Prevalence of gastric parietal cell antibodies and intrinsic factor antibodies in primary biliary cirrhosis

BackgroundWe investigated the prevalence of antibodies against gastric parietal cells (GPA), intrinsic factor antibodies (IFA) and the presence of pernicious anemia in a large cohort of primary biliary cirrhosis (PBC) patients as similar data is missing.Methods157 PBC patients and 357 controls (73 with autoimmune hepatitis (AIH), 35 primary sclerosing cholangitis (PSC), 45 HBV, 37 HCV, 36 alcoholic liver disease (ALD), 35 non-alcoholic fatty liver disease (NAFLD) and 96 healthy) were investigated for IgG-isotype-specific GPA and IFA by ELISAs and vitamin-B₁₂ levels by a microparticle enzyme immunoassay.ResultsThe detection of IgG-GPA was significantly higher in PBC (31.8%) compared to AIH (10.9%; p = 0.001), PSC (0%; p = 0.000), HCV (13.5%; p = 0.01), HBV (13.3%; p = 0.006), ALD (8.3%; p = 0.004), NAFLD (11.4%; p = 0.003) and healthy (10.4%; p = 0.001). IgG-IFA were detected in 12% of GPA-positive PBC patients and in none of the other liver diseases or in healthy (p = 0.001). This reactivity was significantly associated with lower vitamin-B₁₂ levels compared to those with an IFA-negative test (p = 0.025).ConclusionsA significant proportion of PBC patients had IgG-GPA and IFA compared to controls. IgG-IFA were detected only in GPA-positive PBC patients and associated with lower vitamin-B₁₂ levels compared to those with an IFA-negative test.