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Kavsak PA, Ahmed B, Ivanick D, Greene DN, Ranjitkar P. Patient with macrocomplexes for both creatine kinase and cardiac troponin reveals the importance of immunoassay methods for macrotroponin detection. Clin Chim Acta 2024; 562:119885. [PMID: 39038589 DOI: 10.1016/j.cca.2024.119885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Revised: 07/16/2024] [Accepted: 07/19/2024] [Indexed: 07/24/2024]
Affiliation(s)
- Peter A Kavsak
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada.
| | - Basma Ahmed
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
| | | | - Dina N Greene
- University of Washington, Department of Laboratory Medicine and Pathology, Seattle, WA
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2
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Salaun E, Drory S, Coté M, Tremblay V, Bédard E, Steinberg C, Paré D, O'Connor K, Cieza T, Coté N, Poirier P, Douville P, Blais J, Desmeules P, Kalavrouziotis D, Mohammadi S, Voisine P, Bernier M, Pibarot P, Thériault S. Role of Antitroponin Antibodies and Macrotroponin in the Clinical Interpretation of Cardiac Troponin. J Am Heart Assoc 2024; 13:e035128. [PMID: 38879450 PMCID: PMC11255741 DOI: 10.1161/jaha.123.035128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/19/2024]
Abstract
Cardiac troponin is extensively used as a biomarker in modern medicine due to its diagnostic capability for myocardial injury, as well as its predictive and prognostic value for cardiac diseases. However, heterophile antibodies, antitroponin antibodies, and macrotroponin complexes can be observed both in seemingly healthy individuals and patients with cardiac diseases, potentially leading to false positive or disproportionate elevation of cTn (cardiac troponin) assay results and introducing discrepancies in clinical interpretations with impact on medical management. In this review article, we describe the possible mechanisms of cTn release and the sources of variations in the assessment of circulating cTn levels. We also explore the pathophysiological mechanisms underlying antitroponin antibody development and discuss the influence exerted by macrotroponin complexes on the results of immunoassays. Additionally, we explore approaches to detect these complexes by presenting various clinical scenarios encountered in routine clinical practice. Finally, unsolved questions about the development, prevalence, and clinical significance of cardiac autoantibodies are discussed.
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Affiliation(s)
- Erwan Salaun
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Samuel Drory
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Marc‐André Coté
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Veronic Tremblay
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Elisabeth Bédard
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Christian Steinberg
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - David Paré
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Kim O'Connor
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Tomas Cieza
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Nancy Coté
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Paul Poirier
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
- Faculty of pharmacyUniversité LavalQuébecCanada
| | - Pierre Douville
- Centre Hospitalier Universitaire de QuébecUniversité LavalQuébecCanada
| | - Jonatan Blais
- Centre Hospitalier Universitaire de QuébecUniversité LavalQuébecCanada
| | - Philippe Desmeules
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
- Centre Hospitalier Universitaire de QuébecUniversité LavalQuébecCanada
| | - Dimitris Kalavrouziotis
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Siamak Mohammadi
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Pierre Voisine
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
- Division of Cardiac SurgeryUniversity of Ottawa Heart InstituteOttawaOntarioCanada
| | - Mathieu Bernier
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Philippe Pibarot
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
| | - Sébastien Thériault
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité LavalQuébecCanada
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3
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Lam L, Kyle C. Practical approaches to the detection of macrotroponin. Ann Clin Biochem 2024; 61:122-132. [PMID: 37578158 DOI: 10.1177/00045632231197301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
INTRODUCTION Macrotroponin is increasingly recognised as a cause of confusion in interpreting high-sensitivity cardiac troponin (hs-cTnI) results. In this study, we sought to evaluate two practical approaches to detecting macrotroponin. These two approaches are PEG precipitation and SVM (support vector machine) analysis to classify discrepancies between hs-cTn assays. METHOD Residual serum and heparin plasma specimens (n = 483) with initially elevated hs-cTnI from hospital and community laboratories were retested on multiple hs-cTn platforms before and after PEG precipitation and Protein A immunoglobulin depletion. SVM analysis was conducted to identify a linear equation that best discriminated specimens with macrotroponin using a combination of results from two different hs-cTn assays. FINDINGS The diagnostic performance of PEG precipitation was carried out using Protein A immunoglobulin depletion as the reference comparator. When a cutoff residual activity after PEG precipitation of ≤ 20% was used, this threshold carried a high specificity of 92% (confidence interval 83-98%; n = 189) using the Siemens hs-cTnI Vista assay and 95% specificity (86%-98%; n = 242) using the Abbott hs-cTnI Architect assay. SVM analysis generated a linear equation identifying macrotroponin specimens from results obtained on two hs-cTn assays. This approach can be highly specific, comparable to PEG precipitation when certain assay combinations and concentrations are used. CONCLUSION We describe and identify practical alternatives to detecting macrotroponin. These approaches can be optimised for high specificity, reducing the need for more complex laboratory methods.
