Non-organ-specific autoantibodies in Indian patients with chronic liver disease

Abstract

Background: Autoantibody testing is used to diagnose autoimmune hepatitis (AIH), a cause of chronic liver disease (CLD). However, various autoantibodies are often detectable in patients with CLD due to other causes too. Since data on autoantibody prevalence in Indian patients with CLD are limited, we decided to undertake the current study. Methods: Patients with CLD with a known cause other than AIH and a separate group of patients with CLD in whom no cause could be identified were studied. Indirect immunofluorescence assays were used to detect anti-nuclear antibodies (ANA), anti-smooth muscle antibodies (ASMA) and anti-liver-kidney microsomal antibodies (anti-LKM). Serum dilutions tested were 1:80 for ANA and 1:40 for other autoantibodies. Results: Of the 175 patients with CLD of a known cause, 69 (39 %) had one or more autoantibodies, including ANA in 35 (20 %) patients and ASMA in 44 (25 %) patients. None had anti-LKM. The prevalence rates of any autoantibody, ANA and ASMA were similar in patients with CLD due to alcohol (34 %, 20 %, and 24 %, respectively), HCV infection (43 %, 20 %, and 26 %) and HBV infection (40 %, 18 %, and 25 %). The most common ANA pattern observed was speckled (29/35 patients), followed by nucleolar (5/35) and homogeneous (1/35). The ASMA titers did not exceed 1:80. The antibody prevalence rates were similar in patients with liver cirrhosis and chronic hepatitis, and in those with different disease severity. Serum IgG levels were similar in patients with and without detectable autoantibodies. Patients with no known cause of CLD (n = 50) had similar prevalence rates of autoantibodies, ANA or ASMA. Conclusion: Autoantibodies were detected in a large proportion of patients with CLD, both cryptogenic and with known cause. Detection of autoantibodies in CLD does not necessarily indicate a diagnosis of AIH, and presence of homogenous pattern of ANA may be more relevant. Indiscriminate testing for autoantibodies in patients with CLD, especially those with a known cause, may not be warranted.