Extended Wireless pH Monitoring Significantly Increases Gastroesophageal Reflux Disease Diagnoses in Patients With a Normal pH Impedance Study

Abstract

Background/Aims Extended wireless pH monitoring (WPM) is used to investigate gastroesophageal reflux disease (GERD) as subsequent or alternative investigation to 24-hour catheter-based studies. However, false negative catheter studies may occur in patients with intermittent reflux or due to catheter-induced discomfort or altered behavior. We aim to investigate the diagnostic yield of WPM after a negative 24-hour multichannel intraluminal impedance pH (MII-pH) monitoring study and to determine predictors of GERD on WPM given a negative MII-pH. Methods Consecutive adult patients (> 18 years) who underwent WPM for further investigation of suspected GERD following a negative 24-hour MII-pH and upper endoscopy between January 2010 and December 2019 were retrospectively included. Clinical data, endoscopy, MII-pH, and WPM results were retrieved. Fisher’s exact test, Wilcoxon rank sum test, or Student’s t test were used to compare data. Logistic regression analysis was used to investigate predictors of positive WMP. Results One hundred and eighty-one consecutive patients underwent WPM following a negative MII-pH study. On average and worst day analysis, 33.7% (61/181) and 34.2% (62/181) of the patients negative for GERD on MII-pH were given a diagnosis of GERD following WPM, respectively. On a stepwise multiple logistic regression analysis, the basal respiratory minimum pressure of the lower esophageal sphincter was a significant predictor of GERD with OR = 0.95 (0.90-1.00, P = 0.041). Conclusions WPM increases GERD diagnostic yield in patients with a negative MII-pH selected for further testing based on clinical suspicion. Further studies are needed to assess the role of WPM as a first line investigation in patients with GERD symptoms.

Review article: Diagnosis and management of laryngopharyngeal reflux

“…Prolonged wireless reflux monitoring has a higher diagnostic yield and is better tolerated when compared to 24 h impedance-pH monitoring. [26][27][28] On the other hand, 24 h impedance-pH monitoring measures flow of liquid or gas and quantifies non-acid or weakly acidic reflux events, in addition to acidic reflux events. Use of 24 h pH-monitoring alone has fallen out of favour given availability of technically superior systems.…”

“…The battery life of the wireless pH recorder enables prolonged reflux monitoring for up to 96 h. Prolonged monitoring is associated with higher diagnostic yield, ability to capture variability in daily acid exposure in patients with GERD, as well as associated with treatment outcomes. 28,[40][41][42][43][44][45] Wireless pH capsule placement is also better tolerated than transnasal catheter placement. 26,27 GERD with scores of >100 denoting severe GERD.…”