Highly Sensitive Cardiac Troponin I Assay Leads to Lowered Specificity

I read with great interest the article of Kavsak et al. (1) on the utility of a next-generation high-sensitivity Beckman Coulter cardiac troponin I (cTnI) assay with a 20% CV at 2.95 ng/L. This approach demonstrated a higher diagnostic sensitivity (81% vs 62%) for myocardial injury with a changing pattern of cTnI values, compared with the AccuTnI® assay cleared by the US Food and Drug Administration (1). This high-sensitivity assay had an unexpectedly high prevalence (3%) for interfering heterophilic antibodies compared with the 0.05% prevalence …