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Serum PTH (serum + pth)
Selected AbstractsHeterogeneity in Serum 25-Hydroxy-Vitamin D Response to Cholecalciferol in Elderly Women with Secondary Hyperparathyroidism and Vitamin D DeficiencyJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 8 2010Andrea Giusti MD OBJECTIVES: To compare the effects on parathyroid hormone (PTH) and 25-hydroxy-vitamin D (25(OH)D) of two dosing regimens of cholecalciferol in women with secondary hyperparathyroidism (sHPTH) and hypovitaminosis D and to investigate variables affecting 25(OH)D response to cholecalciferol. DESIGN: Randomized-controlled trial with 6-month follow-up. SETTING: Two osteoporosis centers in northern Italy. PARTICIPANTS: Sixty community-dwelling women aged 65 and older with sHPTH and hypovitaminosis D, creatinine clearance greater than 65 mL/min and without diseases or drugs known to influence bone and vitamin D metabolism. INTERVENTION: Cholecalciferol 300,000 IU every 3 months, once at baseline and once at 3 months (intermittent D3 group) or cholecalciferol 1,000 IU/day (daily D3 group). MEASUREMENTS: Serum PTH, 25(OH)D, calcium, bone-specific alkaline phosphatase, ,-C-terminal telopeptide of type I collagen, phosphate, 24-hour urinary calcium excretion. RESULTS: The two groups had similar baseline characteristics. All participants had vitamin D deficiency [25(OH)D<20 ng/mL)], and 36 subjects (60%) had severe deficiency (<10 ng/mL), with no difference between the groups (severe deficiency: intermittent D3 group, n=18; daily D3 group, n=18). After 3 and 6 months, both groups had a significant increase in 25(OH)D and a reduction in PTH. Mean absolute increase±standard deviation of 25(OH)D at 6 months was higher in the intermittent D3 group (22.7±11.8 ng/mL) than in the daily D3 group (13.7±6.7 ng/mL, P<.001), with a higher proportion of participants in the intermittent D3 group reaching desirable serum concentration of 25(OH)D , 30 ng/mL (55% in the intermittent D3 group vs 20% in the daily D3 group, P<.001). Mean percentage decrease of PTH in the two groups was comparable, and at 6 months, a similar proportion of participants reached normal PTH values. 25(OH)D response to cholecalciferol showed a wide variability. In a logistic regression analysis, body mass index and type of treatment appeared to be significantly associated with normalization of 25(OH)D values. CONCLUSION: Cholecalciferol 300,000 IU every 3 months was more effective than 1,000 IU daily in correcting vitamin D deficiency, although the two groups achieved similar effects on PTH at 6 months. Only 55% of the higher-dose intermittent group reached desirable concentrations of 25(OH)D, suggesting that yet-higher doses will be required for adequate vitamin D repletion. [source] Serum intact parathyroid hormone as a predictor of hypocalcaemia after total thyroidectomyANZ JOURNAL OF SURGERY, Issue 11 2005Patsy S. H. Soon Background: Hypocalcaemia from hypoparathyroidism is a complication of total thyroidectomy. The aim of the present study was to determine whether an early postoperative level of serum parathyroid hormone (PTH) after total thyroidectomy predicts the development of significant hypocalcaemia and the need for treatment. Methods: Patients undergoing total thyroidectomy had their serum level of intact PTH checked 1 h after removal of the thyroid gland. Serum calcium level was checked on the following morning. Oral calcium and/or calcitriol was commenced if the patient developed hypocalcaemic symptoms, or if the corrected serum calcium level was <2.0 mmol/L. Results: Seventy-nine patients were included in the present study. Thirteen patients had symptoms of hypocalcaemia on postoperative days 1 or 2 and 66 patients remained asymptomatic. The postoperative intact PTH, day 1 calcium and day 2 calcium was 0.32 ± 0.60 pmol/L, 2.01 ± 0.11 mmol/L, and 2.02 ± 0.16 mmol/L, respectively, for the symptomatic group and 1.98 ± 1.25, 2.21 ± 0.13, and 2.19 ± 0.14, respectively, for the asymptomatic group. Calcium support was given to 25 patients, of whom 14 also required calcitriol. Conclusion: Serum PTH 1-h after total thyroidectomy is a reliable predictor of hypocalcaemia and can allow safe early discharge of patients from hospital. [source] Serum levels of vitamin D, PTH and calcium and breast cancer risk,a prospective nested case,control studyINTERNATIONAL JOURNAL OF CANCER, Issue 9 2010Martin Almquist Abstract Previous studies indicate that calcium and its regulating hormones, i.e., parathyroid hormone (PTH) and vitamin D, might affect breast cancer risk. Evidence also suggests that this relationship could be influenced by menopausal status and BMI. We examined breast cancer risk related to prediagnostic serum levels of vitamin D (25OHD2 and 25OHD3), PTH and calcium using a nested case,control design within the Malmö Diet and Cancer Study. There were 764 incident breast cancer cases, and 764 controls were selected by incidence density