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Query: UMLS:C0020437 (hypercalcemia)
 10,293 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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

Two women ahd acromegaly due to a pituitary adenoma associated with phaeochromocytoma. Eight additional patients with this combination of tumours have been described by others. Our first patient had sustained hypertension, mild hypercalcaemia, and elevated basal levels of parathyroid hormone and calcitonin associated with malignant phaeochromocytoma and parathyroid hyperplasia. The second patient had episodic hypertension and normal basal serum calcium, parathyroid hormone, and calcitonin levels with a benign cystic phaeochromocytoma. Four of the ten patients died from causes related to the phaeochromocytoma. Three patients had parathyroid hyperplasia. A separate group of four patients with phaeochromocytoma and pituitary adenoma without acromegaly has also been reported. These fourteen patients probably represent a non-familial variant of the multiple endocrine neoplasia syndrome. Our findings suggest that acromegalic patients with hypertension should be screened for phaeochromocytoma.
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PMID:Acromegaly and pituitary adenoma with phaeochromocytoma: a variant of multiple endocrine neoplasia. 729 6

Since 1973, we have performed total parathyroidectomy and forearm parathyroid autotransplantation in 36 patients with generalized (four gland) primary parathyroid hyperplasia. Twenty (56%) patients had nonfamilial parathyroid hyperplasia (NFPH) and 16 (44%) patients had familial parathyroid hyperplasia (FPH). Twenty-one patients (Group A) were undergoing operation for the first time and 15 (Group B) were having either second, third or fourth re-explorations for persistent hyperparathyroidism. All patients in Group A and nine patients in Group B had parathyroid resection and immediate autotransplantation as a single procedure. Six Group B patients had hyperfunctioning parathyroid tissue resected, cryopreserved, and subsequently grafted when it was evident that they had been rendered aparathyroid. A sustained differential elevation (13.7 fold +/- 2.7) of parathyroid hormone was detected in the antecubital vein of the grafted compared to the nongrafted arm in 35 (97%) patients. Two (5.6%) of the 36 patients (both with FPH; one Group A and one Group B) required permanent oral calcium and vitamin D replacement therapy and one (3%) patient (NFPH: Group A) had persistent hypercalcemia postoperatively, presumably due to a supernumerary gland. The remaining 33 (92%) patients became normocalcemia after surgery and 23 (70%) of them remained so. Ten (30%) of the 33 patients developed recurrent graft dependent hyperparathyroidism. Eight patients were from the group with FPH (8/14, 57%) and two were from the group with NFPH (2/19, 11%)(FPH vs. NFPH, p < 0.005). Because of symptoms of hypercalcemia or a serum calcium concentration exceeding 11 mg/dl, partial graft resection was performed in five patients and four became normocalcemic. Patients with generalized primary parathyroid hyperplasia may be difficult to cure, especially if the disease is familial. The technique of total parathyroidectomy and heterotopic autotransplantation of fresh or cryopreserved parathyroid tissue offers distinct advantages over alternative techniques.
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PMID:Long-term evaluation of patients with primary parathyroid hyperplasia managed by total parathyroidectomy and heterotopic autotransplantation. 742 91

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

Mice lacking the calcium-sensing receptor (Casr) were created to examine the receptor's role in calcium homeostasis and to elucidate the mechanism by which inherited human Casr gene defects cause diseases. Casr+/- mice, analogous to humans with familial hypocalciuric hypercalcemia, had benign and modest elevations of serum calcium, magnesium and parathyroid hormone levels as well as hypocalciuria. In contrast, Casr-/- mice, like humans with neonatal severe hyperparathyroidism, had markedly elevated serum calcium and parathyroid hormone levels, parathyroid hyperplasia, bone abnormalities, retarded growth and premature death. Our findings suggest that Casr mutations cause these human disorders by reducing the number of functional receptor molecules on the cell surface.
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PMID:A mouse model of human familial hypocalciuric hypercalcemia and neonatal severe hyperparathyroidism. 749 9

