Ultrastructural changes in mild gastroesophageal reflux disease: results of a pilot study.

Few studies have examined the ultrastructural changes in mild reflux esophagitis. Endoscopic esophageal biopsies were obtained from 10 patients with reflux symptoms and mild endoscopic esophagitis (grade 0:3 patients, grade I: 7 patients) and 9 patients with erosive esophagitis (grade II-IV), at least 5 cm above the Z line. The biopsies were evaluated by light and transmission electron microscopy. Ultrastructural changes were present in one patient with grade 0, 7 with grade I and 9 with grade II-IV esophagitis. Four of the 10 patients with grade 0-I esophagitis and 6 of 9 with grade II-IV esophagitis had light microscopic abnormalities. The ultrastructural abnormalities in patients with mild esophagitis were seen in the cell membrane, cytoplasmic organelles, desmosomes, and nuclei of all the three layers of esophageal mucosa and the basal lamina. Ultrastructural studies by transmission electron microscopy on endoscopic pinch biopsies may be a sensitive research tool to study the pathogenesis of mild reflux esophagitis.