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Glaberson W, Seeherunvong W, Gaynor JJ, Katsoufis C, Defreitas M, Bao Y, Freundlich M, Ciancio G, Abitbol C, Chandar J. Determinants of hyperparathyroidism in children after kidney transplantation. Clin Transplant 2024; 38:e15284. [PMID: 38483311 DOI: 10.1111/ctr.15284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 02/02/2024] [Accepted: 02/22/2024] [Indexed: 04/20/2024]
Abstract
INTRODUCTION Hyperparathyroidism (HPT) can contribute to metabolic bone disease following kidney transplantation. We evaluated post-transplant trends in intact parathyroid hormone (iPTH) and determined predictors of HPT in pediatric kidney transplant (KTx) recipients. METHODS In this single-center study, retrospective data were collected on 88 children from 2013 to 2019. Data collected included dialysis vintage, biochemical parameters, post-transplant trends in iPTH, 25(OH)Vitamin D levels and estimated glomerular filtration rate (eGFR ml/min/1.73 m2 ). Pre-transplant treatment for HPT was quantified with a Treatment Burden score (TB, score range: 0-100). After log-transforming skewed variables (iPTH and eGFR), multivariable linear regression was performed to determine predictors of log {iPTH} at 6 and 36 months (mo) post-transplant. RESULTS Median age was 12.8 (range: 1.9-20.5) years, and dialysis vintage was 11.2 (range: 0.0-112.9) months. The majority were of Hispanic and African Ancestry (77.3%). Median post-transplant iPTH was 69.5 (range: 1.8-306.8) pg/ml at 6 mo with a gradual downward trend to 59.0 (range: 28.0-445.0) pg/ml at 36 mo. Significant multivariable predictors of higher log {iPTH} post-transplant included longer dialysis vintage, higher TB, and lower log{eGFR} at 6 mo, and higher TB, lower log{eGFR}, and deceased donor transplant at 36 mo. CONCLUSIONS Recognition of risk factors for HPT and monitoring iPTH post-transplant may facilitate timely interventions to mitigate cardiovascular and bone disease in pediatric KTx recipients. KEY MESSAGE Describe serial trends in intact PTH after kidney transplantation. Pre- and post-transplant factors that contribute to persistence or re-occurrence of hyperparathyroidism after kidney transplantation in children include longer dialysis vintage, high pre-transplant treatment burden and decreased post-transplant GFR. Recognition of these factors, and monitoring intact PTH after kidney transplantation, could facilitate timely interventions to mitigate cardiovascular and bone disease in children.
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Affiliation(s)
- Wendy Glaberson
- Department of Pediatrics, Division of Pediatric Nephrology, University of Miami Miller School of Medicine (and the Miami Transplant Institute), Miami, Florida, USA
| | - Wacharee Seeherunvong
- Department of Pediatrics, Division of Pediatric Nephrology, University of Miami Miller School of Medicine (and the Miami Transplant Institute), Miami, Florida, USA
| | - Jeffrey J Gaynor
- Department of Surgery, Division of Transplantation, University of Miami Miller School of Medicine (and the Miami Transplant Institute), Miami, Florida, USA
| | - Chryso Katsoufis
- Department of Pediatrics, Division of Pediatric Nephrology, University of Miami Miller School of Medicine (and the Miami Transplant Institute), Miami, Florida, USA
| | - Marissa Defreitas
- Department of Pediatrics, Division of Pediatric Nephrology, University of Miami Miller School of Medicine (and the Miami Transplant Institute), Miami, Florida, USA
- Department of Surgery, Division of Transplantation, University of Miami Miller School of Medicine (and the Miami Transplant Institute), Miami, Florida, USA
| | - Yong Bao
- Department of Pediatrics, Division of Pediatric Endocrinology, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Michael Freundlich
- Department of Pediatrics, Division of Pediatric Nephrology, University of Miami Miller School of Medicine (and the Miami Transplant Institute), Miami, Florida, USA
| | - Gaetano Ciancio
- Department of Surgery, Division of Transplantation, University of Miami Miller School of Medicine (and the Miami Transplant Institute), Miami, Florida, USA
| | - Carolyn Abitbol
- Department of Pediatrics, Division of Pediatric Nephrology, University of Miami Miller School of Medicine (and the Miami Transplant Institute), Miami, Florida, USA
| | - Jayanthi Chandar
- Department of Pediatrics, Division of Pediatric Nephrology, University of Miami Miller School of Medicine (and the Miami Transplant Institute), Miami, Florida, USA
- Department of Surgery, Division of Transplantation, University of Miami Miller School of Medicine (and the Miami Transplant Institute), Miami, Florida, USA
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Li X, Gu H, Wu X. A commentary on 'The role of rapid intraoperative parathyroid hormone (ioPTH) assay in determining outcome of parathyroidectomy in primary hyperparathyroidism: A systematic review and meta-analysis'. Int J Surg 2023; 109:4380-4381. [PMID: 37702567 PMCID: PMC10720845 DOI: 10.1097/js9.0000000000000716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 08/19/2023] [Indexed: 09/14/2023]
Affiliation(s)
- Xin Li
- Department of Internal Medicine, Yuyao Hospital of Traditional Chinese Medicine
| | - Hongping Gu
- Department of Internal Medicine, Yuyao Hospital of Traditional Chinese Medicine
| | - Xiaolin Wu
- Department of Oncology, Shaoxing Shangyu People’s Hospital, Zhejiang, People’s Republic of China
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Hashim SM, Tuan Ismail TS, Che Soh NAA, Mat MC, Rapiah ZF, Shafii N, Kassim NK, Yaacob NM. Agreement of Parathyroid Hormone Status Measured by Intact and Biointact Parathyroid Hormone Assays among Chronic Kidney Disease Patients and Its Correlation with Bone Turnover Parameters. Malays J Med Sci 2023; 30:69-82. [PMID: 37102048 PMCID: PMC10125231 DOI: 10.21315/mjms2023.30.2.6] [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] [Received: 02/20/2022] [Accepted: 07/31/2022] [Indexed: 04/28/2023] Open
