Gastroenterology 145 (2): 272 - 273, 2013. doi: 10.1053 / j. gastro.2013.04.057 Key Points A loss of ganglion cells in the myenteric plexus of the esophagus, thought to be viral - or autoimmune-induced, decreases esophageal peristalsis and impairs relaxation of the lower esophageal sphincter (LES).