Gastroesophageal reflux is a physiological phenomenon but becomes pathological if troublesome symptoms and/or complications occur.
Gastroesophageal reflux disease (
GERD) has different phenotypes ranging from
non-erosive reflux disease (NERD), through
reflux esophagitis and
Barrett's esophagus, and can present with either typical symptoms such as regurgitation and
heartburn, or extra-esophageal symptoms such as
cough and
laryngitis. In the diagnosis of
GERD endoscopy, empirical PPI test, and pH impedance testing all have their own position. Although
proton pump inhibitors (PPIs) are very effective in the treatment of
esophagitis, a significant proportion of patients have persistent symptoms even during high dosing of PPIs. Therefore, insight into the multifactorial pathophysiology of
GERD is needed to develop new anti-reflux
therapies. The predominant mechanism underlying reflux is the transient lower esophageal sphincter relaxation (TLESR).
Hiatal hernia, impaired esophageal clearance and reduced lower esophageal sphincter pressure play a significant role in patients with moderate to severe reflux disease. Refluxate containing
acid,
pepsin and bile can cause epithelial injury when epithelial barrier of the esophagus fails to defend. In the majority of patients there is histopathological evidence of epithelial injury, even with NERD where there are more dilated intercellular spaces. The perception of
heartburn can be enhanced due to visceral
hypersensitivity, leading to more and more severe symptoms. Anti-reflux surgery is as effective as PPI
therapy, but has higher morbidity and results decline in the long term. Therefore, new pharmacological, endoscopic and surgical interventions are being developed for these patients.