Prospective Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jan 21, 2015; 21(3): 982-987
Published online Jan 21, 2015. doi: 10.3748/wjg.v21.i3.982
New aspects in the pathomechanism and diagnosis of the laryngopharyngeal reflux-clinical impact of laryngeal proton pumps and pharyngeal pH metry in extraesophageal gastroesophageal reflux disease
Valentin Becker, Romina Drabner, Simone Graf, Christoph Schlag, Simon Nennstiel, Anna Maria Buchberger, Roland M Schmid, Dieter Saur, Monther Bajbouj
Valentin Becker, Romina Drabner, Simone Graf, Christoph Schlag, Simon Nennstiel, Roland M Schmid, Dieter Saur, Monther Bajbouj, II. Medizinische Klinik, Klinikum rechts der Isar, Technische Universität München, 81675 München, Germany
Anna Maria Buchberger, Hals-Nasen Ohren Klinik, Klinikum rechts der Isar, Technische Universität München, 81675 München, Germany
Author contributions: Becker V, Bajbouj M and Schmid RM are responsible for the study design; Becker V, Bajbouj M, Schlag C and Nennstiel S performed patient recruitment; Drabner R and Saur D was immunohistochemistry and histopathology; Graf S and Buchberger AM performed ENT diagnostics.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Dr. Valentin Becker, II. Medizinische Klinik, Klinikum rechts der Isar, Technische Universität München, 22 Ismaninger str., 81675 München, Germany. valentin.becker@lrz.tum.de
Telephone: +49-89-41405847 Fax: +49-89-41404816
Received: July 15, 2014
Peer-review started: July 16, 2014
First decision: August 15, 2014
Revised: August 22, 2014
Accepted: October 14, 2014
Article in press: October 15, 2014
Published online: January 21, 2015
Abstract

AIM: To determine the laryngeal H+K+-ATPase and pharyngeal pH in patients with laryngopharyngeal reflux (LPR)-symptoms as well as to assess the symptom scores during PPI therapy.

METHODS: Endoscopy was performed to exclude neoplasia and to collect biopsies from the posterior cricoid area (immunohistochemistry and PCR analysis). Immunohistochemical staining was performed with monoclonal mouse antibodies against human H+K+-ATPase. Quantitative real-time RT-PCR for each of the H+K+-ATPase subunits was performed. The pH values were assessed in the aerosolized environment of the oropharynx (DxpH Catheter) and compared to a subsequently applied combined pH/MII measurement.

RESULTS: Twenty patients with LPR symptoms were included. In only one patient, the laryngeal H+K+-ATPase was verified by immunohistochemical staining. In another patient, real-time RT-PCR for each H+K+-ATPase subunit was positive. Fourteen out of twenty patients had pathological results in DxpH, and 6/20 patients had pathological results in pH/MII. Four patients had pathological results in both functional tests. Nine out of twenty patients responded to PPIs.

CONCLUSION: The laryngeal H+K+-ATPase can only be sporadically detected in patients with LPR symptoms and is unlikely to cause the LPR symptoms. Alternative hypotheses for the pathomechanism are needed. The role of pharyngeal pH-metry remains unclear and its use can only be recommended for patients in a research study setting.

Keywords: Laryngopharyngeal reflux, Proton pump inhibitor, Gastroesophageal reflux disease, Pathomechanism

Core tip: The pathophysiology and objective diagnosis of laryngopharyngeal reflux (LPR) is still unclear. The response to standard therapy (proton pump inhibitors) is poor. Laryngeal proton pumps (H+K+-ATPase) are often considered to be potential causes of LPR. The clinical significance of laryngeal proton pumps (H+K+-ATPase) is unclear. We present the first prospective series evaluating the laryngeal H+K+-ATPase, pharyngeal pH and symptom scores in patients with LPR symptoms. Laryngeal H+K+-ATPases can only be sporadically detected, and they are unlikely to cause LPR symptoms. The role of pharyngeal pH-metry remains unclear and its use can only be recommended for patients in the research study setting.