Abstract
Background This study aimed to determine the agreement between intact parathyroid hormone (iPTH) and biointact parathyroid hormone (bio-PTH) assays and to correlate them with bone markers. Methods This cross-sectional study included 180 patients with chronic kidney disease (CKD) stages 3b, 4 and 5D. We measured their iPTH, bio-PTH, 25-hydroxyvitaminD (25(OH)D), C-terminal telopeptide collagen (CTX), procollagen 1 intact N-terminal propeptide (P1NP), calcium, phosphate and alkaline phosphatase (ALP). Results Higher iPTH than bio-PTH concentrations were seen in CKD stages 3b, 4 and 5D (58[62] versus 55[67] pg/mL, 94[85] versus 85[76] pg/mL and 378[481] versus 252[280] pg/mL, respectively). Both PTH assays showed good agreement among all the subjects, with an intraclass correlation coefficient of 0.832 (P-value < 0.001). The Passing-Bablok showed that the equation for the bio-PTH was PTH = 0.64 iPTH + 15.80, with r = 0.99. The Bland-Altman plots showed increased bias with an increasing PTH concentration. Both PTH assays showed a high positive correlation with CTX and P1NP, a moderate correlation with phosphate, a low correlation with ALP and calcium, and a negligible correlation with phosphate and 25(OH)D. Conclusion The iPTH and bio-PTH assays were in agreement, but their bias increased with the PTH concentration. The unacceptable large bias indicates that the two assays cannot be used interchangeably. They had a variable correlation with the bone parameters.
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Affiliation(s)
- Saidah Madihah Hashim
- Chemical Pathology Unit, Hospital Raja Perempuan Zainab II, Kelantan, Malaysia
- Department of Chemical Pathology, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
| | - Tuan Salwani Tuan Ismail
- Department of Chemical Pathology, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
| | - Noor Azlin Azraini Che Soh
- Department of Chemical Pathology, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
| | - Mahaya Che Mat
- Chemical Pathology Unit, Hospital Raja Perempuan Zainab II, Kelantan, Malaysia
| | - Zuad Firdaus Rapiah
- Nephrology Unit, Department of Medical, Hospital Raja Perempuan Zainab II, Kelantan, Malaysia
| | - Noorazliyana Shafii
- Department of Chemical Pathology, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
| | - Nur Karyatee Kassim
- Department of Chemical Pathology, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
- School of Dental Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
| | - Najib Majdi Yaacob
- Biostatistics and Research Methodology Unit, Universiti Sains Malaysia, Kelantan, Malaysia
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Minieri M, Leoni BD, Bellincampi L, Bajo D, Agnoli A, De Angelis AM, Pieri M, Equitani F, Rossi V, Valente F, Pignalosa S, Terrinoni A, Bernardini S. Serum iPTH range in a reference population: From an integrated approach to vitamin D prevalence impact evaluation. Clin Chim Acta 2021; 521:1-8. [PMID: 34111419 DOI: 10.1016/j.cca.2021.06.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 05/31/2021] [Accepted: 06/01/2021] [Indexed: 01/24/2023]
Abstract
BACKGROUND The iPTH upper reference limit (URL) reported by our laboratory provider (Abbott Laboratories) at Tor Vergata University Hospital was evaluated by internal verification procedures as not representative of our population and resulting as underestimated. In this study, a new reference interval has been investigated and established by comparing a direct and an indirect method based on a statistical reduction from results stored in the laboratory database. METHODS For reference interval calculation from the healthy population, we analyzed a cohort of 100 blood donors (84% males and 16% females) screened with no bone-related and malabsorption diseases. We analyzed a cohort of 495 patients retrieved from more than 800 iPTH results by excluding subjects with pathological measurement for calcium, phosphorus, and creatinine for the reference interval evaluation. Patients with vitamin D results were included in the analysis. Vitamin D sufficiency status during the period from January to September 2020 was also evaluated by investigating 3,050 patients. RESULTS The iPTH reference interval of a healthy blood donor population was measured as 25.2-109.1 pg/mL (2.7-11.6 pmol/L) at 2.5 and 97.5 distribution percentile. The iPTH reference interval from data stored in the laboratory database was 19.3-112.5 pg/mL (2.0-11.9 pmol/L). Furthermore, 60% of the whole population had prevalently insufficient vitamin D concentration (<30 ng/dL; <75 nmol/L). The impact of vitamin D concentration on the iPTH reference interval was measured for insufficient vitamin D (<30 ng/dL; <75 nmol/L) as 15.2-127.7 pg/mL (1.6-13.5 pmol/L), desirable vitamin D (30-40 ng/ml; 75-100 nmol/L) as 25.6-105 pg/mL (2.7-10.7 pmol/L) and optimal vitamin D (>40 ng/ml; >100 nmol/L) as 26.2-89.2 pg/mL (2.8-9.4 pmol/L), respectively. CONCLUSIONS The URL reported in manufacturer datasheets likely refers to a normal population with non-pathological vitamin D levels. On the contrary, the considered population was mostly vitamin D insufficient, resulting in a URL shift. On this basis, we suggest describing in medical reports the iPTH range for vitamin D deficiency for diagnosis of primary hyperparathyroidism even when a specific vitamin D request is lacking. On the other hand, reporting optimal vitamin D-based iPTH reference interval could be clinically relevant in supplemented patients as a marker of treatment efficacy.