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Affiliation(s)
- Leo Lam
- Chemical Pathology, LabPlus, Auckland City Hospital, Auckland, New Zealand
- Biochemistry, Middlemore Hospital Laboratories, Auckland, New Zealand
| | - Campbell Kyle
- Chemical Pathology, LabPlus, Auckland City Hospital, Auckland, New Zealand
- Biochemistry, Labtests, Auckland, New Zealand
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4
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Meo L, Savarese M, Munno C, Mirabelli P, Ragno P, Leone O, Alfieri M. Circulating Biomarkers for Monitoring Chemotherapy-Induced Cardiotoxicity in Children. Pharmaceutics 2023; 15:2712. [PMID: 38140053 PMCID: PMC10747387 DOI: 10.3390/pharmaceutics15122712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 11/24/2023] [Accepted: 11/29/2023] [Indexed: 12/24/2023] Open
Abstract
Most commonly diagnosed cancer pathologies in the pediatric population comprise leukemias and cancers of the nervous system. The percentage of cancer survivors increased from approximatively 50% to 80% thanks to improvements in medical treatments and the introduction of new chemotherapies. However, as a consequence, heart disease has become the main cause of death in the children due to the cardiotoxicity induced by chemotherapy treatments. The use of different cardiovascular biomarkers, complementing data obtained from electrocardiogram, echocardiography cardiac imaging, and evaluation of clinical symptoms, is considered a routine in clinical diagnosis, prognosis, risk stratification, and differential diagnosis. Cardiac troponin and natriuretic peptides are the best-validated biomarkers broadly accepted in clinical practice for the diagnosis of acute coronary syndrome and heart failure, although many other biomarkers are used and several potential markers are currently under study and possibly will play a more prominent role in the future. Several studies have shown how the measurement of cardiac troponin (cTn) can be used for the early detection of heart damage in oncological patients treated with potentially cardiotoxic chemotherapeutic drugs. The advent of high sensitive methods (hs-cTnI or hs-cTnT) further improved the effectiveness of risk stratification and monitoring during treatment cycles.
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Affiliation(s)
- Luigia Meo
- Department of Chemistry and Biology, University of Salerno, Via Giovanni Paolo II, 132, 84084 Salerno, Italy; (L.M.); (P.R.)
| | - Maria Savarese
- Clinical Pathology, Santobono-Pausilipon Children’s Hospital, 80123 Naples, Italy; (M.S.); (C.M.); (O.L.)
| | - Carmen Munno
- Clinical Pathology, Santobono-Pausilipon Children’s Hospital, 80123 Naples, Italy; (M.S.); (C.M.); (O.L.)
| | - Peppino Mirabelli
- Clinical and Translational Research Unit, Santobono-Pausilipon Children’s Hospital, 80123 Naples, Italy;
| | - Pia Ragno
- Department of Chemistry and Biology, University of Salerno, Via Giovanni Paolo II, 132, 84084 Salerno, Italy; (L.M.); (P.R.)
| | - Ornella Leone
- Clinical Pathology, Santobono-Pausilipon Children’s Hospital, 80123 Naples, Italy; (M.S.); (C.M.); (O.L.)
| | - Mariaevelina Alfieri
- Clinical Pathology, Santobono-Pausilipon Children’s Hospital, 80123 Naples, Italy; (M.S.); (C.M.); (O.L.)
