High-resolution magnification endoscopy can reliably identify normal gastric mucosa, Helicobacter pylori-associated gastritis, and gastric atrophy

Background and study aims: The aims of the study were to describe the magnified endoscopic findings in the gastric body, correlate these with histology, and evaluate their reproducibility in the assessment of the magnified endoscopic patterns seen. Patients and methods: A total of 95 consecutive dyspeptic patients underwent upper gastrointestinal endoscopy with a magnifying endoscope. The endoscopists classified the magnified endoscopic patterns and correlated them with the histological findings. In the second part of the study, 200 images were shown to five endoscopists in order to examine inter- and intraobserver variability in image assessment. Results: The magnified endoscopic findings in the gastric body were categorized into four types: type 1, honeycomb-type subepithelial capillary network (SECN) with regular arrangement of collecting venules and regular, round pits; type 2, honeycomb-type SECN with regular, round pits, but loss of collecting venules; type 3, loss of normal SECN and collecting venules, with enlarged white pits surrounded by erythema; and type 4, loss of normal SECN and round pits, with irregular arrangement of collecting venules. The sensitivity, specificity, and Positive and negative predictive values of the type 1 pattern for predicting normal gastric mucosa were 92.7% (95% confidence interval [Cl] 93.2% - 97.3%), 100% (95%Cl 83.9% - 100%), 100% (95%Cl 92.9% - 100%), and 83.8% (95%Cl 65.5% - 93.9%). The sensitivity, specificity, and positive and negative predictive values of types 2 and 3 patterns for predicting a Helicobacter pylori-infected stomach were 100% (95%Cl 83.9% - 100%), 92.7% (95%Cl 93.2% - 97.3%), 83.8% (95%Cl 65.5% - 93.9%), and 100% (95%Cl 92.9% - 100%). The sensitivity, specificity, and positive and negative predictive values of a type 4 pattern for predicting gastric atrophy were 90% (95%Cl 66.8% - 98.2%), 96% (95%Cl 87.9% - 98.9%), 85.7% (95%Cl 62.6% - 96.2%), and 97.3% (95%Cl 89.6%-99.5%. The kappa values for inter- and intraobserver agreement in predicting normal gastric mucosa, H. pylori gastritis, and gastric atrophy were 0.864 and 0.913 respectively. Conclusion: High-resolution magnification endoscopy can reliably identify the normal gastric mucosa, H. pylori associated gastritis, and gastric atrophy in a Western population.