Assessment of Access hsTnI 99th percentiles upper reference limits following IFCC recommendations

• Published in: Clinica chimica acta Vol. 492; pp. 26 - 28
• Main Authors: Di Pietro, Martina, Dipalo, Mariella, Rocchi, Marco Bruno Luigi, Musa, Roberta, Avanzini, Paola, Gnocchi, Cecilia, Anelli, Maria Chiara, Aloe, Rosalia
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.05.2019
• Subjects: 99th percentile; High-sensitivity Troponin I; IFCC recommendations; Limit of Blank; Limit of Detection; Limit of Quantitation; Limit of Blank; High-sensitivity Troponin I; 99th percentile; Limit of Detection; IFCC recommendations; Limit of Quantitation
• ISSN: 0009-8981; 1873-3492
• DOI: 10.1016/j.cca.2019.01.028

The detection of an increase and/or decrease of cardiac troponin (cTnI) values, with at least one value above the 99th percentile of the upper reference limit (URL) have a central role in acute myocardial infarction (AMI) diagnosis. The employment of sex specific 99th percentile URLs and High-sensitivity (Hs) assays are recommended. We assessed sex specific 99th percentile URL for Access Hs-cTnI and AccuTnI3+ (Beckman Coulter) using European donor reference population following recent International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) recommendations. 300 males and 300 females plasma samples were collected. Both chemiluminescent immunoenzymatic assays were performed on UniCel DxI 800 platform (Beckman Coulter). For Access hsTnI, the observed sex-specific 99th percentile URLs were 5.5 (90% CI: 4.4–7.6) for females and 13.9 ng/L (90% CI: 7.4–17.4) for males. For AccuTnI+3 we could not establish them because the assay couldn't report detectable values of troponin for most of the analyzed samples. The sex-specific 99th percentile URLs established for Access hsTnI assay were significantly lower than those declared by the manufacturer caused by the different choice of population selection, age groups and sample types: for those reasons, we maintain the 99th URLs provided by manufacturer. •Sex specific 99th upper reference limits for troponins are recommended by guidelines.•Study on 300 males and 300 females from European donor reference population.•We gave sex specific cut-offs for high-sensitivity troponin; not for contemporary one.•Our sex-specific reference limits were lower than those provided by the manufacturers.•We maintain the 99th upper reference limits declared by the manufacturer.