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Güneş E, Güneş M. The Impact of Moderate Hypophosphatemia on the Clinical Management of Primary Hyperparathyroidism. Cureus 2023; 15:e44115. [PMID: 37638278 PMCID: PMC10455043 DOI: 10.7759/cureus.44115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/25/2023] [Indexed: 08/29/2023] Open
Abstract
Background and objective The impact of moderate hypophosphatemia (hypoP) on primary hyperparathyroidism (PHPT) and its use as an independent surgical criterion has not been adequately evaluated in the literature. In light of this, we conducted this study to address the scarcity of data on this topic. Methods We conducted a retrospective evaluation of data related to 164 (133 females and 31 males) patients with PHPT who met the criteria for inclusion in the study. HypoP, which is indicated by phosphorus (P) levels lower than 2.5 mg/dL, was found in 78 (47.5%) patients, and moderate hypoP (1-1.99 mg/dL) was found in 25 patients (15.2%). Results PHPT severity was worse in hypoP patients than non-hypoP patients, as evidenced by higher levels of mean serum calcium (12.9 ±1.0 mg/dL vs. 11.1 ±0.3 mg/dL respectively, p<0.001), parathormone (PTH) [median (interquartile range, IQR): 455.3 (455.3) ng/L vs. 124.0 (84.0) ng/L respectively, p<0.001] and mean 24-hour urinary calcium (414.6 ±168.5 mg/day vs. 291.5 ±161.4 mg/day respectively, p=0.026) as well as lower levels of mean BMI (25.6 ±3.9 kg/m2 vs. 29.0 ±4.0 kg/m2 respectively, p=0.18) and mean 25-hydroxy vitamin D3 (13.8 ±7.3 µg/L vs. 18.2 ±7.8 µg/L respectively, p=0.001). Among the whole study population as well as among patients with Ca levels <1.0 mg/dL according to the upper limit of normal, P level was determined to be an independent factor affecting the indication for surgical treatment [β: -1.96,p=0.038, odds ratio (OR): 0.14, 95% confidence interval (CI): 0.02-0.89 and β: -2.3, p=0.034, OR: 0.10, 95% CI: 0.12-0.84 respectively]. Conclusion We found a strong correlation between moderate hypoP and the severity of the biochemical manifestations of PHPT. In asymptomatic PHPT patients, moderate hypoP was predictive of surgical indication, independent of age and level of hypercalcemia.
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Affiliation(s)
- Elif Güneş
- Department of Endocrinology, Metabolism and Diabetes, Health Sciences University, Bursa State Hospital, Bursa, TUR
| | - Mutlu Güneş
- Department of Endocrinology, Metabolism and Diabetes, Health Sciences University, Bursa Yuksek Ihtisas Training and Research Hospital, Bursa, TUR
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Schappacher-Tilp G, Kotanko P, Pirklbauer M. Mathematical Models of Parathyroid Gland Biology: Complexity and Clinical Use. FRONTIERS IN NEPHROLOGY 2022; 2:893391. [PMID: 37674998 PMCID: PMC10479576 DOI: 10.3389/fneph.2022.893391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 04/04/2022] [Indexed: 09/08/2023]
Abstract
Altered parathyroid gland biology is a major driver of chronic kidney disease-mineral bone disorder (CKD-MBD) in patients with chronic kidney disease. CKD-MBD is associated with a high risk of vascular calcification and cardiovascular events. A hallmark of CKD-MBD is secondary hyperparathyroidism with increased parathyroid hormone (PTH) synthesis and release and reduced expression of calcium-sensing receptors on the surface of parathyroid cells and eventually hyperplasia of parathyroid gland cells. The KDIGO guidelines strongly recommend the control of PTH in hemodialysis patients. Due to the complexity of parathyroid gland biology, mathematical models have been employed to study the interaction of PTH regulators and PTH plasma concentrations. Here, we present an overview of various model approaches and discuss the impact of different model structures and complexities on the clinical use of these models.
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Affiliation(s)
- Gudrun Schappacher-Tilp
- Department of Electronic Engineering, University of Applied Science FH Joanneum, Graz, Austria
- Institute for Mathematics and Scientific Computing, University of Graz, Graz, Austria
| | - Peter Kotanko
- Renal Research Institute New York, New York, NY, United States
- Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Markus Pirklbauer
- Department of Internal Medicine IV - Nephrology and Hypertension, Medical University Innsbruck, Innsbruck, Austria
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Meng L, Su C, Shapses SA, Wang X. Total and free vitamin D metabolites in patients with primary hyperparathyroidism. J Endocrinol Invest 2022; 45:301-307. [PMID: 34282553 DOI: 10.1007/s40618-021-01633-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Accepted: 07/05/2021] [Indexed: 12/14/2022]
Abstract
PURPOSE To evaluate total and free vitamin D metabolites and hormone-to-prohormone [1,25(OH)2D/25(OH)D] "activation ratio" in PHPT patients with low or insufficient vitamin D status. METHODS Thirty female patients with primary hyperparathyroidism (PHPT) and 30 age and body mass index (BMI) matched healthy controls were enrolled. Serum levels of calcium, intact parathyroid hormone (iPTH), vitamin D binding protein (DBP), albumin, total 25(OH)D and 1,25(OH)2D were measured. The activation ratio of vitamin D was calculated as total 1,25(OH)2D/25(OH)D. Calculated serum-free 25(OH)D and 1,25(OH)2D levels were also reported. RESULTS Compared to the control subject, patients with PHPT had a lower total 25(OH)D and DBP levels (p < 0.001). The serum concentration of free 25(OH)D and total 1,25(OH)2D were similar between the two groups; but free 1,25(OH)2D levels were about 26% higher in the PHPT patients compared to controls (p < 0.001). PHPT patients had a significantly higher activation ratio (p < 0.01), although their total 25(OH)D were lower than controls. The free (but not total) 1,25(OH)2D level was inversely correlated with DBP (p < 0.01). Both free 1,25(OH)2D levels and activation ratio were positively correlated with iPTH and calcium levels (p < 0.01). The activation ratio was highly correlated with levels of total vitamin D stores and free vitamin D metabolites (p < 0.001). CONCLUSION Patients with PHPT had significantly higher free 1,25(OH)2D levels and activation ratio compared to control subjects. We suggest that levels of free vitamin D metabolites and vitamin D activation ratio may provide additional values for the diagnosis and therapeutic choices in these patient populations with compromised vitamin D status.