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van Avezaath LK, Nijenhuis HP, Muller Kobold AC. Unexpected high troponin T and I values in a child with hypertrophic cardiomyopathy and acute chest pain: a case report. Eur Heart J Case Rep 2023; 7:ytad375. [PMID: 37575535 PMCID: PMC10415857 DOI: 10.1093/ehjcr/ytad375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 07/13/2023] [Accepted: 07/31/2023] [Indexed: 08/15/2023]
Abstract
Background Elevated troponin T (cTnT) and/or troponin I (cTnI) can be ascribed to multiple causes, mostly resulting from cardiac tissue damage and in lesser numbers resulting from non-cardiac related causes. The presence of macrotroponins is easily overlooked, with potentially negative consequences. Case summary This case report presents a case study of a 12-year-old child known to have MYH7 gene-associated hypertrophic cardiomyopathy with acute chest pain combined with an unexpected high cTnT and cTnI. A cardiac cause was deemed unlikely after additional investigation, as these showed no abnormalities. After consulting a laboratory specialist, it could be concluded that the high cTnT and cTnI were a result of macrotroponin complexes, a protein complex consisting of circulating protein and endogenous autoantibodies against that protein, resulting in elevated values with misguiding and uncertain clinical significance. Discussion Awareness of the existence of macrotroponins could have prevented costly diagnostics and prolonged hospital admission with grave psychological impact, especially in children.
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Affiliation(s)
- Lisanne K van Avezaath
- Department of Pediatric Cardiology, University of Groningen, Beatrix Children Hospital, University Medical Center Groningen, Groningen, The Netherlands
| | - Hessel P Nijenhuis
- Department of Pediatric Cardiology, University of Groningen, Beatrix Children Hospital, University Medical Center Groningen, Groningen, The Netherlands
| | - Anneke C Muller Kobold
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, P.O. Box 30.001, 9700 RB Groningen, The Netherlands
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Hammarsten O, Warner JV, Lam L, Kavsak P, Lindahl B, Aakre KM, Collinson P, Jaffe AS, Saenger AK, Body R, Mills NL, Omland T, Ordonez-Llanos J, Apple FS. Antibody-mediated interferences affecting cardiac troponin assays: recommendations from the IFCC Committee on Clinical Applications of Cardiac Biomarkers. Clin Chem Lab Med 2023; 61:1411-1419. [PMID: 36952681 DOI: 10.1515/cclm-2023-0028] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 01/12/2023] [Indexed: 03/25/2023]
Abstract
The International Federation of Clinical Chemistry Committee on Clinical Applications of Cardiac Biomarkers (IFCC C-CB) provides educational documents to facilitate the interpretation and use of cardiac biomarkers in clinical laboratories and practice. Our aim is to improve the understanding of certain key analytical and clinical aspects of cardiac biomarkers and how these may interplay. Measurements of cardiac troponin (cTn) have a prominent place in the clinical work-up of patients with suspected acute coronary syndrome. It is therefore important that clinical laboratories know how to recognize and assess analytical issues. Two emerging analytical issues resulting in falsely high cTn concentrations, often several fold higher than the upper reference limit (URL), are antibody-mediated assay interference due to long-lived cTn-antibody complexes, called macrotroponin, and crosslinking antibodies that are frequently referred to as heterophilic antibodies. We provide an overview of antibody-mediated cTn assay interference and provide recommendations on how to confirm the interference and interpret the results.
