Accuracy of endoscopic diagnosis of Helicobacter pylori infection according to level of endoscopic experience and the effect of training

Abstract

Background: Accurate prediction of Helicobacter pylori infection status on endoscopic images can contribute to early detection of gastric cancer, especially in Asia. We identified the diagnostic yield of endoscopy for H. pylori infection at various endoscopist career levels and the effect of two years of training on diagnostic yield.

Methods: A total of 77 consecutive patients who underwent endoscopy were analyzed. H. pylori infection status was determined by histology, serology, and the urea breast test and categorized as H. pylori-uninfected, -infected, or -eradicated. Distinctive endoscopic findings were judged by six physicians at different career levels: beginner (<500 endoscopies), intermediate (1500-5000), and advanced (>5000). Diagnostic yield and inter- and intra-observer agreement on H. pylori infection status were evaluated. Values were compared between the two beginners after two years of training. The kappa (K) statistic was used to calculate agreement.

Results: For all physicians, the diagnostic yield was 88.9% for H. pylori-uninfected, 62.1% for H. pylori-infected, and 55.8% for H. pylori-eradicated. Intra-observer agreement for H. pylori infection status was good (K > 0.6) for all physicians, while inter-observer agreement was lower (K = 0.46) for beginners than for intermediate and advanced (K > 0.6). For all physicians, good inter-observer agreement in endoscopic findings was seen for atrophic change (K = 0.69), regular arrangement of collecting venules (K = 0.63), and hemorrhage (K = 0.62). For beginners, the diagnostic yield of H. pylori-infected/eradicated status and inter-observer agreement of endoscopic findings were improved after two years of training.

Conclusions: The diagnostic yield of endoscopic diagnosis was high for H. pylori-uninfected cases, but was low for H. pylori-eradicated cases. In beginners, daily training on endoscopic findings improved the low diagnostic yield.

Figure 1

Different sites of the stomach showing H. pylori infection status. a. Cardia with hemorrhage. b. Lesser and greater curvature of lower body with atrophy, and spotty erythema. c. Angulus with regular arrangement of collecting venules. d. Greater curvature of the upper body with exudates, edema, and rugal hyperplasia. e. Lesser curvature of lower body with xanthoma. f. Antrum with motteled patchy erythema.

Figure 2

Comparison of diagnostic yield of H. pylori infection status in two beginner endoscopists before and after training. Diagnostic yield of Beginner 1 (A) and Beginner 2 (B). ^†P-values are statistically significant at <0.05. Analysis performed using Mcnemer’s test. Error bar represents the 95% CI of diagnostic yield. Abbreviations: HP, H. pylori; PPV, positive predictive value.