Simultaneous detection of Helicobacter pylori infection comparing between white light and image-enhanced endoscopy.

Background: Helicobacter pylori (H. pylori) is associated with gastric cancer. Early and accurate diagnosis of H. pylori infection can reduce risk of gastric cancer. Conventional white light imaging (WLI) and image-enhanced endoscopic (IEE) techniques such as narrow-band imaging (NBI), linked color imaging (LCI) and blue laser imaging (BLI) plays pivotal role in H. pylori diagnosis. This study aimed to determine diagnostic performance of real-time endoscopy between WLI and other IEE techniques for diagnosis of H. pylori infection.

Methods: This prospective study compared endoscopic images by gastroscopy using WLI and IEE techniques (LCI, Magnifying-BLI, and Magnifying-NBI) at Thammasat University Hospital, Thailand between January 2020, and July 2021. All participants underwent gastroscopy. Three biopsies at gastric antrum and two biopsies at body were obtained for H.pylori diagnosis. H. pylori infection was defined as a positive test of either one of the following tests: rapid urease test, histopathology, H. pylori culture.

Results: Of 167 dyspeptic patients undergoing gastroscopy, 100 were enrolled in this study. Overall H. pylori infection was 40%. Patients had the mean age of 59.1 years and 53% were males. Enlarged gastric folds and antral nodularity can predict H. pylori infection with 100% PPV, while fundic gland polyps and red streak provided 100% PPV for exclusion of H. pylori infection on WLI. Sensitivity, specificity, PPV, NPV and accuracy for diagnosis of H. pylori infection for WLI were 80%, 71.7%, 65.3%, 84.3% and 75% respectively, while those for LCI were 90%, 70%, 66.7%, 91.3% and 78% respectively. M-NBI and M-BLI endoscopy demonstrated elongated pits in H. pylori-positive patients. Sensitivity, specificity, PPV, NPV and accuracy for M-BLI were 95%, 80%, 76%, 96% and 86% respectively, whereas those for M-NBI were 92.5%, 86.7%, 82.2%, 94.6% and 89% respectively. Sensitivity of M-BLI was better than WLI, while sensitivities of LCI and M-NBI were also numerically higher than WLI without statistical difference (M-BLI 95%vs.WLI 80%, p = 0.03; M-NBI 92.5%vs.WLI 80%, p = 0.13; LCI 90%vs.WLI 80%, p = 0.22). Sensitivities of all IEE modes were not different from one another (LCI 90%vs.M-BLI 95%, p = 0.50; LCI 90%vs.M-NBI 92.5%, p = 1.00, M-BLI 95%vs.M-NBI 92.5%, p = 1.00).

Conclusions: M-BLI significantly improved sensitivity of real-time endoscopic diagnosis of H. pylori infection compared with WLI. Enlarged gastric folds and antral nodularity could be reliable predictors for H. pylori infection, while fundic gland polyps and red streak could be important endoscopic findings for H. pylori-negative mucosa.