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Affiliation(s)
- Ola Hammarsten
- Department of Clinical Chemistry and Transfusion Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Janet V Warner
- Faculty of Medicine, The University of Queensland, Saint Lucia, Australia
| | - Leo Lam
- Chemical Pathology, LabPlus, Auckland City Hospital, Auckland, New Zealand
- Biochemistry, Middlemore Hospital Laboratories, Auckland, New Zealand
| | - Peter Kavsak
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
| | - Bertil Lindahl
- Department of Medical Sciences, Uppsala University and Uppsala Clinical Research Center, Uppsala University, Uppsala, Sweden
| | - Kristin M Aakre
- Department of Medical Biochemistry and Pharmacology and Department of Heart Disease, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Paul Collinson
- Departments of Clinical Blood Sciences and Cardiology, St George's University Hospitals NHS Foundation Trust, London, UK
- St George's University of London, London, UK
| | - Allan S Jaffe
- Departments of Laboratory Medicine and Pathology and Cardiology, Mayo Clinic, Rochester, MN, USA
| | - Amy K Saenger
- Department of Laboratory Medicine and Pathology, Hennepin Healthcare/HCMC, Minneapolis, MN, USA
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, USA
| | - Richard Body
- Emergency Department, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
- Division of Cardiovascular Sciences, The University of Manchester, Manchester, UK
- Healthcare Sciences Department, Manchester Metropolitan University, Manchester, UK
| | - Nicholas L Mills
- BHF/University Centre for Cardiovascular Science and Usher Institute, University of Edinburgh, Edinburgh, UK
| | - Torbjørn Omland
- Department of Cardiology, Akershus University Hospital, Lørenskog, Norway
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Jordi Ordonez-Llanos
- Servicio de Bioquímica Clínica, Hospital de Sant Pau, Barcelona, Spain
- Foundation for the Biochemistry and Molecular Pathology, Barcelona, Spain
| | - Fred S Apple
- Department of Laboratory Medicine and Pathology, Hennepin Healthcare/HCMC, Minneapolis, MN, USA
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, USA
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Hammarsten O, Becker C, Engberg AE. Methods for analyzing positive cardiac troponin assay interference. Clin Biochem 2023; 116:24-30. [PMID: 36889375 DOI: 10.1016/j.clinbiochem.2023.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 02/28/2023] [Accepted: 03/03/2023] [Indexed: 03/08/2023]
Abstract
OBJECTIVES The cardiac damage biomarkers cardiac troponin T (cTnT) and troponin I (cTnI) are used to identify patients with myocardial infarction (MI). To make the correct clinical decisions it is important to identify false positive results due to troponin assay interference. Often interferences are caused by high-molecular weight immunocomplexes called macrotroponin that may result in false troponin elevations because of delayed troponin clearance, or heterophilic antibodies that crosslink troponin assay antibodies and generate troponin-independent signals. DESIGN & METHODS We describe and compare four methods for cTnI assay interference analysis using a protein G spin column method, gel filtration chromatography and two versions of a sucrose gradient ultracentrifugation for cTnI assay interference analysis on five patients with confirmed cTnI interference and one MI patient without cTnI interference from our troponin interference referral center. RESULTS The protein G spin column method had a high between run variability but was still able to identify all five patients with cTnI interference. The sucrose gradient ultracentrifugation methods and the gel filtration method had simlar performancec and correctly identified the immunocomplexes that caused the cTnI interference. CONCLUSIONS Our experience is that these methods are sufficient to safely confirm or exclude positive cTnI assay interference.