matching, using age as the underlying time scale, matching on calendar time at inclusion, menopausal status and age at inclusion. Using logistic regression analysis, odds ratios (OR) with 95% confidence intervals were calculated for breast cancer risk in different quartiles of the analyzed factors. All analyses were adjusted for risk factors for breast cancer, and for levels of albumin, creatinine and phosphate. Analyses were repeated stratified for BMI and menopausal status, and for low vs. high levels of 25OHD3, PTH and calcium. There was a weak, nonsignificant inverse association between breast cancer risk and 25OHD3, and the OR for the 2nd, 3rd and 4th quartiles, as compared to the first, were 0.84 (0.60,1.15), 0.84 (0.60,1.17) and 0.93 (0.66,1.33). Serum calcium was positively associated with breast cancer in premenopausal women (OR for the 4th quartile = 3.10:1.33,7.22 and p for quartile trend = 0.04), and in women with BMI > 25 (OR for the 4th quartile = 1.94:1.12,3.37 and p for trend < 0.01). There was no association between baseline serum PTH and breast cancer risk. [source] Familial Hypocalciuric Hypercalcemia Caused by an R648stop Mutation in the Calcium-Sensing Receptor Gene ,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2002Mika Yamauchi Abstract In this study, we report an 84-year-old female proband in a Japanese family with familial hypocalciuric hypercalcemia (FHH) caused by an R648stop mutation in the extracellular calcium-sensing receptor (CaR) gene. At the age of 71 years, she presented with hypercalcemia (11.4 mg/dl), hypocalciuria (Cca/Ccr = 0.003), hypermagnesemia (2.9 mg/dl), and a high-serum parathyroid hormone (PTH) level (midregion PTH, 3225 [160,520] pg/ml). At the age of 74 years, a family screening was carried out and revealed a total of 9 hypercalcemic individuals (all intact PTH values <62 pg/dl) among 17 family members tested, thus, being diagnosed as FHH. Two and one-half of three clearly enlarged parathyroid glands were resected, because persistently high PTH levels (intact PTH, 292 pg/ml; midregion PTH, 5225 pg/ml) and the presence of a markedly enlarged parathyroid gland by several imaging modalities (ultrasonography, computed tomography [CT], magnetic resonance imaging [MRI], and subtraction scintigraphy) suggested coexistent primary hyperparathyroidism (pHPT); however, hypercalcemia persisted postoperatively. Histological and immunohistochemical examination revealed that the resected parathyroid glands showed lipohyperplasia as well as normally expressed Ki67, vitamin D receptor (VDR), and the CaR. Sequence analysis disclosed that the proband and all affected family members had a heterozygous nonsense (R648stop) mutation in the CaR gene. This mutation is located in the first intracellular loop; thus, it would be predicted to produce a truncated CaR having only one transmembrane domain (TMD) and lacking its remaining TMDs, intracellular loops, and C-terminal tail. Western analysis of biotinylated HEK293 cells transiently transfected with this mutant receptor showed cell surface expression of the truncated protein at a level comparable with that of the wild-type CaR. The mutant receptor, however, exhibited no increase in intracellular free calcium concentration (Ca2+i) when exposed to high extracellular calcium concentrations (Ca2+o). The proband's clinical course was complicated because of associated renal tubular acidosis (RTA) and nephrotic syndrome. However, it was unclear whether their association affected the development of elevated serum PTH and parathyroid gland enlargement. This report is the first to show that an R648stop CaR mutation yields a truncated receptor that is expressed on the cell surface but is devoid of biological activity, resulting in FHH. [source] Primary hyperparathyroidism: new concepts in clinical, densitometric and biochemical featuresJOURNAL OF INTERNAL MEDICINE, Issue 1 2005J. P. BILEZIKIAN Abstract. Primary hyperparathyroidism (PHPT) is characterized most commonly now as an asymptomatic disorder with hypercalcaemia and elevated levels of parathyroid hormone (PTH). The elevation in PTH is detected by both the standard immunoradiometric assays (IRMA) and a more recent IRMA that detects only the 1,84 full-length PTH molecule. The serum calcium concentration is usually <1 mg dL,1 above normal. Recently, another variant of PHPT (normocalcaemic PHPT) has been described in which the serum calcium is normal but the serum PTH is elevated, in the absence of any secondary cause for PTH elevation. Although usually sporadic, PHPT also occurs in inherited syndromes. Skeletal manifestations are appreciated by densitometry showing a typical pattern in which cancellous bone of the lumbar spine is reasonably well preserved whilst the cortical bone of the distal third of the radius is preferentially reduced. Although reduced in incidence, renal stones remain the most common overt complication of PHPT. Other organs are theoretical targets of PHPT such as