Absence of antibody to cyclic citrullinated peptide in sera of non-arthritic patients with chronic hepatitis B virus infection

The objective of this study was to investigate if antibody to cyclic citrullinated peptide (anti-CCP) is detected in sera of patients with chronic hepatitis B virus (HBV) infection. Serum anti-CCP and IgA, IgG, and IgM rheumatoid factor (RF) isotypes were measured by enzyme-linked immunosorbent assay on 176 non-arthritic patients with HBV infection. IgA RF, IgG RF, and IgM RF were detectable in 29.5, 21, and 18.8% of the tested sera, respectively, with a total seropositivity rate of 42.7%. Marginally elevated anti-CCP was detected in one patient (0.6%). By regression analysis, there was no statistically significant association between the serum levels of anti-CCP and serum IgA, IgG, or IgM RF (R²=0.033, with respective p values of 0.224, 0.297, and 0.334). In conclusion, anti-CCP was rarely detected in non-arthritic patients with HBV infection in contrast to RF. Thus, testing for anti-CCP may be a useful tool for the diagnosis of rheumatoid arthritis in this population.