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Affiliation(s)
- Ola Hammarsten
- Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska Academy at University of Gothenburg, SE41345 Gothenburg, Sweden.
| | - Charlotte Becker
- Department of Clinical Chemistry and Pharmacology, Regional and University Laboratories, Region Skåne, Sweden
| | - Anna E Engberg
- Department of Clinical Chemistry and Pharmacology, Regional and University Laboratories, Region Skåne, Sweden
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8
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Paul HA, Chi Q, Gifford JL, Seiden-Long I. Not T too! False elevations in high-sensitivity cardiac troponin T (hs-TnT) following specimen transport. Clin Biochem 2022; 115:86-91. [PMID: 36027942 DOI: 10.1016/j.clinbiochem.2022.08.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 08/15/2022] [Accepted: 08/17/2022] [Indexed: 11/25/2022]
Abstract
Though false elevations attributed to preanalytical specimen handling have been widely reported for Troponin I (TnI), Troponin T (TnT) has appeared more robust to falsely elevated Tn. We describe reproducible false elevations in high sensitivity TnT (hs-TnT) in specimens after courier transport in plasma separator tubes (PST) off-site for testing. Hs-TnT was measured under 5 different conditions: 1) at collection location (N=24); 2) after transport upright in racks (N=66); 3) after transport with no control over tube agitation (N=69); 4) on transported aliquots (N=84); or 5) immediately after transport with no control over tube agitation (N=16), followed by keeping the specimen upright and re-measuring at 1hr, 2hr, 4hr, and 20-24hrs (N=6). To assess the degree of discrepancy, plasma from the original PST was aliquotted, re-centrifuged, potential debris removed, and hs-TnT re-measured. 43% of PST specimens collected offsite and transported with no control over tube agitation had clinically significant false elevations of hs-TnT which subsequently decreased following aliquotting and re-centrifugation (median decrease =9.9ng/L). Onsite testing or transported aliquots demonstrated no discrepancy. After being kept upright, discrepant specimens were not different from re-centrifuged aliquots by 4hrs (p=0.6141, repeated measures ANOVA with Dunn's multiple comparisons). Clinically significant false elevations of hs-TnT occurred in approximately 40% of separated PSTs that were transported in containers where specimens are transported with no control over tube agitation. This interference does not occur if plasma is aliquoted or if hs-TnT is tested at the collection site. In order to prevent these false elevations, and their potential patient impact on the diagnosis of acute myocardial infarction, specimens for hs-TnT measurement should be aliquoted at the collection location prior to transport.
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Affiliation(s)
- Heather A Paul
- Alberta Precision Laboratories and Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Qingli Chi
- Alberta Precision Laboratories, Calgary, Alberta, Canada
| | - Jessica L Gifford
- Alberta Precision Laboratories and Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Isolde Seiden-Long
- Alberta Precision Laboratories and Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada; Correspoooonding author at: Foothills Medical Centre, McCaig Tower, Rm 7507, 7(th) Floor, 3134 Hospital Drive NW, Canada.
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Lam L, Tse R, Gladding P, Kyle C. Effect of Macrotroponin in a Cohort of Community Patients with Elevated Cardiac Troponin. Clin Chem 2022; 68:1261-1271. [PMID: 35929566 DOI: 10.1093/clinchem/hvac118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 06/09/2022] [Indexed: 11/13/2022]
Abstract
BACKGROUND Macrotroponin is an important cause of discrepancy between current high-sensitivity cardiac troponin (hs-cTn) assays, however, its clinical significance is unclear. This study examined the effects of macrotroponin and repeat testing by different hs-cTnI assays in a cohort of community patients with elevated hs-cTnI. METHODS The first residual serum specimen from each patient in the community admitted to hospital with elevated hs-cTnI (Siemens hs-cTnI Centaur) was retested after immunoglobulin depletion and by 5 other hs-cTn assays. Low recovery of cTnI (<40%) following immunoglobulin depletion was considered as macrotroponin. A retrospective chart review was performed for these participants. Investigator-adjudicated diagnosis served as the reference standard. RESULTS In our cohort of community patients with elevated troponin (n = 188), participants with macrotroponin (n = 99) often had a multifactorial or indeterminate myocardial injury (56% vs 25%) and were less likely to have acute coronary syndrome (9% vs 28%). On repeat testing of cTn on other platforms, better diagnostic performance (c-statistics) for ischemic and non-ischemic cardiac causes was observed on the Beckman Access hs-cTnI (0.74; 95% confidence interval [CI] 0.67-0.81) or the Abbott hs-cTnI Architect (0.75; CI 0.68-0.82) compared to the Siemens hs-cTnI Vista (0.62; CI 0.54-0.70; P < 0.05). This could be attributed to differences in assay reactivity for macrotroponin. Interestingly, better diagnostic performance was observed in patients without macrotroponin. Although a small number of deaths occurred (n = 16), participants with macrotroponin had better overall survival. CONCLUSIONS In the low-risk setting, the presence of macrotroponin was clinically associated with multifactorial or indeterminate causes of troponin elevation.
