USEFULNESS OF NEAR-FOCUS MAGNIFICATION WITH NARROW-BAND IMAGING IN THE PREDICTION OF HELICOBACTER PYLORI INFECTION: A PROSPECTIVE TRIAL

Aims It has been shown that conventional white-light (WL) endoscopic findings often labeled as Helicobacter pylori (H. pylori)-associated gastritis are poorly informative. Therefore, we investigated the performance of near focus (NF)-NBI, a novel simplified and modest magnifying endoscopy, for predicting H. pylori infection compared with WL endoscopy.

Methods A total of 115 consecutive patients who underwent esophagogastroduodenoscopy were prospectively enrolled. In NF-NBI endoscopy, we classified gastric mucosal patterns into four categories according to pit patterns, subepithelial capillary network (SECN), collecting venules (CV), and vascular density. Only type 1 pattern (small and round pits with regular SECN and visible CVs) was diagnosed as non-H. pylori infection, others as H. pylori infection. H. pylori status based on WL and NF-NBI images was judged by three endoscopist.

Results Interobserver agreement was moderate in both groups. The sensitivity, specificity, positive predictive values, and negative predictive value were 57.7%, 92.1%, 53.0%, and 72.5% for WL endoscopy and 86.5%, 84.1%, 84.1%, and 88.3% for NF-NBI endoscopy, respectively.

Tab.1 Diagnostic accuracy of conventional WL and NF-NBI endoscopy in the predication of H. pylori–infected stomach

	Sensitivity	Specificity	Positive predictive value	Negative predictive value
WL	57.7	92.1	53.0	72.5
NF-NBI	86.5	84.1	84.1	88.3

Conclusions NF-NBI endoscopy may be more useful for predicting H. pylori infection than WL endoscopy.