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Affiliation(s)
- L Meng
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ, 08901, USA
| | - C Su
- Graduate School of Biomedical Science, Rutgers University, Piscataway, NJ, 08854, USA
| | - S A Shapses
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ, 08901, USA
| | - X Wang
- Division of Endocrinology, Department of Medicine, Rutgers University-Robert Wood Johnson Medical School, New Brunswick, NJ, 08093, USA.
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Matzen J, Bislev LS, Sikjær T, Rolighed L, Hitz MF, Eiken P, Hermann AP, Jensen JEB, Abrahamsen B, Rejnmark L. The effect of parathyroidectomy compared to non-surgical surveillance on kidney function in primary hyperparathyroidism: a nationwide historic cohort study. BMC Endocr Disord 2022; 22:14. [PMID: 34991581 PMCID: PMC8734053 DOI: 10.1186/s12902-021-00918-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 12/14/2021] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Patients with primary hyperparathyroidism (pHPT) and impaired kidney function (estimated glomerular filtration rate (eGFR) < 60 mL/min) are offered parathyroidectomy (PTX) to protect them from further complications. Surprisingly, two recent uncontrolled cohort studies have suggested a further decrease in kidney function following PTX. We aimed to examine the effects of PTX compared to non-surgical surveillance on kidney function in pHPT patients. METHODS Historic cohort study. From the Danish National Patient Registry (NPR) and major medical biochemistry laboratories in Denmark, we identified 3585 patients with biochemically confirmed pHPT among whom n = 1977 (55%) were treated with PTX (PTX-group) whereas n = 1608 (45%) were followed without surgery (non-PTX group). Baseline was defined as time of diagnosis and kidney function was re-assessed 9-15 months after PTX (PTX group) or 9-15 months after diagnosis (non-PTX group). RESULTS At follow-up, eGFR had decreased significantly in the PTX- compared to the non-PTX-group (median - 4% vs. - 1%, p < 0.01). Stratification by baseline eGFR showed that the decrease was significant for those with a baseline eGFR value of 80-89 and > 90 mL/min, but not for those with lower eGFR values. Findings did not differ between patients with mild compared to moderate/severe hypercalcemia. However, after mutual adjustments, we identified baseline levels of calcium, PTH, and eGFR as well as age and treatment (PTX vs. no-PTX) as independent predictors for changes in kidney function. CONCLUSION Compared to non-surgical surveillance, PTX is associated with a small but significant decrease in kidney function in pHPT patients with an initial normal kidney function.
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Affiliation(s)
- Josephine Matzen
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Lise Sofie Bislev
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Tanja Sikjær
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Lars Rolighed
- Department of Otorhinolaryngology, Aarhus University Hospital, Aarhus, Denmark
| | - Mette Friberg Hitz
- Department of Medical Endocrinology, Zealand University Hospital Køge, Køge, Denmark
- Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Pia Eiken
- Department of Endocrinology, Bispebjerg, Copenhagen University Hospital, Copenhagen, Denmark
| | | | - Jens-Erik Beck Jensen
- Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Bo Abrahamsen
- Department of Clinical Research, University of Southern Denmark and Odense University Hospital, Odense C, Denmark
- Holbæk Hospital, Department of Medicine, Holbæk, Denmark
| | - Lars Rejnmark
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
- Institute of Clinical Medicine, Aarhus University, Aarhus, Denmark
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Bittker SS. Elevated Levels of 1,25-Dihydroxyvitamin D in Plasma as a Missing Risk Factor for Celiac Disease. Clin Exp Gastroenterol 2020; 13:1-15. [PMID: 32021373 PMCID: PMC6956711 DOI: 10.2147/ceg.s222353] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 11/13/2019] [Indexed: 02/06/2023] Open
Abstract
The prevalence of celiac disease (CD) has increased significantly in some developed countries in recent decades. Potential risk factors that have been considered in the literature do not appear to provide a convincing explanation for this increase. This has led some researchers to hypothesize that there is a "missing environmental factor" that increases the risk of CD. Based on evidence from the literature, the author proposes that elevation in plasma levels of 1,25-dihydroxyvitamin D [1,25(OH)2D] is a missing risk factor for CD, and relatedly that significant oral vitamin D exposure is a "missing environmental factor" for CD. First, elevated plasma levels of 1,25(OH)2D are common in CD, especially in the newly diagnosed. Second, nine distinct conditions that increase plasma levels of 1,25(OH)2D are either associated with CD or have indications of such an association in the literature. Third, a retrospective study shows that sustained oral vitamin D supplementation in infancy is associated with increased CD risk, and other studies on comorbid conditions support this association. Fourth, large doses of oral vitamin D upregulate many of the same cytokines, chemokines, and toll-like receptors that are upregulated in CD. Fifth, epidemiological evidence, such as the timing of the inception of a CD "epidemic" in Sweden, the increased prevalence of CD in Finland and the United States in recent decades, the unusually low prevalence of CD in Germany, and the differential in prevalence between Finnish Karelians and Russian Karelians, may all be explained by oral vitamin D exposure increasing CD risk. The same is true of some seemingly contradictory results in the literature on the effects of breastfeeding on CD risk. If future research validates this hypothesis, adjustments to oral vitamin D consumption among those who have genetic susceptibility may decrease the risk of CD in these individuals.
