Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020437 (hypercalcemia)
 10,293 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Biochemical signs and severity of symptoms of primary hyperparathyroidism (pHPT) differ among patients, and little is known of any coupling of clinical characteristics of nonfamilial pHPT to genetic abnormalities in the parathyroid tumors. Mutations in the recently identified MEN1 gene at chromosome 11q13 have been found in parathyroid tumors of nonfamilial pHPT. Using microsatellite analysis for loss of heterozygosity (LOH) at 11q13 and DNA sequencing of coding exons, the MEN1 gene was studied in 49 parathyroid lesions of patients with divergent symptoms, operative findings, histopathological diagnosis, and biochemical signs of nonfamilial pHPT. Allelic loss at 11q13 was detected in 13 tumors, and 6 of them demonstrated previously unrecognized somatic missense and frameshift deletion mutations of the MEN1 gene. Many of the detected mutations would most likely result in a nonfunctional menin protein, consistent with a tumor suppressor mechanism. Clinical and biochemical characteristics of HPT were apparently unrelated to the presence or absence of LOH and the MEN1 gene mutations. However, the demonstration of LOH at 11q13 and MEN1 gene mutations in small parathyroid adenomas of patients with slight hypercalcemia and normal serum PTH levels suggest that altered MEN1 gene function may also be important for the development of mild sporadic pHPT.
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PMID:Parathyroid MEN1 gene mutations in relation to clinical characteristics of nonfamilial primary hyperparathyroidism. 970 20

The two most common causes of hypercalcemia are malignancy and primary hyperparathyroidism (1 degree HPT). The radiographic presentations and the histological findings on bone biopsy are important for differential diagnosis of underlying diseases. We report a patient with hypercalcemia who presented unusual bone manifestations. A 43 y/o woman was admitted due to right femoral fracture. X-ray on the right tibia revealed several osteolytic cystic lesions with sclerotic rims. Blood biochemistry showed anemia, impaired renal function and hypercalcemia. Multiple osteolytic lesions on the skull and bilateral forearms were also noted. Malignancy, such as multiple myeloma or metastatic cancer was suspected. However, this was excluded because of the absence of M-component on serum protein electrophoresis and the negative finding of plasma cells or other malignant cell on bone biopsy examination. Abdominal sonography demonstrated bilateral medullary nephrocalcinosis. The final diagnosis of 1 degree HPT was made, based on the findings of classic pathological pictures (brown tumor) and the markedly elevated intact parathyroid hormone (1267.4 pg/ml) level. Sonography on the neck and 201Tl/99mTc parathyroid subtraction scan localized a left lower parathyroid tumor and fine needle aspiration confirmed the parathyroid origin. Diagnosis of 1 degree HPT could only be made from recurrent urolithiasis and X-ray picture of osteitis fibrosa cystica in the past. This patient presented the full-blown skeletal changes which are uncommonly seen nowadays. The characteristic sclerotic rims suggesting increased bone formation provides a further important clue for differential diagnosis of 1 degree HPT from other malignancies with osteolytic bone lesions.
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PMID:A patient of primary hyperparathyroidism with full-blown bone changes simulating malignancy. 979 3

