Home Short- and long-term biological variation of cardiac troponin I in healthy individuals, and patients with end-stage renal failure requiring haemodialysis or cardiomyopathy
Article
Licensed
Unlicensed Requires Authentication

Short- and long-term biological variation of cardiac troponin I in healthy individuals, and patients with end-stage renal failure requiring haemodialysis or cardiomyopathy

  • Nick S. R. Lan , Lan T. Nguyen , Samuel D. Vasikaran , Catherine Wilson , Jacqueline Jonsson , James M. Rankin and Damon A. Bell EMAIL logo
Published/Copyright: June 29, 2020
Become an author with De Gruyter Brill
Submit Manuscript Author Information
Clinical Chemistry and Laboratory Medicine (CCLM)
From the journal Clinical Chemistry and Laboratory Medicine (CCLM) Volume 58 Issue 11

Abstract

Objectives

High-sensitivity (hs) cardiac troponin (cTn) assays can quantitate small fluctuations in cTn concentration. Determining biological variation allows calculation of reference change values (RCV), to define significant changes. We assessed the short- and long-term biological variation of cardiac troponin I (cTnI) in healthy individuals and patients with renal failure requiring haemodialysis or cardiomyopathy.

Methods

Plasma samples were collected hourly for 4 h and weekly for seven further weeks from 20 healthy individuals, 9 renal failure patients and 20 cardiomyopathy patients. Pre- and post-haemodialysis samples were collected weekly for 7 weeks. Samples were analysed using a hs-cTnI assay (Abbott Alinity ci-series). Within-subject biological variation (CVI), analytical variation (CVA) and between-subject biological variation (CVG) was used to calculate RCVs and index of individuality (II).

Results

For healthy individuals, CVI, CVA, CVG, RCV and II values were 8.8, 14.0, 43.1, 45.8% and 0.38 respectively for short-term, and 41.4, 14.0, 25.8, 121.0% and 1.69 for long-term. For renal failure patients, these were 2.6, 5.8, 50.5, 17.6% and 0.30 respectively for short-term, and 19.1, 5.8, 11.2, 55.2% and 1.78 for long-term. For cardiomyopathy patients, these were 4.2, 10.0, 65.9, 30.0% and 0.16 respectively for short-term, and 17.5, 10.0, 63.1, 55.8% and 0.32 for long-term. Mean cTnI concentration was lower post-haemodialysis (15.2 vs. 17.8 ng/L, p < 0.0001), with a 16.9% mean relative change.

Conclusions

The biological variation of cTnI is similar between end-stage renal failure and cardiomyopathy patients, but proportionately greater in well-selected healthy individuals with very low baseline cTnI concentrations.

Keywords: biochemistry; biological variation; myocardial infarct; troponin
Corresponding author: A/Prof. Damon A. Bell, Department of Clinical Biochemistry, PathWest Laboratory Medicine, Fiona Stanley Hospital, 11 Robin Warren Drive, Murdoch, Western Australia, 6150, Australia; Medical School, The University of Western Australia, Perth, Western Australia, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Fiona Stanley Hospital, Perth, Western Australia, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth, Western Australia, Australia; Department of Cardiology, Lipid Disorders Clinic, Royal Perth Hospital, Perth, Western Australia, Australia; and Department of Clinical Biochemistry, Clinipath Pathology, Perth, Western Australia, Australia, E-mail:

Acknowledgments

We acknowledge all participants for providing plasma samples and staff from the phlebotomy service, the dialysis unit and the PathWest Laboratory, who assisted in the study conduct. Furthermore, we acknowledge Abbott Diagnostics, who provided the cardiac troponin kits, but did not have any role in the study design, collection, analysis, and interpretation of data, nor in writing the report or the decision to submit the report for publication.

  1. Research funding: None declared.

  2. Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  3. Competing interests: Abbott Diagnostics provided the cardiac troponin kits, but did not have any role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication. Authors state no conflict of interest.

