The aim of this study was to investigate the influence of the infection with H. pylori on the local inflammatory response measured by the IL-1β, IL-6, IL-10, TNF, TGF-β and IL-17A mRNA expression in patients with bleeding duodenal ulcer, as well as to determine serum concentrations of IL-1β, IL-6, IL-10, TNF, TGF-β and IL-17A in those patients. The gene discussed is IL17A; the disease is duodenal ulcer.