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Cavalcante LBCP, Brandão CMÁ, Chiamolera MI, Biscolla RPM, Junior JVL, de Sá Tavares Russo P, Morgado JPM, de Francischi Ferrer CMA, Vieira JGH. Big data-based parathyroid hormone (PTH) values emphasize need for age correction. J Endocrinol Invest 2023; 46:2525-2533. [PMID: 37286864 PMCID: PMC10632255 DOI: 10.1007/s40618-023-02107-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 04/30/2023] [Indexed: 06/09/2023]
Abstract
PURPOSE We aimed to study the relationship between aging and increased parathyroid hormone (PTH) values. METHODS We performed a retrospective cross-sectional study with data from patients who underwent outpatient PTH measurements performed by a second-generation electrochemiluminescence immunoassay. We included patients over 18 years of age with simultaneous PTH, calcium, and creatinine measurements and 25-OHD measured within 30 days. Patients with glomerular filtration rate < 60 mL/min/1.73 m2, altered calcemia, 25-OHD level < 20 ng/mL, PTH values > 100 pg/mL or using lithium, furosemide or antiresorptive therapy were excluded. Statistical analyses were performed using the RefineR method. RESULTS Our sample comprised 263,242 patients for the group with 25-OHD ≥ 20 ng/mL, that included 160,660 with 25-OHD ≥ 30 ng/mL. The difference in PTH values among age groups divided by decades was statistically significant (p < 0.0001), regardless of 25-OHD values, ≥ 20 or ≥ 30 ng/mL. In the group with 25-OHD ≥ 20 ng/mL and more than 60 years, the PTH values were 22.1-84.0 pg/mL, a different upper reference limit from the reference value recommended by the kit manufacturer. CONCLUSION We observed a correlation between aging and PTH increase, when measured by a second-generation immunoassay, regardless of vitamin D levels, if greater than 20 ng/mL, in normocalcemic individuals without renal dysfunction.
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Affiliation(s)
- L B C P Cavalcante
- Fleury Group, Rua Mato Grosso, 306, cj 408, Higienópolis, São Paulo, SP, 01239-040, Brazil.
| | - C M Á Brandão
- Fleury Group, Rua Mato Grosso, 306, cj 408, Higienópolis, São Paulo, SP, 01239-040, Brazil
| | - M I Chiamolera
- Fleury Group, Rua Mato Grosso, 306, cj 408, Higienópolis, São Paulo, SP, 01239-040, Brazil
| | - R P M Biscolla
- Fleury Group, Rua Mato Grosso, 306, cj 408, Higienópolis, São Paulo, SP, 01239-040, Brazil
| | - J V L Junior
- Fleury Group, Rua Mato Grosso, 306, cj 408, Higienópolis, São Paulo, SP, 01239-040, Brazil
| | - P de Sá Tavares Russo
- Fleury Group, Rua Mato Grosso, 306, cj 408, Higienópolis, São Paulo, SP, 01239-040, Brazil
| | - J P M Morgado
- Fleury Group, Rua Mato Grosso, 306, cj 408, Higienópolis, São Paulo, SP, 01239-040, Brazil
| | | | - J G H Vieira
- Fleury Group, Rua Mato Grosso, 306, cj 408, Higienópolis, São Paulo, SP, 01239-040, Brazil
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Mattoo S, Agarwal A, Mayilvaganan S, Mishra P, Agarwal G, Mishra A, Chand G, Gupta SK, Mishra SK. Role of postoperative intact serum PTH as an early predictor of severe post-thyroidectomy hypocalcemia: a prospective study. J Endocrinol Invest 2021; 44:1961-1970. [PMID: 33502721 DOI: 10.1007/s40618-021-01511-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 01/15/2021] [Indexed: 10/22/2022]
Abstract
BACKGROUND Post thyroidectomy hypocalcemia is a major sequel of thyroidectomy and continues to trouble the endocrinologists and the endocrine surgeons as there is no ideal predictive marker of hypocalcemia which has the potential to develop into a life-threatening complication. The role of early serum intact parathormone (iPTH) to predict post thyroidectomy hypocalcemia is becoming useful but the literature is still unclear regarding the optimal time of testing and the optimal cut-off value of serum iPTH. PATIENTS AND METHODS This is a prospective cohort study of 111 patients who underwent total thyroidectomy in a tertiary care endocrine surgery referral unit. Serum iPTH was measured after 20 min and 4 h of surgery. Receiver-Operator characteristic Curve (ROC) was used to find out of the best cut-off value of S. iPTH 20 min and 4 h after surgery in predicting hypocalcemia. RESULTS Hypocalcemia was noted in 60 (54%) out of 111 subjects who underwent total thyroidectomy. The best cut-off values of Serum iPTH to predict hypocalcemia was found to be 4.28 pmol/l at 20 min post total thyroidectomy with a sensitivity and specificity of 81.7% and 51%, respectively. In addition, patients with malignancy or central lymph nodal dissection were significantly over-represented in the hypocalcemia group with serum iPTH above the threshold level of 4.28 pmol/l. Below the cut off level, parenteral calcium supplementation was required in 23% (17/74) subjects while the rate was only 5.4% (2/37) patients when serum iPTH was above the cut-off level. CONCLUSIONS The decline of serum iPTH below a specific level after surgery has predictive value together with other factors strictly related to patient, the thyroid disease itself and surgery. The risk of development of hypocalcemia and consequent need for calcium supplementation should be evaluated by clinical assessment along with serum PTH measurement.
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Affiliation(s)
- S Mattoo
- Department of Endocrine Surgery, Sanjay Gandhi Postgraduate Institute of Medical Sciences (SGPGI), Lucknow, 226014, India
| | - A Agarwal
- Department of Endocrine Surgery, Sanjay Gandhi Postgraduate Institute of Medical Sciences (SGPGI), Lucknow, 226014, India.
| | - S Mayilvaganan
- Department of Endocrine Surgery, Sanjay Gandhi Postgraduate Institute of Medical Sciences (SGPGI), Lucknow, 226014, India
| | - P Mishra
- Department of Biostatistics and Health Informatics, Sanjay Gandhi Postgraduate Institute of Medical Sciences (SGPGI), Lucknow, 226014, India
| | - G Agarwal
- Department of Endocrine Surgery, Sanjay Gandhi Postgraduate Institute of Medical Sciences (SGPGI), Lucknow, 226014, India
| | - A Mishra
- Department of Endocrine Surgery, Sanjay Gandhi Postgraduate Institute of Medical Sciences (SGPGI), Lucknow, 226014, India
| | - G Chand
- Department of Endocrine Surgery, Sanjay Gandhi Postgraduate Institute of Medical Sciences (SGPGI), Lucknow, 226014, India
| | - S K Gupta
- Department of Endocrine Surgery, Sanjay Gandhi Postgraduate Institute of Medical Sciences (SGPGI), Lucknow, 226014, India
| | - S K Mishra
- Department of Endocrine Surgery, Sanjay Gandhi Postgraduate Institute of Medical Sciences (SGPGI), Lucknow, 226014, India
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Kritmetapak K, Losbanos LA, Hines JM, O'Grady KL, Ulmer CZ, Vesper HW, Enders FT, Singh RJ, Kumar R. Chemical Characterization and Quantification of Circulating Intact PTH and PTH Fragments by High-Resolution Mass Spectrometry in Chronic Renal Failure. Clin Chem 2021; 67:843-853. [PMID: 33693557 PMCID: PMC8167341 DOI: 10.1093/clinchem/hvab013] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 01/12/2021] [Indexed: 01/26/2023]
Abstract
BACKGROUND The precise concentrations of full-length parathyroid hormone (PTH1-84) and the identity and concentrations of PTH fragments in patients with various stages of chronic renal failure are unknown. METHODS We developed a liquid chromatography-high resolution mass spectrometry (LC-HRMS) method to characterize and quantify PTH1-84 and PTH fragments in serum of 221 patients with progressive renal dysfunction. Following capture by matrix-bound amino-terminal or carboxyl-terminal region-specific antibodies and elution from matrix, PTH1-84 and PTH fragments were identified and quantitated using LC-HRMS. PTH was simultaneously measured using an intact PTH (iPTH) immunoassay. RESULTS Full-length PTH1-84 and 8 PTH fragments (PTH28-84, 34-77, 34-84, 37-77, 37-84, 38-77, 38-84, and 45-84) were unequivocally identified and were shown to increase significantly when an eGFR declined to ≤17-23 mL/min/1.73m2. Serum concentrations of PTH1-84 were similar when measured by LC-HRMS following capture by amino-terminal or carboxyl-terminal immunocapture methods. In patients with an eGFR of <30 mL/min/1.73 m2, serum PTH concentrations measured using LC-HRMS were significantly lower than PTH measured using an iPTH immunoassay. PTH7-84 and oxidized forms of PTH1-84 were below the limit of detection (30 and 50 pg/mL, respectively). CONCLUSIONS LC-HRMS identifies circulating PTH1-84, carboxyl-terminal PTH fragments, and mid-region PTH fragments, in patients with progressive renal failure. Serum PTH1-84 and its fragments markedly rise when an eGFR decreases to ≤17-23 mL/min/1.73 m2. PTH concentrations measured using LC-HRMS tend to be lower than those measured using an iPTH immunoassay, particularly in severe chronic renal failure. Our data do not support the existence of circulating PTH7-84 and oxidized PTH1-84.
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Affiliation(s)
- Kittrawee Kritmetapak
- Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA.,Division of Nephrology, Department of Medicine, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Louis A Losbanos
- Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - Jolaine M Hines
- Immunochemical Core Laboratory, Mayo Clinic, Rochester, MN, USA
| | | | - Candice Z Ulmer
- Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Hubert W Vesper
- Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Felicity T Enders
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA
| | - Ravinder J Singh
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Rajiv Kumar
- Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA.,Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA
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Ercan M, Akbulut ED, Avcı E, Yücel Ç, Oğuz EF, Turhan T, Serdar M. Determining biological variation of serum parathyroid hormone in healthy adults. Biochem Med (Zagreb) 2019; 29:030702. [PMID: 31379460 PMCID: PMC6610671 DOI: 10.11613/bm.2019.030702] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 05/24/2019] [Indexed: 11/21/2022] Open
Abstract
Introduction Measurement of parathyroid hormone (PTH) is essential in the investigation and management of calcium metabolism disorders. To assess the significance of any assay result when clinical decision making biological variation (BV) of the measurand must be taken into consideration. The aim of the present study is determining the BV parameters for serum PTH. Materials and methods Blood samples were taken at weekly intervals from 20 healthy subjects for ten weeks in this prospective BV study. Serum “intact PTH” concentrations were measured with electrochemiluminescence method. Biological variation parameters were estimated using the approach proposed by Fraser. Results The values of within-subject biological variation (CVI), between-subject biological variation (CVG), analytical variation (CVA), reference change value (RCV) and individuality index (II) for serum PTH were 21.1%, 24.9%, 3.8%, 59.4% and 0.8%, respectively. Within-subject biological variation and CVG were also determined according to gender separately; 18.5% and 24.0%; 26.2% and 18.6% for male and female, respectively. Calculated desirable precision and bias goals were < 10.6% and < 6.3%, respectively. Conclusion This study may contribute to BV data on serum PTH as it includes a sufficient number of volunteers from both genders over an acceptable period of time. We do not recommend the usage of population-based reference intervals for serum PTH concentrations. Reference change value may be helpful for the evaluation of serial serum PTH results. Nonetheless, evaluation of data according to gender is necessary when setting analytical performance specifications.