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Affiliation(s)
- Marilena Minieri
- Department of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy; Unit of Laboratory Medicine, Tor Vergata University Hospital, Rome, Italy.
| | | | | | - Daniela Bajo
- Unit of Laboratory Medicine, Tor Vergata University Hospital, Rome, Italy
| | - Alessia Agnoli
- Unit of Laboratory Medicine, Tor Vergata University Hospital, Rome, Italy
| | | | - Massimo Pieri
- Department of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Francesco Equitani
- Department of Transfusion Medicine, Santa Maria Goretti Hospital, AUSL Latina, Italy
| | | | | | | | - Alessandro Terrinoni
- Department of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Sergio Bernardini
- Department of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy; Unit of Laboratory Medicine, Tor Vergata University Hospital, Rome, Italy
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Cavalier E, Vasikaran S, Bhattoa HP, Heijboer AC, Makris K, Ulmer CZ. The path to the standardization of PTH: Is this a realistic possibility? a position paper of the IFCC C-BM. Clin Chim Acta 2021; 515:44-51. [PMID: 33412144 DOI: 10.1016/j.cca.2020.12.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/07/2020] [Accepted: 12/18/2020] [Indexed: 11/18/2022]
Abstract
Parathyroid hormone (PTH) determination is of greatest importance for patients suffering from parathyroid gland disorders and for the follow-up of bone turnover in patients suffering from chronic kidney disease (CKD). Two generations of PTH assays are simultaneously present on the market for PTH quantification. As these assays are not yet standardized, this results in a significant level of confusion in the care of CKD patients. One key objective of the IFCC Committee for Bone Metabolism is to improve this situation. In this position paper, we will highlight the current state of PTH testing and propose a pathway to ultimately overcome issues resulting from PTH assay variability.
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Affiliation(s)
- Etienne Cavalier
- Department of Clinical Chemistry, University of Liège, CHU de Liège, Domaine du Sart-Tilman, B-4000 Liège, Belgium.
| | - Samuel Vasikaran
- PathWest Laboratory Medicine, Fiona Stanley Hospital, Murdoch, WA, Australia
| | - Harjit P Bhattoa
- Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Debrecen Hungary
| | - Annemieke C Heijboer
- Department of Clinical Chemistry, Endocrine Laboratory, Amsterdam Gastroenterology & Metabolism, Vrije Universiteit Amsterdam and University of Amsterdam, Amsterdam UMC, Amsterdam, Netherlands
| | - Konstantinos Makris
- Clinical Biochemistry Department, KAT General Hospital, 14561 Athens, Greece; Laboratory for Research of the Musculoskeletal System "Th. Garofalidis", Medical School, University of Athens, Athens, Greece
| | - Candice Z Ulmer
- Clinical Chemistry Branch, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Buford, Atlanta, GA, USA
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Malla P, Chen GC, Liao HP, Liu CH, Wu WC. Label-free parathyroid hormone immunosensor using nanocomposite modified carbon electrode. J Electroanal Chem (Lausanne) 2021. [DOI: 10.1016/j.jelechem.2020.114917] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Chen GC, Liu CH, Wu WC. Electrochemical immunosensor for serum parathyroid hormone using voltammetric techniques and a portable simulator. Anal Chim Acta 2021; 1143:84-92. [DOI: 10.1016/j.aca.2020.11.045] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/25/2020] [Accepted: 11/27/2020] [Indexed: 01/10/2023]
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Wójtowicz M, Piechota W, Wańkowicz Z, Smoszna J, Niemczyk S. Comparison of Second- and Third-Generation Parathyroid Hormone Test Results in Patients with Chronic Kidney Disease. Med Sci Monit 2020; 26:e928301. [PMID: 33361742 PMCID: PMC7771203 DOI: 10.12659/msm.928301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND In patients with chronic kidney disease (CKD), secondary hyperparathyroidism is assessed by measuring serum parathyroid hormone (PTH) levels. Well-established, recommended, second-generation intact parathyroid hormone (iPTH) tests are typical; rarely are more recent third-generation PTH 1-84 assays used. The agreement between results of the 2 tests in patients with CKD has not been sufficiently defined. MATERIAL AND METHODS This study aimed to compare Roche second- and third-generation PTH assays by establishing a quantitative relationship between the results of assays in patients with CKD and assessing degree of their correlation with kidney function and calcium-phosphate and bone metabolism parameters. In 205 patients with stages 3 to 5D CKD and 30 healthy controls, we measured levels of iPTH and PTH (1-84), creatinine, urea, cystatin C, calcium, inorganic phosphate, magnesium, alkaline phosphatase, bone alkaline phosphatase, osteocalcin, and ß-CrossLaps. RESULTS The third-generation PTH assay results were more than 40% lower than those obtained with the second-generation test in patients undergoing dialysis and approximately 30% lower in patients in the pre-dialysis period. PTH concentrations determined with both assays were almost to the same extent correlated with calcium-phosphate and bone metabolism parameters, and renal function indices. Formulas have been developed enabling 2-way conversion of PTH results determined with both the second- and third-generation PTH assays: For dialyzed patients, PTH (1-84)=0.5181iPTH+18.0595. Serum osteocalcin, ß-CrossLaps, and total calcium were independent predictors of PTH levels. CONCLUSIONS Correcting for the established quantitative differences, the second-and third-generation PTH tests can be used interchangeably, given the almost identical pathophysiological correlations of their results with calcium-phosphate and bone metabolism parameters.