In this double-blind, placebo-controlled, randomized, multicenter study, 35 patients with end-stage renal disease undergoing maintenance hemodialysis were treated three times weekly for 4 weeks with either 19-nor-1,25-dihydroxyvitamin D2 (paricalcitol) intravenously at doses ranging from 0.04 to 0.24 microg/kg or placebo. Eligible patients with secondary hyperparathyroidism (HPT; intact parathyroid hormone [iPTH] level > 300 pg/mL) were initially withdrawn from any existing vitamin D therapy over a 4-week washout period and then randomized to treatment for 4 weeks with either paricalcitol or placebo. Overall, there was a clinically and statistically significant reduction in iPTH level for patients receiving paricalcitol compared with placebo (P = 0.006). The study end point for efficacy was at least a 30% reduction from maximum baseline in iPTH level for 75% of the patients receiving paricalcitol per dosing group. The study end point for efficacy was at least a 30% reduction from maximum baseline in iPTH for 75% of patients receiving paricalcitol per dosing group. Sixty-eight percent (15 of 22) of patients receiving paricalcitol attained this efficacy end point regardless of dosage received (0.04, 0.08, 0.16, and 0.24 microg/kg). Eighty-three percent (5 of 6) of the patients in each of the paricalcitol groups receiving 0.16- and 0.24-microg/kg dosages attained the efficacy end point. Only two patients receiving placebo attained the iPTH end point. There were no clinically relevant differences in serum calcium (Ca) or phosphorus (P) levels between the group treated with paricalcitol and that treated with placebo. Although there was a statistically significant difference between the change from baseline to final-visit Ca levels in the paricalcitol group and the placebo group (P < 0.001), the final-visit mean Ca level in the paricalcitol group was within the normal range (9.44 mg/dL). There was no statistically significant difference between groups for the change from baseline in P level (P = 0.625). Only one patient treated with paricalcitol developed hypercalcemia before or coincident with the iPTH end point. Three other patients receiving paricalcitol experienced elevated serum Ca levels subsequent to reaching the iPTH end point, with iPTH reductions of 83% to 98%. There were no significant differences between patients treated with paricalcitol and patients treated with placebo in adverse reactions. These results show that paricalcitol safely and effectively reduces iPTH levels in hemodialysis patients with secondary HPT.
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PMID:Suppression of parathyroid hormone secretion in hemodialysis patients by a novel vitamin D analogue: 19-nor-1,25-dihydroxyvitamin D2. 980 43

Osteogenesis imperfecta (OI) and hyperparathyroidism (HTP) are disorders affecting the skeletal system and calcium metabolism not evidently related to one another. We report a case in which both OI and HPT were present. Our female patient presented with hypercalcaemia (S-Ca2+ 1.59 mmol/l; normal range 1.15-1.30) and 4-gland parathyroid hyperplasia at 30 years of age. Since her first year she had fractures, blue sclera, hypermobile joints, short stature (height 1.51 m, weight 49.5 kg) but normal hearing, and dentiogenesis imperfecta (tooth disease caused by defective formation of dentin) was absent. This patient bears many similarities with the 5 patients reported previously but it is the only patient, to our knowledge, with OI and early onset of HPT (30 year old female). We have found the OI to be type 1. A minor improvement of the rate of bone turnover 10 months after parathyroidectomy indicates the HPT to be primary and suggests the OI type 1 and pHPT to be two different calcium metabolic diseases incidentally occurring in the same patient.
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PMID:Co-existence of osteogenesis imperfecta and hyperparathyroidism. 1047 53

The primitive hyperparathyroidism (PHPT) constitutes still cause of discussion both from the diagnostic point of view and from the therapeutic one although surgical successes are generally reported. Between the most important problems there is the increase of the HPT asymptomatic or oligosymptomatic patients with the decisional difficulties in the timing of the surgical treatment and the difficult framing of the HLP disease associated with MEA and the relating surgical failures. Besides some authors support an unilateral dissection of the neck in patients with adenoma diseases diagnosed before the intervention against the traditional address of a bilateral exploration. Our experience is based on 31 patients subjected to intervention of parathyroidectomy for primitive HPT: 26 carriers of adenomas, of which 1 double, and 5 of diffused hyperplasia. We have effected 25 simple parathyroidectomy for adenoma, 1 resection of three parathyroid glands for double adenoma, 2 subtotal parathyroidectomy (7/8) for diffused hyperplasia. 2 patients had new surgical treatment for persistent hypercalcemia, and they were respectively carriers: 1 of a second ectopic adenoma and 1 of asymmetrical hyperplasia; 2 patients finally, operated in other hospitals had a second exploration and they were affected from MLP. In 26 patients we had very good results, in 2 persistence of hypercalcemia (patients who had a second look) and 3 hypocalcemia.
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PMID:[The surgical treatment of primary hyperparathyroidism: clinical experience]. 1080 73

