Jeffrey Hedley1, Venu Menon1, Leslie Cho1, Adam J McShane2. 1. Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH 44195, USA. 2. Department of Laboratory Medicine, Cleveland Clinic, Cleveland, OH 44195, USA. Electronic address: mcshana@ccf.org.
Abstract
BACKGROUND: The fifth generation (high-sensitivity) troponin T assay offers increased precision and analytical sensitivity to the predecessor method. The assay has proven utility in risk stratification and patient management. Upon clinical suspicion and discordant 4th generation troponin T and troponin I results, we investigated a sample for suspected interfering substances to the 5th generation troponin T assay. METHODS: The analysis included a serial dilution, treatment with polyethylene glycol, commercial antibody blocking reagents, and size exclusion chromatography. RESULTS: The sample diluted linearly (R2 = 0.9957); however, experienced a dramatic reduction in concentration after both the polyethylene glycol and blocking agent treatment. Finally, size exclusion chromatography demonstrated assay reactivity around 970 kDa range. CONCLUSIONS: These experiments elucidate a heterophilic antibody interference to the assay, and demonstrate potential measures to discern the interference.
BACKGROUND: The fifth generation (high-sensitivity) troponin T assay offers increased precision and analytical sensitivity to the predecessor method. The assay has proven utility in risk stratification and patient management. Upon clinical suspicion and discordant 4th generation troponin T and troponin I results, we investigated a sample for suspected interfering substances to the 5th generation troponin T assay. METHODS: The analysis included a serial dilution, treatment with polyethylene glycol, commercial antibody blocking reagents, and size exclusion chromatography. RESULTS: The sample diluted linearly (R2 = 0.9957); however, experienced a dramatic reduction in concentration after both the polyethylene glycol and blocking agent treatment. Finally, size exclusion chromatography demonstrated assay reactivity around 970 kDa range. CONCLUSIONS: These experiments elucidate a heterophilic antibody interference to the assay, and demonstrate potential measures to discern the interference.