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

The association between primary hyperparathyroidism and nonmedullary thyroid malignancies is well known. There is also, however, some evidence for an association between secondary hyperparathyroidism (SHPT) and thyroid cancer. We report three patients in whom invasive papillary thyroid carcinoma (PTC) was diagnosed before (one case) or at the time of (two cases) parathyroidectomy for SHPT. Three women (ages 23, 54, and 64 years) presented with bone pain and pruritus typical of SHPT. All three patients had biopsy-proven parathyroid bone disease and elevated parathormone levels (664, 1674, and 2051 pg/mL). All underwent subtotal parathyroidectomy and total thyroidectomy without complications. Pathology revealed diffuse parathyroid hyperplasia with multifocal invasive papillary thyroid carcinoma (two cases) and follicular variant of papillary thyroid carcinoma (one case). Two cases were associated with metastatic disease to local lymph nodes. The patients received adjuvant radioactive 131I, and remained tumor free 24 to 36 months after surgery with complete resolution of SHPT. We conclude: 1) PTC may accompany SHPT, 2) PTCs associated with SHPT may be locally aggressive although usually they are early tumors, 3) surgeons need to have an index of suspicion for thyroid tumor when operating on patients with SHPT, and 4) routine removal of the thymus as part of the operation for SHPT may have a secondary benefit in diagnosing PTC in the occasional patient.
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PMID:Secondary hyperparathyroidism: evidence for an association with papillary thyroid cancer. 1137 34

We retrospectively evaluated the cases of 55 patients who had undergone surgery for primary hyperparathyroidism at our institution to determine whether their parathyroid glands were abnormal on both sides. Thirty-six of these patients had undergone a bilateral neck exploration, and 19 had had a unilateral investigation. Of the 36 bilaterally explored patients, 30 had a solitary adenoma and no parathyroid pathology on the opposite side, five patients had hyperplastic glands with more than one gland involved, and one patient had two adenomas. In the unilaterally explored group, all 19 patients had a solitary adenoma. There were no failures in the way of persistent hypercalcemia in either group. Based on our findings, we conclude that a unilateral neck exploration should be performed during surgery for primary hyperparathyroidism whenever a large parathyroid adenoma and a normal parathyroid gland are found on the same side. Bilateral exploration should be reserved for patients in whom pathology cannot be found on the initially explored side during surgery and for patients who have obvious parathyroid hyperplasia.
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PMID:Unilateral versus bilateral neck exploration in parathyroid surgery: an assessment of 55 cases. 1152 70

While intraoperative parathormone measurements are mandatory for unilateral operations of primary hyperparathyroidism (pHPT), its value for treatment of parathyroid hyperplasia is regarded as insufficient. We report a case of a pHPT with hyperplasia of five glands, in which only the intraoperative analysis of parathormone detected the remaining fifth hyperparathyroid gland after extirpation of four enlarged parathyroid glands. We describe technical problems involved in the tests available today and how the results of the intraoperative parathormone test need to be interpreted. As several factors can influence the decrease in parathormone concentration, a kinetic analysis may be more accurate in assessing the adequacy of resection. Therefore, intraoperative parathormone measurements are especially useful and important for adequate surgical therapy for pHPT with parathyroid hyperplasia.
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PMID:[Importance of intraoperative parathormone measurements in primary hyperparathyroidism with 5-gland hyperplasia]. 1171 22

Neonatal primary hyperparathyroidism is a rare entity characterized by marked hypercalcemia, diffuse parathyroid hyperplasia, and skeletal demineralization. It is often lethal unless total parathyroidectomy is performed. Long-term outcome of treated patients is poorly documented. We report the clinical and radiographic outcome of this disease in a 7-year-old boy who underwent a total parathyroidectomy and autotransplantation of a fragment of one parathyroid gland to his thigh in the neonatal period. This paper demonstrates the importance of prompt diagnosis and management in neonatal hyperparathyroidism and the role of various imaging modalities in its diagnosis and follow-up.
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PMID:Neonatal, severe primary hyperparathyroidism: a 7-year clinical and radiological follow-up of one patient. 1219 11