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Affiliation(s)
- Müjgan Ercan
- Faculty of Medicine, Department of Biochemistry, Harran University, Şanlıurfa, Turkey
| | - Emiş Deniz Akbulut
- Biochemistry Laboratory, University of Health Sciences, Ankara Child Health and Diseases Hematology Oncology Training and Research Hospital, Ankara, Turkey
| | - Esin Avcı
- Faculty of Medicine, Department of Biochemistry, Pamukkale University, Denizli, Turkey
| | - Çiğdem Yücel
- Biochemistry Laboratory, Ankara Numune Training and Research Hospital, Ankara, Turkey
| | - Esra Fırat Oğuz
- Biochemistry Laboratory, Ankara Numune Training and Research Hospital, Ankara, Turkey
| | - Turan Turhan
- Biochemistry Laboratory, Ankara Numune Training and Research Hospital, Ankara, Turkey
| | - Muhittin Serdar
- Faculty of Medicine, Department of Biochemistry, Acıbadem University, İstanbul, Turkey
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Chandran M, Wong J. Secondary and Tertiary Hyperparathyroidism in Chronic Kidney Disease: An Endocrine and Renal Perspective. Indian J Endocrinol Metab 2019; 23:391-399. [PMID: 31741895 PMCID: PMC6844175 DOI: 10.4103/ijem.ijem_292_19] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Secondary Hyperparathyroidism (SHP) seen as a frequent complication in Chronic Kidney Disease (CKD) has many pathogenetic peculiarities that are still incompletely defined and understood. During the long course of chronic renal failure, SHP can also transform sometimes into the hypercalcemic state characterized by quasi-autonomous production of Parathyroid Hormone from the parathyroid glands: a disorder that is termed Tertiary Hyperparathyroidism. The clinical consequences of SHP in CKD are protean, encompassing bone and mineral abnormalities but as recently identified, also several metabolic and cardiovascular problems, the most important of which is vascular calcification. There have been several advances in the therapeutic armamentarium available for the treatment of SHP, though clear demonstration of a benefit regarding major clinical outcomes with any of the new agents is still lacking. This narrative review summarizes the current understanding about this disorder and highlights some of the recent research on the subject.
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Affiliation(s)
- Manju Chandran
- Department of Endocrinology, Osteoporosis and Bone Metabolism Unit, Singapore General Hospital, Singapore
| | - Jiunn Wong
- Department of Renal Medicine, Singapore General Hospital, Singapore
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Nyssen L, Fillet M, Cavalier E, Servais A. Highly sensitive and selective separation of intact parathyroid hormone and variants by sheathless CE‐ESI‐MS/MS. Electrophoresis 2019; 40:1550-1557. [DOI: 10.1002/elps.201800507] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 01/28/2019] [Accepted: 02/22/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Laurent Nyssen
- Department of Clinical ChemistryCenter for Interdisciplinary Research on Medicines (CIRM)University of Liège Liège Belgium
- Laboratory for the Analysis of Medicines (LAM)Center for Interdisciplinary Research on Medicines (CIRM)University of Liège Liège Belgium
| | - Marianne Fillet
- Laboratory for the Analysis of Medicines (LAM)Center for Interdisciplinary Research on Medicines (CIRM)University of Liège Liège Belgium
| | - Etienne Cavalier
- Department of Clinical ChemistryCenter for Interdisciplinary Research on Medicines (CIRM)University of Liège Liège Belgium
| | - Anne‐Catherine Servais
- Laboratory for the Analysis of Medicines (LAM)Center for Interdisciplinary Research on Medicines (CIRM)University of Liège Liège Belgium
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Schleck ML, Souberbielle JC, Delanaye P, Plebani M, Cavalier E. Parathormone stability in hemodialyzed patients and healthy subjects: comparison on non-centrifuged EDTA and serum samples with second- and third-generation assays. ACTA ACUST UNITED AC 2017; 55:1152-1159. [DOI: 10.1515/cclm-2016-0914] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 11/22/2016] [Indexed: 11/15/2022]
Abstract
Abstract
Background:
Parathyroid hormone (PTH) stability is important. Many studies have shown divergent results between EDTA and serum, which are mainly linked to differences in protocols or cut-offs used to determine whether or not PTH remained stable. No studies have yet compared PTH stability as measured by second- and third-generation assays on the same samples in hemodialyzed patients and healthy subjects.
Methods:
Five pairs of samples (EDTA and gel tubes) were obtained in 10 hemodialyzed patients before a dialysis session and in 10 healthy subjects. One pair was centrifuged and run directly to define the “T0”. Two pairs were kept at +4°C and two pairs were kept at +25°C. They were centrifuged after 4 and 18 h. Supernatant was kept at –80°C for 1 week. All samples were measured in a single batch, on Roche Cobas and DiaSorin XL second- and third-generation PTH assays. We used three different approaches to evaluate PTH stability: Wilcoxon test, an Acceptable Change Limit (ACL) according to ISO Guide 5725-6 and a Total Change Limit (TCL) derived from the sum of biological and technical variability according to WHO.
Results:
PTH decreased in all samples. Stability of PTH was mainly dependent on the way it was evaluated. Percentages of decrease were systematically lower in EDTA vs. serum. Wilcoxon and ACL showed that PTH was no more stable after 4 h at +4°C in EDTA or serum gel tubes. None of the subjects presented a PTH decrease higher than the TCL with EDTA plasma. In serum gel tubes, PTH was unstable only when kept at 25°C for 18 h.
Conclusions:
PTH seems more stable in EDTA than in serum gel tubes but only when samples have to stay unprocessed for a long period (18 h) at room temperature (25°C), which can happen when samples are delivered from external care centers. For all the other conditions, using serum gel tubes is recommended since calcium measurement, which is necessary for a good PTH results interpretation, can be achieved on the same tube.
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Piketty ML, Prie D, Sedel F, Bernard D, Hercend C, Chanson P, Souberbielle JC. High-dose biotin therapy leading to false biochemical endocrine profiles: validation of a simple method to overcome biotin interference. ACTA ACUST UNITED AC 2017; 55:817-825. [DOI: 10.1515/cclm-2016-1183] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2016] [Accepted: 01/13/2017] [Indexed: 12/16/2022]
Abstract
Abstract
Background:
High-dose biotin therapy is beneficial in progressive multiple sclerosis (MS) and is expected to be adopted by a large number of patients. Biotin therapy leads to analytical interference in many immunoassays that utilize streptavidin-biotin capture techniques, yielding skewed results that can mimic various endocrine disorders. We aimed at exploring this interference, to be able to remove biotin and avoid misleading results.
Methods:
We measured free triiodothyronine (fT3), free thyroxine (fT4), thyroid-stimulating hormone (TSH), parathyroid homrone (PTH), 25-hydroxyvitamin D (25OHD), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, C-peptide, cortisol (Roche Diagnostics assays), biotin and its main metabolites (liquid chromatography tandem mass spectrometry) in 23 plasmas from MS patients and healthy volunteers receiving high-dose biotin, and in 39 biotin-unsupplemented patients, before and after a simple procedure (designated N5) designed to remove biotin by means of streptavidin-coated microparticles. We also assayed fT4, TSH and PTH in the 23 high-biotin plasmas using assays not employing streptavidin-biotin binding.
Results:
The biotin concentration ranged from 31.7 to 1160 µg/L in the 23 high-biotin plasmas samples. After the N5 protocol, the biotin concentration was below the detection limit in all but two samples (8.3 and 27.6 μg/L). Most hormones results were abnormal, but normalized after N5. All results with the alternative methods were normal except two slight PTH elevations. In the 39 biotin-unsupplemented patients, the N5 protocol did not affect the results for any of the hormones, apart from an 8.4% decrease in PTH.
Conclusions:
We confirm that most streptavidin-biotin hormone immunoassays are affected by high biotin concentrations, leading to a risk of misdiagnosis. Our simple neutralization method efficiently suppresses biotin interference.
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Souberbielle JC, Brazier F, Piketty ML, Cormier C, Minisola S, Cavalier E. How the reference values for serum parathyroid hormone concentration are (or should be) established? J Endocrinol Invest 2017; 40:241-256. [PMID: 27696297 DOI: 10.1007/s40618-016-0553-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 09/09/2016] [Indexed: 10/20/2022]
Abstract
Well-validated reference values are necessary for a correct interpretation of a serum PTH concentration. Establishing PTH reference values needs recruiting a large reference population. Exclusion criteria for this population can be defined as any situation possibly inducing an increase or a decrease in PTH concentration. As recommended in the recent guidelines on the diagnosis and management of asymptomatic primary hyperparathyroidism, PTH reference values should be established in vitamin D-replete subjects with a normal renal function with possible stratification according to various factors such as age, gender, menopausal status, body mass index, and race. A consensus about analytical/pre-analytical aspects of PTH measurement is also needed with special emphasis on the nature of the sample (plasma or serum), the time and the fasting/non-fasting status of the blood sample. Our opinion is that blood sample for PTH measurement should be obtained in the morning after an overnight fast. Furthermore, despite longer stability of the PTH molecule in EDTA plasma, we prefer serum as it allows to measure calcium, a prerequisite for a correct interpretation of a PTH concentration, on the same sample. Once a consensus is reached, we believe an important international multicentre work should be performed to recruit a very extensive reference population of apparently healthy vitamin D-replete subjects with a normal renal function in order to establish the PTH normative data. Due to the huge inter-method variability in PTH measurement, a sufficient quantity of blood sample should be obtained to allow measurement with as many PTH kits as possible.