  4. Informed consent: Informed consent was obtained from all individuals included in this study.

  5. Ethical approval: Ethical approval was obtained from the Human Research Ethics Committee (number: EMHS-2016-110).

References

1. Thygesen, K, Alpert, JS, Jaffe, AS, Chaitman, BR, Bax, JJ, Morrow, DA, et al. Fourth universal definition of myocardial infarction. J Am Coll Cardiol 2018;72:2231–64. https://doi.org/10.1016/j.jacc.2018.08.1038.Search in Google Scholar PubMed

2. Nomenclature and criteria for diagnosis of ischemic heart disease. Report of the Joint International Society and Federation of Cardiology/World Health Organization task force on standardization of clinical nomenclature. Circulation 1979;59:607–9. https://doi.org/10.1161/01.CIR.59.3.607.Search in Google Scholar

3. Wu, AH, Jaffe, AS, Apple, FS, Jesse, RL, Francis, GL, Morrow, DA, et al. National Academy of Clinical Biochemistry laboratory medicine practice guidelines: use of cardiac troponin and B-type natriuretic peptide or N-terminal proB-type natriuretic peptide for etiologies other than acute coronary syndromes and heart failure. Clin Chem 2007;53:2086–96. https://doi.org/10.1373/clinchem.2007.095679.Search in Google Scholar PubMed

4. Khalili, H, de Lemos, JA. What constitutes a relevant change in high-sensitivity troponin values over serial measurement? Clin Chem 2014;60:803–5. https://doi.org/10.1373/clinchem.2014.223669.Search in Google Scholar PubMed

5. Lan, NSR, Bell, DA. Revisiting the biological variability of cardiac troponin: implications for clinical practice. Clin Biochem Rev 2019;40:201–16.10.33176/AACB-19-00032Search in Google Scholar PubMed PubMed Central

6. Fraser, CG. Biological variation: from principles to practice. Washington, DC: AACC Press; 2001.Search in Google Scholar

7. Herman, DS, Kavsak, PA, Greene, DN. Variability and error in cardiac troponin testing: an ACLPS critical review. Am J Clin Pathol 2017;148:281–95. https://doi.org/10.1093/ajcp/aqx066.Search in Google Scholar PubMed

8. Lippi, G, Guidi, GC, Mattiuzzi, C, Plebani, M. Preanalytical variability: the dark side of the moon in laboratory testing. Clin Chem Lab Med 2006;44:358–65. https://doi.org/10.1515/cclm.2006.073.Search in Google Scholar

9. Apple, FS, Sandoval, Y, Jaffe, AS, Ordonez-Llanos, J. Cardiac troponin assays: guide to understanding analytical characteristics and their impact on clinical care. Clin Chem 2017;63:73–81. https://doi.org/10.1373/clinchem.2016.255109.Search in Google Scholar PubMed

10. Wu, AH. Biological and analytical variation of clinical biomarker testing: implications for biomarker-guided therapy. Curr Heart Fail Rep 2013;10:434–40. https://doi.org/10.1007/s11897-013-0156-6.Search in Google Scholar PubMed

11. Fraser, CG, Harris, EK. Generation and application of data on biological variation in clinical chemistry. Crit Rev Clin Lab Sci 1989;27:409–37. https://doi.org/10.3109/10408368909106595.Search in Google Scholar PubMed

12. White, HD. Pathobiology of troponin elevations: do elevations occur with myocardial ischemia as well as necrosis? J Am Coll Cardiol 2011;57:2406–8. https://doi.org/10.1016/j.jacc.2011.01.029.Search in Google Scholar PubMed

13. Hickman, PE, Potter, JM, Aroney, C, Koerbin, G, Southcott, E, Wu, AH, et al. Cardiac troponin may be released by ischemia alone, without necrosis. Clin Chim Acta 2010;411:318–23. https://doi.org/10.1016/j.cca.2009.12.009.Search in Google Scholar PubMed

