scholarly journals Assay-Specific Decision Limits for Two New Automated Parathyroid Hormone and 25-Hydroxyvitamin D Assays

2005 ◽  
Vol 51 (2) ◽  
pp. 395-400 ◽  
Author(s):  
Jean-Claude Souberbielle ◽  
Véronique Fayol ◽  
Corinne Sault ◽  
Ethel Lawson-Body ◽  
André Kahan ◽  
...  
Keyword(s):  
Vitamin D ◽  
Regression Analysis ◽  
Parathyroid Hormone ◽  
Primary Hyperparathyroidism ◽  
Healthy Individuals ◽  
Hydroxyvitamin D ◽  
Low Concentrations ◽  
25 Hydroxyvitamin D ◽  
High Concentrations ◽  
Serum Pth

Abstract Background: The recent development of nonradioactive automated assays for serum parathyroid hormone (PTH) and 25-hydroxyvitamin D (25OHD) has made measurement of these two hormones possible in many laboratories. In this study, we compared two new assays for PTH and 25OHD adapted on an automated analyzer, the LIAISON®, with two manual immunoassays used worldwide. Methods: We studied 228 osteoporotic patients, 927 healthy individuals, 38 patients with primary hyperparathyroidism, and 167 hemodialyzed patients. Serum PTH was measured with the Allegro® and the LIAISON assays, and 25OHD was measured with DiaSorin RIA and the LIAISON assay. Regression analysis was used to calculate decision thresholds for the LIAISON assays that were equivalent to those of the Allegro PTH and DiaSorin 25OHD assays. Results: The 25OHD concentrations obtained with the LIAISON assay and the RIA in osteoporotic patients were well correlated (r = 0.83; P <0.001). Regression and Bland–Altman analyses suggested that the LIAISON 25OHD assay reads lower than the DiaSorin RIA at low concentrations but higher at high concentrations. However, the cutoff (50 nmol/L) used in our laboratories to define vitamin D insufficiency with the DiaSorin RIA is applicable to the LIAISON 25OHD assay. In 927 healthy individuals, the 3rd–97th percentile intervals were 3–80 ng/L and 13–151 nmol/L for the LIAISON PTH and 25OHD concentrations, respectively. However, 506 individuals (54.6%) were vitamin D-insufficient; we therefore considered only the 421 individuals with a LIAISON 25OHD >50 nmol/L as eligible for the reference population for the LIAISON PTH assay. In this group, the 3rd–97th percentile interval for LIAISON PTH was 3–51 ng/L. Considering upper reference limits of 46 and 51 ng/L for the Allegro and LIAISON assays, respectively, the frequency of above-normal PTH concentrations in patients with primary hyperparathyroidism was similar in both assays. Regression analysis between serum PTH measured by the Allegro and LIAISON assays in 167 hemodialyzed patients and the corresponding Bland–Altman analysis of these data suggest that the LIAISON PTH assay tends to read higher than the Allegro assay at low concentrations but lower at high concentrations (>300 ng/L). Conclusions: Because clinical decision limits for both PTH and 25OHD should be assay specific, we propose equivalences between these assays and two manual assays used worldwide. These assay-specific decision limits should help potential users of the LIAISON PTH and 25OHD assays.

scholarly journals Prolonged treatment with vitamin D in postmenopausal women with primary hyperparathyroidism

2012 ◽  
Vol 1 (1) ◽  
pp. 13-21 ◽  
Author(s):  
Ranganathan R Rao ◽  
Harpal S Randeva ◽  
Sailesh Sankaranarayanan ◽  
Murthy Narashima ◽  
Matthias Möhlig ◽  
...  
Keyword(s):  
Vitamin D ◽  
Primary Hyperparathyroidism ◽  
Vitamin D Deficiency ◽  
Postmenopausal Women ◽  
Prolonged Treatment ◽  
Serum 25Ohd ◽  
Hydroxyvitamin D ◽  
Significant Difference ◽  
25 Hydroxyvitamin D ◽  
Serum Pth

