RELATIONSHIP BETWEEN INFECTIVE LOAD OF HELICOBACTER-PYLORI AND REACTIVE OXYGEN METABOLITE PRODUCTION IN ANTRAL MUCOSA

Helicobacter pylori infection has been associated with stimulation of gastric mucosal reactive oxygen metabolite production. To provide furt her evidence of a causal relationship we looked for a dose-response re lationship. We studied antral biopsy material from 110 patients. Quant itative H. pylori assessments were made using histologic and microbiol ogic methods. Reactive oxygen metabolite production was measured by lu minol-dependent chemiluminescence. The usefulness of timed urease test colour changes as a guide to infective load was assessed. There was a positive association between mucosal reactive oxygen metabolite produ ction and histologic (p = 0.002, n = 69) and microbiologic (Spearman's R = + 0.6, p = 0.05, n = 18) quantitative H. pylori assessments. H. p ylori infective load varied markedly over small areas (coefficient of repeatability of paired cultures (in colony-forming units/mg) = 1.9 x 10(6)). Urease test timing correlated with histologic (p = 0.01) and m icrobiologic (p = 0.03) H. pylori quantitation. Histologically assesse d mucosal damage was related to quantitative H. pylori assessment and to mucosal reactive oxygen metabolite production (p = 0.0001). These r esults support the hypothesis that H. pylori stimulates gastric mucosa l reactive oxygen metabolite production and that this phenomenon is of pathogenic importance.