14. Jacobs, LH, van de Kerkhof, J, Mingels, AM, Kleijnen, VW, van der Sande, FM, Wodzig, WK, et al. Haemodialysis patients longitudinally assessed by highly sensitive cardiac troponin T and commercial cardiac troponin T and cardiac troponin I assays. Ann Clin Biochem 2009;46:283–90. https://doi.org/10.1258/acb.2009.008197.Search in Google Scholar PubMed

15. Kociol, RD, Pang, PS, Gheorghiade, M, Fonarow, GC, O’Connor, CM, Felker, GM. Troponin elevation in heart failure prevalence, mechanisms, and clinical implications. J Am Coll Cardiol 2010;56:1071–8. https://doi.org/10.1016/j.jacc.2010.06.016.Search in Google Scholar PubMed

16. Aakre, KM, Roraas, T, Petersen, PH, Svarstad, E, Sellevoll, H, Skadberg, O, et al. Weekly and 90-minute biological variations in cardiac troponin T and cardiac troponin I in hemodialysis patients and healthy controls. Clin Chem 2014;60:838–47. https://doi.org/10.1373/clinchem.2013.216978.Search in Google Scholar PubMed

17. Nordenskjold, AM, Ahlstrom, H, Eggers, KM, Frobert, O, Jaffe, AS, Venge, P, et al. Short- and long-term individual variation in cardiac troponin in patients with stable coronary artery disease. Clin Chem 2013;59:401–9. https://doi.org/10.1373/clinchem.2012.191700.Search in Google Scholar PubMed

18. Roffi, M, Patrono, C, Collet, JP, Mueller, C, Valgimigli, M, Andreotti, F, et al. 2015 ESC guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation: task force for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation of the European Society of Cardiology (ESC). Eur Heart J 2016;37:267–315. https://doi.org/10.1093/eurheartj/ehv320.Search in Google Scholar PubMed

19. Wu, AH, Lu, QA, Todd, J, Moecks, J, Wians, F. Short- and long-term biological variation in cardiac troponin I measured with a high-sensitivity assay: implications for clinical practice. Clin Chem 2009;55:52–8. https://doi.org/10.1373/clinchem.2008.107391.Search in Google Scholar PubMed

20. Sherwood, MW, Kristin Newby, L. High-sensitivity troponin assays: evidence, indications, and reasonable use. J Am Heart Assoc 2014;3:e000403. https://doi.org/10.1161/jaha.113.000403.Search in Google Scholar

21. Wayand, D, Baum, H, Schatzle, G, Scharf, J, Neumeier, D. Cardiac troponin T and I in end-stage renal failure. Clin Chem 2000;46:1345–50. https://doi.org/10.1093/clinchem/46.9.1345.Search in Google Scholar

22. Lippi, G, Tessitore, N, Montagnana, M, Salvagno, GL, Lupo, A, Guidi, GC. Influence of sampling time and ultrafiltration coefficient of the dialysis membrane on cardiac troponin I and T. Arch Pathol Lab Med 2008;132:72–6.10.5858/2008-132-72-IOSTAUSearch in Google Scholar PubMed

23. Conway, B, McLaughlin, M, Sharpe, P, Harty, J. Use of cardiac troponin T in diagnosis and prognosis of cardiac events in patients on chronic haemodialysis. Nephrol Dial Transplant 2005;20:2759–64. https://doi.org/10.1093/ndt/gfi125.Search in Google Scholar PubMed

24. Hassan, HC, Howlin, K, Jefferys, A, Spicer, ST, Aravindan, AN, Suryanarayanan, G, et al. High-sensitivity troponin as a predictor of cardiac events and mortality in the stable dialysis population. Clin Chem 2014;60:389–98. https://doi.org/10.1373/clinchem.2013.207142.Search in Google Scholar PubMed

25. Pilbeam, V, Ridoutt, L, Badrick, T Best practice pathology collection in Australia. Asia Pac J Health Manag 2016;11:50–5. https://doi.org/10.24083/apjhm.v11i1.243.Search in Google Scholar

