Juice Test for Identification of Nonerosive Reflux Disease in Heartburn Patients

BACKGROUND/AIMS: Evaluation of esophageal clearance by orange juice swallowing could be useful to identify different categories of gastroesophageal reflux disease. We determined whether a juice test at the beginning of esophageal pH monitoring can identify nonerosive reflux disease (NERD) among heartburn patients. METHODS: Multiple swallows of orange juice (pH 3) were performed at the beginning of esophageal pH monitoring in 71 heartburn patients off acid-suppressive therapy. The area between pH drop below 5 and recovery to 5 was calculated from pH tracings and named Delta5 (mmol·L(−1)·sec). Fifteen healthy subjects served to determine Delta5 cutoff (95th percentile). Patients were classified as NERD, non-NERD (a mix of reflux hypersensitivity, functional heartburn, and undetermined), and erosive disease depending on acid exposure, reflux symptom analysis, and upper endoscopy. RESULTS: Delta5 cutoff in healthy subjects was 251 mmol·L(−1)·sec. Among 71 patients, 23 had NERD, 26 had non-NERD, and 22 had erosive disease. Compared to non-NERD, Delta5 was higher in both NERD (median [interquartile range]: 316 [213–472] vs 165 [105–225]; P < 0.01) and erosive disease (310 [169–625] vs 165 [105–225]; P < 0.01). An elevated Delta5 (> 251 mmol·L(−1)·sec) showed sensitivity of 74% and specificity of 81% for identification of NERD. Positive and negative likelihood ratios were 3.84 and 0.32 respectively, whereas test accuracy was 78%. CONCLUSIONS: A juice test with calculation of Delta5 helps in the identification of true NERD among heartburn patients with endoscopy-negative reflux disease. In these patients, an elevated Delta5 could make prolonged reflux testing unnecessary.