AIM:Because the presence or absence of H pylori infectionhas important implications for therapeutic decisions basedon histological assessment,the reproducibility of Sydneysystem is important.The study was designed to test thereproducibility of features of Helicobacter pylori gastritis,using the updated Sydney classification.METHODS:Gastric biopsies of 40 randomly selected casesof H pylori gastritis were scored semiquantitatively by threepathologists.Variables analysed induded chronic inflammation,inflammatory activity,atrophy,intestinal metaplasia,H pylori,surface epithelial damage.κ values below 0.5 representedpoor,those between 0.5 and 0.75 good and values over 0.75excellent interobserver agreement.RESULTS:The best interobserver agreement(κ=0.62)waspresent for intestinal metaplasia.The agreement was thepoorest for evaluating atrophy(κ=0.31).CONCLUSION:Although the results of this study were inaccordance with some previous studies,an excellentagreement could not be reached for any features of H pylorigastritis.This low degree of concordance is assumed to bedue to the personal evaluation differences in grading thefeatures,the lack of standardized diagnostic criteria,andthe ignorance to reach a consensus about the methods tobe used in grading the features of H pylori gastritis beforeinitiating the study. AIM: Because the presence or absence of H pylori infectionhas significant implications for therapeutic decisions basedon histological assessment, the reproducibility of Sydneysystem is important. The study was designed to test thereproducibility of features of Helicobacter pylori gastritis, using the updated Sydney classification. METHODS: Gastric biopsies of 40 randomly selected cases of H pylori gastritis were scored semiquantitatively by three pathologists. Variables were identified inducted chronic inflammation, inflammatory activity, atrophy, intestinal metaplasia, H pylori, surface epithelial damage. κ values ​​below 0.5 representedpoor, those between 0.5 and 0.75 good and values over 0.75 excellent interobserver agreement. RESULTS: The best interobserver agreement (κ = 0.62) waspresent for intestinal metaplasia.The agreement was thepoorest for evaluating atrophy (κ = 0.31) .CONCLUSION: Although the results of this study were inaccordance with some previous studies, an excellentagreement could not be reached for any features of H pylorigastritis. This low degree of concordance was assumed to bed to the personal evaluation differences in grading the features, the lack of standardized diagnostic criteria, and the ignorance to reach a consensus about the methods to be used in grading the features of H pylori gastritis beforeinitiating the study.