B-113 Diagnostic Value of Autoantibodies against D-3-phosphoglycerate Dehydrogenase (PGDH) among Patients with Liver Diseases

Abstract

Abstract Background We determined serum autoantibodies against D-3-phosphoglycerate dehydrogenase (anti-PGDH) in patients with liver diseases using a well-validated line immunoblot assay, and analysed their diagnostic significance. Methods The studied panel comprised serum samples from 383 patients with the following liver diseases: 87 autoimmune hepatitis (AIH), 88 primary biliary cholangitis (PBC), 76 chronic hepatitis B, 79 hepatitis C, 53 drug-induced liver injury as well as sera from 69 patients with autoimmune diseases (systemic lupus erythematosus or rheumatoid arthritis) and 30 healthy blood donors. The line immunoblot EUROLINE Autoimmune Liver Diseases 14 Ag (EUROIMMUN) was used to test for anti-PGDH. The intensities of the bands were automatically evaluated using the EUROLineScan software (EUROIMMUN). Indirect immunofluorescence was used to detect other autoantibodies, including anti-nuclear autoantibodies (ANA) and anti-smooth muscle antibodies (ASMA). Results The prevalence of anti-PGDH was 18.3% across all patients with liver diseases (36.8% in AIH; 10.2% in PBC), 1.5% in patients with autoimmune diseases, and 3.3% in blood donors. ANA but not ASMA were detectable in all anti-PGDH positive patients with liver diseases. Patients with anti-PGDH displayed no significant differences in age, liver function, IgG serum level and ANA patterns compared to those without anti-PGDH. Anti-PGDH positivity was observed at various stages of liver disease, including acute and chronic liver injury, liver cirrhosis, and liver cancer. Conclusion The anti-PGDH prevalence in AIH patients was highest among patients with liver or autoimmune diseases. Presence of anti-PGDH seems to be a specific marker for AIH and may support the diagnosis of AIH.