased calcium and alkali intake, and a response to dietary calcium restriction are helpful in differentiating this syndrome from primary hyperparathyroidism. Laboratory tests in patients with MAS may be confusing and the return to normocalcemia in response to a calcium deficient diet may be delayed.
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PMID:Milk alkali syndrome. Does it exist and can it be differentiated from primary hyperparathyroidism? 683 Mar 49

Eleven patients with clinical and biochemical evidence of primary hyperparathyroidism were studied with ultrasonography. In nine patients who were treated surgically, four had predictive ultrasound scans (44% consistency). There was no correlation between the transverse diameters of the glands, as measured from the scans, and either the pathologist's measurements or the mean protein-corrected serum calcium and parathormone (PTH) levels. The investigation failed to identify the only patient with parathyroid hyperplasia. The difficulties encountered and the reasons for the high number of both false positive and false negative scans are discussed. Five patients with parathyroid disorders associated with hyperplasia were also studied and in four patients the enlarged glands were identified. A variation in size between the glands in each patient was noted. No correlation between the total of the transverse diameters and either the protein-corrected serum calcium or PTH levels was found. Reduction in size of the glands in one patient occurred over a 12-month period on treatment and a role for ultrasonography in the follow-up of patients with secondary hyperparathyroidism is discussed.
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PMID:The use of ultrasound in the localisation of parathyroid glands in parathyroid disorders. 687 43

Of 2,058 patients who had surgically proven primary hyperparathyroidism at the Mayo Clinic from 1965 through 1979, 51 or 2.5 percent had associated nonmedullary thyroid carcinoma. A history of radiation exposure to the head and neck was obtained in 14 of 43 patients questioned. Thyroid disease consisted of grade 1 papillary adenocarcinoma in 48 cases and pure follicular adenocarcinoma in 3 cases. The parathyroid disease included 41 single adenomas and 5 cases of parathyroid hyperplasia; 5 patients had 2 adenomas. At follow-up, none of the patients had evidence of metastatic thyroid carcinoma. Ten patients were receiving calcium or vitamin D supplementation for protracted hypocalcemia presumably due to the increased insult to the parathyroids from combined bilateral thyroidectomy and parathyroidectomy. More consecutive thyroidectomy, along with parathyroid autotransplantation when indicated, will provide definitive treatment of the thyroid cancer and at the same time minimize the risk of postoperative hypoparathyroidism.
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PMID:Primary hyperparathyroidism and nonmedullary thyroid cancer. 706 49

Three hundred thirty-eight consecutive parathyroidectomies for hyperparathyroidism were performed over a 22 year period. There were 53 dialysis patients (31 male and 22 female), 285 patients (165 female and 120 male) with primary hyperparathyroidism, 55 patients (19 percent) with parathyroid hyperplasia, and 230 patients with 236 parathyroid adenomas. The location of the adenomas were right upper in 57, right lower in 59, left upper in 60, and left lower in 60. Forty-three patients of the last 194 operated on had histories of childhood head and neck irradiation (21.6 percent), 34 patients (79.6 percent) had associated thyroid disease, and there were 10 with thyroid carcinomas. In the 285 patients, 54 percent had thyroid disease, and 18 had thyroid carcinomas. Twenty-three patients required reoperation for persistent or recurrent hypercalcemia, and 19 neck reexplorations and 6 mediastinotomies were performed. The identification and biopsy as indicated of all four parathyroid glands at initial neck exploration would have prevented over 70 percent of reoperations.
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PMID:Parathyroidectomy. Review of 338 consecutive cases for histology, location, and reoperation. 712 71

