[Pathogenesis of GERD--peculiarity of NERD].

Gastroesophageal reflux disease can be divided into two groups, reflux esophagitis and non-erosive reflux disease, according to the presence of esophageal mucosal breaks. Almost all the reflux esophagitis with mucosal breaks are caused by the pathological reflux of acidic gastric contents to esophagus. Therefore, drugs that suppress gastric acid secretion effectively control reflux symptoms. On the other hand, almost 40% of nonerosive reflux disease are not caused by the reflux of gastric acid but by acid-unrelated mechanisms. Therefore, administration of proton pump inhibitors cures reflux symptom of only 50% of cases with non-erosive reflux diseases. The multi-pathogenesis of nonerosive reflux disease should be considered for the treatment of patients with reflux symptoms.