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Affiliation(s)
- Leo Lam
- Chemical Pathology, LabPlus, Auckland City Hospital, Auckland, New Zealand.,Biochemistry, Middlemore Hospital Laboratories, Auckland, New Zealand
| | - Rexson Tse
- Forensic Pathology, LabPlus, Auckland City Hospital, Auckland, New Zealand
| | | | - Campbell Kyle
- Chemical Pathology, LabPlus, Auckland City Hospital, Auckland, New Zealand.,Biochemistry, Labtests, Auckland, New Zealand
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10
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Storage conditions, sample integrity, interferences, and a decision tool for investigating unusual high-sensitivity cardiac troponin results. Clin Biochem 2022; 115:67-76. [PMID: 35772501 DOI: 10.1016/j.clinbiochem.2022.06.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 05/31/2022] [Accepted: 06/22/2022] [Indexed: 11/24/2022]
Abstract
The current definition of high-sensitivity cardiac troponin (hs-cTn) assays is laboratory-based and their analytical attributes and characteristics have drawn significant attention in the literature at least partly due to the lower concentration cut-offs and changes in concentrations (i.e., deltas) employed in different algorithms and pathways to manage patient care. We propose that pre-analytical conditions such as sample type, storage conditions, and other interferences may also have a significant impact on hs-cTn concentrations and clinical management. The purpose of this literature review is to provide a summary of important pre-analytical and interference studies affecting hs-cTn concentrations. A breakdown of the literature for the major diagnostic companies providing core laboratory instrumentation (i.e., Abbott, Beckman, Ortho, Roche, and Siemens) is also provided. Finally, three cases are highlighted where knowledge of pre-analytical factors aids the hs-cTn clinically discordant investigations. This review highlights the importance of pre-analytical variables, especially storage condition, sample handling, and blood tubes used (i.e., sample type) when interpreting hs-cTn assays. Additional studies are needed to further elaborate on pre-analytical variables (i.e., centrifugation, sample type, stability) and interferences for all hs-cTn assays in clinical use, as knowledge of these variables may aid in hs-cTn clinically discordant investigations.
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11
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Lam L, Hammarsten O, Kyle C. Which method to detect macrotroponin? Clin Chem Lab Med 2022; 60:68-70. [PMID: 35007413 DOI: 10.1515/cclm-2021-1330] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Accepted: 12/29/2021] [Indexed: 11/15/2022]
Affiliation(s)
- Leo Lam
- Department of Chemical Pathology, LabPLUS, Auckland City Hospital, Auckland, New Zealand.,Biochemistry Department, Middlemore Hospital Laboratories, Middlemore Hospital, Auckland, New Zealand
| | - Ola Hammarsten
- Department of Laboratory Medicine Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden.,Department of Clinical Chemistry, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Campbell Kyle
- Department of Chemical Pathology, LabPLUS, Auckland City Hospital, Auckland, New Zealand.,Department of Biochemistry, LabTests, Auckland, New Zealand
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12
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Kavsak PA. Measurement in different sample types may aid in detecting interferences and macrocomplexes affecting cardiac troponin measurements. Clin Chem Lab Med 2022; 60:66-67. [PMID: 34989215 DOI: 10.1515/cclm-2021-1251] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 12/29/2021] [Indexed: 02/07/2023]
Affiliation(s)
- Peter A Kavsak
- McMaster University, Hamilton, ON, Canada.,Hamilton Health Sciences, Hamilton, ON, Canada
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