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Affiliation(s)
- J-C Souberbielle
- Service des Explorations Fonctionnelles, Hôpital Necker-Enfants Malades, 149 rue de Sèvres, 75015, Paris, France.
- Université René Descartes, 75015, Paris, France.
| | - F Brazier
- Service des Explorations Fonctionnelles, Hôpital Necker-Enfants Malades, 149 rue de Sèvres, 75015, Paris, France
- Université René Descartes, 75015, Paris, France
| | - M-L Piketty
- Service des Explorations Fonctionnelles, Hôpital Necker-Enfants Malades, 149 rue de Sèvres, 75015, Paris, France
- Université René Descartes, 75015, Paris, France
| | - C Cormier
- Rheumatology Department, Cochin University Hospital, 75014, Paris, France
| | - S Minisola
- Ordinario di Medicina Interna, Responsabile UOC Medicina Interna e Malattie Metaboliche dell'Osso (TMC 04), « Sapienza » Università di Roma, Rome, Italy
| | - E Cavalier
- Clinical Chemistry Department, Sart Tilman University Hospital, Liège, Belgium
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Cavalier E, Plebani M, Delanaye P, Souberbielle JC. Considerations in parathyroid hormone testing. Clin Chem Lab Med 2016; 53:1913-9. [PMID: 26035114 DOI: 10.1515/cclm-2015-0314] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 05/04/2015] [Indexed: 11/15/2022]
Abstract
Parathyroid hormone (PTH) is a major player in phosphocalcic metabolism and its measurement is very important for the correct diagnosis and treatment of several diseases. PTH determination represents the paradigm of quality in laboratory medicine as many variables in the pre-, intra-, and post-analytical phases strongly affect the value of the clinical information. Analytical determination of PTH has been rendered difficult by the presence, in the circulation, of truncated fragments that can cross-react with the antibodies used for its determination. In addition, pre-analytical phase is complicated by the lack of stability of the peptide and the best sample to use for its determination remains controversial, as well as sample handling and storage. PTH secretion is also affected by circadian and seasonal rhythms and by physical exercise. Finally, from the post-analytical perspective, establishment of reliable reference ranges requires further efforts as the selection criteria for reference subjects should take into consideration new variables such as gender, race and vitamin D levels. Finally, clinical guidelines have recently revised and improved the criteria for a correct interpretation of PTH values.
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Starker LF, Prieto PA, Liles JS, Tran Cao HS, Grubbs EG, Lee JE, Perrier ND, Graham PH. Endocrine incidentalomas. Curr Probl Surg 2016; 53:219-46. [DOI: 10.1067/j.cpsurg.2016.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 04/22/2016] [Indexed: 12/21/2022]
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Souberbielle JC, Massart C, Brailly-Tabard S, Cormier C, Cavalier E, Delanaye P, Chanson P. Serum PTH reference values established by an automated third-generation assay in vitamin D-replete subjects with normal renal function: consequences of diagnosing primary hyperparathyroidism and the classification of dialysis patients. Eur J Endocrinol 2016; 174:315-23. [PMID: 26628583 DOI: 10.1530/eje-15-0595] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 12/01/2015] [Indexed: 01/02/2023]
Abstract
OBJECTIVE To determine parathyroid hormone (PTH) reference values in French healthy adults, taking into account serum 25-hydroxyvitamin D (25OHD), renal function, age, gender, and BMI. PARTICIPANTS AND MAIN BIOLOGICAL MEASUREMENTS We studied 898 healthy subjects (432 women) aged 18-89 years with a normal BMI and estimated glomerular filtration rate (eGFR), 81 patients with surgically proven primary hyperparathyroidism (PHPT), and 264 dialysis patients. 25OHD and third-generation PTH assays were implemented on the LIAISON XL platform. RESULTS Median PTH and 25OHD values in the 898 healthy subjects were 18.8 ng/l and 23.6 ng/ml respectively. PTH was lower in subjects with 25OHD ≥30 ng/ml than in those with lower values. Among the 183 subjects with 25OHD ≥30 ng/ml, those aged ≥60 years (n=31) had higher PTH values than younger subjects, independent of 25OHD, BMI, and eGFR (P<0.001). Given the small number of subjects aged ≥60 years, we adopted the 95% CI of PTH values for the entire group of 183 vitamin D-replete subjects (9.4-28.9 ng/l) as our reference values. With 28.9 ng/l as the upper limit of normal (ULN) rather than the manufacturer's ULN of 38.4 ng/l, the percentage of PHPT patients with 'high' PTH values rose to 90.1% from 66.6% (P<0.001), and 18.6% of the dialysis patients were classified differently in view of the KDIGO target range (two to nine times the ULN). CONCLUSION When only subjects with 25OHD ≥30 ng/ml were included in the reference population, the PTH ULN fell by 22.4%, diagnostic sensitivity for PHPT improved, and the classification of dialysis patients was modified.
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Affiliation(s)
| | - Catherine Massart
- Service des Explorations FonctionnellesNecker-Enfants Malades University Hospital, 149 Rue de Sèvres, Paris F75015, FranceHormonology LaboratoryPontchaillou University Hospital, Rennes F29000, FranceService de Génétique MoléculairePharmacogénétique et Hormonologie, F-94275 Le Kremlin-Bicêtre, FranceFaculté de Médecine Paris-SudUnité Mixte de Recherche-S1185, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceInstitut National de la Santé et de la Recherche Médicale (INSERM) U1185F-94276 Le Kremlin-Bicêtre, FranceRheumatology DepartmentCochin University Hospital, Paris F75014, FranceClinical Chemistry DepartmentSart Tilman University Hospital, Liège, BelgiumNephrology and Dialysis DepartmentSart Tilman University Hospital, Liège, BelgiumAssistance Publique-Hôpitaux de ParisHôpital de Bicêtre, Service d'Endocrinologie et des Maladies de la Reproduction and Centre de Référence des Maladies Endocriniennes Rares de la Croissance, F94275 Le Kremlin-Bicêtre, FranceUMR S1185Faculté de Médecine Paris-Sud, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceINSERM U1185F-94276 Le Kremlin-Bicêtre, France
| | - Sylvie Brailly-Tabard
- Service des Explorations FonctionnellesNecker-Enfants Malades University Hospital, 149 Rue de Sèvres, Paris F75015, FranceHormonology LaboratoryPontchaillou University Hospital, Rennes F29000, FranceService de Génétique MoléculairePharmacogénétique et Hormonologie, F-94275 Le Kremlin-Bicêtre, FranceFaculté de Médecine Paris-SudUnité Mixte de Recherche-S1185, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceInstitut National de la Santé et de la Recherche Médicale (INSERM) U1185F-94276 Le Kremlin-Bicêtre, FranceRheumatology DepartmentCochin University Hospital, Paris F75014, FranceClinical Chemistry DepartmentSart Tilman University Hospital, Liège, BelgiumNephrology and Dialysis DepartmentSart Tilman University Hospital, Liège, BelgiumAssistance Publique-Hôpitaux de ParisHôpital de Bicêtre, Service d'Endocrinologie et des Maladies de la Reproduction and Centre de Référence des Maladies Endocriniennes Rares de la Croissance, F94275 Le Kremlin-Bicêtre, FranceUMR S1185Faculté de Médecine Paris-Sud, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceINSERM U1185F-94276 Le Kremlin-Bicêtre, France Service des Explorations FonctionnellesNecker-Enfants Malades University Hospital, 149 Rue de Sèvres, Paris F75015, FranceHormonology LaboratoryPontchaillou University Hospital, Rennes F29000, FranceService de Génétique MoléculairePharmacogénétique et Hormonologie, F-94275 Le Kremlin-Bicêtre, FranceFaculté de Médecine Paris-SudUnité Mixte de Recherche-S1185, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceInstitut National de la Santé et de la Recherche Médicale (INSERM) U1185F-94276 Le Kremlin-Bicêtre, FranceRheumatology DepartmentCochin University Hospital, Paris F75014, FranceClinical Chemistry DepartmentSart Tilman University Hospital, Liège, BelgiumNephrology and Dialysis DepartmentSart Tilman University Hospital, Liège, BelgiumAssistance Publique-Hôpita
| | - Catherine Cormier
- Service des Explorations FonctionnellesNecker-Enfants Malades University Hospital, 149 Rue de Sèvres, Paris F75015, FranceHormonology LaboratoryPontchaillou University Hospital, Rennes F29000, FranceService de Génétique MoléculairePharmacogénétique et Hormonologie, F-94275 Le Kremlin-Bicêtre, FranceFaculté de Médecine Paris-SudUnité Mixte de Recherche-S1185, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceInstitut National de la Santé et de la Recherche Médicale (INSERM) U1185F-94276 Le Kremlin-Bicêtre, FranceRheumatology DepartmentCochin University Hospital, Paris F75014, FranceClinical Chemistry DepartmentSart Tilman University Hospital, Liège, BelgiumNephrology and Dialysis DepartmentSart Tilman University Hospital, Liège, BelgiumAssistance Publique-Hôpitaux de ParisHôpital de Bicêtre, Service d'Endocrinologie et des Maladies de la Reproduction and Centre de Référence des Maladies Endocriniennes Rares de la Croissance, F94275 Le Kremlin-Bicêtre, FranceUMR S1185Faculté de Médecine Paris-Sud, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceINSERM U1185F-94276 Le Kremlin-Bicêtre, France
| | - Etienne Cavalier
- Service des Explorations FonctionnellesNecker-Enfants Malades University Hospital, 149 Rue de Sèvres, Paris F75015, FranceHormonology LaboratoryPontchaillou University Hospital, Rennes F29000, FranceService de Génétique MoléculairePharmacogénétique et Hormonologie, F-94275 Le Kremlin-Bicêtre, FranceFaculté de Médecine Paris-SudUnité Mixte de Recherche-S1185, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceInstitut National de la Santé et de la Recherche Médicale (INSERM) U1185F-94276 Le Kremlin-Bicêtre, FranceRheumatology DepartmentCochin University Hospital, Paris F75014, FranceClinical Chemistry DepartmentSart Tilman University Hospital, Liège, BelgiumNephrology and Dialysis DepartmentSart Tilman University Hospital, Liège, BelgiumAssistance Publique-Hôpitaux de ParisHôpital de Bicêtre, Service d'Endocrinologie et des Maladies de la Reproduction and Centre de Référence des Maladies Endocriniennes Rares de la Croissance, F94275 Le Kremlin-Bicêtre, FranceUMR S1185Faculté de Médecine Paris-Sud, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceINSERM U1185F-94276 Le Kremlin-Bicêtre, France