The oral active vitamin D pulse therapy was performed for 20 chronic hemodialysis patients with secondary hyperparathyroidism (2 degrees HPT). Before pulse therapy, all patients showed high-turnover bone diseases, elevated serum alkaline phosphatase (Alp) and elevated serum parathyroid hormone (PTH). They had at least one parathyroid gland detected by ultrasonography. In one patient, serum PTH level did not decrease during three months. In five patients, hypercalcemia was observed so that the pulse therapy was with drawn. Another patient was resistant to the second pulse therapy for recurrence of 2 degrees HPT. Total parathyroidectomy and autotransplantation was performed in these seven patients. The size of parathyroid gland in patients undergoing surgical treatment was significantly larger than those estimated by ultrasonography in patients successfully treated with pulse therapy (p < 0.005). In all patients with surgical treatment, the conventional oral active vitamin D therapy was performed with caution to hypercalcemia preoperatively. The preoperative Alp levels decreased compared with those of at the beginning of the pulse therapy. Postoperatively, the total amount of intravenous administered calcium decreased, and serum calcium levels were easily controlled.
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PMID:[A clinical study on active vitamin D pulse therapy in hemodialysis patients with secondary hyperparathyroidism]. 1080 72

Thyroid imaging approach is based on the preliminary clinical evaluation. Lesions that are smaller than 2 cm should be assessed with US, which is capable of discriminating masses as small as 2 mm and distinguishing solid from cystic nodules. US-guided FNAB provides tissue for cytologic examination of thyroid nodules. CT and MR imaging are indicated for larger tumors (greater than 3 cm diameter) that extend outside the gland to adjoining structures, including the mediastinum, and retropharyngeal region. Metastatic lymph nodes in the neck and invasion of the aerodigestive tract are also in the realm of CT and MR imaging. Thyroid nodules are categorized on scintigraphy as hot or cold nodules. Hot nodules are rarely malignant, whereas cold nodules have an incidence of 10% to 20% of malignancy. Calcifications (amorphous, globular, nodular, and linear) occur in adenomas and carcinomas and have no differential diagnostic features except for psammomatous calcifications, which are a pathognomonic finding in papillary carcinomas and a small percentage of medullary carcinomas. Papillary carcinoma is the most common malignant tumor (80%) followed by follicular (20% to 25%); medullary (5%); undifferentiated; anaplastic carcinomas (< 5%); lymphoma (5%); and metastases. Lymph node metastases are common in papillary carcinoma, 50% at presentation, and less common in follicular carcinomas. The metastatic nodes in papillary carcinoma may enhance markedly (hypervascular); show increased signal intensity on T1-weighted images (increased thyroglobulin content or hemorrhage); and reveal punctate calcifications. Localized invasion of the larynx, trachea, and esophagus occurs predominantly in papillary and follicular carcinomas; the incidence is less than 5%. Ectopic thyroid tissue may be encountered in the tongue (foramen cecum); along the midline between posterior tongue and isthmus of thyroid gland; lateral neck; mediastinum; and oral cavity. Goiter and malignant tumors, notably papillary carcinoma, may develop in ectopic thyroid tissue. Carcinomas may also arise in thyroglossal duct cysts, which develop from duct remnants between the foramen cecum and thyroid isthmus. Infectious disease of the thyroid gland is not common and the CT and MR imaging findings are similar as described under neck infection. Other types of inflammatory disorders including Hashimoto's thyroiditis, granulomatous thyroiditis, and Riedel's struma display no specific imaging features. Imaging studies may, however, be indicated to confirm a suspected clinical diagnosis and assess compromise of the airway (Riedel's struma). HPT is a clinical diagnosis in which hypercalcemia is the most important finding. Parathyroid hyperplasia, adenoma, and carcinoma represent underlying lesions. To relieve the patient's symptoms surgical extirpation is indicated. The surgical success rate without imaging is 95%. The indications for imaging studies vary but it is generally agreed that reoperation after a previous failed surgical attempt and suspicion of an ectopic parathyroid adenoma should be investigated by imaging. These consist of US, nuclear medicine studies, CT and MR imaging. US and technetium sestamibi scanning have the highest accuracy rate for localizing an adenomatous gland at and near the thyroid gland. Ectopic adenomas, particularly if they are located in the mediastinum, are preferrably investigated with CT and MR imaging with gadolinium and fat suppression. Carcinomas and parathyroid cysts are optimally evaluated by CT and MR imaging. On MR imaging adenomas are low in signal intensity on T1-weighted images, high in signal intensity on T2-weighted images, and enhance post introduction of gadolinium.
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PMID:The thyroid and parathyroid glands. CT and MR imaging and correlation with pathology and clinical findings. 1105 72