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Affiliation(s)
- Magdalena Wójtowicz
- Department of Laboratory Diagnostics, Military Institute of Medicine, Warsaw, Poland
| | - Wiesław Piechota
- Department of Laboratory Diagnostics, Military Institute of Medicine, Warsaw, Poland
| | - Zofia Wańkowicz
- Department of Internal Medicine, Nephrology and Dialysis, Military Institute of Medicine, Warsaw, Poland
| | - Jerzy Smoszna
- Department of Internal Medicine, Nephrology and Dialysis, Military Institute of Medicine, Warsaw, Poland
| | - Stanisław Niemczyk
- Department of Internal Medicine, Nephrology and Dialysis, Military Institute of Medicine, Warsaw, Poland
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Lang BHH, Fung MMH. Intraoperative parathyroid hormone (IOPTH) assay might be better than the second-generation assay in parathyroidectomy for primary hyperparathyroidism. Surgery 2020; 169:109-113. [PMID: 32402543 DOI: 10.1016/j.surg.2020.03.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 02/27/2020] [Accepted: 03/10/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND It is unclear whether the third-generation intraoperative parathyroid hormone assay can improve surgical outcomes over second-generation assay in primary hyperparathyroidism. We aimed to compare the rate of decrease and diagnostic accuracy between the two assays after parathyroid adenoma excision. METHODS Consecutive patients undergoing parathyroidectomy with intraoperative parathyroid hormone were analyzed. Blood was drawn before and 10 minutes and 20 minutes after excision of the adenoma. The same blood sample was run simultaneously in the second-generation assays (Elecsys PTH STAT) and third-generation assays (Elecsys 1-84 PTH). Biochemical cure meant >50% intraoperative parathyroid hormone decrease at 10 minutes. Cure meant normocalcemia 6 months after operation. RESULTS Relative to the second-generation assay, the value of the intraoperative parathyroid hormone level was less in the third-generation assay before excision (P < .001), at 10 minutes (P < .001), and at 20 minutes (P < .001). The intraoperative parathyroid hormone rate of decrease and the proportion of normalized post-excision intraoperative parathyroid hormone were greater in the third-generation assay (P < .001), but the prediction accuracy appeared similar between the 2 (91.5% vs 91.0%). Patients with worse renal function (estimated glomerular filtration rate <80mL/min/1.73m2) had a slower intraoperative parathyroid hormone decrease in the second-generation but not in the third-generation assay. CONCLUSION Despite comparable accuracy between the two generations of assay, the third-generation assay might be better than the second-generation assay because of the more rapid decrease in the intraoperative parathyroid hormone and a greater percentage of normalized intraoperative parathyroid hormone, regardless of baseline renal function.
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Affiliation(s)
- Brian Hung-Hin Lang
- Division of Endocrine Surgery, Department of Surgery, University of Hong Kong, Hong Kong SAR, China.
| | - Matrix Man Him Fung
- Division of Endocrine Surgery, Department of Surgery, Queen Mary Hospital, Hong Kong SAR, China
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Censi S, Iacobone M, Simmini S, Manso J, Franceschet G, Plebani M, Frigo AC, Zaninotto M, Torresan F, De Silvestro G, Scaroni C, Mian C, Camozzi V. PTH: Redefining Reference Ranges in a Healthy Population-The Role of Interfering Factors and the Type of Laboratory Assay. Int J Endocrinol 2020; 2020:1053719. [PMID: 32148482 PMCID: PMC7054804 DOI: 10.1155/2020/1053719] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 01/23/2020] [Indexed: 01/22/2023] Open
Abstract
UNLABELLED Introduction. Parathyroid hormone (PTH) is a linear peptide constituted by 84 amino acids and active in its 1-84 form, but a wide range of PTH forms produced by its post-transcriptional modifications are present in blood. Many assays with different specificities are commercially available. The aim of our study was to compare a 2nd and 3rd generation in healthy population in order to better define the reference range in the healthy population residing in our region. Materials and Methods. 108 subjects (53 females and 55 males) referring to the transfusion donor were enrolled in the study centre in April 2016 and underwent PTH levels measurements with a 3rd generation kit (chemiluminescent immunoassay DiaSorin Liaison) and with a 2nd generation kit (immunoradiometric assay Total Intact PTH Assay (Coated Tube), Scantibodies). Also calcium, phosphate, creatinine, and 25OHD3 were measured. A questionnaire on lifestyle and dietary habits was obtained. RESULTS The median PTH values obtained with the 2nd generation assay and the whole 3rd generation assay were 20.26 pg/ml and 23.11 pg/ml, respectively. Bland-Altman method showed substantial concordance between the two PTH assays, although with an overestimation of the 3rd generation method over the 2nd generation method. There was no correlation between 3rd generation PTH and 25OHD3 and creatinine. Calcium was negatively correlated with PTH only when measured with 3rd generation kit. CONCLUSIONS On the basis of our data, obtained from healthy subjects, we can conclude that the reference range used by our laboratory was too narrow and was necessary to reestablish normal ranges according to our population. This is useful to avoid hyperparathyroidism misdiagnosis.
