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

An increasing number of patients with primary hyperparathyroidism are found to have two or three enlarged parathyroid glands. Of 865 patients successfully operated on by one surgeon (J.N.A.), multiple enlarged parathyroid glands (adenomas) were found and resected in 33 cases (3.8%), with resulting normocalcemia lasting from 1 to 22 years (mean 5.8). Twenty-nine patients had two adenomas and four had three adenomas. In 28 patients the multiple adenomas were synchronous. Twenty-five patients underwent removal of all of the enlarged parathyroid glands in one operation; in three patients one adenoma was removed, reoperation for persistent hypercalcemia was performed, and a second adenoma was resected with cure. In five patients one adenoma was removed, normocalcemia ensued for 3 to 18 years, and a second (metachronous) adenoma occurred and was resected successfully. Although 10 of 70 enlarged parathyroid glands removed were labeled hyperplasia, cure in all but one of our patients by selective resection of only enlarged parathyroid glands emphasizes the unreliability of histologic criteria in differentiating between parathyroid adenoma and hyperplasia. Based on this study, we support the existence of multiple adenomas and advocate removal of only macroscopically enlarged parathyroid glands in patients with primary hyperparathyroidism.
Surgery 1990 Dec
PMID:Multiple parathyroid adenomas: report of thirty-three cases. 224 25

A preoperative transesophageal exploration of the parathyroids by endosonography was performed on 23 patients with primary hyperparathyroidism. The system used was a 7.5 MHz transducer mounted on the tip of an endoscope with an external diameter of 13 mm. The field of visualization was 360 degrees. A retrograde exploration was done moving up from the aortic arch to the upper esophageal sphincter. All patients underwent surgery afterward, and adenomas were found. In 12 cases the adenoma was visualized. All 12 adenomas were posteriorly located on the right side (four cases) and left side (eight cases) of the esophagus. Nine of these 12 tumors were on the posterior face of the thyroid lobes, with six tumors in the middle one third of the thyroid lobe and three in the lower one third of the thyroid lobe. The other three tumors were located below the lower pole of the thyroid lobes in the upper posterior mediastinum. Mean tumor weight was 1165 mg. Of the 11 tumors that could not be visualized, eight tumors were anteriorly located; three of these tumors were on the anterior and lateral surface of the lower pole of the thyroid, and five were in the thyrothymic tracts. The remaining three tumors were located on the back of the thyroid lobes; two of these tumors were at the upper esophageal sphincter, and one was on the side of the pharynx. Mean tumor size was 1334 mg. Localization of parathyroid tumors by endosonography appears possible but only if lesions are located posteriorly, close to the esophagus. Endosonography is not indicated before routine cervical exploration for primary or secondary hyperparathyroidism. As in other such studies, endosonography could be useful in cases of persistent or recurrent hyperparathyroidism.
Surgery 1990 Dec
PMID:Endosonography in the localization of parathyroid tumors: a preliminary study. 224 26

Heterotransplantation of adenomatous parathyroid glandular tissue from humans with primary hyperparathyroidism into athymic nude mice creates a unique animal model of this disease. The mice manifest high concentrations of both midregion/C-terminal human parathyroid hormone and biologically active intact human parathyroid hormone relative to either mice with no implants or mice that received normal human parathyroid tissue. Secretion of these substances is maintained in most mice for at least 9 to 13 months after implantation. In addition, animals that have experienced implantation exhibit other characteristics associated with human primary hyperparathyroidism including relative hypercalcemia and increased renal 25-hydroxyvitamin D-1 alpha-hydroxylase activity. We also measured these parameters in a group of nude mice that received transplantation of a similar mass of hyperplastic parathyroid tissue that was obtained from patients with uremic secondary hyperparathyroidism. Although we hypothesized that the level of human parathyroid hormone secretion from these implants would fall over time in response to the normal host environment, hormone levels remained as high as those in recipients of adenomatous heterografts, even after 9 to 13 months. Moreover, similar biologic effect of the excess parathyroid hormone (i.e., relative hypercalcemia, hyperphosphatasemia, and increased 1,25-dihydroxyvitamin D biosynthesis) were detected. These animal models should prove extremely useful in supplementing our understanding of hyperparathyroid disorder in man.
Surgery 1990 Dec
PMID:Function in athymic nude mice of parathyroid heterografts from patients with primary hyperparathyroidism and secondary hyperparathyroidism. 224 28