Introduction/backgroundVitamin D deficiency further increases circulating parathyroid hormone (PTH) levels in patients with primary hyperparathyroidism (pHPT), with potential detrimental effects on bone mass.MethodsThis was an observational clinical study in consecutive conservatively treated postmenopausal women (n=40) with pHPT and coexistent 25-hydroxyvitamin D deficiency (25OHD ≤50 nmol/l (≤20 ng/ml)). Patients who showed an increase in serum 25OHD above the threshold of vitamin D deficiency (>50 nmol/l; n=28) using treatment with various commonly prescribed vitamin D preparations were, for the purposes of statistical analyses, allocated to the treatment group. Patients who were retrospectively identified as having received no treatment with vitamin D and/or remained vitamin D deficient were considered as non-responders/controls (n=12). Adjusted calcium (adjCa), PTH and 25OHD concentrations were monitored in all subjects up to 54 months (mean observation period of 18±2 months).ResultsProlonged increased vitamin D intake, regardless of the source (serum 25OHD, increase from 32.2±1.7 nmol/l at baseline to 136.4±11.6 nmol/l, P<0.0001), significantly reduced serum PTH (13.3±1.1 vs 10.5±1.0 pmol/l, P=0.0001), with no adverse effects on adjCa levels (2.60±0.03 vs 2.60±0.02 mmol/l, P=0.77) and renal function tests (P>0.73). In contrast, serum PTH remained unchanged (15.8±2.6 vs 16.3±1.9 pmol/l, P=0.64) in patients who remained vitamin D deficient, with a significant difference between groups in changes of PTH (P=0.0003). Intrapartial correlation analyses showed an independent negative correlation of changes in 25OHD with PTH levels (ric=−0.41, P=0.014).ConclusionsProlonged treatment with vitamin D in various commonly prescribed preparations appeared to be safe and significantly reduced PTH levels by 21%.

scholarly journals Plasma 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and parathyroid hormone in familial hypocalciuric hypercalcemia and primary hyperparathyroidism

2008 ◽  
Vol 159 (6) ◽  
pp. 719-727 ◽  
Author(s):  
Signe Engkjær Christensen ◽  
Peter H Nissen ◽  
Peter Vestergaard ◽  
Lene Heickendorff ◽  
Lars Rejnmark ◽  
...  
Keyword(s):  
Vitamin D ◽  
Parathyroid Hormone ◽  
Primary Hyperparathyroidism ◽  
Plasma Levels ◽  
Familial Hypocalciuric Hypercalcemia ◽  
Vitamin D Metabolism ◽  
Hydroxyvitamin D ◽  
Dihydroxyvitamin D ◽  
1,25 Dihydroxyvitamin D ◽  
25 Hydroxyvitamin D

IntroductionFamilial hypocalciuric hypercalcemia (FHH) is a lifelong, benign, inherited condition caused by inactivating mutations in the calcium-sensing receptor (CASR) gene. Both FHH and primary hyperparathyroidism (PHPT) are characterized by elevated P-calcium, normal or elevated plasma-parathyroid hormone (P-PTH), and typically normal renal function. In PHPT, vitamin D metabolism is typically characterized by low plasma levels of 25-hydroxyvitamin D (25OHD), and high plasma levels of 1,25-dihydroxyvitamin D (1,25(OH)2D). In FHH, the vitamin D metabolism is not very well known.ObjectiveTo compare and evaluate plasma 25OHD, 1,25(OH)2D, and PTH in FHH and PHPT.DesignCross-sectional study.MaterialsAbout 66 FHH patients with mutations in the CASR gene, 147 patients with surgically verified PHPT, and 46 controls matched to FHH patients according to age (±5 years), sex, and season. All patients had a P-creatinine <140 μmol/l.MethodsWe measured P-calcium, P-Ca2+, P-albumin, P-creatinine, P-phosphate, P-magnesium, and P-PTH by standard laboratory methods. P-25OHD and P-1,25(OH)2D were measured by RIA or enzyme immunoassay. In FHH, all protein-coding exons in the CASR gene were sequenced and aligned to GenBank reference sequence .ResultsPHPT patients had higher body mass index (2p<0.01), together with higher P-PTH (2p<0.01) and P-1,25(OH)2D (2p<0.01) compared with FHH patients. The groups had similar levels of P-Ca2+ and of P-25OHD. The phenotypic expression of the CASR mutations (as determined by the degree of hypercalcemia) did not influence the levels of P-1,25(OH)2D.ConclusionEven though P-calcium and P-25OHD were comparable, P-1,25(OH)2D and P-PTH differed between FHH and PHPT.