There is currently no ideal long-term medical management for HPT. Estrogen remains an excellent option for selected postmenopausal women. Bisphosphonates provide skeletal protection even though hypercalcemia persists. Calcimimetic drugs appear to offer the best promise for future treatment. For patients who need stabilization as a prelude to surgery, intravenous pamidronate may be very useful. Even if effective long-term therapy is developed for HPT, it must be considered with respect to surgery, which, if successful, is relatively inexpensive and curative. Long-term medical follow-up requires close scrutiny on an indefinite basis. Components of such scrutiny will include periodic health history and physical examination, serum calcium and creatinine concentrations, creatinine clearance, 24 hour urinary calcium excretion, and BMD determinations [10]. If specific drug therapy is given, more frequent monitoring for adverse effects would probably the required.
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PMID:Diagnosis and treatment of hyperparathyroidism. 1170 38

Hypercalcemia and a relative nonsuppressibility of parathyroid hormone by calcium are the biochemical hallmarks of primary hyperparathyroidism. An elevated PTH level should be defined in a highly sensitive and specific test system. Primary HPT is the single major cause of hypercalcemia in outpatients. A definitive medical option to manage PHP does not exist. Surgical neck exploration by an experienced surgeon has a very high success rate for cure in both symptomatic and asymptomatic disease forms. Secondary HPT is mostly due to renal failure. Nonsuppressibility of PTH by use of vitamin D sterols indicates parathyroid gland hyperplasia and autonomy of PTH secretion. Surgery should correct PTH excess and should lead to an optimal bone status.
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PMID:[Clinical and biochemical diagnosis of pHPT and sHPT, surgical indications from the internal medicine viewpoint]. 1182 51

Mediastinal exploration to resect ectopic parathyroid is required in approximately 2% of all cases of hyperparathyroidism. Traditionally, it has been performed through a midsternotomy or thoracotomy. A few reports about thoracoscopic resection of mediastinal parathyroid were published recently. We report here successful video-assisted thoracoscopic resection (VATS) of a mediastinal parathyroid and present a review of all previously reported cases. A 42-year-old woman presented with spontaneous fracture of the left femur and hypercalcemia. She had previously undergone cervical parathyroidectomy for primary hyperparathyroidism. A computed tomography (CT) scan of the chest and a technetium scan showed ectopic mediastinal parathyroid. The patient underwent successful thoracoscopic resection of ectopic parathyroid. A total of 26 patients were reviewed, 21 in the English literature and 5 in others. Of the 21 patients reported in the English literature, 16 had primary hyperparathyroidism (1 degrees HPT), whereas 5 had secondary hyperparathyroidism (2 degrees HPT). All but 3 patients had undergone previous cervical exploration. Ectopic mediastinal parathyroid was localized preoperatively in all by CT scans of the chest and nuclear scans. All 21 patients had successful thoracoscopic resection. All but 3 had parathyroid adenoma. Postoperatively, serum calcium (Ca ), phosphate (PO4 ), and parathormone (PTH) values returned to normal in all patients. Age and sex of the patient, type of hyperparathyroidism (1 degrees or 2 degrees ), size of the gland, its location within the anterior mediastinum, the approach used to resect it (right or left thoracoscopic), and final histopathology of the resected gland (adenoma or hyperplasia) had no bearing on the success of thoracoscopic resection. The data seem to suggest that thoracoscopic resection of mediastinal parathyroid is a less-invasive, effective, and safe procedure. Accurate preoperative anatomic localization by CT and nuclear scans of the chest is the key to success.
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PMID:Thoracoscopy: the preferred method for excision of mediastinal parathyroids. 1219 31


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