| | - Pierre Delanaye
- Service des Explorations FonctionnellesNecker-Enfants Malades University Hospital, 149 Rue de Sèvres, Paris F75015, FranceHormonology LaboratoryPontchaillou University Hospital, Rennes F29000, FranceService de Génétique MoléculairePharmacogénétique et Hormonologie, F-94275 Le Kremlin-Bicêtre, FranceFaculté de Médecine Paris-SudUnité Mixte de Recherche-S1185, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceInstitut National de la Santé et de la Recherche Médicale (INSERM) U1185F-94276 Le Kremlin-Bicêtre, FranceRheumatology DepartmentCochin University Hospital, Paris F75014, FranceClinical Chemistry DepartmentSart Tilman University Hospital, Liège, BelgiumNephrology and Dialysis DepartmentSart Tilman University Hospital, Liège, BelgiumAssistance Publique-Hôpitaux de ParisHôpital de Bicêtre, Service d'Endocrinologie et des Maladies de la Reproduction and Centre de Référence des Maladies Endocriniennes Rares de la Croissance, F94275 Le Kremlin-Bicêtre, FranceUMR S1185Faculté de Médecine Paris-Sud, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceINSERM U1185F-94276 Le Kremlin-Bicêtre, France
| | - Philippe Chanson
- Service des Explorations FonctionnellesNecker-Enfants Malades University Hospital, 149 Rue de Sèvres, Paris F75015, FranceHormonology LaboratoryPontchaillou University Hospital, Rennes F29000, FranceService de Génétique MoléculairePharmacogénétique et Hormonologie, F-94275 Le Kremlin-Bicêtre, FranceFaculté de Médecine Paris-SudUnité Mixte de Recherche-S1185, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceInstitut National de la Santé et de la Recherche Médicale (INSERM) U1185F-94276 Le Kremlin-Bicêtre, FranceRheumatology DepartmentCochin University Hospital, Paris F75014, FranceClinical Chemistry DepartmentSart Tilman University Hospital, Liège, BelgiumNephrology and Dialysis DepartmentSart Tilman University Hospital, Liège, BelgiumAssistance Publique-Hôpitaux de ParisHôpital de Bicêtre, Service d'Endocrinologie et des Maladies de la Reproduction and Centre de Référence des Maladies Endocriniennes Rares de la Croissance, F94275 Le Kremlin-Bicêtre, FranceUMR S1185Faculté de Médecine Paris-Sud, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceINSERM U1185F-94276 Le Kremlin-Bicêtre, France Service des Explorations FonctionnellesNecker-Enfants Malades University Hospital, 149 Rue de Sèvres, Paris F75015, FranceHormonology LaboratoryPontchaillou University Hospital, Rennes F29000, FranceService de Génétique MoléculairePharmacogénétique et Hormonologie, F-94275 Le Kremlin-Bicêtre, FranceFaculté de Médecine Paris-SudUnité Mixte de Recherche-S1185, Univ Paris-Sud, Université Paris-Saclay, F-94276 Le Kremlin-Bicêtre, FranceInstitut National de la Santé et de la Recherche Médicale (INSERM) U1185F-94276 Le Kremlin-Bicêtre, FranceRheumatology DepartmentCochin University Hospital, Paris F75014, FranceClinical Chemistry DepartmentSart Tilman University Hospital, Liège, BelgiumNephrology and Dialysis DepartmentSart Tilman University Hospital, Liège, BelgiumAssistance Publique-Hôpita
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Shibli-Rahhal A, Paturi B. Variations in parathyroid hormone concentration in patients with low 25 hydroxyvitamin D. Osteoporos Int 2014; 25:1931-6. [PMID: 24647889 DOI: 10.1007/s00198-014-2687-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 03/12/2014] [Indexed: 01/01/2023]
Abstract
UNLABELLED Although 25 hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) levels are inversely related, less than half of the patients with a low vitamin D level have an elevated PTH, and, in most of these patients, the PTH does not immediately normalize with correction of the vitamin D. INTRODUCTION Despite the inverse relationship between 25OHD and PTH, patients with vitamin D deficiency seen in clinical practice do not always have an elevated PTH, and, in those with secondary hyperparathyroidism, the PTH does not always normalize with correction of vitamin D deficiency. We examined variations in PTH concentrations in patients with low 25OHD and studied changes in the PTH concentration with restoration of vitamin D sufficiency. METHODS This was a retrospective cohort study of patients with a 25OHD < 30 ng/mL and a concomitant PTH measurement seen at the Metabolic Bone Disease Clinic at a tertiary care center between July 1, 2007 and May 31, 2011. Patients with conditions associated with alterations in PTH were excluded. RESULTS The study population consisted of 104 patients. The mean age was 55.5 years, and 83 % were female. The 25OHD and PTH were negatively correlated, but only 30 % of patients with a 25OHD < 30 ng/mL and 40 % of those with a 25OHD < 20 ng/mL had an elevated PTH. As the 25OHD increased to 30 ng/mL or higher, the PTH decreased significantly in the group of patients who had an elevated PTH at baseline, but only 44 % reached a normal PTH. Of patients with a normal PTH at baseline, 59 % experienced a drop in their PTH while the PTH remained unchanged or increased in 41 %. CONCLUSIONS PTH has a limited role in defining vitamin D status in individual patients and in guiding vitamin D therapy in clinical practice.
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Affiliation(s)
- A Shibli-Rahhal
- Division of Endocrinology, Diabetes, and Metabolism, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA, USA,
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Abstract
The emergence of fibroblast growth factor 23 as a potentially modifiable risk factor in CKD has led to growing interest in its measurement as a tool to assess patient risk and target therapy. This review discusses the analytical and clinical challenges faced in translating fibroblast growth factor 23 testing into routine practice. As for other bone mineral markers, agreement between commercial fibroblast growth factor 23 assays is poor, mainly because of differences in calibration, but also, these differences reflect the variable detection of hormone fragments. Direct comparison of readout from different assays is consequently limited and likely hampers setting uniform fibroblast growth factor 23-directed targets. Efforts are needed to standardize assay output to enhance clinical use. Fibroblast growth factor 23 is robustly associated with cardiovascular and renal outcomes in patients with CKD and adds value to risk assessments based on conventional risk factors. Compared with most other mineral markers, fibroblast growth factor 23 shows better intraindividual temporal stability, with minimal diurnal and week-to-week variability, but substantial interindividual variation, maximizing discriminative power for risk stratification. Conventional therapeutic interventions for the CKD-mineral bone disorder, such as dietary phosphate restriction and use of oral phosphate binders or calcimimetics, are associated with variable efficacy at modulating circulating fibroblast growth factor 23 concentrations, like they are for other mineral metabolites. Dual therapy with dietary phosphate restriction and noncalcium-based binder use achieves the most consistent fibroblast growth factor 23-lowering effect and seems best monitored using an intact assay. Additional studies are needed to evaluate whether strategies aimed at reducing levels or antagonizing its action have beneficial effects on clinical outcomes in CKD patients. Moreover, a better understanding of the mechanisms driving fibroblast growth factor 23 elevations in CKD is needed to inform the use of therapeutic interventions targeting fibroblast growth factor 23 excess. This evidence must be forthcoming to support the use of fibroblast growth factor 23 measurement and fibroblast growth factor 23-directed therapy in the clinic.
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Affiliation(s)
- Edward R Smith
- Department of Nephrology, The Royal Melbourne Hospital, Melbourne, Victoria, Australia
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Touvier M, Deschasaux M, Montourcy M, Sutton A, Charnaux N, Kesse-Guyot E, Fezeu LK, Latino-Martel P, Druesne-Pecollo N, Malvy D, Galan P, Hercberg S, Ezzedine K, Souberbielle JC. Interpretation of plasma PTH concentrations according to 25OHD status, gender, age, weight status, and calcium intake: importance of the reference values. J Clin Endocrinol Metab 2014; 99:1196-203. [PMID: 24527713 DOI: 10.1210/jc.2013-3349] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
CONTEXT Reference values for plasma PTH assessment were generally established on small samples of apparently healthy subjects, without considering their 25-hydroxyvitamin D (25OHD) status or other potential modifiers of PTH concentration. OBJECTIVE Our objective was to assess ranges of plasma PTH concentration in a large sample of adults, stratifying by 25OHD status, age, gender, weight status, and calcium intake. DESIGN, SETTING, AND PARTICIPANTS This cross-sectional survey is based on 1824 middle-aged Caucasian adults from the Supplémentation en Vitamines et Minéraux Antioxydants study (1994). MAIN OUTCOME MEASURES Plasma PTH and 25OHD concentrations were measured by an electrochemoluminescent immunoassay. Extreme percentiles of plasma PTH concentrations were assessed specifically in subjects who had plasmatic values of 25OHD of 20 ng/mL or greater and 30 ng/mL or greater. RESULTS Among subjects with 25OHD status of 20 ng/mL or greater, the 97.5th percentile of plasma PTH concentration was 45.5 ng/L. By using this value as a reference, 5% of the subjects with plasma 25OHD less than 20 nmol/L had a high plasma PTH level, reflecting secondary hyperparathyroidism. Among vitamin D-replete subjects (25OHD status of 20 ng/mL or greater), the 97.5th percentile of plasma PTH was higher in overweight/obese subjects (51.9 vs 43.5 ng/L among normal weight subjects). CONCLUSIONS The reference value for plasma PTH defined in this vitamin D-replete population was far below the value currently provided by the manufacturer (65 ng/L) and varied according to overweight status. These results may contribute to improve the diagnosis of primary and secondary hyperparathyroidism and subsequent therapeutic indication.