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Affiliation(s)
- Simona Censi
- Endocrinology Unit, Department of Medicine (DIMED), University of Padua, Padua, Italy
| | - Maurizio Iacobone
- Endocrine Surgery Unit, Department of Surgery, Oncology and Gastroenterology (DiSCOG), University of Padua, Padua, Italy
| | - Stefano Simmini
- Endocrinology Unit, Department of Medicine (DIMED), University of Padua, Padua, Italy
| | - Jacopo Manso
- Endocrinology Unit, Department of Medicine (DIMED), University of Padua, Padua, Italy
| | - Giulio Franceschet
- Endocrinology Unit, Department of Medicine (DIMED), University of Padua, Padua, Italy
| | - Mario Plebani
- Laboratory Medicine, Department of Medicine (DIMED), University of Padua, Padua, Italy
| | - Anna Chiara Frigo
- Department of Cardiac, Thoracic and Vascular Sciences, Biostatistics, Epidemiology and Public Health Unit, University of Padua, Padua, Italy
| | - Martina Zaninotto
- Laboratory Medicine, Department of Medicine (DIMED), University of Padua, Padua, Italy
| | - Francesca Torresan
- Endocrine Surgery Unit, Department of Surgery, Oncology and Gastroenterology (DiSCOG), University of Padua, Padua, Italy
| | | | - Carla Scaroni
- Endocrinology Unit, Department of Medicine (DIMED), University of Padua, Padua, Italy
| | - Caterina Mian
- Endocrinology Unit, Department of Medicine (DIMED), University of Padua, Padua, Italy
| | - Valentina Camozzi
- Endocrinology Unit, Department of Medicine (DIMED), University of Padua, Padua, Italy
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Dupuy AM, Bargnoux AS, Morena M, Lauret E, Souberbielle JC, Cavalier E, Cristol JP. Moving from the second to the third generation Roche PTH assays: what are the consequences for clinical practice? Clin Chem Lab Med 2018; 57:244-249. [PMID: 30183664 DOI: 10.1515/cclm-2018-0300] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 07/06/2018] [Indexed: 11/15/2022]
Abstract
Background The determination of parathyroid hormone (PTH) is essential for exploring phosphocalcic disorders especially in patients with renal failure. At present, second or third generation PTH assays are available on the market from Roche Diagnostics as well as from others companies but the lack of standardization has complicated the interpretation. Methods We wanted to assess the clinical impact by measuring the PTH levels with the two generations concomitantly on different groups of populations including 46 healthy, 103 pre-dialyzed and 73 hemodialyzed (HD) patients. Results In healthy subjects, the PTH concentrations were not different whatever the generation used, whereas beyond 200 pg/mL, we reported an overestimation of the second generation PTH. In patients with chronic kidney disease (CKD) stage 3-5 the observed differences between the two generations increase with increasing PTH levels and decreasing glomerular filtration rate (GFR). Classification according to the kidney disease: improving global outcomes (KDIGO) revealed a high percentage of discordant results between the two generations (κ coefficient <0.20). These discrepancies are clinically relevant as PTH levels remain the cornerstone for diagnosis and treatment of the CKD-mineral and bone disorder (CKD-MBD). Conclusions The introduction of a new PTH assay generation in clinical practice should be carried out with caution.
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Affiliation(s)
- Anne Marie Dupuy
- Laboratoire de Biochimie et Hormonologie, CHU Montpellier, University Montpellier 1, Montpellier, France
| | - Anne Sophie Bargnoux
- Laboratoire de Biochimie et Hormonologie, CHU de Montpellier, PhyMedExp, University of Montpellier, INSERM U1046, CNRS UMR 9214, Montpellier, France
| | - Marion Morena
- Laboratoire de Biochimie et Hormonologie, CHU de Montpellier, PhyMedExp, University of Montpellier, INSERM U1046, CNRS UMR 9214, Montpellier, France
| | - Emilie Lauret
- Laboratoire de Biochimie et Hormonologie, CHU Montpellier, University Montpellier 1, Montpellier, France
| | - Jean Claude Souberbielle
- Service d'explorations fonctionnelles, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris, Université René Descartes (Paris V), Paris, France
| | - Etienne Cavalier
- Département de Chimie Clinique, CHU Liège, Université de Liège, Liège, Belgium
| | - Jean Paul Cristol
- Laboratoire de Biochimie et Hormonologie, CHU Montpellier, University Montpellier 1, 371 Avenue Doyen Gaston Giraud, Montpellier 34295, France
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Soliman M, Hassan W, Yaseen M, Rao M, Sawaya BP, El-Husseini A. PTH assays in dialysis patients: Practical considerations. Semin Dial 2018; 32:9-14. [PMID: 30168196 DOI: 10.1111/sdi.12743] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Parathyroid hormone (PTH) 1-84 is the main biologically active hormone produced by the parathyroid cells. Circulating PTH molecules include the whole PTH 1-84 along with amino (N) and carboxyl (C) terminal fragments. While PTH is the best available noninvasive biomarker to assess bone turnover in dialysis patients, the biological roles of individual circulating PTH fragments are still not completely known. The understanding that there is an enormous variation in the target specificity of currently available PTH assays for different circulating forms of PTH has led to the evolution of assays from first to second then third generation. With a reduction in kidney function, there is a preferential increase in circulating C fragments and non-PTH 1-84 forms, resulting in a decrease in the ratio of PTH 1-84/non-PTH 1-84. However, there are also substantial differences in between-assay measurements, with several fold variations in results. Targets based on multiples of the upper limit of normal (ULN) should be used rather than PTH ranges using absolute iPTH values. To date, the second-generation PTH remains the most widely used assay. Current guidelines recommend following iPTH trends rather than absolute values. Herein, we highlight problems and challenges in PTH assays/measurements and their interpretations in dialysis patients.