Using Activities of Daily Living Assessments to Measure the Effectiveness of Vitamin D Supplements in Elderly Long-Stay Patients

1987 ◽  
Vol 50 (2) ◽  
pp. 60-62 ◽  
Author(s):  
D Corless ◽  
M Ellis ◽  
E Dawson ◽  
F Fraser ◽  
S Evans ◽  
...  
Keyword(s):  
Vitamin D ◽  
Elderly Patients ◽  
Activities Of Daily Living ◽  
Daily Living ◽  
Controlled Trial ◽  
Double Blind ◽  
Hydroxyvitamin D ◽  
Low Concentrations ◽  
25 Hydroxyvitamin D ◽  
Vitamin D Supplements

Selected activities of daily living were used to measure improvement in independence of long-stay elderly patients known to have low concentrations of plasma 25-hydroxyvitamin D. This was a double-blind random controlled trial lasting between 8 and 40 weeks. No significant changes were found in either group.

Vitamin D Dose Response Study: Effect on Serum 25-Hydroxyvitamin D and Parathyroid Hormone

2011 ◽  
pp. S60-1-S60-1
Author(s):  
J Christopher Gallagher ◽  
Adarsh Sai ◽  
Thomas J Templin ◽  
Lynette M Smith
Keyword(s):  
Vitamin D ◽  
Parathyroid Hormone ◽  
Dose Response ◽  
Hydroxyvitamin D ◽  
25 Hydroxyvitamin D ◽  
Dose Response Study

scholarly journals Role of Vitamin D Supplements in Prevention of Hungry Bone Syndrome after Successful Parathyroidectomy for Primary Hyperparathyroidism: A Prospective Study

2020 ◽  
pp. 145749692096260
Author(s):  
M. A. Salman ◽  
A. Rabiee ◽  
A. Salman ◽  
A. Youssef ◽  
H. E.-D. Shaaban ◽  
...  
Keyword(s):  
Vitamin D ◽  
Primary Hyperparathyroidism ◽  
Vitamin D Deficiency ◽  
Statistical Significance ◽  
Mineral Density ◽  
Hydroxyvitamin D ◽  
Group I ◽  
Vitamin D Levels ◽  
25 Hydroxyvitamin D ◽  
Vitamin D Supplements

Background: We postulated that the preoperative correction of vitamin D levels can significantly reduce the incidence of hunger bone syndrome among patients undergoing parathyroidectomy for primary hyperparathyroidism. Methods: We performed a prospective, randomized, open-label study on 102 patients with primary hyperparathyroidism and coexisting vitamin D deficiency who were scheduled to undergo parathyroidectomy. Patients were divided into the following two groups: group I which included 52 patients who did not receive preoperative vitamin D supplementation; and group II which included 50 patients who received cholecalciferol 1000–2000 IU daily or 50000 IU weekly until they achieve vitamin D levels >20 ng/mL (group IIa = 25 patients) or vitamin D levels >30 ng/mL (group IIb = 25 patients). Results: The incidence of hunger bone syndrome in group IIb was lower than group I and group IIa (8% versus 16% versus 23%, respectively); however, this difference did not reach the level of statistical significance (p = 0.22). Patients with hunger bone syndrome were significantly younger and had higher serum phosphorus, alkaline phosphatase, magnesium, and bone mineral density at baseline than patients without hunger bone syndrome. On the other hand, patients with hunger bone syndrome had significantly lower 25-hydroxyvitamin D at baseline than patients without hunger bone syndrome (p = 0.001). The ROC curve showed that the baseline level of serum 25-hydroxyvitamin D was not an independent discriminator of hunger bone syndrome (area under curve = 0.21 (95% CI: 0.06–0.34); p = 0.011). Conclusion: Preoperative course of vitamin D supplements has no preventive role on the postoperative incidence of hunger bone syndrome among patients with primary hyperparathyroidism and coexisting vitamin D deficiency undergoing parathyroidectomy.

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