To explain the incidence and significance of mitral and aortic valve calcification and calcific deposits in the myocardium, a prospective echocardiographic study was performed with 21 consecutive patients who had primary hyperparathyroidism (PHP) and with 21 age- and sex-matched control subjects with normocalcemia. Calcific deposits in the myocardium were seen in 13 patients (62%) with PHP, mainly in the interventicular septum, and in one control subject. Aortic valve calcification was observed in 12 patients (57%) with PHP and in one control subject. Calcification of the mitral valve was found in seven patients with PHP (33%) and three controls (14%). Calcification led to mild or moderate stenosis of the aortic valve in three patients with PHP and of the mitral valve in two patients with PHP. No stenosis was found in the subjects in the control group. Both calcification of the aortic and mitral valves and calcific deposits in the myocardium are common in patients with PHP and can be detected noninvasively by echocardiography. Because of the potential relationship of elevated calcium, calcification, and valvular heart disease, clinical evaluation of PHP should include echocardiographic studies before surgery is performed and during follow-up examination.
Surgery 1990 Dec
PMID:Cardiac calcific deposits in patients with primary hyperparathyroidism: preliminary results of a prospective echocardiographic study. 224 30

The mechanism whereby PTH, a potent stimulator of bone resorption, may under certain circumstances exert anabolic effects on bone is not known, but it is possible that it involves reduction of the size of osteoclast resorption lacunae. We have therefore made a detailed in vitro study of the effects of PTH and PTH-related peptide (PTHrP) on resorption by neonatal rat osteoclasts paying particular attention to the plan area of resorption pits. In order to distinguish between increased resorption at a particular site and increased numbers of sites, we have used an eyepiece graticule to define a focus of resorption, namely an area occupying 1/116th of the bone slice, which may contain either one or several pits. In addition we have studied the relationship between the number of pits in a resorption focus and the total area of bone resorbed at the focus. We found that PTH and PTHrP, at doses between 2 x 10(-10) M and 2 x 10(-8) M, while exerting significant stimulatory effects on bone resorption, caused a reduction in the median plan area of pits. An increase in the number of resorption foci was the primary stimulatory effect of PTH and PTHrP, occurring within 6 h in the case of PTH. However, the plan area of bone resorbed at a focus showed no significant increase, despite an increase in the number of pits per focus, because as more pits were formed at a focus, the pits were smaller, thus partially dissipating the stimulatory effect of PTH on resorption. These results are consistent with the activation of new remodeling sites by PTH in vivo. Furthermore, the formation of smaller pits under the resorptive influence of PTH may, together with the maintenance of coupling between formation and resorption, play a role in the preservation of cancellous bone recorded in cases of primary hyperparathyroidism and the anabolic effect of exogenous PTH.
Endocrinology 1990 Dec
PMID:The effects of parathyroid hormone (PTH) and PTH-related peptide on osteoclast resorption of bone slices in vitro: an analysis of pit size and the resorption focus. 224 18

Osteocalcin, non-collagenous vitamin K dependent bone protein is as a biochemical indicator of osteoblastic activity and metabolic turnover in bone, valuable in the diagnosis of several diseases and in investigations of the dynamics of osseous changes (processes) during treatment of osteopathies. Elevated osteocalcin levels are normal in childhood and adolescence. In the diurnal rhythm the peak is recorded in the early hours. Pathologically elevated values are associated with primary hyperparathyroidism, Paget's disease, chronic renal failure, acromegaly and some malignities. A rise in women during the early postmenopausal period signalizes an enhanced metabolic turnover of bone in those women who are candidates of postmenopausal osteoporosis. Low levels are as a rule recorded in advanced age, in nanism, hypoparathyroidism, type 1 diabetes, rheumatoid arthritis, vitamin D deficiency, vitamin K deficiency, hypercorticalism and glucocorticoid treatment.
Cas Lek Cesk 1990 Dec 14
PMID:[Osteocalcin]. 227 72