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Bittker SS, Bell KR. Potential risk factors for celiac disease in childhood: a case-control epidemiological survey. Clin Exp Gastroenterol 2019; 12:303-319. [PMID: 31308721 PMCID: PMC6615019 DOI: 10.2147/ceg.s210060] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 05/08/2019] [Indexed: 12/30/2022] Open
Abstract
Background: Celiac disease (CD) prevalence has increased significantly in recent decades in some developed countries. Yet the environmental factors in the existing literature do not appear to provide a satisfactory explanation for this increase. Objective: To determine whether nine variables are associated with CD in children. These variables are: incidence of ear infection before 2 years old, courses of antibiotics before 2 years old, duration of breastfeeding, vitamin D drop exposure in infancy, vitamin D supplement exposure between 2–3 years old, age at gluten introduction into the diet, fat content of cow’s milk consumed between 2–3 years old, quantity of cow’s milk consumed between 2–3 years old, and type of water consumed at 2 years old. Methods: An Internet-based survey was conducted among parents living in the US with at least one biological child between 3 and 12 years old. Potential participants were informed about the survey through social media, websites, electronic newsletters, and advertisements. Results: After exclusions, there remained 332 responses associated with children with CD (cases), and 241 responses associated with children who do not have CD (controls). In this data set, skim milk as the primary form of liquid cow’s milk consumed between 2–3 years old (adjusted odds ratio [aOR]=3.556, CI=1.430–10.22, P=0.010), vitamin D drops administered for more than 3 months (aOR=1.749, CI=1.079–2.872, P=0.025), courses of antibiotics (aOR=1.133, CI=1.037–1.244, P=0.007), and incidence of ear infection (aOR=1.183, CI=1.041–1.348, P=0.010) are all associated with CD in children. Conclusions: This study is the first to find an association between skim milk consumption and CD and vitamin D drop use for greater than 3 months and CD. It also adds to evidence that early life exposure to antibiotics and early life infection, specifically ear infection, are associated with CD. ![]()
Point your SmartPhone at the code above. If you have a QR code reader the video abstract will appear. Or use: https://youtu.be/y9aThwSZHoE
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Affiliation(s)
- Seth Scott Bittker
- Interdisciplinary Center for Innovative Theory and Empirics (INCITE), Columbia University, New York, New York, US
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7
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Ivison FM, Hinchliffe E, Howarth N, Pickersgill M, Tetlow L. Development of a mass spectrometry method for 1,25-dihydroxy vitamin D3 using immunoextraction sample preparation. Ann Clin Biochem 2019; 56:646-653. [PMID: 31037955 DOI: 10.1177/0004563219847225] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Background 1,25-Dihydroxy vitamin D3 (DHVD) is the active metabolite of vitamin D, required to maintain blood calcium concentrations. Measurement has proved challenging as it circulates in picomolar concentrations and must be differentiated from other dihydroxyvitamin D species. Clinically, it is essential to be able to determine the cause of hypercalcaemia, which may be due to DHVD excess. Methods The liquid chromatography-mass spectrometry (LCMS) assay which has been developed uses immunoextraction of 0.5 mL serum followed by Amplifex™ derivatization of the dried eluent, with the analysis using the SCIEX 6500+ instrument taking a run time of 11 min. Results The limit of quantitation was determined (15 pmol/L) and the method is linear up to at least 600 pmol/L. Repeatability ranged from 6.1% at 23 pmol/L to 2.5% at 172 pmol/L and intermediate imprecision was 15.6% at 26 pmol/L to 8.3% at 173 pmol/L. The method is unaffected by icterus, haemolysis or lipaemia. Good performance was achieved with the samples from the vitamin D external quality assessment scheme, demonstrating a negative bias compared with the all lab trimmed mean (average –13.8%) and the specific method group (average –7.75%). A negative bias was observed across the concentration range found in 78 patient samples in comparison to a commercial radioimmunoassay (mean –47.8%). This was not unexpected and is likely due to better specificity of the mass spectrometry assay and the lack of a commutable standard reference calibrator. Conclusions We have developed a sensitive and robust LCMS method for the analysis of DHVD in serum, utilizing immunoextraction and derivatization to provide specificity.
