Background and aim: Oxidative stress to esophageal mucosa plays a key role in the pathogenesis of gastroesophageal reflux disease (GERD), Barrett's esophagus, and adenocarcinoma. We investigated whether successful antireflux surgery eliminates oxidative stress.
Methods: Oxidative stress of esophageal mucosa was measured in 20 GERD patients, before antireflux surgery and 6 and 48 months after it, and compared with normal controls' mucosa (N = 9). Preoperatively, 12 of the 20 had erosive esophagitis or Barrett's metaplasia. Postoperatively, healing of GERD was verified with endoscopy and 24-h pH monitoring. We measured oxidative stress by myeloperoxidase activity (MPA), superoxide dismutase activity, and glutathione content (GSH) in distal esophagus samples from endoscopy.
Results: No patient had reflux symptoms after surgery, and pH measurements had normalized. MPA in the distal esophagus decreased (p < 0.05) after successful antireflux surgery, but remained higher than that of controls both 6 months and 4 yr postoperatively (p < 0.05). At all time-points, MPA was higher in patients with preoperatively detected erosive reflux disease (ERD) as compared to non-erosive reflux disease (NERD) (p < 0.01, p < 0.05, and p < 0.05, respectively). GSH values decreased with time only in NERD. At all time-points, GSH levels in distal esophagus were lower than control levels.
Conclusions: Antireflux surgery can heal macroscopic esophagitis but cannot fully reverse the oxidative stress (as reflected by MPA and GSH) upon the distal esophageal mucosa.