Standard vs magnifying narrow-band imaging endoscopy for diagnosis of Helicobacter pylori infection and gastric precancerous conditions

BACKGROUND Advances in endoscopic imaging enable the identification of patients at high risk of gastric cancer.However,there are no comparative data on the utility of standard and magnifying narrow-band imaging(M-NBI)endoscopy for diagnosing Helicobacter pylori(H.pylori)infection,gastric atrophy,and intestinal metaplasia.AIM To compare the diagnostic performance of standard and M-NBI endoscopy for H.pylori gastritis and precancerous conditions.METHODS In 254 patients,standard endoscopy findings were classified into mosaic-like appearance(type A),diffuse homogenous redness(type B),and irregular redness with groove(type C).Gastric mucosal patterns visualized by M-NBI were classified as regular round pits with polygonal sulci(type Z-1),more dilated and linear pits without sulci(type Z-2),and loss of gastric pits with coiled vessels(type Z-3).RESULTS The diagnostic accuracy of standard and M-NBI endoscopy for H.pylori gastritis was 93.3%and 96.1%,respectively.Regarding gastric precancerous conditions,the accuracy of standard and M-NBI endoscopy was 72.0%vs 72.6%for moderate to severe atrophy,and 61.7%vs.61.1%for intestinal metaplasia in the corpus,respectively.Compared to type A and Z-1,types B+C and Z-2+Z-3 were significantly associated with moderate to severe atrophy[odds ratio(OR)=5.56 and 8.67]and serum pepsinogen I/II ratio of≤3(OR=4.48 and 5.69).CONCLUSION Close observation of the gastric mucosa by standard and M-NBI endoscopy is useful for the diagnosis of H.pylori gastritis and precancerous conditions.