The association between hepatitis B virus infection and disease activity, synovitis, or joint destruction in rheumatoid arthritis

The prevalence of chronic hepatitis B virus (HBV) infection in China is high. Four percent of patients with HBV infection can present with polyarthritis and positive rheumatic factor similar to rheumatoid arthritis (RA). Here, we investigated the association between HBV infection and serological, radiological, or histological disease status in RA. According to HBV infection status, 223 consecutive hospitalized Chinese patients with RA were divided into the groups of chronic HBV infection, past HBV infection, and no HBV infection. Clinical data and hand radiographs were collected. Synovium was obtained by closed-needle biopsy, and serial tissue sections were stained immunohistochemically for HBV surface antigen (HBsAg) and cluster of differentiation (CD) markers. (1) The prevalence of HBsAg positivity and chronic hepatitis B in RA was consistent with the age-matched general Chinese population (11.2 vs. 8.7 %, 1.7 vs. 1.0 %, respectively, P > 0.05). (2) Clinical parameters, disease activity score in 28 joints, or Sharp scores showed no significant difference among the three groups in 206 RA or 140 treatment-naïve patients, both with active disease (all P > 0.05). (3) Synovial immunohistochemical staining showed negative HBsAg in ten RA patients with HBV carrier status and ten RA patients with past HBV infection. Except for higher subintimal CD3+ cell density in the past HBV infection group, Krenn’s synovitis score, mean densities of subintima positive-staining cells (CD20, CD38, CD79a, and CD68), and CD34+ microvessel counts showed no significant difference among RA patients with HBV carrier status, past HBV infection, or no HBV infection (all P > 0.05). Chronic HBV infection may have no significant effect on disease activity, synovitis, or joint destruction in RA.