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

Secondary hyperparathyroidism is found in a large proportion, but not all patients on dialysis. Calcitriol controls moderate hyperparathyroidism in most patients but only in a proportion of those with advanced hyperparathyroidism. Patients with nodular parathyroid hyperplasia respond less frequently, presumably because of monoclonal growth and diminished calcitriol-receptor expression by parathyroid cells. In patients with nodular parathyroid hyperplasia, parathyroidectomy is an important alternative to calcitriol treatment. A priori reasoning indicates that prophylactic administration of calcitriol (to prevent parathyroid hyperplasia) is a reasonable option, but currently no controlled evidence for long-term efficacy of this approach without side effects is available. Intermittent administration of calcitriol by intravenous or oral routes is effective and, at least in experimental studies, superior to continuous calcitriol. However, in clinical comparisons, no superiority of intravenous versus oral or daily versus intermittent calcitriol has been documented. Calcitriol treatment must be closely supervised to prevent hypercalcemia, hyperphosphatemia, and excessive suppression of parathyroid hormone. Because of an altered dose response relationship, parathyroid hormone levels should not be completely normalized so as to prevent low bone turnover (adynamic bone lesion).
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PMID:Vitamin D therapy in patients receiving dialysis. 761 32

Four patients with familial hypophosphataemic rickets developed significant hypercalcaemia which persisted after discontinuation of vitamin D therapy. They had increased PTH levels and were operated for hyperparathyroidism at the ages of 18, 20, 24 and 45 years, respectively. Three of the patients had previously received phosphate treatment and one patient developed hyperparathyroidism 7 years after treatment with calcitriol. Histological evaluation revealed different degrees of parathyroid hyperplasia in all patients, with persistently increased PTH and/or calcium levels after surgery. The possibility of autonomous hyperparathyroidism should be evaluated in the follow-up of patients with X-linked hypophosphataemic rickets.
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PMID:Autonomous hyperparathyroidism in X-linked hypophosphataemia. 770 65

The clinical and laboratory data, and histologic, electron microscopic and immunocytochemical findings of a carcinoid tumor of the lung associated with parathyroid hyperplasia and persistent hypercalcemia are described. The carcinoid tumor consists of uniform cuboidal cells with regular round vesicular nuclei and eosinophilic granular cytoplasm. The tumor cells were chromogranin and neuron-specific enolase positive. The CAT scan of the abdomen revealed an adrenal mass, 3 cm in diameter, and an enlarged body in the pancreas. Our patient is still suffering from hypercalcemia and renal colic, despite repeated parathyroid gland removal, and enucleation of the lung mass. Recent parathyroid scintigraphy with Tc revealed an enlarged parathyroid gland. The thoracic CAT scan is normal. We believe that our patient is suffering from multiple endocrine neoplasia type-1 with persistent hypercalcemia due to hyperparathyroidism.
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PMID:Carcinoid tumor of the lung and type-1 multiple endocrine neoplasia associated with persistent hypercalcemia: a case report. 781 97

Generalized parathyroid hyperplasia with superimposed clonal tumor growth is the most frequent expression of the MEN 1 trait and must be corrected surgically. The Zollinger-Ellison syndrome is an indication for early and aggressive control of hypercalcemia. If gastrin secretion is normal, early parathyroid surgery is usually not required; and to delay the operation will facilitate location of all parathyroid glands, a requisite for successful surgery. The best surgical approach is an extensive primary dissection including thymectomy, followed by total parathyroidectomy with autogenous parathyroid grafting. Parathyroid disease in MEN 2 is less frequent and of later onset. It usually takes secondary consideration to the cure of the C-cell neoplasm. Several other less common hereditary syndromes with parathyroid involvement are reviewed.
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PMID:Management of hyperparathyroidism in the multiple endocrine neoplasia syndromes and other familial endocrinopathies. 791 26


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