26. Fokkema, MR, Herrmann, Z, Muskiet, FA, Moecks, J. Reference change values for brain natriuretic peptides revisited. Clin Chem 2006;52:1602–3. https://doi.org/10.1373/clinchem.2006.069369.Search in Google Scholar PubMed

27. Apple, FS, Murakami, MM, Wians, FH, Ler, K, Kaczmarek, JM, Wu, AHB. Short-term biological variation of cardiac troponin I measured with three high-sensitivity assays. Clin Chem 2011;57:C05.Search in Google Scholar

28. Goldberg, J, Iriarte, B, Prostko, J, Frias, E, Ravalico, T, Hebbar, S. Short and long-term biological variability of troponin I determined using the ARCHITECT STAT high sensitive troponin I assay. Clin Chem 2011;57:C04.Search in Google Scholar

29. van der Linden, N, Hilderink, JM, Cornelis, T, Kimenai, DM, Klinkenberg, LJJ, van Doorn, WP, et al. Twenty-four-hour biological variation profiles of cardiac troponin I in individuals with or without chronic kidney disease. Clin Chem 2017;63:1655–6. https://doi.org/10.1373/clinchem.2017.275107.Search in Google Scholar PubMed

30. Vasile, VC, Saenger, AK, Kroning, JM, Klee, GG, Jaffe, AS. Biologic variation of a novel cardiac troponin I assay. Clin Chem 2011;57:1080–1. https://doi.org/10.1373/clinchem.2011.162545.Search in Google Scholar PubMed

31. Roraas, T, Stove, B, Petersen, PH, Sandberg, S Biological variation: the effect of different distributions on estimated within-person variation and reference change values. Clin Chem 2016;62:725–6. https://doi.org/10.1373/clinchem.2015.252296.Search in Google Scholar PubMed

32. National Institute for Health and Care Excellence (NICE). Identification and management of familial hypercholesterolaemia. NICE clinical guideline addendum CG71. London: NICE; 2017.Search in Google Scholar

33. Mbagaya, W, Luvai, A, Lopez, B. Biological variation of cardiac troponin in stable haemodialysis patients. Ann Clin Biochem 2015;52:562–8. https://doi.org/10.1177/0004563215585877.Search in Google Scholar PubMed

34. Frankenstein, L, Remppis, A, Giannitis, E, Frankenstein, J, Hess, G, Zdunek, D, et al. Biological variation of high sensitive Troponin T in stable heart failure patients with ischemic or dilated cardiomyopathy. Clin Res Cardiol 2011;100:633–40. https://doi.org/10.1007/s00392-011-0285-4.Search in Google Scholar PubMed

35. Meijers, WC, van der Velde, AR, Muller Kobold, AC, Dijck-Brouwer, J, Wu, AH, Jaffe, A, et al. Variability of biomarkers in patients with chronic heart failure and healthy controls. Eur J Heart Fail 2017;19:357–65. https://doi.org/10.1002/ejhf.669.Search in Google Scholar PubMed PubMed Central

36. Peeters, F, Kietselaer, B, Hilderink, J, van der Linden, N, Niens, M, Crijns, H, et al. Biological variation of cardiac markers in patients with aortic valve stenosis. Open Heart 2019;6:e001040. https://doi.org/10.1136/openhrt-2019-001040.Search in Google Scholar PubMed PubMed Central

37. Schindler, EI, Szymanski, JJ, Hock, KG, Geltman, EM, Scott, MG. Short- and long-term biologic variability of Galectin-3 and other cardiac biomarkers in patients with stable heart failure and healthy adults. Clin Chem 2016;62:360–6. https://doi.org/10.1373/clinchem.2015.246553.Search in Google Scholar PubMed

38. Mueller, M, Biener, M, Vafaie, M, Doerr, S, Keller, T, Blankenberg, S, et al. Absolute and relative kinetic changes of high-sensitivity cardiac troponin T in acute coronary syndrome and in patients with increased troponin in the absence of acute coronary syndrome. Clin Chem 2012;58:209–18. https://doi.org/10.1373/clinchem.2011.171827.Search in Google Scholar PubMed