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Affiliation(s)
- Mathilde Touvier
- Sorbonne Paris Cité Research Center (M.T., M.D., M.M., E.K.-G., L.K.F., P.L.-M., N.D.-P., P.G., S.H., K.E.), Nutritional Epidemiology Research Team, INSERM Unité 557, Institut National de la Recherche Agronomique Unité 1125, Conservatoire National des Arts et Métiers, and INSERM Unité 698 (A.S., N.C.), Paris 13 University, F-93017 Bobigny, France; Department Biochemistry (A.S., N.C.), Jean Verdier Hospital, F-93143 Bondy, France; Department of Dermatology (D.M., K.E.), St André Hospital, F-33000 Bordeaux, France; Department of Public Health (S.H.), Avicenne Hospital, F-93009 Bobigny, France; and Department of Physiology (J.-C.S.), Necker Hospital (Assistance Publique-Hôpitaux de Paris), and INSERM Unité 845, F-75270 Paris, France
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Bowen RAR, Remaley AT. Interferences from blood collection tube components on clinical chemistry assays. Biochem Med (Zagreb) 2014; 24:31-44. [PMID: 24627713 PMCID: PMC3936985 DOI: 10.11613/bm.2014.006] [Citation(s) in RCA: 180] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 01/03/2014] [Indexed: 12/21/2022] Open
Abstract
Improper design or use of blood collection devices can adversely affect the accuracy of laboratory test results. Vascular access devices, such as catheters and needles, exert shear forces during blood flow, which creates a predisposition to cell lysis. Components from blood collection tubes, such as stoppers, lubricants, surfactants, and separator gels, can leach into specimens and/or adsorb analytes from a specimen; special tube additives may also alter analyte stability. Because of these interactions with blood specimens, blood collection devices are a potential source of pre-analytical error in laboratory testing. Accurate laboratory testing requires an understanding of the complex interactions between collection devices and blood specimens. Manufacturers, vendors, and clinical laboratorians must consider the pre-analytical challenges in laboratory testing. Although other authors have described the effects of endogenous substances on clinical assay results, the effects/impact of blood collection tube additives and components have not been well systematically described or explained. This review aims to identify and describe blood collection tube additives and their components and the strategies used to minimize their effects on clinical chemistry assays.
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Affiliation(s)
- Raffick A R Bowen
- Department of Pathology, Stanford University, Stanford, CA 94305, USA
| | - Alan T Remaley
- Department of Laboratory Medicine, National Institutes of Health, Bethesda, MD 20892, USA
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Deckers M, de Jongh R, Lips P, Penninx B, Milaneschi Y, Smit J, van Schoor N, Blankenstein M, Heijboer A. Prevalence of vitamin D deficiency and consequences for PTH reference values. Clin Chim Acta 2013; 426:41-5. [DOI: 10.1016/j.cca.2013.08.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 08/06/2013] [Accepted: 08/28/2013] [Indexed: 11/26/2022]
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Eddington H, Hudson JE, Oliver RL, Fraser WD, Hutchison AJ, Kalra PA. Variability in parathyroid hormone assays confounds clinical practice in chronic kidney disease patients. Ann Clin Biochem 2013; 51:228-36. [PMID: 24000371 DOI: 10.1177/0004563213491236] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Intact parathyroid hormone (iPTH) measurements are used to guide therapy in renal patients, but variability in results can occur depending on the assay used. This study has investigated iPTH assay variation in North West England and paired data with regional audit data to determine clinical relevance of assay variability. METHODS Thirty-seven haemodialysis patients had blood taken (EDTA plasma, and serum), and samples were processed at 17 laboratories that analyse iPTH for North West dialysis patients. Correction factors were calculated and applied to the iPTH assay results to enable direct comparisons. These correction factors were also applied to Regional Audit data to determine if iPTH assay variability explains the variation in unit performance in achieving PTH targets. RESULTS The iPTH results from the 37 patients were significantly different when either analysed by different assays and/or different laboratories (P < 0.001). The Abbott Architect method consistently produced the highest iPTH results. Of the 37 patients, between 49% and 65% would achieve the Kidney Disease: Improving Global Outcomes (KDIGO) iPTH target depending on the assay used. When results were adjusted using correction factors, 21% of the patients would require a change of management according to guidelines. Data from all haemodialysis units submitted for the regional audit were adjusted to the Roche assay and this led to a small change in achievement of KDIGO iPTH targets in individual units when compared to each other. CONCLUSIONS A combination of iPTH assay variability and diversity in clinical management leads to variation in achieving iPTH targets. Both need to be improved and/or standardized to improve patient care.
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Affiliation(s)
- Helen Eddington
- Renal Department, Manchester Academic Health Science Centre, Salford Royal Hospital, The University of Manchester, Salford, UK
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Fukagawa M, Yokoyama K, Koiwa F, Taniguchi M, Shoji T, Kazama JJ, Komaba H, Ando R, Kakuta T, Fujii H, Nakayama M, Shibagaki Y, Fukumoto S, Fujii N, Hattori M, Ashida A, Iseki K, Shigematsu T, Tsukamoto Y, Tsubakihara Y, Tomo T, Hirakata H, Akizawa T. Clinical Practice Guideline for the Management of Chronic Kidney Disease-Mineral and Bone Disorder. Ther Apher Dial 2013; 17:247-88. [DOI: 10.1111/1744-9987.12058] [Citation(s) in RCA: 251] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Bacchetta J, Wesseling-Perry K, Kuizon B, Pereira RC, Gales B, Wang HJ, Elashoff R, Salusky IB. The skeletal consequences of growth hormone therapy in dialyzed children: a randomized trial. Clin J Am Soc Nephrol 2013; 8:824-32. [PMID: 23559676 PMCID: PMC3641609 DOI: 10.2215/cjn.00330112] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Accepted: 01/03/2013] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND OBJECTIVE The effects of recombinant human growth hormone on renal osteodystrophy are unknown; thus, the effects of growth hormone (GH) on bone histomorphometry were assessed in pediatric patients with ESRD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Thirty-three patients who underwent bone biopsy between July 1994 and May 1999 were randomly assigned to therapy with or without GH. Patients were stratified by bone formation rate; all patients with high bone turnover received intraperitoneal calcitriol. Serum biochemical values were obtained monthly, and bone biopsy was repeated after 8 months. RESULTS Median patient age was 11.7 years (interquartile range [IQR], 7.6, 14.1 years); 45% of patients were male, and 52% were prepubertal. Median dialysis duration was 0.4 (IQR, 0.3, 0.8) year. Bone formation rate per bone surface increased from 15.0 (9.6, 21.8) to 154.6 (23.7, 174.3) μm(2)/μm(3) per year (P=0.05) in patients with low bone turnover treated with GH, decreased from 103.3 (57.0, 173.4) to 60.3 (20.3, 13.7) μm(2)/μm(3) per year in patients with high bone turnover receiving standard therapy (P=0.03), and was unchanged in the other two groups. Bone formation rates were higher with GH, irrespective of underlying bone histologic features (P=0.05). Parathyroid hormone did not differ between groups. GH therapy resulted in greater increases in height SD scores (estimated mean difference in change ± SD, 0.324±0.076; P<0.001), irrespective of underlying bone histologic features. CONCLUSIONS GH therapy improves height in pediatric dialysis patients, irrespective of underlying bone histologic features. Bone formation rates are higher in GH recipients, and GH therapy alters the relationship between circulating parathyroid hormone values and bone turnover.
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Affiliation(s)
| | | | | | | | | | - He-jing Wang
- Department of Biomathematics, David Geffen School of Medicine at UCLA, Los Angeles, California, and
| | - Robert Elashoff
- Department of Biomathematics, David Geffen School of Medicine at UCLA, Los Angeles, California, and
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Jia T, Qureshi AR, Brandenburg V, Ketteler M, Barany P, Heimburger O, Uhlin F, Magnusson P, Fernström A, Lindholm B, Stenvinkel P, Larsson TE. Determinants of fibroblast growth factor-23 and parathyroid hormone variability in dialysis patients. Am J Nephrol 2013; 37:462-71. [PMID: 23635517 DOI: 10.1159/000350537] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Accepted: 03/06/2013] [Indexed: 01/22/2023]
Abstract
BACKGROUND/AIMS Treatment strategies for abnormal mineral metabolism in chronic kidney disease are largely based on achieving target ranges of biomarkers that vary considerably over time, yet determinants of their variability are poorly defined. METHODS Observational study including 162 patients of three dialysis cohorts (peritoneal dialysis, n = 78; hemodialysis, n = 49; hemodiafiltration, n = 35). Clinical and biochemical determinants of parathyroid hormone (PTH) and fibroblast growth factor-23 (FGF23) variability were analyzed in the peritoneal dialysis cohort. All cohorts were used for comparison of PTH and FGF23 intra-subject variability (intra-class correlation), and their intra-subject variability in different modes of dialysis was explored. RESULTS High PTH variability was independently associated with lower 25-hydroxyvitamin D concentration and factors of lipid and glucose metabolism, whereas high FGF23 variability was mainly associated with lower baseline serum phosphorous. These results were consistent in multivariate and sensitivity analyses. The intra-subject variability of FGF23 was lower than for PTH irrespective of dialysis mode. CONCLUSIONS Baseline vitamin D status and serum phosphorous are independent determinants of the longitudinal variation in PTH and FGF23, respectively. The clinical utility of FGF23 measurement remains unknown, yet it appears favorable based on its greater temporal stability than PTH in dialysis patients.
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Affiliation(s)
- Ting Jia
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
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Zitt E, Fouque D, Jacobson SH, Malberti F, Ryba M, Ureña P, Rix M, Dehmel B, Manamley N, Vervloet M. Serum phosphorus reduction in dialysis patients treated with cinacalcet for secondary hyperparathyroidism results mainly from parathyroid hormone reduction. Clin Kidney J 2013; 6:287-294. [PMID: 23717787 PMCID: PMC3665312 DOI: 10.1093/ckj/sft026] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Accepted: 02/21/2013] [Indexed: 11/15/2022] Open
Abstract
Background The calcimimetic cinacalcet lowers parathyroid hormone (PTH), calcium (Ca) and phosphorus (P) in dialysis patients with secondary hyperparathyroidism (SHPT). We explored serum P changes in dialysis patients treated with cinacalcet, while controlling for vitamin D sterol and phosphate binder (PB) changes, based on data from the pan-European observational study ECHO. Methods Patients were categorized by serum P change (decreased/unchanged/increased) at 12 months after starting cinacalcet and subcategorized by vitamin D sterol and PB dose changes (decreased/unchanged/increased). The impact of PTH, Ca and P, and vitamin D sterol, PB and cinacalcet doses (absolute values and/or change) was evaluated. Predictors of P change were explored using univariate and multivariate general linear models (GLM) and logistic regression analysis. Results At Month 12, 661 (41%) of 1607 patients had decreased, 61 (4%) unchanged and 400 (25%) increased serum P, while 485 patients had missing data. In 45% of the patients with serum P reduction, vitamin D was either increased or unchanged and P binders decreased or unchanged. PTH was a key predictor of serum P reduction, with an estimated 3% decrease in P per 10% reduction in PTH. Changes in vitamin D sterol and PB doses were not generally significant factors in GLM and regression analyses. Conclusions The serum P reduction observed in a significant proportion of dialysis patients after adding cinacalcet to an existing therapeutic regimen for SHPT appears to result mainly from PTH reduction, rather than from changes in vitamin D sterol or PB doses. Financial support for the ECHO study was provided by Amgen.