the neurobehavioural axis and the cardiovascular system. Vitamin D looms as an important determinant of the activity of the PHPT state. The 2002 NIH Workshop on asymptomatic PHPT has led to revised guidelines to help doctors determine who is best advised to have parathyroid surgery and who can be safely followed without surgery. New information about the natural history of PHPT in those who did not undergo surgery has helped to define more precisely who is at-risk for complications. At the NIH workshop, a number of items were highlighted for further investigation such as pharmacological approaches to controlling hypercalcaemia, elevated PTH levels and maintaining bone density. [source] Cardiac dysfunction during exercise in patients with primary hyperparathyroidismBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 9 2000I.-L. Nilsson Background ,Non-traditional' manifestations of primary hyperparathyroidism (HPT) are controversial, and include morbidity, mortality and risk factors for cardiovascular diseases with some prospects of normalization by parathyroidectomy (PTX). This study evaluated previously unexplored data on cardiac function during exercise in HPT. Methods Thirty patients with HPT (mean(s.d.) serum calcium 2·96(0·24) mmol l,1) and 30 normocalcaemic controls (selected randomly from the background population, and matched for age and sex) underwent exercise testing, echocardiography and 24-h ambulatory blood pressure recordings before and a mean of 13 months after PTX. Results HPT was associated with higher systolic blood pressure during exercise (mean(s.d.) 223(28) versus 203(33) mmHg; P = 0·02), which correlated to the left ventricular (LV) mass and serum PTH (P = 0·014, P = 0·004); higher LV mass in men (mean(s.d.) 142(20) versus 113(28) g m,2), which might relate to the hypertrophic effect of PTH; and increased LV isovolumic relaxation times (mean(s.d.) 102(19) versus 91(15) ms; P = 0·018), indicating LV diastolic dysfunction. ST depression during exercise decreased significantly (mean(s.d.) , 1·0(0·9) versus 0·7(0·5) mm; P = 0·028) and LV mass declined in proportion with the time after PTX (P = 0·04 in men). PTX also affected systolic functions, as fractional shortening, atrioventricular plane displacement and systolic index decreased in men (P = 0·05, P = 0·04, P = 0·04). Twenty-four-hour blood pressures were higher in HPT (P = 0·008), when subjects on ,-blockers (seven patients, five controls) were excluded, and were unaltered by PTX. Conclusion LV systolic and diastolic dysfunction occurs in HPT. The diastolic dysfunction seems to diminish with time after PTX, while the positive inotropic effect of calcium in itself may alleviate the systolic dysfunction. © 2000 British Journal of Surgery Society Ltd [source] Failure to normalize parathyroid hormone during treatment of vitamin D deficiency in Asian patientsCLINICAL ENDOCRINOLOGY, Issue 5 2004Steven R. Peacey Summary objective, Vitamin D deficiency and osteomalacia remain commonplace within the Asian community in Bradford. The treatment of vitamin D deficiency and osteomalacia is cheap and effective, but there are few data on long-term outcomes. Studies have suggested that a minority of patients fail to normalize parathyroid hormone (PTH) levels during therapy with vitamin D. This study aimed to determine what proportion of Asian patients with vitamin D deficiency and secondary hyperparathyroidism normalize PTH levels following therapy with oral vitamin D and to examine reasons for failure to normalize PTH. design, This study examined the impact of an oral regimen of vitamin D 800 i.u. (20 micrograms) and calcium 1000 mg daily, on PTH levels within an endocrinology outpatient clinic. patients, 51 (4M:47F) Asian patients, median age 39 years (range 16,77 years) with vitamin D deficiency (25-hydroxyvitamin D < 25 nmol/l) and secondary hyperparathyroidism (PTH > 5·7 pmol/l). measurements, All patients had at least one follow-up measurement of PTH and calcium during treatment. A subgroup of patients gave consent for examination of GP-prescribing records to indirectly asses adherence to therapy. results, PTH normalized in only 28/51 (55%) patients (group N) and failed to normalize in 23/51 (45%) patients (group F). Baseline patient characteristics including: age, basal serum 25-hydroxyvitamin D (25OHD), basal serum PTH, basal serum calcium and post treatment serum calcium, were similar in groups N and F. Mild hypercalcaemia occurred in only two (3·9%) patients. The proportion of prescriptions collected by patients in group N was 75 (17,100)% and in group F was 17 (0,100)%, P < 0·0001. conclusions, This study has demonstrated that long-term oral treatment with vitamin D and calcium, fails to normalize PTH in a significant proportion of patients with vitamin D deficiency and osteomalacia. This is most likely related to lack of adherence to long-term treatment. Improved ways of treating this condition need to be explored. [source] | ||||||||||