The response of parathyroid cells to serum calcium is regulated by a calcium-sensing receptor protein (CaR). In patients with chronic renal failure, hypocalcemia contributes to the parathyroid hyperplasia and increased parathyroid hormone secretion characteristic of secondary hyperparathyroidism (sHPT). However, patients with uremia also display reduced sensitivity to extracellular calcium; this seems to be owing to an alteration of the receptor mechanism. This study examined calcium receptor expression in the parathyroid tissue of patients with sHPT, using immunohistochemical techniques and comparison with normal tissue and parathyroid glands of patients with primary hyperparathyroidism. In all the glands studied, immunostaining was more intense in chief cells than in oxyphilic, transitional, and clear cells. The parathyroid glands of patients with sHPT displayed significantly reduced expression of CaR with respect to morphologically normal ones; a very similar reduction is reported in adenomas. Furthermore, in glands displaying multinodular hyperplasia, expression was less marked in nodule-forming cells than in internodular areas. The decreased expression of calcium receptors in the parathyroid tissue of uremic patients was thought to be owing to the different cell populations present; these parathyroid glands contained predominantly transitional, oxyphilic, and clear cells, which normally express fewer receptors than chief cells, which are more abundant in normal glands.
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PMID:Decreased expression of calcium receptor in parathyroid tissue in patients with hyperparathyroidism secondary to chronic renal failure. 1274 64

The simultaneous occurrence of hyperthyroidism and primary hyperparathyroidism is quite rare. A case is reported here of Graves' disease and primary hyperparathyroidism. Treatment of these concomitant diseases consists in combined thyroidectomy and parathyroidectomy. Histological examination confirmed Graves' disease and revealed the presence of a parathyroid adenoma in one gland and parathyroid hyperplasia in another one. After surgical treatment, secondary hyperparathyroidism due to 25-OH Vitamin D deficiency appeared. To our knowledge, this is the first case in which a Vitamin D absorption deficit was found in presence of hyperthyroidism and hyperparathyroidism without other intestinal absorption deficits. Diagnostic and follow-up difficulties related to these three concomitant pathological conditions are discussed.
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PMID:Concomitant primary hyperparathyroidism, Graves' disease and vitamin D deficiency. 1467 15

We report a multiple endocrine neoplasia type 1 (MEN1) patient associated with carcinoid syndrome. A 50-year-old woman had parathyroid hyperplasia with primary hyperparathyroidism, a pancreatic tumor and carcinoid tumors in the liver and duodenum. The primary lesion of the carcinoid was probably the bronchus. Direct sequencing analysis revealed a novel missense mutation at codon 342 in exon 7 causing an amino acid change from alanine to proline (A342P) of the MEN1 gene. Loss of heterozygosity (LOH) was also detected in the resected parathyroid tissue. This mutation appeared to play an important role in the tumorigenesis of the endocrine tissues in the present case.
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PMID:A novel missense mutation of the MEN1 gene in a multiple endocrine neoplasia type 1 patient associated with carcinoid syndrome. 1468 52

Primary hyperparathyroidism is a life-threatening rare disorder. It is seen as a result of neonatal primary hyperparathyroidism, familial hypocalciuric hypercalcemia, increased vitamin D levels and inactivation of calcium sensing receptor mutations. The clinical findings are hypotonia, bone demineralization, hypercalcemia and parathyroid hyperplasia. We present a six-month-old female patient, the first child of nonconsanguineous parents, who was referred for the investigation of failure to thrive, vomiting, constipation, fever, abdominal distention and hypotonia. Physical examination revealed weight under 3rd percentile, height 3rd-10th percentile, decreased subcutaneous fat, and distention of the abdomen. In neurological examination, hypotonia, motor-mental retardation, and active deep tendon reflexes were found. The biochemical values at the time of admission revealed primary hyperparathyroidism. Since hypercalcemia did not respond to calcitonin therapy and due to the mortality of hypercalcemia, parathyroidectomy was performed. Because hyperparathyroidism and hypercalcemia continued, angiography was done which revealed increased parathyroid hormone levels in the periphery of the innominate vein. Exploratory surgery followed, but hyperparathyroidism and hypercalcemia persisted after all of these procedures. Calcium-sensing receptor mutations and supernumerary gland were considered. Because hypercalcemia persisted, pamidronate therapy was initiated on a monthly basis.
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PMID:Persistent elevated serum levels of intact parathyroid hormone after reoperation for primary hyperparathyroidism and after pamidronate therapy. 1469 11

