Combined pH-metry/impedance monitoring increases the diagnostic yield in patients with atypical gastroesophageal reflux symptoms

Background: Globus sensations, hoarseness and chronic cough are suggested to be atypical manifestations of Gastroesophageal Reflux Disease (GERD). The aim of the study was to investigate whether combined pH-metry and multichannel intraluminal impedance monitoring increases the diagnostic yield. Methods: 41 patients with atypical GERD symptoms were included in the study. Globus sensation was the dominant symptom in 23 patients (56.1%). The remaining 18 patients (43.9%) complained mainly about hoarseness or chronic cough. All patients were examined by endoscopy, dual-channel pH-metry and impedance monitoring off-therapy with proton pump inhibitors (PPI). Diagnostic yield of the respective method was determined. Results: A total of 26 patients (63.4%) had pathological findings in any method. The highest diagnostic yield was achieved by combined 24-h pH-metry/impedance measurement (61.0%), followed by solely impedance measurement (48.8%), distal pH-metry (29.3%), endoscopy (22.8%) and proximal pH-metry (17.1%). All patients with a positive PPI-test and 25% of patients (5/20) with a negative PPI-test had a pathological result in pH-metry/impedance. Conclusion: Multichannel intraluminal impedance monitoring increases the diagnostic yield for objective detection of atypical manifestation of GERD. Combined 24-h pH-metry/impedance measurement has the best diagnostic yield for detection of gastroesophageal reflux and has therefore the potential to represent a new diagnostic gold standard.