BACKGROUND AND AIMS:To examine the accuracy of narrow band imaging(NBI) findings in non-erosive reflux disease(NERD) patients compared to controls and the impact of proton pump inhibitor therapy(PPI) on these mucosal changes in a multi-center, double-blind, randomized controlled trial.
METHODS:NERD patients(typical symptoms using validated GERD questionnaire, absence of erosive esophagitis and abnormal 48-hour pH study) and controls underwent high-definition white light endoscopy followed by NBI and biopsies of the distal esophagus. Then, NERD patients were randomized to esomeprazole 40 mg per day or placebo for 8 weeks, followed by repeat endoscopy. Presence of distal esophageal mucosal changes on NBI were recorded at baseline and after treatment - intrapapillary capillary loops(IPCL; number, dilation, and tortuosity), micro-erosions, increased vascularity, columnar islands, and ridge villous pattern(RVP) above squamocolumnar junction.
RESULTS:Of 122 screened, 21 NERD and 21 controls were identified: age 49.5+/- 14.6years, 62%males, 85%Caucasians. Combination of IPCL tortuosity, RVP and micro-erosions(62% vs 19%, p<0.05) had a high specificity(86%) and moderate sensitivity(60%) for NERD with an area-under-the-curve=0.74. In NERD patients treated with PPI(n=10), resolution of micro-erosions was most significant(p=0.047) compared to placebo(n=11). RVP resolved in all NERD patients after therapy(p=0.02) and correlated with acid exposure time(p=0.004). Papillary length(p=0.02) and basal cell thickness(p=0.02) significantly correlated with a combination of IPCL tortuosity, RVP and micro-erosions.
CONCLUSIONS:In this RCT, ridge-villous pattern on NBI demonstrated a high specificity, correlated with acid exposure time and improved with proton pump inhibitor therapy suggesting that it could be used as a surrogate marker for diagnosis of non-erosive reflux disease.(Clinicaltrials.gov: NCT02081404).