39. Reichlin, T, Irfan, A, Twerenbold, R, Reiter, M, Hochholzer, W, Burkhalter, H, et al. Utility of absolute and relative changes in cardiac troponin concentrations in the early diagnosis of acute myocardial infarction. Circulation 2011;124:136–45. https://doi.org/10.1161/circulationaha.111.023937.Search in Google Scholar PubMed

40. Simpson, AJ, Potter, JM, Koerbin, G, Oakman, C, Cullen, L, Wilkes, GJ, et al. Use of observed within-person variation of cardiac troponin in emergency department patients for determination of biological variation and percentage and absolute reference change values. Clin Chem 2014;60:848–54. https://doi.org/10.1373/clinchem.2013.219410.Search in Google Scholar PubMed

41. Irfan, A, Reichlin, T, Twerenbold, R, Meister, M, Moehring, B, Wildi, K, et al. Early diagnosis of myocardial infarction using absolute and relative changes in cardiac troponin concentrations. Am J Med 2013;126:781–8.e2. https://doi.org/10.1016/j.amjmed.2013.02.031.Search in Google Scholar PubMed

42. Chen, M, Gerson, H, Eintracht, S, Nessim, SJ, MacNamara, E. Effect of hemodialysis on levels of high-sensitivity cardiac Troponin T. Am J Cardiol 2017;120:2061–4. https://doi.org/10.1016/j.amjcard.2017.08.026.Search in Google Scholar PubMed

43. Skadberg, O, Sandberg, S, Roraas, T, Petersen, PH, Sellevoll, H, Svarstad, E, et al. The variation in high sensitive cardiac troponin concentration during haemodialysis treatment is not similar to the biological variation observed in stable end stage renal disease patients. Scand J Clin Lab Invest 2016;76:645–52. https://doi.org/10.1080/00365513.2016.1230886.Search in Google Scholar PubMed

44. Tarapan, T, Musikatavorn, K, Phairatwet, P, Takkavatakarn, K, Susantitaphong, P, Eiam-Ong, S, et al. High sensitivity Troponin-I levels in asymptomatic hemodialysis patients. Ren Fail 2019;41:393–400. https://doi.org/10.1080/0886022x.2019.1603110.Search in Google Scholar PubMed PubMed Central

45. Klinkenberg, LJ, van Dijk, JW, Tan, FE, van Loon, LJ, van Dieijen-Visser, MP, Meex, SJ. Circulating cardiac troponin T exhibits a diurnal rhythm. J Am Coll Cardiol 2014;63:1788–95. https://doi.org/10.1016/j.jacc.2014.01.040.Search in Google Scholar PubMed

46. Klinkenberg, LJ, Wildi, K, van der Linden, N, Kouw, IW, Niens, M, Twerenbold, R, et al. Diurnal rhythm of cardiac Troponin: consequences for the diagnosis of acute myocardial infarction. Clin Chem 2016;62:1602–11. https://doi.org/10.1373/clinchem.2016.257485.Search in Google Scholar PubMed

Received: 2020-01-15
Accepted: 2020-05-20
Published Online: 2020-06-29
Published in Print: 2020-10-25

