Gastroesophageal sphincter pressure and histological changes in distal esophagus in patients with achalasia of the esophagus.

A prospective study was performed in 17 patients with achalasia of the esophagus determining the manometric characteristics of the gastroesophageal sphincter, correlating it with histological analysis by biopsies taken during surgery at the distal narrowed segment of the esophagus, at the location of the sphincter. The histological findings were compared to 10 control cases. Presence or absence of ganglion cells at the Auerbach's plexuses and appearance of smooth muscle fibers were evaluated. Only one case (6%) had Chagas' disease. The mean sphincter pressure was 41 mm Hg, with incomplete relaxation in all patients. Histological analysis showed a complete disappearance of ganglion cells in 94% of the cases and a decrease in the number of neurons with marked chronic inflammatory cells in one case (6%). In all control cases, the ganglion cells were normal. Smooth muscle fibers were normal on light microscopy. No relationship was found between resting gastroesophageal sphincter pressure, length and relaxation, and histological findings at the distal esophagus. These findings suggest that the denervation in the majority of cases is located in the Auerbach plexus, with complete absence of ganglion cells and, therefore, absence of postganglionic nerve fibers.