Clinical evaluation of a novel chemiluminescent immunoassay for the detection of anti-citrullinated peptide antibodies

• QUANTA Flash CCP3 is a fast (30 min) and reliable assay to measure ACPA.
• All ACPA assays show good correlation.
• Higher ACPA titers have higher predictive value.

BackgroundWe evaluated the analytical and clinical performances of a novel, automated chemiluminescent immunoassay in comparison with several anti-citrullinated protein antibody (ACPA) assays (2nd and 3rd generations) based on various platforms and technologies.MethodsSamples from rheumatoid arthritis (RA) patients (n = 141) and controls (n = 153) were collected based on an ordered ACPA test. All samples were tested with QUANTA Flash® CCP3, QUANTA Lite® CCP3, QUANTA Lite® CCP3.1, CCPlus and EliA® CCP assays. Rheumatoid factor (RF) was determined using Quantex RF(II). An additional cohort consisting of RA patients from three different sources (116, 79 and 50 samples), 61 juvenile idiopathic arthritis (JIA) patients and 233 controls were used in an extended evaluation on QUANTA Flash® CCP3 only. Precision and linearity of the QUANTA Flash® CCP3 were assessed according to CLSI guidelines.ResultsAll ACPA assays showed good qualitative and quantitative agreements. The Quanta Flash CCP3 assay showed good analytical and clinical performance. Based on the extended cohort, the sensitivity, specificity and likelihood ratios of the novel Quanta Flash® CCP3 were defined as 70.2%, 97.4% and 27.3/0.31, respectively.ConclusionGood agreements between different ACPA assays based on diverse platforms were found. Quanta Flash CCP3 is a reliable test for the fully automated and rapid detection of ACPA.