Value of adjunctive evidence from MII-pH monitoring and high-resolution manometry in inconclusive GERD patients with AET 4–6%

Abstract

Objectives: Gastro-esophageal reflux disease (GERD) is a common disease in gastroenterology outpatients. However, some patients with typical reflux symptoms does not satisfy diagnostic criteria. This study was to explore the value of adjunctive evidence from multichannel intraluminal impedance-pH (MII-pH) monitoring and esophageal high-resolution manometry (HRM) in inconclusive GERD patients with acid exposure time (AET) 4–6%. Methods: Endoscopy, MII-pH monitoring and esophageal HRM were retrospectively analyzed from consecutive patients with typical reflux symptoms in a tertiary hospital from 2013 to 2019. Patients were categorized as conclusive or inconclusive GERD according to AET. Adjunctive evidence for GERD diagnosis from Lyon Consensus were collected and analyzed. Results: Among 147 patients with typical reflux symptoms, conclusive GERD was found in only 31.97% of patients ( N = 47). The remaining 100 patients (68.03%) were inconclusive GERD, of whom 28% ( N = 28) had AET 4–6%. These patients suffered similar reflux burden and impaired esophageal movement. Inconclusive GERD patients with AET 4–6% had lots of positive adjunctive evidence from HRM and MII-pH monitoring. In receiver operating characteristic analysis, mean nocturnal baseline impedance (MNBI) and post-reflux swallow-induced peristaltic wave index (PSPWI) had an area under the curve (AUC) of 0.839 (CI: 0.765–0.913, p < 0.001) and 0.897 (CI: 0.841–0.953, p < 0.001), respectively, better than total reflux episode (AUC of 0.55, p = 0.33). When MNBI was combined with PSPWI, the AUC was elevated to 0.910 (CI: 0.857–0.963, p < 0.001). Conclusions: Inconclusive GERD patients with AET 4–6% have similar acid burden and esophagus motility dysfunction to GERD patients. MNBI and PSPWI are pivotal adjunctive evidence for diagnosing GERD when AET is borderline.

Mean Nocturnal Baseline Impedance and Post-reflux Swallow-induced Peristaltic Wave Index Could Identify Gastroesophageal Reflux Disease but pH-Impedance Metrics Alone Might Not Correlate With Proton Pump Inhibitor Response in Chinese Patients With Typical Reflux Symptoms

“… 11 - 13 There is a study from China that demonstrated that the mean PSPWi of patients with AET > 6%, between 4-6% and > 6% were 59.8%, 78.6%, and 84.1%, respectively. 5 The PSPWi in this study seems higher than previous studies, and more data of the PSPWi in different AET levels is needed.…”

“…Moreover, novel parameters, mean nocturnal baseline impedance (MNBI) could reflect esophageal mucosal barrier integrity, and post-reflux swallow-induced peristaltic wave index (PSPWi) can reflect the ability of chemical clearance. It was demonstrated that in patients with typical reflux symptoms, MNBI was lower in patients with both AET between 4-6% and > 6% than patients with AET < 4%, 5 , 7 and the same trend was found in Chinese patients with low-grade esophagitis. 8 Low MNBI (MNBI < 2292 Ω) is believed as a good supportive evidence of GERD diagnosis.…”

“…Besides, 2 studies from China (with 28 and 38 patients with AET between 4-6% respectively, and 47 and 113 patients of AET > 6% respectively) displayed the manometric and pH-impedance characteristics of the 2 groups of patients were similar. 5 , 6 More data of the Chinese patients especially with a larger sample size of the patients with AET between 4-6% are preferred to evaluate whether the threshold of AET set as 4% is reasonable.…”

Mean nocturnal baseline impedance, a novel metric of multichannel intraluminal impedance-pH monitoring in diagnosing gastroesophageal reflux disease

“…acid exposure time (AET), symptom association probability (SAP), and symptom index (SI)] in MII-pH monitoring is considered to be suboptimal. 3 – 5 AET is the most useful conventional parameter to distinguish pathological reflux from physiological reflux, but it was normal in 19% of the patients with erosive esophagitis (EE) 3 and nearly 50% of the patients with non-erosive reflux disease (NERD), 3 , 4 possibly due to the day-to-day variability of AET. 6 The diagnostic sensitivity of positive SI (SI > 50%), positive SAP (SAP > 95%), and concordant SAP/SI positivity (SAP > 95% and SI > 50%) for the diagnosis of GERD was 51.06%, 46.81%, and 36.17%, respectively.…”

“… 6 The diagnostic sensitivity of positive SI (SI > 50%), positive SAP (SAP > 95%), and concordant SAP/SI positivity (SAP > 95% and SI > 50%) for the diagnosis of GERD was 51.06%, 46.81%, and 36.17%, respectively. 5 …”