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Affiliation(s)
- Emanuel Zitt
- Academic Teaching Hospital , Feldkirch , Austria
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Wesseling-Perry K, Salusky IB. Phosphate binders, vitamin D and calcimimetics in the management of chronic kidney disease-mineral bone disorders (CKD-MBD) in children. Pediatr Nephrol 2013; 28:617-25. [PMID: 23381010 PMCID: PMC3804000 DOI: 10.1007/s00467-012-2381-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 11/21/2012] [Accepted: 11/26/2012] [Indexed: 12/27/2022]
Abstract
In order to minimize complications on the skeleton and to prevent extraskeletal calcifications, the specific aims of the management of chronic kidney disease mineral and bone disorder (CKD-MBD) are to maintain blood levels of serum calcium and phosphorus as close to the normal range as possible, thereby maintaining serum parathyroid hormone (PTH) at levels appropriate for CKD stage, preventing hyperplasia of the parathyroid glands, avoiding the development of extra-skeletal calcifications, and preventing or reversing the accumulation of toxic substances such as aluminum and β2-microglobulin. In order to limit cardiovascular calcification, daily intake of elemental calcium, including from dietary sources and from phosphate binders, should not exceed twice the daily recommended intake for age and should not exceed 2.5 g/day. Calcium-free phosphate binders, such as sevelamer hydrochloride and sevelamer carbonate, are safe and effective alternatives to calcium-based binders, and their use widens the margin of safety for active vitamin D sterol therapy. Vitamin D deficiency is highly prevalent across the spectrum of CKD, and replacement therapy is recommended in vitamin D-deficient and insufficient individuals. Therapy with active vitamin D sterols is recommended after correction of the vitamin D deficiency state and should be titrated based on target PTH levels across the spectrum of CKD. Although the use of calcimimetic drugs has been proven to effectively control the biochemical features of secondary hyperparathyroidism, there is very limited experience with the use of such agents in pediatric patients and especially during the first years of life. Studies are needed to further define the role of such agents in the treatment of pediatric CKD-MBD.
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Wesseling-Perry K. Bone disease in pediatric chronic kidney disease. Pediatr Nephrol 2013; 28:569-76. [PMID: 23064662 PMCID: PMC3594120 DOI: 10.1007/s00467-012-2324-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 08/13/2012] [Accepted: 08/26/2012] [Indexed: 01/07/2023]
Abstract
Children with long-standing chronic kidney disease (CKD) display clinical symptoms of bone disease, including bony deformities and fractures, which contribute to long-standing disability. Abnormalities in skeletal mineralization occur in a substantial proportion of this population and may contribute to chronic morbidity. Underscoring the potential contribution of parameters other than bone turnover to bone disease in CKD, a new definition for renal osteodystrophy (ROD), emphasizing the assessment of three key histologic descriptors, i.e., bone turnover (T), mineralization (M), and volume (V) (TMV), has been recommended in the assessment of all patients with CKD. Although bone biopsy is the only available method for assessing all three recommended areas of bone histology, this invasive procedure is not routinely used in any clinical setting; thus, a true understanding of the prevalence of abnormal turnover, defective mineralization, and altered bone volume throughout the course of CKD is limited. Recent data, however, have shed light on the progression of renal ROD throughout the course of CKD, including its early stages, as well as on the alterations in cell biology that accompany ROD.
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Affiliation(s)
- Katherine Wesseling-Perry
- Department of Pediatrics, David Geffen School of Medicine at UCLA, A2-383 MDCC, 650 Charles Young Drive, Los Angeles, CA, 90095, USA.
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Switching between parathormone (PTH) assays: the impact on the diagnosis of renal osteodystrophy. Clin Chem Lab Med 2013; 51:1251-6. [DOI: 10.1515/cclm-2012-0485] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 11/07/2012] [Indexed: 11/15/2022]
Abstract
AbstractClinical guidelines for decision-making in chronic kidney disease (CKD) consider parathormone (PTH) levels. The measured PTH values differ if novel full length PTH(1-84) assays are used instead of earlier intact iPTH assays. In this study we analyzed how the classification of CKD patients alters when iPTH assays are switched to PTH(1-84) assays.Plasma samples were collected prior to dialysis sessions from 110 consecutive CKD patients on maintenance hemodialysis. PTH levels were determined with iPTH assays (Elecsys, Architect and DiaSorin Liaison N-tact) and PTH(1-84) assays (Elecsys and Liaison). Using KDIGO guidelines patients were classified as being below, above and in the recommended target range (RTR) of PTH. The results of classification with different assays were evaluated and, a novel calculation method of RTR was implemented.The prevalence of patients with PTH in RTR is comparable with each assay, but the individual patients differed. PTH(1-84) Elecsys and Liaison assays classified more patients as being below RTR than iPTH Elecsys and Architect but not Liaison N-tact assay (27.3%, 22.7% vs. 41%, 31.8%, and 36.4%, respectively). In turn, PTH(1-84) Elecsys and Liaison assays identified less CKD patients with PTH above the RTR than iPTH except N-tact assays (6.4%, 10% vs. 16.3%, 19%, and 6.3%, respectively). Using our calculation method, our discrimination values for PTH(1-84) assays to achieve classification identical to that with iPTH Elecsys were lower than those recommended by the manufacturer.Current guidelines for the treatment of secondary hyperparathyroidism in CKD should consider the type of assays used for PTH measurement. Each laboratory should assess its own RTR for PTH tests to achieve comparable classification. The presented calculation is simple, it mimics an everyday situation, switching from one assay to another one, and provides useful RTR values for PTH tests.
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Hanon EA, Sturgeon CM, Lamb EJ. Sampling and storage conditions influencing the measurement of parathyroid hormone in blood samples: a systematic review. Clin Chem Lab Med 2013; 51:1925-41. [DOI: 10.1515/cclm-2013-0315] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Indexed: 01/01/2023]
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Kiattisunthorn K, Moe SM. Chronic Kidney Disease-Mineral Bone Disorder: Definitions and Rationale for a Systemic Disorder. Clin Rev Bone Miner Metab 2012. [DOI: 10.1007/s12018-011-9119-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Weiner DE, Winkelmayer WC. Commentary on ‘The DOPPS Practice Monitor for US Dialysis Care: Trends Through August 2011': An ESA Confluence. Am J Kidney Dis 2012; 60:165-7. [DOI: 10.1053/j.ajkd.2012.04.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Accepted: 04/03/2012] [Indexed: 11/11/2022]
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Sturgeon CM, Sprague SM, Metcalfe W. Variation in parathyroid hormone immunoassay results--a critical governance issue in the management of chronic kidney disease. Nephrol Dial Transplant 2012; 26:3440-5. [PMID: 22039013 PMCID: PMC3203632 DOI: 10.1093/ndt/gfr614] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Renal physicians strive to maintain parathyroid hormone (PTH) concentrations for patients with chronic kidney disease (CKD) within guideline limits, but poor method comparability means there is currently serious risk of clinical misclassification. The potential for under- or over-treatment is significant, representing a major challenge to patient safety. In the short-term, raising awareness of clinical implications of method-related differences in PTH is essential. Agreeing and adopting assay-specific PTH action limits for CKD patients as an interim measure is highly desirable and has been achieved in Scotland. Establishing pre-analytical requirements for PTH is also a priority. In the longer term, re-standardization of PTH methods in terms of an appropriate International Standard is required. Provided commutability can be demonstrated, the recently established IS 95/646 for PTH (1-84) is a suitable candidate. Establishment of a well-characterized panel of samples of defined clinical provenance to enable manufacturers to determine appropriate reference intervals and clinical decision points is also recommended and will provide an invaluable clinical resource. Recent developments in mass spectrometry mean that a candidate reference measurement procedure for PTH is now achievable and will represent major progress. Concurrently, evidence-based recommendations on clinical requirements and performance goals for PTH are required. Improving the comparability of PTH results requires support from many stakeholders but is achievable.
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Garrett G, Sardiwal S, Lamb EJ, Goldsmith DJA. PTH--a particularly tricky hormone: why measure it at all in kidney patients? Clin J Am Soc Nephrol 2012; 8:299-312. [PMID: 22403273 DOI: 10.2215/cjn.09580911] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Plasma parathyroid hormone (PTH) concentrations are commonly measured in the context of CKD, as PTH concentration elevation is typical in this clinical context. Much has been inferred from this raised PTH concentration tendency, both about the state of skeletal integrity and health and also about the potential clinical outcomes for patients. However, we feel that reliance on PTH concentrations alone is a dangerous substitute for the search for, and use of, more precise and reliable biomarkers. In this article, we rehearse these arguments, bringing together patient-level and analytical considerations for the first time.
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Affiliation(s)
- Giorgia Garrett
- East Kent Hospitals University, NHS Foundation Trust, Canterbury, Kent, United Kingdom
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Winkelmayer WC, Weiner DE. Commentary on ‘The DOPPS Practice Monitor for US Dialysis Care: Trends Through April 2011’: No Surprises Yet. Am J Kidney Dis 2012; 59:312-4. [DOI: 10.1053/j.ajkd.2011.11.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2011] [Accepted: 11/05/2011] [Indexed: 11/11/2022]
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Correale M. Parathyroid hormone measurement in chronic kidney disease--an evolving issue for the nephrologist and the clinical laboratorist: minireview. Immunopharmacol Immunotoxicol 2012; 34:541-7. [PMID: 22208997 DOI: 10.3109/08923973.2011.637501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Parathyroid hormone (PTH) is the polypeptide hormone produced by the parathyroid glands, which plays a central role in calcium homeostasis. Circulating PTH must be measured regularly in patients with chronic kidney disease (CKD)--mineral and bone disorders (MBD) to monitor and to adapt treatment with the aim of maintaining PTH levels within a defined narrow range of optimal values for each stage of CKD. Often, for the nephrologists, it is not easy to determine what PTH levels are clinically appropriate. Moreover, the PTH determination also shows many criticisms from the laboratory point of view and there is a clear need to standardize PTH measurements in every phase of the process: pre-analytical, analytical and post-analytical. In this review, all these aspects are summarized with particular reference to the most recent opportunities to improve PTH assays quality on the whole. To this aim, a closer cooperation between nephrologists and clinical laboratories is undoubtedly necessary.
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Affiliation(s)
- Mario Correale
- Clinical Pathology Laboratory, IRCCS S. De Bellis Institute, Castellana Grotte-Bari, Italy.
