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

In patients with primary hyperparathyroidism, a definite diagnosis is the first step in the management strategy and relies on appropriately selected and carefully interpreted laboratory tests. Parathyroid hormone assays are being increasingly performed as part of the routine evaluation of osteoporosis. In this setting, laboratory tests are often consistent with primary hyperparathyroidism but should be interpreted with caution. Bone mineral density measurements are useful for assessing the impact of primary hyperparathyroidism. The recommended bone mineral density cutoffs for selecting patients requiring parathyroidectomy were lowered in 2003, and the number of surgically treated patients has increased as a result. Parathyroidectomy remains the treatment of choice given the low mortality associated with this procedure and the absence of pharmacological alternatives suitable for long-term use.
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PMID:Primary hyperparathyroidism and osteoporosis in 2004. 1518 88

The relationship between osteoporosis and primary hyperparathyroidism (pHPT) has not been definitely established because both diseases occur predominantly in postmenopausal women, and because PTH has a paradoxical effect on bone. We have investigated the prevalence of reduced bone mineral density (BMD) in women with pHPT, its relationship with metabolic parameters, and its course after parathyroidectomy. A prospective observational study was carried out on perimenopausal and postmenopausal women consecutively diagnosed and operated on for pHPT. Demographic data were recorded, as well as, PTH, Ca, calciuria/24h, P, vitamin D, adenoma weight. The BMD was measured at three sites: femoral neck (FN), proximal femur (PF), and lumbar spine (LS). Fifty-two patients were included with a mean age of 61+/-12 years. The prevalence of reduced BMD (< or = 1SD, T-score) was 80%-100% depending on site. Parathyroid hormone was higher in patients with osteoporosis (319+/-181 pg/ml) than in those with osteopenia (230+/-83 pg/ml) or normal BMD (148+/-81 pg/ml;p < 0,04). Twenty-eight patients were investigated 1 year after parathyroidectomy. The BMD improved significantly at all sites, particularly in patients with osteoporosis. Age correlated inversely with BMD increases at the femoral sites (r= -0,47;p = 0,02) but not at the LS. 25-OHD3 plasma levels correlated inversely with BMD increases at PF (r= -0,76; p < 0,0001). In pHPT, there is a high prevalence of BMD abnormalities. No metabolic variables had a definite influence on BMD values but a tendency was observed for lower BMD in severe pHPT. One year after parathyroidectomy, there were significant BMD increases that were more marked at femoral sites, in younger patients, in patients with preoperative osteoporosis, and in those with lower plasma levels of 25-OHD3.
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PMID:Bone mineral density in menopausal women with primary hyperparathyroidism before and after parathyroidectomy. 1549 63

Parathyroid hormone (PTH) promotes IL-6 secretion by osteoblasts, and may also up-regulate IL-6 production in the liver and adipose tissue; this may explain why serum IL-6 is markedly elevated in primary hyperparathyroidism, and low in hypoparathyroidism. IL-6 is the chief stimulus to hepatic production of many acute phase reactants, notably fibrinogen and C-reactive protein (CRP). Mild secondary hyperparathyroidism is common in elderly people, particularly at high latitudes during the winter, owing to poor vitamin D status. This may rationalize evidence that acute phase proteins show seasonal variations and are typically elevated in the elderly, whereas leisure physical activity is associated with a reduction in these proteins. In a recent clinical trial targeting elderly chronically ill patients, administration of vitamin D reduced serum levels of both CRP and IL-6; further such studies should assess the impact of physiologically meaningful doses of vitamin D on acute phase reactants in elderly subjects likely to have poor vitamin D status. Since elevations of CRP and fibrinogen may increase risk for thromboembolic vascular events, these considerations may help to explain the excess of coronary mortality observed during winter months, and suggest a role for supplemental vitamin D in preservation of vascular health. Moderate alcohol intake is associated with reduced serum PTH as well as decreased levels of CRP and fibrinogen; conceivably, modulation of PTH mediates, at least in part, the favorable impact of moderate drinking on the acute phase reactants.
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PMID:Secondary hyperparathyroidism promotes the acute phase response -- a rationale for supplemental vitamin D in prevention of vascular events in the elderly. 1578 May 4