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Affiliation(s)
- Mohanad Soliman
- Division of Nephrology, Bone and Mineral Metabolism, University of Kentucky, Lexington, Kentucky
| | - Waleed Hassan
- Division of Nephrology, Bone and Mineral Metabolism, University of Kentucky, Lexington, Kentucky
| | - Maria Yaseen
- Division of Nephrology, Bone and Mineral Metabolism, University of Kentucky, Lexington, Kentucky
| | - Madhumathi Rao
- Division of Nephrology, Bone and Mineral Metabolism, University of Kentucky, Lexington, Kentucky
| | - B Peter Sawaya
- Division of Nephrology, Bone and Mineral Metabolism, University of Kentucky, Lexington, Kentucky
| | - Amr El-Husseini
- Division of Nephrology, Bone and Mineral Metabolism, University of Kentucky, Lexington, Kentucky
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Kakuta T, Ishida M, Fukagawa M. Critical Governance Issue of Parathyroid Hormone Assays and its Selection in the Management of Chronic Kidney Disease Mineral and Bone Disorders. Ther Apher Dial 2018; 22:220-228. [PMID: 29781225 DOI: 10.1111/1744-9987.12690] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 03/19/2018] [Accepted: 03/23/2018] [Indexed: 11/28/2022]
Abstract
Measurement of circulating parathyroid hormone (PTH) levels is essential for optimal management of mineral and bone disorders (MBD) in chronic kidney disease (CKD) patients. There are two major types of PTH assays currently in use: intact parathyroid hormone (i-PTH) and whole PTH (w-PTH) assays. The i-PTH assay is the current standard, and considerable information regarding the management of CKD-MBD has been obtained with this method. However, several limitations have been found with the i-PTH assay. One limitation is that i-PTH assay also measures fragments other than full-length PTH (1-84). Another limitation is the existence of multiple readout methods of the i-PTH assay. The w-PTH assay is theoretically ideal because it exclusively detects full-length PTH (1-84). However, clinical data proving the advantages of w-PTH measurement are not sufficient. For uremic patients, Kidney Disease Improving Global Outcomes suggest that PTH levels should be maintained within approximately two to nine times the upper normal limit of the i-PTH assays. The most critical issue in the evaluation of PTH levels is the lack of definitive PTH assay method. Evidence-based recommendations on clinical management goals of PTH are warranted.
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Affiliation(s)
- Takatoshi Kakuta
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University Hachioji Hospital, Tokyo, Japan
| | - Mari Ishida
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University Hachioji Hospital, Tokyo, Japan
| | - Masafumi Fukagawa
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, Isehara, Japan
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Einbinder Y, Benchetrit S, Golan E, Zitman-Gal T. Comparison of Intact PTH and Bio-Intact PTH Assays Among Non-Dialysis Dependent Chronic Kidney Disease Patients. Ann Lab Med 2018. [PMID: 28643486 PMCID: PMC5500736 DOI: 10.3343/alm.2017.37.5.381] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The third-generation bio-intact parathyroid hormone (PTH) (1-84) assay was designed to overcome problems associated with the detection of C-terminal fragments by the second-generation intact PTH assay. The two assays have been compared primarily among dialysis populations. The present study evaluated the correlations and differences between these two PTH assays among patients with chronic kidney disease (CKD) stages 3 to 5 not yet on dialysis. METHODS Blood samples were collected from 98 patients with CKD stages 3 to 5. PTH concentrations were measured simultaneously by using the second-generation - PTH intact-STAT and third-generation bio-intact 1-84 PTH assays. Other serum biomarkers of bone mineral disorders were also assessed. CKD stage was calculated by using the CKD-Epidemiology Collaboration (EPI) formula. RESULTS Serum bio-intact PTH concentrations were strongly correlated but significantly lower than the intact PTH concentrations (r=0.963, P<0.0001). This finding was consistent among CKD stages 3 to 5. PTH concentrations by both assays (intact and bio-intact PTH) positively correlated with urea (r=0.523, r=0.504; P=0.002, respectively), phosphorus (r=0.532, r=0.521; P<0.0001, respectively) and negatively correlated with blood calcium (r=-0.435, r=-0.476; P<0.0001, respectively), 25(OH) vitamin D, (r=-0.319, r=-0.353; respectively, P<0.0001) and the estimated glomerular filtration rate (r=-0.717, r=-0.688; P<0.0001, respectively). CONCLUSIONS Among patients with CKD stages 3 to 5 not on dialysis, the bio-intact PTH assay detected significantly lower PTH concentrations compared with intact PTH assay. Additional studies that correlate the diagnosis and management of CKD mineral and bone disorders with bone histomorphometric findings are needed to determine whether bio-intact PTH assay results are better surrogate markers in these early stages of CKD.
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Affiliation(s)
- Yael Einbinder
- Department of Nephrology and Hypertension, Meir Medical Center, Kfar Saba, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Sydney Benchetrit
- Department of Nephrology and Hypertension, Meir Medical Center, Kfar Saba, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Eliezer Golan
- Department of Nephrology and Hypertension, Meir Medical Center, Kfar Saba, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Tali Zitman-Gal
- Department of Nephrology and Hypertension, Meir Medical Center, Kfar Saba, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
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Jenabi A, Jabbari M, Ziaie H. Comparing the values of intact parathormone and 1– 84 PTH
to predict hyperparathyroidism in hemodialysis patients. J Nephropathol 2017; 6:248-253. [PMID: 28975108 PMCID: PMC5607990 DOI: 10.15171/jnp.2017.40] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Accepted: 03/25/2017] [Indexed: 11/25/2022] Open
Abstract
Background:
Secondary hyperparathyroidism (SHPT) is a common complication of chronic
kidney disease (CKD) leading high mortality and even long-term morbidity. SHPT is
manifested by elevation of parathyroid hormone (PTH) and accurate determining the
level of serum PTH is very essential for early diagnosis of SHPT secondary to CKD. It is
very important to match the values obtained for intact parathormone (iPTH) and 1– 84
PTH with the minimized measurement bias.
Objectives:
The present study aimed to first determine the agreement value between the
iPTH and 1– 84 PTH measures in patients with hyperparathyroidism secondary to endstage
renal disease under chronic hemodialysis. Then, we attempted to determine the best
cutoff values for these two measurements for detecting SHPT in such patients.
Patients and Methods:
This cross-sectional study was conducted on hemodialysis patients.
The value of study biomarkers including iPTH and 1– 84 PTH was assessed.