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The Japanese Society for Dialysis Therapy. Clinical Practice Guideline for CKD-MBD. ACTA ACUST UNITED AC 2012. [DOI: 10.4009/jsdt.45.301] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Cavalier E, Delanaye P, Vranken L, Bekaert AC, Carlisi A, Chapelle JP, Souberbielle JC. Interpretation of serum PTH concentrations with different kits in dialysis patients according to the KDIGO guidelines: importance of the reference (normal) values. Nephrol Dial Transplant 2011; 27:1950-6. [PMID: 21940481 DOI: 10.1093/ndt/gfr535] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND The recommended target range for serum parathyroid hormone (PTH) in dialysis patients has changed from 150 to 300 pg/mL in the KDOQI guidelines to two to nine times the upper normal limit in the KDIGO ones. Although inclusion/exclusion criteria for the reference population are highly important, they are usually not mentioned in the commercial kits. In this study, we used the same reference population of vitamin D-replete normal subjects to establish reference values for 10 commercial PTH kits. We evaluated whether this may improve the classification of dialysis patients according to the KDIGO compared to the use of reference values proposed by the manufacturers. METHODS We measured serum PTH with 10 different kits in 149 haemodialysis patients, and 240 25-OH-vitamin D-replete (>75 nmol/L) individuals with an estimated glomerular filtration rate >60 mL/min/1.73 m(2). RESULTS For the 10 kits, our upper normal limit was lower than those of the manufacturers. The difference was, however, variable from one kit to another. The two kits that yielded the lowest and the highest absolute concentrations classified differently 84/149 patients (56.4%) according to the KDOQI and 53/149 (36.2%) according to the KDIGO using the manufacturers' normal values. Using our normal values significantly decreased the discrepancies with 24/149 patients (16.1%) being still classified differently. Taking the measurement uncertainty into consideration, 8% of the patients only remained differently classified by these two kits. CONCLUSIONS Using the same vitamin-D-replete population to establish the reference range for 10 commercial PTH kits significantly improved the classification of haemodialysis patients according to the KDIGO target range.
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Affiliation(s)
- Etienne Cavalier
- Department of Clinical Chemistry, University of Liège, CHU Sart-Tilman, Liège, Belgium.
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Komaba H, Kakuta T, Fukagawa M. Diseases of the parathyroid gland in chronic kidney disease. Clin Exp Nephrol 2011; 15:797-809. [DOI: 10.1007/s10157-011-0502-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2011] [Accepted: 07/08/2011] [Indexed: 12/31/2022]
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Morrone LF, Russo D, Di Iorio B. Diagnostic Workup for Disorders of Bone and Mineral Metabolism in Patients with Chronic Kidney Disease in the Era of KDIGO Guidelines. Int J Nephrol 2011; 2011:958798. [PMID: 21603118 PMCID: PMC3097081 DOI: 10.4061/2011/958798] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2010] [Accepted: 02/15/2011] [Indexed: 11/30/2022] Open
Abstract
KDIGO (Kidney Disease: Improving Global Outcomes) is an international nonprofit organization devoted to “improve the care and outcomes of kidney disease patients worldwide through promoting coordination, collaboration, and integration of initiatives to develop and implement clinical practice guidelines.” The mineral and bone disorder (MBD) in patients with chronic kidney disease (CKD) has been the first area of interest of KDIGO international initiative. KDIGO guidelines on CKD-MBD were published in 2009 with the intent to modify the previous KDOQI guidelines that had failed to consistently change the global outcome of CKD patients. After the publication of KDOQI guidelines for bone metabolism and disease in 2003, a large number of observational data emerged in literature linking disordered mineral metabolism with adverse clinical outcomes. Notwithstanding this large body of observational data, a paucity of evidence from high-quality clinical trials was available for the development of KDIGO guidelines. Herein, a summary will be provided of the most important findings of KDIGO guidelines regarding the diagnostic workup and clinical monitoring of CKD-MBD patients.
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West NE, Lechtzin N, Merlo CA, Turowski JB, Davis ME, Ramsay MZ, Watts SL, Stenner SP, Boyle MP. Appropriate goal level for 25-hydroxyvitamin D in cystic fibrosis. Chest 2011; 140:469-474. [PMID: 21393390 DOI: 10.1378/chest.10-2114] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Vitamin D deficiency is common in patients with cystic fibrosis (CF), and guidelines recommend 25-hydroxyvitamin D (25OHD) levels ≥ 30 ng/mL. This threshold was selected because serum parathyroid hormone (PTH) rises in healthy individuals when the 25OHD level falls below 30 ng/mL. PTH levels > 50 pg/mL are associated with an increased risk of bone loss. However, the relationship between 25OHD and PTH has not been studied in CF. We sought to determine the appropriate goal 25OHD level in patients with CF by identifying the level below which the risk of PTH > 50 pg/mL begins to increase. METHODS Levels of 25OHD and PTH in 216 individuals with CF were collected prospectively. Individuals with 25OHD < 30 ng/mL were treated with vitamin D2, and levels were reevaluated. RESULTS Mean 25OHD level was 25.7 ± 12.4 ng/mL, and mean PTH level was 46.7 ± 25.9 pg/mL. In 63% of individuals, 25OHD level was < 30 ng/mL, and in 38.0% it was ≤ 20 ng/mL. Low 25OHD levels were significantly associated with elevated PTH levels, with a mean PTH of 53.1 ± 29.8 pg/mL for 25OHD level 0 to 19 ng/mL; 51.1 ± 30.7 pg/mL for 25OHD level 20 to 29 ng/mL; 38.4 ± 16.4 pg/mL for 25OHD level 30 to 39 ng/mL; and 37.2 ± 16.4 pg/mL for 25OHD level ≥ 40 ng/mL (P = .006). We assessed the sensitivity of different 25OHD thresholds to identify individuals meeting the goal of a PTH level < 50 pg/mL to reduce the risk of bone loss. To obtain 90% sensitivity, a 25OHD level ≥ 35 ng/mL was required. Strikingly, 23% of individuals with 25OHD levels 30 to 34 ng/mL still had a PTH level > 50 pg/mL. This decreased to 14% for 25OHD level ≥ 35 ng/mL. CONCLUSIONS Inadequate serum 25OHD levels are common in adults with CF and are associated with elevated PTH levels. Aiming to maintain 25-OHD levels ≥ 35 ng/mL in individuals with CF decreases the risk of having a PTH level associated with secondary hyperparathyroidism and bone loss.
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Affiliation(s)
- Natalie E West
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University, Baltimore, MD.
| | - Noah Lechtzin
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University, Baltimore, MD
| | - Christian A Merlo
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University, Baltimore, MD
| | - Jason B Turowski
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Marsha E Davis
- Department of Nutrition, Johns Hopkins University, Baltimore, MD
| | - Meghan Z Ramsay
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University, Baltimore, MD
| | - Sharon L Watts
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University, Baltimore, MD
| | - Shane P Stenner
- Department of Medicine, Vanderbilt University, Nashville, TN
| | - Michael P Boyle
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University, Baltimore, MD
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Fotheringham J, Balasubramanian SP, Harrison B, Wilkie M. Post-Parathyroidectomy Parathyroid Hormone Levels: The Impact on Patient Survival – A Single-Centre Study in a Stage 5 Chronic Kidney Disease Population. ACTA ACUST UNITED AC 2011; 119:c113-20. [DOI: 10.1159/000326683] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 02/16/2011] [Indexed: 11/19/2022]
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La’ulu SL, Roberts WL. Performance characteristics of six intact parathyroid hormone assays. Am J Clin Pathol 2010; 134:930-8. [PMID: 21088157 DOI: 10.1309/ajcplgczr7ipvha7] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
The aim of this study was to evaluate the performance characteristics of 6 intact parathyroid hormone assays: Access 2 (Beckman Coulter, Fullerton, CA), ARCHITECT i2000(SR) (Abbott Diagnostics, Abbott Park, IL), ADVIA Centaur (Siemens Healthcare Diagnostics, Deerfield, IL), Modular E170 (Roche Diagnostics, Indianapolis, IN), IMMULITE 2000 (Siemens Healthcare Diagnostics), and LIAISON (DiaSorin, Stillwater, MN). Sample collection tubes and storage conditions were compared. Imprecision studies were performed using commercial quality control materials. Linearity was assessed using pools prepared from samples. For method comparison, serum and EDTA plasma samples were tested by all methods, and the ARCHITECT was used as the comparison method. Reference intervals were determined using various vitamin D cutoffs. The types of collection tubes and storage conditions are more important for some methods than others. Total coefficients of variation were 10.9% or less. The maximum deviation from the target recovery for linearity ranged from 5.0% to 82.2%. Bland-Altman plots demonstrated percentage biases ranging from -36.3% to 24.4%. The lower limit of the reference interval was not influenced by vitamin D status, whereas the upper reference limit was affected.
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Uhlig K, Berns JS, Kestenbaum B, Kumar R, Leonard MB, Martin KJ, Sprague SM, Goldfarb S. KDOQI US commentary on the 2009 KDIGO Clinical Practice Guideline for the Diagnosis, Evaluation, and Treatment of CKD-Mineral and Bone Disorder (CKD-MBD). Am J Kidney Dis 2010; 55:773-99. [PMID: 20363541 DOI: 10.1053/j.ajkd.2010.02.340] [Citation(s) in RCA: 176] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Accepted: 02/16/2010] [Indexed: 02/08/2023]
Abstract
This commentary provides a US perspective on the 2009 KDIGO (Kidney Disease: Improving Global Outcomes) Clinical Practice Guideline for the Diagnosis, Evaluation, Prevention, and Treatment of Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD). KDIGO is an independent international organization with the primary mission of the promotion, coordination, collaboration, and integration of initiatives to develop and implement clinical practice guidelines for the care of patients with kidney disease. The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI), recognizing that international guidelines need to be adapted for each country, convened a group of experts to comment on the application and implementation of the KDIGO guideline for patients with CKD in the United States. This commentary puts the KDIGO guideline into the context of the supporting evidence and the setting of care delivered in the United States and summarizes important differences between prior KDOQI guidelines and the newer KDIGO guideline. It also considers the potential impact of a new bundled payment system for dialysis clinics. The KDIGO guideline addresses the evaluation and treatment of abnormalities of CKD-MBD in adults and children with CKD stages 3-5 on long-term dialysis therapy or with a kidney transplant. Tests considered are those that relate to laboratory, bone, and cardiovascular abnormality detection and monitoring. Treatments considered are interventions to treat hyperphosphatemia, hyperparathyroidism, and bone disease in patients with CKD stages 3-5D and 1-5T. Limitations of the evidence are discussed. The lack of definitive clinical outcome trials explains why most recommendations are not of level 1 but of level 2 strength, which means weak or discretionary recommendations. Suggestions for future research highlight priority areas.