Thirty-nine patients with primary hyperparathyroidism were studied four to eight years after their initial operation. In six patients, both the pathologist and surgeon agreed on the diagnosis of solitary adenoma; in 16 patients, the surgeon diagnosed solitary adenoma and the pathologist parathyroid hyperplasia (microscopic hyperplasia). In 16 patients, primary chief cell hyperplasia was agreed upon by the pathologist and surgeon. In the 16 patients with microscopic hyperplasia, there have been no long-term recurrences of hypercalcemia, but, in two patients, plasma parathyroid hormone levels are high. Parathyroid hormone--total calcium regression curves demonstrate significant preoperative correlation in solitary adenoma, p less than 0.01, and primary chief cell hyperplasia, p less than 0.05. After operation, significant correlations were not found between parathyroid hormone and total calcium. T-testing slope differences of pre- and postoperative parathyroid hormone--total calcium regression curves demonstrates a significant (p less than 0.01) shift to the right of the microscopic hyperplasia patients after operation, moving them to a broader range of total calcium per picogram parathyroid hormone. We conclude that 1) in primary hyperparathyroidism, positive regulation of total calcium by autonomously released parathyroid hormone exists in patients with solitary adenoma and chief cell hyperplasia; 2) autonomously functioning parathyroid tissue has been removed by operation for solitary adenoma with coexistent microscopic parathyroid hyperplasia. In this four- to eight-year follow-up period, it is clear that microscopic parathyroid hyperplasia is not associated with recurrent hypercalcemia. Two functionally distinct forms of parathyroid suppression are suggested; positively regulated microscopic hyperplasia and negatively regulated pathologically suppressed glands.
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PMID:Primary hyperparathyroidism: four- to eight-year postoperative follow-up demonstrating persistent functional insignificance of microscopic parathyroid hyperplasia and decreased autonomy of parathyroid hormone release. 728 4

The parathyroids from ten consecutive cases of chronic renal failure coming to operation in a period of seven years were studied by light and electron microscopy. The clinical and biochemical data as well as the levels of immunoreactive parathormone (iPTH) were reviewed. For the sake of comparison adenomata from two cases of primary hyperparathyroidism were studied. In the cases of chronic ;renal failure there were six cases of tertiary hyperparathyroidism with adenoma formation, surrounded by dense fibrous tissue and compression of adjacent parathyroid cell amidst a background of hyperplasia. Two cases showed secondary parathyroid hyperplasia and the remaining two cases were adenomata which clinically affected only one gland. Neither the biochemical data nor levels of iPTH allowed the cases with secondary hyperplasia to be separated from those with tertiary hyperparathyroidism. Similarly electron microscopy showed no distinct differences between these two groups of adenomata from cases of primary hyperparathyroidism. The diagnosis of tertiary hyperparathyroidism is made on a combination of clinical, biochemical and histological features, the histological features being most important. It is concluded that tertiary hyperparathyroidism is part of a histological spectrum in response to chronic renal failure and autonomous glands are related to the mass of parathyroid tissue present.
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PMID:The parathyroid in chronic renal failure-- a light and electron microscopical study. 744 5

Among 52 patients with recurrent renal calcium stones submitted for neck exploration 12 had adenomas, 23 hyperplasia and only 17 histologically normal parathyroid glands. These patients were selected for surgery despite a normal mean value of the total serum calcium concentration because they had, in most cases, indirect evidence of parathyroid hyperfunction such as intermittent hypercalcaemia (in 25 of the patients), hypercalciuria or a pathological response to calcium infusion. It is suggested that the patients with adenomas suffered from primary hyperparathyroidism (HPT), which however did not cause persisting hypercalcaemia. It seems likely that parathyroid hyperplasia either was a mild or an early form of primary HPT or secondary to increased calcium losses. In this study, no single laboratory feature could clearly separate the different groups. None of the patients with adenomas formed any new stone during follow-up (2-7 years) and also 40% of those with hyperplasia appeared to experience benefit from surgery. This benefit was more common in those with occasionally raised serum calcium values. In cases with borderline hypercalcaemia HPT is common and is cured by parathyroidectomy. However, in clinical practice the differential diagnosis may be difficult. In cases without firm evidence of HPT a conservative approach is favoured. Thiazides appear to reduce the stone recurrence rate in most euparathyroid patients and will probably help to unmask borderline HPT in recurrent renal stone formers.
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PMID:Clinical effects of parathyroid surgery in normocalcaemic patients with recurrent renal stones. 746 37