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Affiliation(s)
- Fiona M Ivison
- Department of Clinical Biochemistry, Manchester University NHS Foundation Trust, Manchester, UK
| | - Edward Hinchliffe
- Department of Clinical Biochemistry, Manchester University NHS Foundation Trust, Manchester, UK
| | - Neil Howarth
- Department of Clinical Biochemistry, Manchester University NHS Foundation Trust, Manchester, UK
| | - Mandy Pickersgill
- Department of Clinical Biochemistry, Manchester University NHS Foundation Trust, Manchester, UK
| | - Lesley Tetlow
- Department of Clinical Biochemistry, Manchester University NHS Foundation Trust, Manchester, UK
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8
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Sum M, Larner D, Hewison M, Bilezikian JP. Brown tumors of primary hyperparathyroidism may be a source of extrarenal 1,25-dihydroxyvitamin D production. Endocrine 2018; 60:524-527. [PMID: 29556950 DOI: 10.1007/s12020-018-1579-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 03/06/2018] [Indexed: 10/17/2022]
Affiliation(s)
- Melissa Sum
- Department of Medicine, New York University Langone Health, New York, NY, 10016, USA.
| | - Dean Larner
- Institute of Metabolism & Systems Research, University of Birmingham, Birmingham, UK
| | - Martin Hewison
- Institute of Metabolism & Systems Research, University of Birmingham, Birmingham, UK
| | - John P Bilezikian
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA
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Kaderli RM, Riss P, Geroldinger A, Selberherr A, Scheuba C, Niederle B. Factors influencing pre-operative urinary calcium excretion in primary hyperparathyroidism. Clin Endocrinol (Oxf) 2017; 87:97-102. [PMID: 28383779 DOI: 10.1111/cen.13348] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 03/09/2017] [Accepted: 04/03/2017] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Normal or elevated 24-hour urinary calcium (Ca) excretion is a diagnostic marker in primary hyperparathyroidism (PHPT). It is used to distinguish familial hypocalciuric hypercalcaemia (FHH) from PHPT by calculating the Ca/creatinine clearance ratio (CCCR). The variance of CCCR in patients with PHPT is considerable. The aim of this study was to analyse the parameters affecting CCCR in patients with PHPT. DESIGN The data were collected prospectively. Patients with sporadic PHPT undergoing successful surgery were included in a retrospective analysis. PATIENTS The analysis covered 381 patients with pre-operative workup 2 days before removal of a solitary parathyroid adenoma. MEASUREMENTS The impact of serum Ca and 25-hydroxyvitamin D3 (25-OH D3) on CCCR. RESULTS The coefficient of determination (R2 ) in the multivariable model for CCCR consisting of age, Ca, 25-OH D3, 1,25-dihydroxyvitamin D3 (1,25-(OH)2 D3), testosterone (separately for males and females), intact parathyroid hormone (iPTH) and osteocalcin was 25.8%. The only significant parameters in the multivariable analysis were 1,25-(OH)2 D3 and osteocalcin with a drop in R2 of 15.4% (P<.001) and 2.4% (P=.006), respectively. Bone mineral densities at the lumbar spine, distal radius and left femoral neck were not associated with CCCR (r=-.08, r=-.10 and r=-0.09). CONCLUSIONS In multivariable analysis, 1,25-(OH)2 D3 and osteocalcin were the only factors correlating with CCCR. Vitamin D3 replacement may therefore impair the diagnostic value of CCCR and increase the importance of close monitoring of urinary Ca excretion during treatment.
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Affiliation(s)
- Reto M Kaderli
- Section of Endocrine Surgery, Division of General Surgery, Department of Surgery, Medical University of Vienna, Wien, Austria
- Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Philipp Riss
- Section of Endocrine Surgery, Division of General Surgery, Department of Surgery, Medical University of Vienna, Wien, Austria
| | - Angelika Geroldinger
- Section for Clinical Biometrics, Centre for Medical Statistics, Informatics and Intelligent Systems (CeMSIIS), Medical University of Vienna, Wien, Austria
| | - Andreas Selberherr
- Section of Endocrine Surgery, Division of General Surgery, Department of Surgery, Medical University of Vienna, Wien, Austria
| | - Christian Scheuba
- Section of Endocrine Surgery, Division of General Surgery, Department of Surgery, Medical University of Vienna, Wien, Austria
| | - Bruno Niederle
- Section of Endocrine Surgery, Division of General Surgery, Department of Surgery, Medical University of Vienna, Wien, Austria
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Abstract
Vitamin D testing is part of laboratory practice since more than 30 years but has become a routine parameter only recently, due to a highly increasing amount of research in the field resulting in new clinical applications. Vitamin D actually represents a family of molecules of which 25OH Vitamin D and 1,25(OH)2 Vitamin D, under their D3 and D2 forms, are the most important to date. Physical detection methods and immunoassays exist for both molecules and are being reviewed and discussed. New developments in the measurement of C3-epi-25OH Vitamin D, 24,25(OH)2 Vitamin D, and free/bioavailable 25OH Vitamin D are also presented. The future of Vitamin D testing is considered based on the evolution of laboratories and based on the scientific research that is currently performed.
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Affiliation(s)
- N Heureux
- DIAsource Immunoassays, Louvain-la-Neuve, Belgium.
