Physiopathologie du reflux gastro-œsophagien

Gastro-œsophageal reflux (GORD) is a multifactorial disease. The key factor in the pathogenesis of GORD is a disordered function of the lower oesophageal sphincter (LOS). Before the description of the dynamics of LOS function, a chronically decreased LOS pressure was considered to be the most important pathogenic mechanism. Then, transient relaxations of the LOS were found to be the most prevalent mechanism of reflux episodes. Recent investigations have pointed out the role of the crural diaphragm which strengthens the LOS in the absence of a hiatus hernia. All of altered oesophageal motility leading to an impaired oesophageal clearance, delayed gastric emptying, abnormal composition of the refluxate and abnormalities in the defensive capacity of the oesophageal mucosa are also important factors in the onset of symptoms and reflux oesophagitis.