Parathyroid hormone acts directly on bone by stimulating both bone resorption and bone formation with the relative excess in the former when it acts continuously. Thus in primary hyperparathyroidism characterized by chronic PTH excess, bone mineral density (BMD) is decreased with relatively high levels of bone turnover markers. In contrast, PTH deficient hypoparathyroidism such as post-operative hypoparathyroidism, BMD is increased with relatively low bone tunover markers. In pseudohypoparathyroidism, which characterized by PTH resistance in kidney, bone response to PTH is sometimes preserved. In some cases, high bone turnover state is observed, which correlates with serum PTH levels.
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PMID:[Parathyroid disorders and bone metabolism]. 1632 76

Parathyroid hormone (PTH) is the most important hormone to maintain serum calcium levels. PTH acts directly on bone by stimulating both bone resorption and bone formation with the reactive excess in the former when it acts continuously. PTH also acts on renal tubule to promote urinary excretion of phosphate as well as production active vitamin D (1,25 [OH] 2D) . 1,25 [OH] 2D has been also suggested to have some unique and direct action on the bone. Measurement of intact-PTH is essential for optimal management of bone abnormalities in patients with primary hyperparathyroidism, secondary hyperparathyroidism, and chronic kidney disease. The newer PTH assays ; whole-PTH and bio-intact PTH assay, use an antibody that binds the region including the first amino acid is present, making it specific for the complete molecule, (1-84)-PTH. Recently, a new molecular form of PTH has been reported, which cannot be detected by these newer PTH assays.
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PMID:[Bone and bone related biochemical examinations. Hormone and hormone related substances. Parathyroid hormone]. 1675 87

Parathyroid hormone (PTH) is secreted by parathyroid glands and is the main known factor that control plasma calcium concentration. There are many indications that PTH or products of PTH degradation influence the mean arterial blood pressure (MAP). These observations might be important in diseases accompanied with the overproduction of PTH such as primary hyperparathyroidism (PHPT). It was shown that the six amino acids PTH precursor-PRO-PTH with reversed sequence (PRO-rs), which contains a rare tripeptide -Arg-Lys-Lys- fragment, induces significant hypertensive response in rats. This strong alkali tripeptide is also present in the position 25-27 of the PTH molecule. The aim of the present study was to synthesize, by the solid phase peptide synthesis method, PTH fragments including the -Arg-Lys-Lys- sequence and test their influence on blood pressure and calcium plasma concentration in rats. Our study demonstrated that PTH(25-34) and the acetylated amide analogue of PTH(25-30), (Ac-PTH(25-30)-NH(2)) were hypertensive in the physiological doses. The presence of strong alkali sequence -Arg-Lys-Lys- in PTH(25-30) fragment is not sufficient to induce hypertension either in physiological or pharmacological doses in rats. Therefore, both the proximity of the -Arg-Lys-Lys- sequence and length of the peptide might also play roles as pressure factors.
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PMID:Hypertensive activity of synthesized PTH(25-34) and Ac-PTH(25-30)-NH2 in rats. 1901 89

Raw Cystic parathyroid adenoma is a rare cause of primary hyperparathyroidism. The authors report one case of cystic parathyroid adenoma, who presented with progressive right hip pain for one year. The patient had severe hypercalcemia at the first presentation and was misdiagnosed as having metastatic cancer at first. An iliac bone biopsy was performed and showed a giant cell tumor. Parathyroid hormone level was evaluated later and was found to be high, 1,555 pg/ml (15-65 pg/ml). An MRI study of the neck was done and revealed a cystic mass 38 x 36 x 40 mm in diameter just below the left lower pole of the thyroid gland. Tc-99m MIBI scan demonstrated increase and retention of radioactivity uptake at the same area. Hyperfunctioning parathyroid gland was considered. Parathyroidectomy was done and histopathology revealed cystic parathyroid adenoma. Serum calcium was normal and hip pain was markedly improved after the surgery.
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PMID:Primary hyperparathyroidism due to cystic parathyroid adenoma: a case report. 1923 Apr 28

This study was designed to assess the utility of fine-needle aspiration cytology (FNAC) in the preoperative localization of parathyroid adenoma (PA). Fifty-seven samples from fifty-three cases of PA (four patients had bilateral disease) were obtained by ultrasound (US)-guided fine-needle aspiration. Parathyroid hormone (PTH) estimation was performed on the supernatant of the aspirated fluid on all cases. Subsequently, all of them underwent cytologic evaluation. The cytology slides were evaluated using the following criteria: Cellularity, architectural patterns, bare nuclei in the background, nuclear morphology, and background features (colloid-like material or macrophages). Parathyroid cells were seen in 23 samples (40.4%). The cellularity of the smears was insufficient for interpretation in 16 samples (28.1%); and thyroid follicles and colloid were seen in 18 samples (31.5%). Majority of the samples with parathyroid cells showed moderate cellularity with monomorphous round to slightly oval cells predominantly arranged in loose two-dimensional clusters with occasional papillary fragments. Majority of them exhibited a stippled nuclear chromatin. No significant pleomorphism, mitotic activity, or prominent nucleoli were observed. Most samples showed bare nuclei in the background. In conclusion, US-guided FNAC has its limitations because of low sensitivity in primary localization of the parathyroid adenoma in cases of primary hyperparathyroidism and is not a useful mode of investigation in cases of PA.
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PMID:Parathyroid fine-needle aspiration cytology in the evaluation of parathyroid adenoma: cytologic findings from 53 patients. 1928 90