According to earlier reports, a decrease below 50% of baseline of intraoperative PTH levels measured 5 min after resection of the parathyroid adenoma predicts a cure of hyperparathyroidism. To reveal previously unrecognized pitfalls of intraoperative PTH measurements, we reviewed surgical failures in our series of parathyroidectomies combined with intraoperative PTH sampling. PTH measurements were performed in 251 patients with primary hyperparathyroidism (PHPT) between November 1999 and December 2002. PHPT due to parathyroid hyperplasia were found in 8 cases, double parathyroid adenomas in 6 cases, parathyroid carcinoma in 1 case and single parathyroid adenomas in 236 cases, all confirmed by histological examination. Of the 236 cases of single adenomas, initial surgery failed to cure PHPT in 4 patients. In 3 patients a false-positive decrease of intraoperative PTH (from 269 to 40 pg/ml, from 211 to 27 pg/ml, and from 140 to 59 pg/ml) was observed, whereas in the fourth patient a true-negative decrease of intraoperative PTH (from 758 to 401 pg/ml) was mistakenly interpreted as indication for a cure of PHPT. In each of the 4 patients in whom initial surgery failed the intervention included thyroid surgery and reoperative parathyroid surgery resulted in a permanent cure of PHPT. These observations support the possibility that thyroid surgery may compromise the blood supply of parathyroid adenomas resulting in a misleading drop of intraoperative PTH levels. Therefore, a careful evaluation of intraoperative PTH levels and, perhaps, other intraoperative aids such as histological evaluation of frozen sections are recommended when parathyroid surgery is combined with simultaneous thyroid intervention.
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PMID:Parathyroid surgical failures with misleading falls of intraoperative parathyroid hormone levels. 1500 47

Multiple endocrine neoplasia type 2 (MEN-2) is a hereditary syndrome that is transmitted in an autosomal dominant pattern. MEN-2A, MEN-2B, and familial medullary thyroid cancer (MTC) comprise the MEN-2 syndrome. A germline mutation in the RET proto-oncogene is responsible for the MEN-2 syndrome. Recent data indicate that in 99% of MEN-2 cases, a germline RET mutation can be identified by genetic testing. The phenotypic variation of MEN-2 is diverse and partly related to the codon and specific point mutation in the RET proto-oncogene. There are increasing data on the genotype-phenotype correlations in patients with MEN-2 and this information should be used for screening at-risk patients and treatment of RET mutation carriers. All patients (especially if young) with MTC or bilateral pheochromocytoma should have a careful family history taken and genetic screening for RET germline mutations. Patients who are RET germline mutation carriers but without clinical or biochemical evidence of MTC should have a prophylactic total thyroidectomy. The optimal age of thyroidectomy should be based on the RET genotype (eg, high-risk mutations within the first year of life, intermediate-risk mutations by 5 years of age, and low-risk mutations by 10 years of age). Patients who are diagnosed with clinical or biochemical evidence of MTC should have a total or a near total thyroidectomy and at least a central neck lymph node dissection. Patients who have pheochromocytoma and a unilateral adrenal tumor on a localizing study should have a unilateral laparoscopic adrenalectomy after preoperative alpha-blockade. However, patients with bilateral adrenal tumors on localizing studies should have bilateral laparoscopic adrenalectomy. A cortical-sparing (subtotal) adrenalectomy may be considered, if technically feasible, to avoid long-term steroid dependence and to reduce the risk of Addisonian crisis. Patients with biochemical evidence of primary hyperparathyroidism should have a bilateral neck exploration and total parathyroidectomy and autotransplantation (30-60 mg of the most normal parathyroid tissue) to the nondominant forearm if asymmetric parathyroid hyperplasia is present. Rarely, patients may have only single-gland disease and excision may be performed if the other parathyroid glands are not found with biopsy to be hyperplastic. All unresected parathyroid glands should be marked with a clip because patients with MEN-2A have a high risk of persistent and recurrent primary hyperparathyroidism. Patients with familial MTC may have not manifested the other features of MEN-2A, thus these patients should have continued follow-up for pheochromocytoma and primary hyperparathyroidism.
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PMID:Multiple endocrine neoplasia type 2. 1523 8


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