[Atrophic gastritis in Sjögren's syndrome].

In patients with Sjögren's syndrome (SJS), it has been found that chronic atrophic gastritis is often associated with low HCl secretion or achlorhydria. However, the role of autoimmune injuring mechanism in the pathogenesis of the atrophic gastritis in SJS is unclear. In recent studies, Helicobacter pylori (HP) infection is accepted as the major cause of chronic gastritis. In our studies, HP infection was present in the half of SJS patients with atrophic gastritis. We also determined HP specific IgG antibody levels by enzyme-linked immunosorbent assay (ELISA). In SJS patients with gastric inflammatory cell infiltration, the IgG levels were high. We determined gastric parietal cell antibody (PCA) levels by ELISA, using a recombinant fusion protein of the alpha subunit of gastric H+, K(+)-ATPase. Our observation suggests that atrophic gastritis in SJS is caused by HP infection associated with gastric mucosal injury due to PCA.