© 2020 Walter de Gruyter GmbH, Berlin/Boston

Articles in the same Issue

  1. Frontmatter
  2. Editorial
  3. Biotin interference in cardiac troponin immunoassay – where the wild things are?
  4. Review
  5. Laboratory-related issues in the measurement of cardiac troponins with highly sensitive assays
  6. Mini Review
  7. Chromatographic methods development for clinical practice: requirements and limitations
  8. Opinion Paper
  9. Harmonising EQA schemes the next frontier: challenging the status quo
  10. Genetics and Molecular Diagnostics
  11. Direct comparison study between droplet digital PCR and a combination of allele-specific PCR, asymmetric rapid PCR and melting curve analysis for the detection of BRAF V600E mutation in plasma from melanoma patients
  12. A novel mitochondrial m.14430A>G (MT-ND6, p.W82R) variant causes complex I deficiency and mitochondrial Leigh syndrome
  13. Obesity status modifies the association between rs7556897T>C in the intergenic region SLC19A3-CCL20 and blood pressure in French children
  14. General Clinical Chemistry and Laboratory Medicine
  15. Influence of reagent lots and multiple measuring systems on estimating the coefficient of variation from quality control data; implications for uncertainty estimation and interpretation of QC results
  16. Electrophoretic α1-globulin for screening of α1-antitrypsin deficient variants
  17. A continued method performance monitoring approach for the determination of pediatric renin samples – application within a European clinical trial
  18. Pilot study for cystic fibrosis neonatal screening: the Cuban experience
  19. Validation of the analytical performance of the NOVEOS™ System, a system which improves upon the third-generation in vitro allergy testing technology
  20. IgE cross-reactivity measurement of cashew nut, hazelnut and peanut using a novel IMMULITE inhibition method
  21. Sexual dimorphism in the cerebrospinal fluid total protein content
  22. Current state of the morphological assessment of urinary erythrocytes in The Netherlands: a nation-wide questionnaire
  23. Reference Values and Biological Variations
  24. Within-subject and between-subject biological variation of first morning void urine amino acids in 12 healthy subjects
  25. Proenkephalin as a new biomarker for pediatric acute kidney injury – reference values and performance in children under one year of age
  26. Hematology and Coagulation
  27. Quality performance for indirect Xa inhibitor monitoring in patients using international external quality data
  28. Cardiovascular Diseases
  29. Clinical risk assessment of biotin interference with a high-sensitivity cardiac troponin T assay
  30. Short- and long-term biological variation of cardiac troponin I in healthy individuals, and patients with end-stage renal failure requiring haemodialysis or cardiomyopathy
  31. Infectious Diseases
  32. Monocyte distribution width (MDW) as a screening tool for sepsis in the Emergency Department
  33. Performance of a Toxo IgM prototype assay for the diagnosis of maternal and congenital Toxoplasma infections
  34. Letters to the Editors
  35. Evaluation of an ELISA for SARS-CoV-2 antibody testing: clinical performances and correlation with plaque reduction neutralization titer
  36. Preliminary evaluation of Roche Cobas Elecsys Anti-SARS-CoV-2 chemiluminescence immunoassay
  37. Hypoalbuminemia and elevated D-dimer in COVID-19 patients: a call for result harmonization
  38. Total pathway to method validation
  39. Derivation of performance specifications for uncertainty of serum C-reactive protein measurement according to the Milan model 3 (state of the art)
  40. FGF23 measurement in burosumab-treated patients: an emerging treatment may induce a new analytical interference
  41. Use of a modified IDS-ISYS intact PTH assay for intraoperative PTH measurements
  42. Agreement of dried blood spot lyso-Gb3 concentrations obtained from different laboratories in patients with Fabry disease
  43. Influence of delayed separation of plasma from whole blood and centrifugation protocol on Zn plasma concentration
  44. A survey of order of draw on inpatient wards and adherence to EFLM-COLABIOCLI recommendations
  45. Successful implementations of automated minimum re-test intervals to overcome ferritin over-requesting in a Spanish hospital laboratory
  46. Remarkable pseudoleucocytosis induced by mild cryoglobulinemia
  47. Massive hemolysis due to Clostridium perfringens: a laboratory’s perspective
https://doi.org/10.1515/cclm-2020-0046
Keywords for this article
biochemistry; biological variation; myocardial infarct; troponin