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11
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Riss P, Kammer M, Selberherr A, Bichler C, Kaderli R, Scheuba C, Niederle B. The influence of thiazide intake on calcium and parathyroid hormone levels in patients with primary hyperparathyroidism. Clin Endocrinol (Oxf) 2016; 85:196-201. [PMID: 26921840 DOI: 10.1111/cen.13046] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 02/17/2016] [Accepted: 02/22/2016] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The effects of thiazide medication in patients with primary hyperparathyroidism (PHPT) have so far not been elucidated. The aim of this study was to analyse the extent to which the administration of thiazides may influence biochemical parameters and therefore the diagnosis of PHPT in a large cohort of patients. DESIGN AND PATIENTS The biochemical parameters of 1066 patients with PHPT were analysed, and drug history was documented. Calcium (Ca)/creatinine clearance ratio (CCCR) was calculated. The results of patients given thiazides (n = 170) and those not given thiazides (n = 896) were analysed and compared. MEASUREMENTS Twenty-four-hour urinary calcium excretion (24hU), albumin-corrected serum calcium, PTH, creatinine, 1,25OH- and 25OH-vitamin D were measured, and CCCR was calculated. RESULTS 24hUC a and CCCR were significantly lower in patients on thiazides (P = 0·02 and P = 0·0068, resp.), and serum creatinine was significantly higher in those subjects (P < 0·0001). Serum Ca levels only proved different in an analysis of covariance among patients younger than 60 years (P = 0·003). Nevertheless, PTH was not different in both groups (P = 0·917). CONCLUSIONS According to recently published guidelines, 24hUCa measurement is necessary to give indication for surgery in asymptomatic patients and to distinguish between PHPT and familial hypocalciuric hypercalcaemia [FHH]. Thiazides significantly decrease 24hUC a , yet neither increase serum Ca nor influence PTH levels in patients with PHPT. However, discontinuing thiazides is crucial for a correct CCCR calculation to pre-operatively rule out FHH. As a consequence, the withdrawal of thiazide medication must be recommended for the diagnosis of PHPT prior to surgery.
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Affiliation(s)
- Philipp Riss
- Section of Endocrine Surgery, Division of General Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Michael Kammer
- Section for Clinical Biometrics, Center for Medical Statistics, Informatics and Intelligent Systems (CeMSIIS), Medical University of Vienna, Vienna, Austria
| | - Andreas Selberherr
- Section of Endocrine Surgery, Division of General Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Christoph Bichler
- Section of Endocrine Surgery, Division of General Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Reto Kaderli
- Section of Endocrine Surgery, Division of General Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Christian Scheuba
- Section of Endocrine Surgery, Division of General Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Bruno Niederle
- Section of Endocrine Surgery, Division of General Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
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Pasquali M, Tartaglione L, Rotondi S, Muci ML, Mandanici G, Farcomeni A, Marangella M, Mazzaferro S. Calcitriol/calcifediol ratio: An indicator of vitamin D hydroxylation efficiency? BBA CLINICAL 2015; 3:251-6. [PMID: 26676064 PMCID: PMC4661572 DOI: 10.1016/j.bbacli.2015.03.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 03/05/2015] [Accepted: 03/06/2015] [Indexed: 12/11/2022]
Abstract
Background Calcifediol (25D) availability is crucial for calcitriol (1,25D) synthesis, but regulation of vitamin D hydroxylases is majorly responsible for 1,25D synthesis. The net efficiency of vitamin D hydroxylases might be informative. We assume that the ratio between calcitriol and calcifediol (25D/1,25D) serum concentrations could suggest the vitamin D hydroxylation efficiency. Methods We evaluated 25D/1,25D in different patient populations: hemodialysis (HD, n = 76), CKD stage 2–5 (n = 111), renal transplant (TX, n = 135), patients with no renal disease (No-CKD, n = 290), and primary hyperparathyroidism (PHP, n = 20). Results The geometric mean of 1,25D/25D (pg/ng) averaged 1.11 (HD), 1.36 (CKD), 1.77 (TX), 2.22 (No-CKD), and 4.11 (PHP), with a progressive increment from HD to PHP (p-value for the trend <0.001). Each clinical condition elicited a significant effect on 25D/1,25D (p < 0.0001) and adjusted multivariate analysis indicated levels of Cas, Ps, PTH, and 25D as predictors of 25D/1,25D. Both in vitamin D deficient and replete subjects (25D< or ≥20 ng/ml) 25D/1,25D associated with each clinical condition (p < 0.0001) and mean values increased progressively from HD to PHP (p-values for the trend <0.0001). Regression analysis between 25D (substrate) and 25D/1,25D (efficiency) revealed an exponential negative correlation in No-CKD (r2Exp = 0.53, p < 0.001) with sharp increments of 25D/1,25D when 25D values are <20 ng/ml. At variance, in CKD (r2lin = 0.19) and in TX (r2lin = 0.32) the regression was linear as if, in case of deficit, some inhibition of the system were operating. Conclusion and General significance In conclusion 1,25D/25D can reflect the efficiency of vitamin D hydroxylases more than separate evaluation of 25D and 1,25D and can facilitate the therapeutic choices in different patient populations. 1,25D/25D ratio could represent an index of vitamin D hydroxylation efficiency. 1,25D/25D ratio progressively increases from HD to CKD, TX, No-CKD and PHP. Each of these clinical conditions affected the value of the ratio. In selected populations 1,25D/25D ratio could guide substitutive therapeutic choices.
