Volume, distribution and acidity of gastric secretion on and off proton pump inhibitor treatment: a randomized double-blind controlled study in patients with gastro-esophageal reflux disease (GERD) and healthy subjects.
BACKGROUND
Postprandial accumulation of gastric secretions in the proximal stomach above the meal adjacent to the esophagogastric junction (EGJ), referred to as the 'acid pocket', has been proposed as a pathophysiological factor in gastro-esophageal reflux disease (GERD) and as a target for GERD treatment. This study assessed the effect of proton pump inhibitor (PPI) therapy on the volume, distribution and acidity of gastric secretions in GERD and healthy subjects (HS).


METHODS
A randomized, double blind, cross-over study in 12 HS and 12 GERD patients pre-treated with 40 mg pantoprazole (PPI) or placebo b.i.d. was performed. Postprandial secretion volume (SV), formation of a secretion layer and contact between the layer and the EGJ were quantified by Magnetic Resonance Imaging (MRI). Multi-channel pH-monitoring assessed intragastric pH.


RESULTS
A distinct layer of undiluted acid secretion was present on top of gastric contents in almost all participants on and off high-dose acid suppression. PPI reduced SV (193 ml to 100 ml, in HS, 227 ml to 94 ml in GERD; p < 0.01) and thickness of the acid layer (26 mm to 7 mm, 36 mm to 9 mm respectively, p < 0.01). No differences in secretion volume or layer thickness were observed between groups; however, off treatment, contact time between the secretion layer and EGJ was 2.6 times longer in GERD compared to HS (p = 0.012). This was not the case on PPI.


CONCLUSIONS
MRI can visualize and quantify the volume and distribution dynamics of gastric secretions that form a layer in the proximal stomach after ingestion of a liquid meal. The secretion volume and the secretion layer on top of gastric contents is similar in GERD patients and HS; however contact between the layer of undiluted secretion and the EGJ is prolonged in patients. High dose PPI reduced secretion volume by about 50% and reduced contact time between secretion and EGJ towards normal levels.


BACKGROUND
NCT01212614.
Division of Gastroenterology and Hepatology, University Hospital Zurich, Raemistrasse 100, CH-8091, Zurich, Switzerland. steingoetter@biomed.ee.ethz.ch.|Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse 35, CH-8092, Zurich, Switzerland. steingoetter@biomed.ee.ethz.ch.
Andreas
A
Steingoetter
Division of Gastroenterology and Hepatology, University Hospital Zurich, Raemistrasse 100, CH-8091, Zurich, Switzerland. matthias.sauter@usz.ch.
Matthias
M
Sauter
Division of Gastroenterology and Hepatology, University Hospital Zurich, Raemistrasse 100, CH-8091, Zurich, Switzerland. curcic@biomed.ee.ethz.ch.
Jelena
J
Curcic
Division of Gastroenterology and Hepatology, University Hospital Zurich, Raemistrasse 100, CH-8091, Zurich, Switzerland. liu@biomed.ee.ethz.ch.|Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse 35, CH-8092, Zurich, Switzerland. liu@biomed.ee.ethz.ch.
Dian
D
Liu
Menne Biomed Consulting, Olgastr. 7, D-72074, Tübingen, Germany. dieter.menne@menne-biomed.de.
Dieter
D
Menne
Division of Gastroenterology and Hepatology, University Hospital Zurich, Raemistrasse 100, CH-8091, Zurich, Switzerland. michael.fried@usz.ch.
Michael
M
Fried
Division of Gastroenterology and Hepatology, University Hospital Zurich, Raemistrasse 100, CH-8091, Zurich, Switzerland. dr.mark.fox@gmail.com.
Mark
M
Fox
Division of Gastroenterology and Hepatology, University Hospital Zurich, Raemistrasse 100, CH-8091, Zurich, Switzerland. gasschwi@usz.uzh.ch.
Werner
W
Schwizer
D053799:2-Pyridinylmethylsulfinylbenzimidazoles / Q000008:administration & dosage / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004943:Esophagogastric Junction; D005260:Female; D005750:Gastric Juice / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism; D005764:Gastroesophageal Reflux / Q000188:drug therapy* / Q000378:metabolism*; D064368:Healthy Volunteers; D006801:Humans; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D000077402:Pantoprazole; D019518:Postprandial Period / Q000187:drug effects* / Q000502:physiology; D054328:Proton Pump Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D013997:Time Factors; D055815:Young Adult
D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D054328:Proton Pump Inhibitors; D000077402:Pantoprazole