[Parietal cell antibodies in primary biliary cirrhosis: pathogenetic or diagnostic significance?]

24 patients with primary biliary cirrhosis (21 female, 3 male; mean age 51 years) were examined for the occurrence of autoantibodies to gastric parietal cells (APA). APA-titers were correlated with several hematological, chemical and immunological parameters. The results of upper GI-endoscopy were available from 12 patients. APA were positive in 24/24 PBC patients. None of the endoscopies revealed evidence for type A gastritis. No pathological decrease in serum vitamin B12 was found (n = 21). Hemoglobin was either normal (n = 18) or the anemia was microcytic with low serum ferritin (n = 6). Erythrocyte MCV was < or = 97 fl in all patients. No positive correlation was found between APA and erythrocyte sedimentation rate (r = 0.13, n = 24) or the titer of antinuclear antibodies (r = -0.18, n = 24) by linear regression. Correlation coefficient between APA and total serum-Ig was 0.67 (n = 24), 0.74 between APA and serum IgM (n = 24) and 0.13 between total serum-Ig minus IgM (n = 24), indicating that APA found in PBC patients belong to the IgM-isotype. Correlation between APA and anti-M2 was 0.65 (n = 21) and between APA and antimitochondrial antibodies (AMA) 0.96 (n = 24), suggesting recognition of identical epitope(s) by APA and AMA in PBC patients. APA were consistently negative in a control group of 40 patients with various forms of chronic liver disease. We conclude that parietal cell antibodies (APA) in PBC patients seem to be of diagnostic rather than pathogenic importance. Sensitivity for PBC appears comparable to that of AMA.(ABSTRACT TRUNCATED AT 250 WORDS)