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Affiliation(s)
- Marzia Pasquali
- Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Sapienza University of Rome, Italy
| | - Lida Tartaglione
- Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Sapienza University of Rome, Italy
| | - Silverio Rotondi
- Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Sapienza University of Rome, Italy
| | - Maria Luisa Muci
- Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Sapienza University of Rome, Italy
| | - Giusi Mandanici
- Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Sapienza University of Rome, Italy
| | - Alessio Farcomeni
- Dept. of Public Health and Infectious Diseases, Sapienza University of Rome, Italy
| | | | - Sandro Mazzaferro
- Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Sapienza University of Rome, Italy
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13
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Hendrickson CD, Castro Pereira DJ, Comi RJ. Renal impairment as a surgical indication in primary hyperparathyroidism: do the data support this recommendation? J Clin Endocrinol Metab 2014; 99:2646-50. [PMID: 24758187 DOI: 10.1210/jc.2014-1379] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
CONTENT Management of primary hyperparathyroidism has evolved over the past two decades, yet impaired renal function has consistently been a surgical indication. This recommendation has been based upon the historical association between primary hyperparathyroidism and renal impairment, and a review of the literature is needed to determine whether such a recommendation is warranted. EVIDENCE ACQUISITION AND SYNTHESIS PubMed was utilized to identify English-language articles published between January 1990 and February 2014 using keywords related to hyperparathyroidism and renal function. The keywords were "primary hyperparathyroidism," "surgery," "parathyroidectomy," "kidney," "renal," "glomerular filtration rate," and "creatinine." Of the 1926 articles obtained with this search, all articles germane to the topic that quantified the relationship between primary hyperparathyroidism and renal function were included. All references within these articles were investigated for inclusion. When helpful, data tables were constructed to summarize the results succinctly. CONCLUSIONS A secondary elevation of PTH levels has not been consistently shown to occur at the threshold currently indicated for surgical intervention. While renal impairment is seen with more significant disease, mild asymptomatic primary hyperparathyroidism has not been conclusively associated with renal impairment. Furthermore, there is no evidence to suggest that surgically curing primary hyperparathyroidism via a parathyroidectomy has any impact upon renal function.
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Affiliation(s)
- Chase D Hendrickson
- Sections of Endocrinology, Diabetes, and Metabolism (C.D.H., R.J.C.) and Nephrology and Hypertension (D.J.C.P.), Dartmouth-Hitchcock Medical Center, Department of Medicine, Lebanon, New Hampshire 03756
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14
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Murray RD, Holthouser K, Clark BJ, Salyer SA, Barati MT, Khundmiri SJ, Lederer ED. Parathyroid hormone (PTH) decreases sodium-phosphate cotransporter type IIa (NpT2a) mRNA stability. Am J Physiol Renal Physiol 2013; 304:F1076-85. [DOI: 10.1152/ajprenal.00632.2012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The acute inhibitory effects of parathyroid hormone (PTH) on proximal tubule Na+-K+-ATPase (Na-K) and sodium-dependent phosphate (NaPi) transport have been extensively studied, while little is known about the chronic effects of PTH. Patients with primary hyperparathyroidism, a condition characterized by chronic elevations in PTH, exhibit persistent hypophosphatemia but not significant evidence of salt wasting. We postulate that chronic PTH stimulation results in differential desensitization of PTH responses. To address this hypothesis, we compared the effects of chronic PTH stimulation on Na-Pi cotransporter (Npt2a) expression and Na-K activity and expression in Sprague Dawley rats, transgenic mice featuring parathyroid-specific cyclin D1 overexpression (PTH-D1), and proximal tubule cell culture models. We demonstrated a progressive decrease in brush-border membrane (BBM) expression of Npt2a from rats treated with PTH for 6 h or 4 days, while Na-K expression and activity in the basolateral membranes (BLM) exhibited an initial decrease followed by recovery to control levels by 4 days. Npt2a protein expression in PTH-D1 mice was decreased relative to control animals, whereas levels of Na-K, NHERF-1, and PTH receptor remained unchanged. In PTH-D1 mice, NpT2a mRNA expression was reduced by 50% relative to control mice. In opossum kidney proximal tubule cells, PTH decreased Npt2a mRNA levels. Both actinomycin D and cycloheximide treatment prevented the PTH-mediated decrease in Npt2a mRNA, suggesting that the PTH response requires transcription and translation. These findings suggest that responses to chronic PTH exposure are selectively regulated at a posttranscriptional level. The persistence of the phosphaturic response to PTH occurs through posttranscriptional mechanisms.
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Affiliation(s)
- Rebecca D. Murray
- Department of Physiology and Biophysics, University of Louisville, Louisville, Kentucky
| | - Kristine Holthouser
- Department of Physiology and Biophysics, University of Louisville, Louisville, Kentucky
- Department of Medicine/Kidney Disease Program, University of Louisville, Louisville, Kentucky; and
| | - Barbara J. Clark
- Department of Biochemistry, University of Louisville, Louisville, Kentucky
| | - Sarah A. Salyer
- Department of Physiology and Biophysics, University of Louisville, Louisville, Kentucky
| | - Michelle T. Barati
- Department of Medicine/Kidney Disease Program, University of Louisville, Louisville, Kentucky; and
| | - Syed J. Khundmiri
- Robley Rex Veterans Affairs Medical Center, Louisville, Kentucky
- Department of Physiology and Biophysics, University of Louisville, Louisville, Kentucky
- Department of Medicine/Kidney Disease Program, University of Louisville, Louisville, Kentucky; and
| | - Eleanor D. Lederer
- Robley Rex Veterans Affairs Medical Center, Louisville, Kentucky
- Department of Physiology and Biophysics, University of Louisville, Louisville, Kentucky
- Department of Medicine/Kidney Disease Program, University of Louisville, Louisville, Kentucky; and
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15
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Starup-Linde J, Waldhauer E, Rolighed L, Mosekilde L, Vestergaard P. Renal stones and calcifications in patients with primary hyperparathyroidism: associations with biochemical variables. Eur J Endocrinol 2012; 166:1093-100. [PMID: 22474170 DOI: 10.1530/eje-12-0032] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To study the prevalence of renal stones and nephrocalcinosis in patients with primary hyperparathyroidism (PHPT) and to appraise biochemical variables as risk factors for developing renal calcifications. DESIGN Cross-sectional. MATERIALS AND METHODS All patients (n=177) undergoing diagnostic evaluation and surgery for PHPT at Aarhus University Hospital between 2007 and 2009. All patients underwent routine spiral CT scans of the abdomen to determine the presence or absence of renal calcifications. RESULTS A total of 45 patients (25.4%, 95% confidence intervals: 19.0-31.4%) had renal stones (15.3%) and/or renal calcifications (10.2%) on the CT scans. Compared with those without calcification (n=132), the group with calcification had a significantly lower plasma creatinine level (67.0±25.1 vs 74.6±17.5 μmol/l, 2P=0.03). Moreover, CaE was higher in PHPT patients with renal calcification than in PHPT patients without (0.91±0.28 vs 0.74±0.40 mmol/mmol, 2P=0.02). The other measured or derived biochemical variables were similar in the two groups. No biochemical variable was predictive for renal calcifications in a multiple regression analysis. CONCLUSION We found a high prevalence of renal calcifications among PHPT patients but no deterioration of renal function. The occurrence of calcifications was related to low plasma creatinine and a high urine calcium/creatinine ratio. However, biochemical markers in general were poor predictors for the risk of renal stones or nephrocalcinosis indicating that routine image diagnostics may be needed for the identification of these complications in order to establish indication for surgery and ensure proper treatment.
