Effect of Postprandial Proximal Gastric Acid Pocket in Gastroesophageal Reflux Disease / 胃肠病学

ABSTRACT

Background:Postprandial proximal gastric acid pocket (PPGAP)is an unbuffered layer of high acidity in the proximal stomach postprandially. It is considered to play an important role in gastroesophageal reflux disease (GERD). Aims:To investigate the effect of PPGAP in GERD. Methods:Sixty outpatients with GERD,including 20 non-erosive reflux disease (NERD),20 mild reflux esophagitis (RE)and 20 moderate-to-severe RE from Mar. 2014 to Dec. 2016 at the Second Affiliated Hospital of Xi'an Jiaotong University were enrolled. Twenty healthy volunteers were served as controls. All the subjects underwent a high-resolution esophageal manometry in fasting state to identify the location of the lower border of the lower esophageal sphincter (LBLES). Then a station pull-through pH monitoring was performed from 5 cm below the LBLES (stomach)to the esophagus in increments of 1 cm in fasting state and repeated after a standardized meal to detect the PPGAP. Results:PPGAP was identified in all the subjects. There were no significant differences in appearing time of PPGAP among healthy volunteers and different subtypes of GERD (P ＞0.05 ). Compared with the healthy volunteers,the disappearing time of PPGAP was significantly later and the lasting time was significantly longer in patients with NERD,mild RE and moderate-to-severe RE (P＜0.05);meanwhile,the length of PPGAP was enlarged and the nadir pH and mean pH were decreased in NERD,mild RE and moderate-to-severe RE (P＜0.05). When comparison was made between different subtypes of GERD,no significant differences were observed in above-mentioned parameters (P＞0.05). Conclusions:PPGAP is present generally in normal individuals and GERD patients,and is lasting longer, more acidic and enlarged in length in GERD patients than in normal individuals. PPGAP may be the reservoir from which acid reflux events originate and contributes to the development of GERD.