Performance characteristics of three random access cyclic citrullinated peptide antibody assays

BackgroundCyclic citrullinated peptide antibodies (CCP Ab) are useful biomarkers for the early detection and diagnosis of rheumatoid arthritis (RA).MethodsWe evaluated the performance of 3 random access 2nd generation CCP Ab assays, the Abbott AxSYM and Architect analyzers and the Roche Modular Analytics E170 analyzer, for limit of detection (LOD), imprecision, results for samples from healthy subjects, analytic concordance, and interferences. Method comparison testing was performed using the AxSYM analyzer as the comparison method and a 3rd generation INOVA Quanta Lite ELISA assay was included.ResultsLOD determinations met the manufacturers' claims. Total CVs ranged from 1.6% to 8.2%. Results from healthy subjects were generally much lower than the manufacturers' decision cutoffs. Comparison to the AxSYM assay resulted in overall concordance ranging from 82.1% to 98.3%. These assays were resistant to interference from hemolysis, icterus, lipemia and rheumatoid factor.ConclusionAll 3 random access CCP Ab assays performed according to the manufacturers' claims and have the potential to improve workflow in clinical laboratories.