Results:
A strong positive association was revealed between the two indicators of iPTH and
1-84 PTH (r = 0.800, P < 0.001). The linear association between these two parameters is
independent to baseline characteristics including gender, age, body mass index, and medical
history. Among all biochemical elements, the value of 1-84 PTH was only associated with
serum calcium level negatively (r = -0.267, P = 0.027) and alkaline phosphatase positively
(r = 0.359, P = 0.003). Considering iPTH as the reference and according to the area under
the ROC curve (AUC), 1-84 PTH had high value to predict hyperparathyroidism (AUC =
0.926, P < 0.001). The best cutoff point for 1-84 PTH to discriminate hyperparathyroidism
from normal condition was 60 yielding a sensitivity of 92.3% and a specificity of 79.1%.
Among other baseline laboratory parameters, only alkaline phosphatase had an acceptable
value for diagnosing hyperparathyroidism (AUC = 0.731, P = 0.001).
Conclusions:
The measurement of both iPTH and 1-84 PTH is valuable for predicting
hyperparathyroidism secondary to CKD, but according to lower cost and comparableeffectiveness
of iPTH measurement, this assay may be comparable to 1-84 PTH to predict
this consequence.
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McCarthy JT, El-Azhary RA, Patzelt MT, Weaver AL, Albright RC, Bridges AD, Claus PL, Davis MDP, Dillon JJ, El-Zoghby ZM, Hickson LJ, Kumar R, McBane RD, McCarthy-Fruin KAM, McEvoy MT, Pittelkow MR, Wetter DA, Williams AW. Survival, Risk Factors, and Effect of Treatment in 101 Patients With Calciphylaxis. Mayo Clin Proc 2016; 91:1384-1394. [PMID: 27712637 DOI: 10.1016/j.mayocp.2016.06.025] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 06/18/2016] [Accepted: 06/21/2016] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To report on the survival and the associations of treatments upon survival of patients with calciphylaxis seen at a single center. PATIENTS AND METHODS Using the International Classification of Diseases, Ninth Revision diagnosis code of 275.49 and the keyword "calciphylaxis" in the dismissal narrative, we retrospectively identified 101 patients with calciphylaxis seen at our institution between January 1, 1999, through September 20, 2014, using a predefined, consensus-developed classification scheme. RESULTS The average age of patients was 60 years: 81 (80.2%) were women; 68 (68.0%) were obese; 19 (18.8%) had stage 0 to 2 chronic kidney disease (CKD), 19 (18.9%) had stage 3 or 4 CKD; 63 (62.4%) had stage 5 or 5D (dialysis) CKD. Seventy-five patients died during follow-up. Six-month survival was 57%. Lack of surgical debridement was associated with insignificantly lower 6-month survival (hazard ratio [HR]=1.99; 95% CI, 0.96-4.15; P=.07) and significantly poorer survival for the entire duration of follow-up (HR=1.98; 95% CI, 1.15-3.41; P=.01), which was most pronounced in stage 5 or 5D CKD (HR=1.91; 95% CI, 1.03-3.56; P=.04). Among patients with stage 5/5D CKD, subtotal parathyroidectomy (performed only in patients with hyperparathyroidism) was associated with better 6-month (HR=0.12; 95% CI, 0.02-0.90; P=.04) and overall survival (HR= 0.37; 95% CI, 0.15-0.87; P=.02). CONCLUSION Calciphylaxis is associated with a high mortality rate. Significantly effective treatments included surgical debridement and subtotal parathyroidectomy in patients with stage 5/5D CKD with hyperparathyroidism. Treatments with tissue-plasminogen activator, sodium thiosulfate, and hyperbaric oxygen therapy were not associated with higher mortality.
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Affiliation(s)
- James T McCarthy
- Department of Medicine, Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN.
| | | | - Michelle T Patzelt
- Mayo Medical School, Mayo Graduate School of Medicine, Mayo Clinic, Rochester, MN
| | - Amy L Weaver
- Department of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN
| | - Robert C Albright
- Department of Medicine, Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN
| | | | - Paul L Claus
- Department of Medicine, Division of Hyperbaric Medicine in Preventive, Occupational and Aerospace Medicine, Mayo Clinic, Rochester, MN
| | | | - John J Dillon
- Department of Medicine, Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN
| | - Ziad M El-Zoghby
- Department of Medicine, Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN
| | - LaTonya J Hickson
- Department of Medicine, Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN
| | - Rajiv Kumar
- Department of Medicine, Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN
| | - Robert D McBane
- Department of Cardiovascular Disease, Mayo Clinic, Rochester, MN
| | | | | | | | | | - Amy W Williams
- Department of Medicine, Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN
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Tønnesen R, Schwarz P, Hovind PH, Jensen LT. Physical exercise associated with improved BMD independently of sex and vitamin D levels in young adults. Eur J Appl Physiol 2016; 116:1297-304. [PMID: 27146169 PMCID: PMC4911375 DOI: 10.1007/s00421-016-3383-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 04/28/2016] [Indexed: 02/02/2023]
Abstract
Purpose Young men and women accrue the majority of their bone mass in their teens and twenties, where their bone mass peaks (PBM), yet little is known about the roles of physical exercise, vitamin D levels and bone mineral density (BMD) near PBM. Methods To comparatively examine the effect of physical exercise and two vitamin D levels (insufficient s-25[OH]D <50 nmol/L and sufficient s-25[OH]D >80 nmol/L) on the BMD measured at the femoral neck, total hip (bilaterally) and the lumbar spine (L2–L4) in male and female participants approaching PBM. Results The insufficient s-25[OH]D group, median age 21.6 (19.8–22.8) years, and BMI 24.2 ± 5.0 kg/m2 had BMD 0.10 (0.03, 0.17) g/cm2 (p = 0.008) lower at all DXA-scan sites compared to the sufficient s-25[OH]D group, median age 19.5 (19.0–22.3) years, and BMI of 22.6 ± 1.8 kg/m2. Exercise was positively associated with the BMD at all DXA-scan sites (ptrend = 0.0001) and with equal benefit; there was no interaction between exercise and the DXA-scan site (p = 0.09). The male participants did not have a systematically higher BMD than the female participants for all scan sites; only for hips total and femoral neck bilaterally, while it was equal at the lumbar spine. Conclusion The BMD in young healthy adults is associated with physical exercise, independent of sex and s-25[OH]D status. A sufficient s-25[OH]D status was systematically associated with a higher BMD for all levels of exercise. For both sexes and vitamin D levels exercise was equally positively associated with BMD.