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Affiliation(s)
- Jakob Starup-Linde
- Osteoporosis Clinic, Department of Endocrinology and Internal Medicine, Aarhus University Hospital THG, Tage Hansens Gade 2, Aarhus, Denmark
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16
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Christensen SE, Nissen PH, Vestergaard P, Mosekilde L. Familial hypocalciuric hypercalcaemia: a review. Curr Opin Endocrinol Diabetes Obes 2011; 18:359-70. [PMID: 21986511 DOI: 10.1097/med.0b013e32834c3c7c] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
PURPOSE OF REVIEW Hypercalcaemia is a potentially life-threatening condition. Familial hypocalciuric hypercalcaemia (FHH) is a rare, lifelong, benign condition. It is important to separate this condition from other hypercalcaemic states such as hypercalcaemia of malignancy and primary hyperparathyroidism (PHPT). RECENT FINDINGS FHH is caused by inactivating mutations in the calcium sensing receptor (CASR) gene leading to a general calcium-hyposensitivity, compensatory hypercalcaemia and hypocalciuria. The inheritance of FHH is autosomal dominant. Similar to PHPT, FHH is characterized by hypercalcaemia, unsuppressed or elevated plasma parathyroid hormone, and typically normal renal function. The phenotype is normal, and hypercalcaemic symptoms are generally absent. The hallmark is a relatively low urine calcium excretion in contrast to PHPT, in which urine calcium excretion is increased. The vitamin D status as measured by plasma 25-hydroxyvitamin D has been reported to be normal with normal seasonal variations, whereas plasma 1,25-dihydroxyvitamin D has been found slightly increased compared to normal. Bone mineral density Z-scores are normal in spite of a slightly increased bone turnover. Differential diagnoses include mainly PHPT, but in some cases also hypercalcaemia of malignancy and use of thiazide diuretics. SUMMARY In general, FHH does not require treatment. We recommend a two-step diagnostic procedure. First, the calcium/creatinine clearance ratio is measured from a 24-h urine. Second, all patients with calcium/creatinine clearance ratio of 0.020 or less are tested for mutations in the CASR gene. The diagnostic sensitivity of this setup is 98%.
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Affiliation(s)
- Signe E Christensen
- Department of Medicine and Endocrinology, Aarhus University Hospital, Aarhus C, Denmark.
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17
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Exogenous PTH and endogenous 1,25-dihydroxyvitamin D are complementary in inducing an anabolic effect on bone. J Bone Miner Res 2008; 23:1257-66. [PMID: 18348699 DOI: 10.1359/jbmr.080318] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
PTH and 1,25(OH)(2)D each exert dual anabolic and catabolic skeletal effects. We assessed the potential interaction of PTH and 1,25(OH)(2)D in promoting skeletal anabolism by comparing the capacity of exogenous, intermittently injected PTH(1-34) to produce bone accrual in mice homozygous for the 1 alpha(OH)ase-null allele [1 alpha(OH)ase(-/-) mice] and in wildtype mice. In initial studies, 3-mo-old wildtype mice were either injected once daily (40 microg/kg) or infused continuously (120 microg/kg/d) with PTH(1-34) for up to 1 mo. Infused PTH reduced BMD, increased the bone resorption marker TRACP-5b, and raised serum calcium but did not increase serum 1,25(OH)(2)D. Injected PTH increased serum 1,25(OH)(2)D and BMD, raised the bone formation marker osteocalcin more than did infused PTH, and did not produce sustained hypercalcemia as did PTH infusion. In subsequent studies, 3-mo-old 1 alpha(OH)ase(-/-) mice, raised on a rescue diet, and wildtype littermates were injected with PTH(1-34) (40 microg/kg) either once daily or three times daily for 1 mo. In 1 alpha(OH)ase(-/-) mice, baseline bone volume (BV/TV) and bone formation (BFR/BS) were lower than in wildtype mice. PTH administered intermittently increased BV/TV and BFR/BS in a dose-dependent manner, but the increases were always less than in wildtype mice. These studies show that exogenous PTH administered continuously resorbs bone without raising endogenous 1,25(OH)(2)D. Intermittently administered PTH can increase bone accrual in the absence of 1,25(OH)(2)D, but 1,25(OH)(2)D complements this PTH action. An increase in endogenous 1,25(OH)(2)D may therefore facilitate an optimal skeletal anabolic response to PTH and may be relevant to the development of improved therapeutics for enhancing skeletal anabolism.
