Should increased levels of urinary 8-hydroxydeoxyguanosine in chronic gastritis imply intestinal metaplasia or gastric atrophy?

OBJECTIVES: Helicobacter pylori (H pylori) infection induces chronic inflammation that can progress to gastric atrophy, intestinal metaplasia, and gastric adenocarcinoma. We have examined oxidative damage caused by Helicobacter pylori, metaplasia, and atrophy of gastric mucosal cells in patients with chronic gastritis by measuring their urinary 8-hydroxydeoxyguanosine (8-OHdG) levels. METHODS: We recruited 77 outpatients with chronic gastritis, confirmed by endoscopic examination. H pylori status was evaluated by histology (modified Giemsa staining), the H pylori stool antigen test (n=20), and the 13C urea breath test (n=27), as described in the Maastricht consensus report. RESULTS: The mean amount of 8-OHdG (microg/g creatinine) in 77 subjects was 18.07 +/- 13.49 x 10(-3) microg/g creatinine. The levels of urinary 8-OHdG in the H pylori-positive gastritis patients were also significantly higher than those in the H pylori-negative gastritis patients (P=0.003, respectively, 20.42 +/- 13.33 x 10(-3) microg/g creatinine, 13.16 +/- 12.71 x 10(-3) microg/g creatinine). The level of urinary 8-OHdG was markedly higher in patients with gastric atrophy and intestinal metaplasia than in those without (P=0.000, P=0.002, respectively). There were significant correlations between levels of urinary 8-OHdG and both the atrophy score (r=0.441, P=0.000) and the intestinal metaplasia score (r=0.436, P=0.000). CONCLUSIONS: Urinary 8-OHdG levels could be investigated in every patient with chronic gastritis, since it is a simple and completely noninvasive procedure. In patients with high levels of urinary 8-OHdG, endoscopic procedures or even pathological investigation may then be carried out, with the consideration that there is a high risk of intestinal metaplasia or atrophy.