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Affiliation(s)
- Rune Tønnesen
- Department of Clinical Physiology and Nuclear Medicine, Rigshospitalet, Nordre Ringvej 57, Glostrup, 2600, Copenhagen, Denmark.
| | - Peter Schwarz
- Department of Endocrinology PE and Research Centre of Ageing and Osteoporosis, Rigshospitalet, Copenhagen, Denmark
- Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Peter Hambak Hovind
- Department of Clinical Physiology and Nuclear Medicine, Rigshospitalet, Nordre Ringvej 57, Glostrup, 2600, Copenhagen, Denmark
| | - Lars Thorbjørn Jensen
- Department of Clinical Physiology and Nuclear Medicine, University Hospital of Herlev, Copenhagen, Denmark
- Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
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Lee S, Mannstadt M, Guo J, Kim SM, Yi HS, Khatri A, Dean T, Okazaki M, Gardella TJ, Jüppner H. A Homozygous [Cys25]PTH(1-84) Mutation That Impairs PTH/PTHrP Receptor Activation Defines a Novel Form of Hypoparathyroidism. J Bone Miner Res 2015; 30:1803-13. [PMID: 25891861 PMCID: PMC4580526 DOI: 10.1002/jbmr.2532] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 03/30/2015] [Accepted: 04/13/2015] [Indexed: 11/10/2022]
Abstract
Hypocalcemia and hyperphosphatemia are encountered in idiopathic hypoparathyroidism (IHP) and pseudohypoparathyroidism type Ib (PHP1B). In contrast to PHP1B, which is caused by resistance toward parathyroid hormone (PTH), the genetic defects leading to IHP impair production of this important regulator of mineral ion homeostasis. So far, only five PTH mutations were shown to cause IHP, each of which is located in the hormone's pre-pro leader segment and thus impair hormone secretion. In three siblings affected by IHP, we now identified a homozygous arginine-to-cysteine mutation at position 25 (R25C) of the mature PTH(1-84) polypeptide; heterozygous family members are healthy. Depending on the assay used for evaluating these patients, plasma PTH levels were either low or profoundly elevated, thus leading to ambiguities regarding the underlying diagnosis, namely IHP or PHP1B. Consistent with increased PTH levels, recombinant [Cys25]PTH(1-84) and wild-type PTH(1-84) were secreted equally well by transfected COS-7 cells. However, synthetic [Cys25]PTH(1-34) was found to have a lower binding affinity for the PTH receptor type-1 (PTH1R) than PTH(1-34) and consequently a lower efficiency for stimulating cAMP formation in cells expressing this receptor. Consistent with these in vitro findings, long-term infusion of [Cys25]PTH(1-34) resulted only in minimal calcemic and phosphaturic responses, despite readily detectable levels of [Cys25]PTH(1-34) in plasma. The mineral ion abnormalities observed in the three IHP patients are thus most likely caused by the inherited homozygous missense PTH mutation, which reduces bioactivity of the secreted hormone. Based on these findings, screening for PTH(1-84) mutations should be considered when clinical and laboratory findings are consistent with PHP1B, but GNAS methylation changes have been excluded. Differentiating between IHP and PHP1B has considerable implications for genetic counseling, therapy, and long-term outcome because treatment of IHP patients with inappropriately high doses of active vitamin D and calcium can contribute to development of nephrocalcinosis and chronic kidney disease.
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Affiliation(s)
- Sihoon Lee
- Department of Internal Medicine and Laboratory of Molecular Endocrinology, Gachon University School of Medicine, Incheon, South Korea
| | - Michael Mannstadt
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Jun Guo
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Seul Min Kim
- Department of Internal Medicine and Laboratory of Molecular Endocrinology, Gachon University School of Medicine, Incheon, South Korea
| | - Hyon-Seung Yi
- Department of Internal Medicine and Laboratory of Molecular Endocrinology, Gachon University School of Medicine, Incheon, South Korea
| | - Ashok Khatri
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Thomas Dean
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Makoto Okazaki
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Thomas J Gardella
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Harald Jüppner
- Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.,Pediatric Nephrology Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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Singh RJ, Hines JM, Lopez MF, Krastins B, Hoofnagle AN. Mass spectrometric immunoassay raises doubt for the existence of parathyroid hormone fragment 7-84. Clin Chem 2015; 61:558-60. [PMID: 25597752 DOI: 10.1373/clinchem.2014.235440] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Ravinder J Singh
- Department of Laboratory Medicine and Pathology Mayo Clinic Rochester, MN
| | - Jolaine M Hines
- Department of Laboratory Medicine and Pathology Mayo Clinic Rochester, MN
| | | | | | - Andrew N Hoofnagle
- Departments of Laboratory Medicine and Medicine University of Washington Seattle, WA
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A novel, ultrarapid parathyroid hormone assay to distinguish parathyroid from nonparathyroid tissue. Surgery 2014; 156:1638-43. [DOI: 10.1016/j.surg.2014.08.081] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 08/22/2014] [Indexed: 11/20/2022]
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