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18
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Abstract
Today, primary hyperparathyroidism (PHPT) in the developed countries is typically a disease with few or no obvious clinical symptoms. However, even in the asymptomatic cases the endogenous excess of PTH increases bone turnover leading to an insidious reversible loss of cortical and trabecular bone because of an expansion of the remodelling space and an irreversible loss of cortical bone due to increased endocortical resorption. In contrast trabecular bone structure and integrity to a large extent is maintained and there may be a slight periosteal expansion. Most studies have reported decreased bone mineral density (BMD) in PHPT mainly located at cortical sites, whereas sites rich in trabecular bone only show a modest reduction or even a slight increase in BMD. The frequent occurrence of vitamin D insufficiency and deficiency in PHPT and increased plasma FGF23 levels may also contribute to the decrease in BMD. The effect of smoking is unsolved. Epidemiological studies have shown that the relative risk of spine and nonspine fractures is increased in untreated PHPT starting up to 10 years before the diagnosis is made. Successful surgery for PHPT normalizes bone turnover, increases BMD and decreases fracture risk based on larger epidemiological studies. However, 10 years after surgery fracture risk appears to increase again due to an increase in forearm fractures. There are no randomized controlled studies (RCTs) demonstrating a protective effect of medical treatment on fracture risk in PHPT. Less conclusive studies suggest that vitamin D supplementation may have a beneficial effect on plasma PTH and BMD in vitamin D deficient PHPT patients. Hormone replacement therapy (HRT) and maybe SERM appear to reduce bone turnover and increase BMD. However, their nonskeletal side-effects preclude their use for this purpose. Bisphosphonates reduce bone turnover and increase BMD in PHPT as in osteoporosis and may be a therapeutical option in selected patients with low BMD. Obviously, there is a need for larger RCTs with fractures as end-points that appraise this possibility. Calcimimetics reduce plasma calcium and PTH in PHPT but has no beneficial effect on bone turnover or BMD. In symptomatic hypercalcaemic PHPT with low BMD where curative surgery is impossible or contraindicated a combination of a calcimimetic and a bisphosphonate may be an undocumented therapeutical option that needs further evaluation.
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Affiliation(s)
- Leif Mosekilde
- Department of Endocrinology and Metabolism C, Aarhus University Hospital, DK 8000, Aarhus C, Denmark.
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19
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Moosgaard B, Christensen SE, Vestergaard P, Heickendorff L, Christiansen P, Mosekilde L. Vitamin D metabolites and skeletal consequences in primary hyperparathyroidism. Clin Endocrinol (Oxf) 2008; 68:707-15. [PMID: 17980013 DOI: 10.1111/j.1365-2265.2007.03109.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND Primary hyperparathyroidism (PHPT) is associated with reduced bone mineral density (BMD) mainly at sites rich in cortical bone. However, successful parathyroidectomy causes an increase in BMD especially at sites rich in trabecular bone. Plasma 25-hydroxyvitamin D (25OHD) levels are typically reduced and plasma 1,25-dihydroxyvitamin D [1,25(OH)(2)D] slightly increased in PHPT. These variations in vitamin D metabolites may influence variations in BMD and fracture risk. AIM To investigate relations between preoperative vitamin D metabolites and skeletal consequences in patients with untreated PHPT and to appraise the influence of preoperative vitamin D metabolites on postoperative changes in BMD. Design Cross-sectional and cohort study. MATERIALS Two hundred and forty-six consecutive Caucasian PHPT patients aged 19-91 years. (median 63, 87% females). RESULTS BMD was reduced at the femoral neck (P < 0.001) and forearm (P < 0.001), but normal at the lumbar spine (P = 0.11). Levels of biochemical bone markers were associated with high plasma PTH, high plasma 1,25(OH)(2)D and low plasma levels of 25OHD. Moreover, low plasma 25OHD was associated with low levels of BMD at the femoral neck (r(p) = 0.23), the forearm (r(p) = 0.19) and the whole body (r(p) = 0.30), whereas plasma 1,25(OH)(2)D was inversely associated with BMD at all regional sites and the whole body. Plasma PTH only showed an inverse association with BMD at the forearm (r(p) = -0.21). No association was observed between biochemical variables and prevalent spinal fractures, all peripheral fractures or osteoporotic peripheral fractures. The annual increase in spinal BMD after surgery was positively associated with preoperative plasma PTH (r(p) = 0.40), whereas the annual increase in whole body BMD was inversely associated with plasma 25OHD (r(p) = -0.32). No change in BMD at the femoral neck and forearm was observed 1 year after surgery. CONCLUSION Low vitamin D status and high plasma 1,25(OH)(2)D are associated with increased bone turnover and decreased BMD in patients with PHPT.
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Affiliation(s)
- B Moosgaard
- Aarhus Bone and Mineral Research Group: Department of Endocrinology and Metabolism C, Aarhus University Hospital, DK 8000 Aarhus C, Denmark.
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