Articles in the same Issue

  1. Frontmatter
  2. Editorial
  3. Biotin interference in cardiac troponin immunoassay – where the wild things are?
  4. Review
  5. Laboratory-related issues in the measurement of cardiac troponins with highly sensitive assays
  6. Mini Review
  7. Chromatographic methods development for clinical practice: requirements and limitations
  8. Opinion Paper
  9. Harmonising EQA schemes the next frontier: challenging the status quo
  10. Genetics and Molecular Diagnostics
  11. Direct comparison study between droplet digital PCR and a combination of allele-specific PCR, asymmetric rapid PCR and melting curve analysis for the detection of BRAF V600E mutation in plasma from melanoma patients
  12. A novel mitochondrial m.14430A>G (MT-ND6, p.W82R) variant causes complex I deficiency and mitochondrial Leigh syndrome
  13. Obesity status modifies the association between rs7556897T>C in the intergenic region SLC19A3-CCL20 and blood pressure in French children
  14. General Clinical Chemistry and Laboratory Medicine
  15. Influence of reagent lots and multiple measuring systems on estimating the coefficient of variation from quality control data; implications for uncertainty estimation and interpretation of QC results
  16. Electrophoretic α1-globulin for screening of α1-antitrypsin deficient variants
  17. A continued method performance monitoring approach for the determination of pediatric renin samples – application within a European clinical trial
  18. Pilot study for cystic fibrosis neonatal screening: the Cuban experience
  19. Validation of the analytical performance of the NOVEOS™ System, a system which improves upon the third-generation in vitro allergy testing technology
  20. IgE cross-reactivity measurement of cashew nut, hazelnut and peanut using a novel IMMULITE inhibition method
  21. Sexual dimorphism in the cerebrospinal fluid total protein content
  22. Current state of the morphological assessment of urinary erythrocytes in The Netherlands: a nation-wide questionnaire
  23. Reference Values and Biological Variations
  24. Within-subject and between-subject biological variation of first morning void urine amino acids in 12 healthy subjects
  25. Proenkephalin as a new biomarker for pediatric acute kidney injury – reference values and performance in children under one year of age
  26. Hematology and Coagulation
  27. Quality performance for indirect Xa inhibitor monitoring in patients using international external quality data
  28. Cardiovascular Diseases
  29. Clinical risk assessment of biotin interference with a high-sensitivity cardiac troponin T assay
  30. Short- and long-term biological variation of cardiac troponin I in healthy individuals, and patients with end-stage renal failure requiring haemodialysis or cardiomyopathy
  31. Infectious Diseases
  32. Monocyte distribution width (MDW) as a screening tool for sepsis in the Emergency Department
  33. Performance of a Toxo IgM prototype assay for the diagnosis of maternal and congenital Toxoplasma infections
  34. Letters to the Editors
  35. Evaluation of an ELISA for SARS-CoV-2 antibody testing: clinical performances and correlation with plaque reduction neutralization titer
  36. Preliminary evaluation of Roche Cobas Elecsys Anti-SARS-CoV-2 chemiluminescence immunoassay
  37. Hypoalbuminemia and elevated D-dimer in COVID-19 patients: a call for result harmonization
  38. Total pathway to method validation
  39. Derivation of performance specifications for uncertainty of serum C-reactive protein measurement according to the Milan model 3 (state of the art)
  40. FGF23 measurement in burosumab-treated patients: an emerging treatment may induce a new analytical interference
  41. Use of a modified IDS-ISYS intact PTH assay for intraoperative PTH measurements
  42. Agreement of dried blood spot lyso-Gb3 concentrations obtained from different laboratories in patients with Fabry disease
  43. Influence of delayed separation of plasma from whole blood and centrifugation protocol on Zn plasma concentration
  44. A survey of order of draw on inpatient wards and adherence to EFLM-COLABIOCLI recommendations
  45. Successful implementations of automated minimum re-test intervals to overcome ferritin over-requesting in a Spanish hospital laboratory
  46. Remarkable pseudoleucocytosis induced by mild cryoglobulinemia
  47. Massive hemolysis due to Clostridium perfringens: a laboratory’s perspective
Sign up now to receive a 20% welcome discount
Institutional Access
How does access work?
Have an idea on how to improve our website?
Please write us.
© 2025 De Gruyter Brill
Downloaded on 15.9.2025 from https://www.degruyterbrill.com/document/doi/10.1515/cclm-2020-0046/html
Scroll to top button