Primary hyperparathyroidism and malignancy are responsible for greater than 90% of all cases of hypercalcemia. Compared with the hypercalcemia of malignancy, hyperparathyroidism tends to be associated with lower serum calcium levels (< 12 mg/dL) and a longer duration of hypercalcemia (more than 6 months). The hypercalcemic symptoms are usually fewer and subtle. Hyperparathyroidism tends to cause kidney calculi, hyperchloremic metabolic acidosis, and the characteristics of metabolic bone disease osteitis fibrosa cystica, but no anemia. In contrast, hypercalcemia of malignancy is typically rapid in onset, with higher serum calcium levels, and more severe symptoms. Patients so affected show marked anemia, but they never have kidney calculi or metabolic acidosis. Parathyroid hormone assay is the most useful test for differentiating hyperparathyroidism from malignancy and other causes of hypercalcemia. In hyperparathyroidism, serum parathyroid hormone levels will be elevated. In other cases, the high serum calcium concentration usually results in suppression of parathyroid hormone. Treatment of hypercalcemia should be started with hydration. Loop diuretics may be required in individuals with renal insufficiency or heart failure to prevent fluid overload. Calcitonin is administered for the immediate short-term management of severe symptomatic hypercalcemia. For long-term control of severe or symptomatic hypercalcemia, the addition of biphosphonate is typically required. Among intravenous bisphosphonates, zoledronic acid or pamidronate are the agents of choice. Glucocorticoids are effective in hypercalcemia due to lymphoma or granulomatous diseases. Dialysis is generally reserved for those with severe hypercalcemia complicated with kidney failure.
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PMID:Hypercalcemia: an evidence-based approach to clinical cases. 1939 81

Primary hyperparathyroidism is a relatively common problem encountered in clinical endocrine practice. In most cases the diagnosis is relatively straightforward, however, when imaging studies fail to localize the parathyroid adenoma or hyperplasia, management can be challenging. We describe here such a case where the diagnosis was made by a novel method of analysis of parathyroid hormone levels in the needle wash obtained during fine-needle aspiration of a suspected parathyroid adenoma. A 60 year old white male was first seen in the endocrinology clinic for evaluation of osteoporosis. He had history of multiple compression vertebral fractures involving thoracic and lumbar vertebrae and fracture of right femoral neck following minimal trauma. He had high normal serum calcium and elevated urinary calcium levels. His parathyroid hormone level was within normal limits. Work-up for secondary causes of osteoporosis was unremarkable. He was started on hydrochlorthiazide therapy for a presumptive diagnosis of idiopathic hypercalciuria. Subsequently his serum calcium level became elevated and he continued to have significant hypercalciuria. The elevation in serum calcium persisted despite cessation of hydrochlorthiazide therapy. Parathyroid hormone level remained in mid-normal range. A diagnosis of primary hyperparathyroidism was considered at this stage and imaging studies were carried out to localize the parathyroid pathology. Parathyroid-sestamibi scan did not reveal any abnormality. Ultrasound examination of the neck showed a hypoechoic nodule posterior to right thyroid lobe. A fine needle aspiration of the nodule was carried out with estimation of parathyroid hormone level in the needle wash to indicate the presence of parathyroid adenoma. This was surgically removed later successfully with subsequent normalization of serum and urinary calcium levels. The current management of hyperparathyroidism is primarily surgical. Minimally invasive parathyroid surgery is the treatment of choice but it requires the clear localization of a parathyroid lesion for successful removal. In cases where preoperative localization is evasive, novel techniques, such as the one described above, can provide useful diagnostic information which can aid in the successful management of hyperparathyroidism. Further studies are needed before this technique can be applied on a more widespread basis.
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PMID:Parathyroid FNA and hormone assay. 1980 69


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