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Affiliation(s)
- Katrin Uhlig
- Tufts Medical Center, Tufts University School of Medicine, Boston MA, USA
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Herberth J, Branscum AJ, Mawad H, Cantor T, Monier-Faugere MC, Malluche HH. Intact PTH combined with the PTH ratio for diagnosis of bone turnover in dialysis patients: a diagnostic test study. Am J Kidney Dis 2010; 55:897-906. [PMID: 20347512 DOI: 10.1053/j.ajkd.2009.12.041] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Accepted: 12/21/2009] [Indexed: 11/11/2022]
Abstract
BACKGROUND Determination of parathyroid hormone (PTH) level is the most commonly used surrogate marker for bone turnover in patients with stage 5 chronic kidney disease on dialysis therapy (CKD-5D). The objective of this study is to evaluate the predictive value of various PTH measurements for identifying low or high bone turnover rate. STUDY DESIGN Diagnostic test study. SETTINGS & PARTICIPANTS 141 patients with CKD-5D from 15 US hemodialysis centers. INDEX TESTS Intact PTH, PTH 1-84, and PTH ratio (ratio of level of PTH 1-84 to level of large carboxy-terminal PTH fragments). REFERENCE TEST OR OUTCOME Bone turnover determined using bone histomorphometry. OTHER MEASUREMENTS Demographic and treatment-related factors, serum calcium and phosphorus. RESULTS Patients presented histologically with a broad range of bone turnover abnormalities. In white patients with CKD-5D (n = 70), PTH ratio <1.0 added to intact PTH level <420 pg/mL increased the positive predictive value for low bone turnover from 74% to 90%. In black patients (n = 71), adding PTH ratio <1.2 to intact PTH level <340 pg/mL increased the positive predictive value for low bone turnover from 48% to 90%. Adding PTH ratio >1.6 to intact PTH level of 340-790 pg/mL increased the positive predictive value for high bone turnover from 56% to 71%. LIMITATIONS Because the research protocol called for carefully controlled blood specimen handling, blood drawing and routine specimen handling might be less stringent in clinical practice. By limiting study participation to black and white patients with CKD-5D, we cannot comment on the roles of intact PTH, PTH 1-84, and PTH ratio in other racial/ethnic groups. CONCLUSION In black patients with CKD-5D, the addition of PTH ratio to intact PTH measurements is helpful for diagnosing low and high bone turnover. In white patients with CKD-5D, it aids in the diagnosis of low bone turnover.
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Affiliation(s)
- Johann Herberth
- Division of Nephrology, Bone and Mineral Metabolism, University of Kentucky, Lexington, KY, USA
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Souberbielle JC, Cavalier E, Jean G. Interpretation of serum parathyroid hormone concentrations in dialysis patients: what do the KDIGO guidelines change for the clinical laboratory? Clin Chem Lab Med 2010; 48:769-74. [DOI: 10.1515/cclm.2010.157] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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45
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Bowen RAR, Hortin GL, Csako G, Otañez OH, Remaley AT. Impact of blood collection devices on clinical chemistry assays. Clin Biochem 2009; 43:4-25. [PMID: 19822139 DOI: 10.1016/j.clinbiochem.2009.10.001] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Revised: 09/30/2009] [Accepted: 10/02/2009] [Indexed: 11/29/2022]
Abstract
Blood collection devices interact with blood to alter blood composition, serum, or plasma fractions and in some cases adversely affect laboratory tests. Vascular access devices may release coating substances and exert shear forces that lyse cells. Blood-dissolving tube additives can affect blood constituent stability and analytical systems. Blood tube stoppers, stopper lubricants, tube walls, surfactants, clot activators, and separator gels may add materials, adsorb blood components, or interact with protein and cellular components. Thus, collection devices can be a major source of preanalytical error in laboratory testing. Device manufacturers, laboratory test vendors, and clinical laboratory personnel must understand these interactions as potential sources of error during preanalytical laboratory testing. Although the effects of endogenous blood substances have received attention, the effects of exogenous substances on assay results have not been well described. This review will identify sources of exogenous substances in blood specimens and propose methods to minimize their impact on clinical chemistry assays.
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Affiliation(s)
- Raffick A R Bowen
- Department of Pathology, Stanford University, 300 Pasteur Drive, Room H1507 B, Stanford, CA 94305, USA.
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Cavalier E, Delanaye P, Hubert P, Krzesinski JM, Chapelle JP, Rozet E. Estimation of the stability of parathyroid hormone when stored at -80 degrees C for a long period. Clin J Am Soc Nephrol 2009; 4:1988-92. [PMID: 19820128 DOI: 10.2215/cjn.03970609] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND OBJECTIVES Stability of parathyroid hormone (PTH) at -80 degrees C for long storage periods has never been studied. This can be of importance for the conclusions of studies where blood banks have been constituted. The study's aim was to evaluate stability of PTH when stored as serum or plasma EDTA samples at -80 degrees C. DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS Samples were collected from 16 chronic hemodialysis patients using EDTA and gel-separator tubes. Plasma and serum were aliquoted; one aliquot was assayed with Elecsys and Liaison methods to determine the "baseline" values and another aliquot after 1, 3, 6, and 12 mo. The factors "method," "tubes," "subjects," and "time" were included in a mixed linear model to evaluate their effects on measured PTH values. The prediction interval methodology was used to assess where a future result could be obtained with a defined probability. RESULTS With the Liaison method, the maximum storage times with either dry or EDTA tubes were estimated to be 9 and 2 mo, respectively. With the Elecsys method, samples could be stored at least 2 yr with acceptable level of degradation. CONCLUSION PTH stability at -80 degrees C is not infinite. Maximum storage time and acceptance limits (30%) were defined, showing that with one method, samples should be stored for not more than 2 mo, whereas the other could be stored for up to 2 yr. With any PTH assay, the maximum storage time should be evaluated to ascertain that samples will keep their initial reactive profile after prolonged storage periods.
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Affiliation(s)
- Etienne Cavalier
- Department of Clinical Chemistry, University of Liège, Domaine du Sart-Tilman, Liège, Belgium.
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LEVITT H, SMITH KG, ROSNER MH. Variability in calcium, phosphorus, and parathyroid hormone in patients on hemodialysis. Hemodial Int 2009; 13:518-25. [DOI: 10.1111/j.1542-4758.2009.00393.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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The five most commonly used intact parathyroid hormone assays are useful for screening but not for diagnosing bone turnover abnormalities in CKD-5 patients. Clin Nephrol 2009; 72:5-14. [PMID: 19640382 DOI: 10.5414/cnp72005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND/AIMS Assessment of bone turnover for management of renal osteodystrophy is part of routine care in chronic kidney disease Stage 5 (CKD-5) patients. Measurement of intact parathyroid hormone (iPTH) is the most commonly used surrogate marker for bone turnover in these patients. The current study was conducted to evaluate the predictive value of the five most commonly used iPTH assays for bone turnover. METHODS In a cross-sectional study, 84 CKD-5 patients underwent bone biopsy and blood drawings for determination of iPTH and total serum alkaline phosphatase (AP). RESULTS Histologically, patients presented with a broad range of bone turnover abnormalities as determined by activation frequency and bone formation rate/bone surface. Results of the five iPTH assays in each patient correlated but were significantly different. There were also significant differences between iPTH measurements at the same bone turnover level. Using Kidney Disease Outcome Quality Initiative recommended iPTH ranges, all assays showed comparably poor diagnostic performance. At 80% specificity, cut-off values of the 5 iPTH assays for low bone turnover varied from 165 to 550 pg/ml and for high bone turnover from 404 to 1,003 pg/ml. Sensitivities at these cutoffs remained below acceptable standards. Addition of AP measurements to iPTH did not improve diagnostic accuracy. CONCLUSIONS Precise assessment of bone turnover will require utilization of established and novel bone markers reflecting effects of bone turnover rather than measuring only iPTH or other effectors.
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Monge M, Jean G, Bacri JL, Lemaitre V, Masy E, Joly D, Souberbielle JC. Higher parathyroid hormone (PTH) concentrations with the Architect PTH assay than with the Elecsys assay in hemodialysis patients, and a simple way to standardize these two methods. Clin Chem Lab Med 2009; 47:362-6. [PMID: 19199835 DOI: 10.1515/cclm.2009.068] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines recommend maintaining serum parathyroid hormone (PTH) concentration between 150 and 300 pg/mL in patients with chronic kidney disease (CKD) stage 5. However, a marked inter-method variability in PTH measurement has been reported recently. The aim of this study was to evaluate whether harmonization of the results measured with two commercial kits known to produce significantly different serum PTH concentrations could be reasonably achieved by a simple procedure. METHODS The study comprised a total of 216 hemodialyzed patients in whom blood was collected immediately before a dialysis session. The patients were from three dialysis centers, which defined three groups (119, 34, and 63 patients for groups 1, 2, and 3, respectively). PTH was measured by two automated assays, the Elecsys (Roche Diagnostics) and Architect (Abbott Diagnostics) assays, in three different laboratories and with different lots of reagents. We arbitrarily chose the Roche assay as the reference method, because several studies had previously shown that the concentrations measured with this assay were very close to the Allegro assay used in the studies that defined the K/DOQI thresholds. Data are median (interquartile range). RESULTS The median PTH concentrations were higher (p<0.001) in the Architect assay [238 (140-434) pg/mL] when compared to the Elecsys assay [182 (109-338) pg/mL]. Bland-Altman plots in the three groups showed a similar proportional bias between both kits. The Architect PTH/Elecsys PTH ratios were similar in the three groups [1.30 (1.25-1.35), 1.30 (1.19-1.39), and 1.31 (1.25-1.35)], and the ratio was 1.30 (1.25-1.35) in the cohort (pooling the three groups). In the whole population, 53 patients (24.5%) were classified differently by the two kits according to the K/DOQI cut-off values. We divided the Architect values by 1.3 to obtain "corrected" values. These corrected Architect values were not different to the measured Elecsys values, and the Bland-Altman plot comparing the Elecsys and the corrected Artchitect values did not show any systematic proportional bias. Only six patients (2.8%) were still classified differently by the Elecsys and the corrected Architect concentrations. CONCLUSIONS We propose to divide the PTH values measured with the Architect PTH assay by 1.3 so that the corrected values are almost identical to those measured with the Elecsys assay.
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Affiliation(s)
- Marie Monge
- Laboratoire Pasteur Cerba, Saint-Ouen L'Aumone, France
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