To determine the incidence and causes of hypercalcaemia in a hospital population in Hong Kong, all 29,107 samples received in the laboratory in one year were analysed for plasma calcium and albumin, and samples with a plasma calcium concentration adjusted for albumin greater than 2.55 mmol/l were investigated. Plasma calcium greater than 2.55 mmol/l was found in 462 patients. Repeat samples were received from 302 of these and hypercalcaemia was confirmed in 183. The main causes of hypercalcaemia were malignancy (72.1 per cent), tuberculosis (6.0 per cent), and primary hyperparathyroidism (5.5 per cent). In the malignant hypercalcaemia group, carcinoma of lung was the most common (31.8 per cent) and carcinoma of breast was uncommon (3.0 per cent). Secondary deposits in bone were detected in 35 of the 122 solid tumours. In order to identify the mechanism of hypercalcaemia the contributions of renal tubular reabsorption and increased bone resorption to the plasma calcium concentration were calculated. Increased tubular reabsorption was the main contributor to hypercalcaemia in primary hyperparathyroidism and carcinoma of liver (none of whom had bony metastases) and it contributed significantly to hypercalcaemia in carcinoma of lung without bony metastases and carcinoma of oesophagus. We conclude that in Hong Kong (a) primary hyperparathyroidism is uncommon, (b) tuberculosis is an important cause and (c) humoral factors may be responsible for a relatively high proportion of cases of malignant hypercalcaemia.
Q J Med 1990 Dec
PMID:Incidence, causes and mechanism of hypercalcaemia in a hospital population in Hong Kong. 229 Sep 21

The study comprised 191 cases of surgically treated hyperparathyroidism, with all principal types of parathyroid disease represented. At least two complete glands stained with a modified isopropanol oil red O method for fat, in addition to sections stained with hematoxylin-eosin, were available in each case. On the basis of the morphologic evaluation and the clinical follow-up data, it is concluded that access to two complete glands and the use of fat staining allow highly reliable intraoperative distinction between adenoma and hyperplasia. Of 105 patients followed up for at least one year (mean, 20 months) in whom adenomas were diagnosed, a single possible error was identified. In each of 68 cases classified as hyperplasia on the basis of two abnormal glands, every additional complete gland available (total, 182 glands) was at least partially abnormal, with distinct signs of hyperactivity, irrespective of size. The rate of equivocal findings for cases in which two glands were available (probably adenoma but hyperplasia not excluded) was 8 per cent in 165 cases of primary hyperparathyroidism. These results justify limitation of surgery to one side of the neck in patients in whom adenoma is diagnosed on the basis of a complete, functionally normal (inactive) gland in addition to the presumed adenoma. Thus, the methods described provide a basis for optimal utilization of imaging techniques that allow preoperative localization of parathyroid adenomas.
Hum Pathol 1985 Dec
PMID:Fat staining in parathyroid disease--diagnostic value and impact on surgical strategy: clinicopathologic analysis of 191 cases. 241 41

The diagnosis of multiple endocrine neoplasia (MEN) in patients with presumed hyperparathyroidism has important ramifications for patient management especially since as many as 20% of patients with hyperparathyroidism may have associated MEN. Gut hormone levels were measured before and after surgery in 28 patients who underwent resection of a single parathyroid adenoma for biochemical or clinical evidence of hyperparathyroidism. The mean serum calcium level was 11.9 +/- 0.2 mg/dl before surgery and 9.3 +/- 0.3 mg/dl after surgery (p less than 0.001). Two or more hormone levels were elevated in 32% of patients before surgery and 21% after surgery. The same hormone abnormalities (pancreatic polypeptide [PP] and gastrin) occurred 56% of the time. Of elevated preoperative levels of PP, 91% were in the normal range after surgery. In patients with elevated preoperative PP levels, the postoperative level of PP decreased by an average of 64% of the preoperative level. In 27% of patients the level increased more than double the preoperative value. In two of four patients with high levels of PP after surgery the serum calcium level failed to fall. Of 18 patients whose PP levels fell, 17 had a fall in serum calcium levels. Of six patients whose PP levels rose, four had a significant fall in calcium levels. There was no correlation between the absolute levels or the decremental change of calcium and the change in PP. Several abnormalities in gut hormone secretion occur in patients with primary hyperparathyroidism and a parathyroid adenoma. An elevated serum level of PP does not signify MEN syndrome and must be reevaluated after resection of the parathyroid adenoma. Failure of adequate tumor resection is attended by persistent elevation of serum calcium and PP levels.
Surgery 1985 Dec
PMID:Hyperparathyroidism and gastroenteropancreatic hormone levels. 241 70

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.
J Clin Endocrinol Metab 1986 Dec
PMID:Parathyroid localization. 243 Sep 91


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