Evaluation of Anti-Nuclear and Liver-Specific Autoantibodies in Patients with Chronic HBV and HCV Infection

Background: Serum non–organ-specific autoantibodies (NOSA), including antinuclear antibodies (ANA) and anti-smooth muscle antibodies (ASMA), as well as liver-specific autoantibodies such as anti-mitochondrial antibodies (AMA) and liver–kidney microsomal antibodies (LKM), may be detected in patients with chronic viral hepatitis. However, their clinical relevance in hepatitis B virus (HBV) and hepatitis C virus (HCV) infections remains unclear. This study aimed to evaluate the frequency and patterns of autoantibodies in patients with chronic HBV and HCV infection. Methods A total of 373 patients with chronic viral hepatitis were included: 313 HBsAg-positive patients (HBV group) and 60 anti-HCV–positive patients (HCV group). Serological markers were analyzed using chemiluminescent immunoassays, and viral loads were quantified by real-time PCR. Autoantibodies (ANA, ASMA, AMA, LKM) were assessed by indirect immunofluorescence, and available extractable nuclear antigen immunoblot results were evaluated. Results ANA positivity was detected in 15.7% of HBV patients and 21.7% of HCV patients. ASMA positivity was similar between groups, while AMA was detected only in a small proportion of HBV patients; LKM antibodies were absent in both groups. In HBV patients, the predominant ANA patterns were speckled, nucleolar, and homogeneous. HBV DNA levels tended to be higher in ANA-positive patients, although the difference was not statistically significant. Conclusions Autoantibody positivity—particularly ANA—in chronic HBV and HCV infection appears to reflect nonspecific immune activation rather than autoimmune liver disease and should be interpreted cautiously to avoid misdiagnosis.