Changes in Helicobacter pylori Immunoglobulin G Levels and Gastric Mucosal Atrophy after Successful Eradication of Helicobacter pylori

ABSTRACT

BACKGROUND/AIMS: Limited information is available about the relationship between Helicobacter pylori (H. pylori) immunoglobulin (Ig) G and serum pepsinogen (pepsinogen [PG], a marker of gastric mucosal atrophy) concentrations after H. pylori eradication. MATERIALS AND METHODS: Eligible patients who underwent endoscopic submucosal dissection (ESD) for early gastric cancer from August 2007 to March 2013 in a tertiary-referral center, and whose serum H. pylori IgG and PG concentrations were measured at the time of performing ESD and one year post-ESD, were selected. Successful H. pylori eradication was achieved after ESD in all the patients. According to the decrease in serum H. pylori IgG concentration after bacterial eradication, the patients were categorized as group 1 (IgG concentration decreased by <50%), and group 2 (IgG concentration decreased by ≥50%). RESULTS: Of the 106 patients, 25 (23.6%) were classified into group 1 and 81 (76.4%) into group 2. One year after H. pylori eradication, the serum PG II concentration was significantly decreased in group 2 (12.46±8.18 vs. 8.28±6.11, P=0.024). Although the serum PG I/II ratio of group 2 was higher than that of group 1 (8.32±4.52 ng/mL vs. 6.39±4.04 ng/mL), the difference was not significant (P=0.058). One year after successful eradication, elevated serum PG I/II ratio was observed in 21 patients (84%) in group 1 and in 77 patients (95.1%) in group 2 (P=0.087). The mean serum PG I/II ratio was also elevated in both groups. Serum PG II concentration was significantly decreased in group 2. CONCLUSIONS: A notable decrease in the concentration of H. pylori IgG antibody after bacterial eradication might reflect gastric mucosal atrophy. However, our study showed no statistically significant difference.