Following the third operation, aparathyroidism occurred in a 70-year-old female with primary hyperparathyroidism due to parathyroid hyperplasia. Part of the parathyroid obtained during the last operation was cryopreserved immediately after resection and replanted successfully after 15 days into the lower arm muscles. The function of the transplanted tissue was demonstrated by successful stepwise reduction of hormone substitution. Parathyroid hormone concentrations in the blood of the veins draining the transplanted tissue were more than double in comparison with the contralateral side. Functional and morphological investigations of the defrosted tissue prior to transplantation showed vitality and intact morphology.
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PMID:[Autotransplantation of cryopreserved human parathyroid tissue (author's transl)]. 747 68

Inactivating mutations of the parathyroid cell calcium receptor (CaR) gene cause one form of familial benign/hypocalciuric hypercalcemia, and in homozygous form, cause neonatal severe primary hyperparathyroidism with parathyroid hyperplasia. Thus, we postulated that partial or total loss of CaR function might contribute to calcium insensitivity or even stimulate cell proliferation in sporadic parathyroid adenomas (PAds). To examine this possibility, we sought loss of heterozygosity (LOH) for markers flanking the CaR locus (3cen-3q21) in 35 PAds. We used 16 highly-polymorphic PCR-based markers in paired normal and tumor DNA, extracted from slices of archived surgical specimens. Nineteen to 24 of the DNA pairs were informative with at least one marker. In two informative pairs, we found LOH for markers D3S1303, D3S1267, or D3S1269, which are tightly-linked with and flank the CaR locus. In one tumor, deletion mapping confined the lost area between D3S1271 and D3S1238 (41.7 centimorgans, cM). In the other tumor, LOH spanned most of chromosome 3, ranging at least from D3S1307 to D3S1311 (271.4 cM). LOH was confirmed by repetition of the experiments and quantified by phosphorimaging. Thus, we found LOH encompassing the CaR locus in approximately 10% of sporadic PAds. These data are consistent with the hypothesis that loss of CaR function may occur in PAds, with functional consequences for calcium sensitivity and cell proliferation.
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PMID:Genetic abnormalities in sporadic parathyroid adenomas: loss of heterozygosity for chromosome 3q markers flanking the calcium receptor locus. 759 8

Technetium99m (99mTc)-Sestamibi/123I subtraction scanning was prospectively performed in 30 patients with primary hyperparathyroidism in an attempt to locate enlarged glands before first surgery. Imaging results were compared to surgical findings; the surgeon tried to identify all parathyroid glands. Twenty-seven patients were found to have a solitary adenoma during surgery, and 3 had multiglandular parathyroid hyperplasia. Twenty-six parathyroid adenomas (96%) were accurately located before surgery. The smallest gland detected weighted 125 mg. Preoperative detection of two mediastinal adenomas allowed them to be excised by median sternotomy during the initial operation. 99mTc-Sestamibi/123I subtraction scanning predicted multiglandular involvement in two patients with parathyroid hyperplasia, whereas it showed a solitary image in the third. Ten patients (33%) had associated nodular thyroid disease, hindering image analysis and leading to one false positive result. 99mTc-Sestamibi scanning seems to be better for locating enlarged parathyroid glands than other noninvasive imaging techniques. However, 1) difficulties associated with thyroid nodules call for complementary thyroid scanning; and 2) images showing a solitary enlarged parathyroid gland do not rule out multiglandular disease. This technique should help in detecting lesions, such as mediastinal glands, that are difficult to find at initial surgery.
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PMID:Primary hyperparathyroidism: is technetium 99m-Sestamibi/iodine-123 subtraction scanning the best procedure to locate enlarged glands before surgery? 782 31


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