Increased density of Helicobacter pylori on antral biopsy is associated with severity of acute and chronic inflammation and likelihood of duodenal ulceration.

An increased risk of ulcers and severity of inflammation with increased degree of Helicobacter pylori (HP) infection (biological gradient) would support the hypothesis that HP causes ulcers. A blinded pathologist evaluated antral biopsies obtained at endoscopy in 903 patients. The level of HP infection was assessed on Warthin Starry stain, and the severity of acute and chronic inflammation on hematoxylin and eosin graded from 0 to 3. The presence of duodenal ulcers was associated with increasing HP density (grade 0, 6%; grade 1, 16%; grade 2, 19%; and grade 3, 27%) (p less than 0.0001, Wilcoxon rank sum test). Only a weak association between HP and gastric ulcers was detected (p = 0.06, Wilcoxon rank sum test), and this association diminished after adjusting for other risk factors. An increased acute and chronic inflammatory response correlated with increasing HP concentration (p less than 0.0001, Cochran-Mantel-Haenszel correlation statistic. The presence of this biologic gradient supports the hypothesis that HP is pathogenic in duodenal ulcers and in acute and chronic gastritis.