Autoantibodies against cyclic citrullinated peptide (anti-CCP) are sensitive and highly specific markers for rheumatoid arthritis (RA). We evaluated the analytical and diagnostic accuracy of chemiluminescence enzyme immunoassay (CLEIA) for anti-CCP antibodies, and compared it with that of ELISA.
Ninety-nine RA patients who were diagnosed according to the American College of Rheumatology criteria, 16 patients with osteoarthritis, and 94 healthy subjects were included. Sera were used to assess the precision, functional sensitivity, and linearity of anti-CCP antibody determination by CLEIA and the correlation of anti-CCP antibody values between CLEIA and ELISA.
For anti-CCP antibodies by CLEIA, the total CV was 4.0 and 5.3% at 21.17 and 90 U/ml, respectively, and the lower limit of detection was 0.1 U/ml. The correlation of CLEIA (x) with ELISA (y) for anti-CCP was: y=1.08x+4.171, r=0.9178 (p<0.0001). No difference was observed in the sensitivity and specificity between CLEIA and ELISA.
The automated CLEIA processing system for determining anti-CCP antibodies showed a good analytical performance, and suggested that the CLEIA system has a potential to provide clinically useful data within a short time.