RT Journal Article SR Electronic T1 Anti-Cyclic Citrullinated Peptide Antibodies Distinguish Hepatitis B Virus (HBV)-associated Arthropathy from Concomitant Rheumatoid Arthritis in Patients with Chronic HBV Infection JF The Journal of Rheumatology JO J Rheumatol FD The Journal of Rheumatology SP jrheum.080653 DO 10.3899/jrheum.080653 A1 Mi-Kyoung Lim A1 Dong-Hyuk Sheen A1 Yun Jung Lee A1 You Ri Mun A1 Mira Park A1 Seung-Cheol Shim YR 2009 UL http://www.jrheum.org/content/early/2009/03/13/jrheum.080653.abstract AB Objective To determine whether anti-cyclic citrullinated peptide (anti-CCP) antibodies, which are a highly specific test for rheumatoid arthritis (RA), could differentiate between hepatitis B virus (HBV)-associated arthropathy and concomitant RA in Korean patients with chronic HBV infection. Methods We investigated 240 patients with HBV infection. Anti-CCP antibodies were measured by ELISA and rheumatoid factor (RF) by the latex fixation test. Patient records were reviewed, and a standard form was used to record all demographic, clinical, and laboratory characteristics. Patients were divided into 4 groups according to joint symptoms: asymptomatic, arthralgia, oligoarthritis, and RA. We categorized liver disease into 3 groups: carrier, chronic hepatitis, and cirrhosis. Results Anti-CCP antibodies and RF were detected in 11 and 28 of 240 patients, respectively. Anti-CCP antibodies were detected in 9 of 10 RA (90%) and 2 of 230 non-RA patients (0.86%). The positive rate for RF was 90% in RA and 8.3% in non-RA. Eight of 10 RA patients were positive for both RF and anti-CCP antibodies. RF was detected in 11 patients without joint symptoms, 4 with arthralgia, and 4 with oligoarthritis, whereas anti-CCP antibodies were found in 1 patient without joint symptoms and 1 with oligoarthritis. Specificity of anti-CCP antibody for RA was 99.1%, whereas RF showed 91.7% specificity (p < 0.0002). We compared the titers and positive detection rates of anti-CCP antibodies and RF among liver disease subgroups. There was no significant between–subgroup difference. Conclusion Measurement of anti-CCP antibodies is better than RF detection to discriminate HBV-associated arthropathy from concomitant RA in patients with chronic HBV infection.