Endoscopic appearance of GERD: Putative role of cell proliferation

Background. Erosive esophagitis is a frequent endoscopic feature in patients with gastro-oesophageal reflux disease. However, most of patients with heartburn/regurgitation have a non-erosive reflux disease. The reason for this heterogeneous impact of gastro-oesophageal reflux disease on oesophageal mucosa is unknown to date. Aim. To evaluate the cell proliferation status of oesophageal epithelium in both healthy normal subjects and patients with gastro-oesophageal reflux disease with or without erosions. Materials and methods. All the subjects underwent endoscopy and biopsies were taken at 5 cm from the squamo-columnar junction. Specimens were analysed both at histology and at transmission electron microscopy. Cell proliferationwas evaluated by MIB1 immunostaining. Of the 85 subjects were studied, 10 were healthy controls with normal pH-testing and macroscopical, histological and ultrastructural patterns; 37were patients with erosive esophagitis, and 38 patients with non-erosive reflux disease. Results. At histology, of the 37 patients affected by erosive esophagitis, 30 had normal mucosa and 7 showed mild oesophagitis. One patient with non-erosive reflux disease showed signs of oesophagitis at histology. At TEM, all patients with gastro-oesophageal reflux disease had ultrastructural patterns of damage i.e. dilations of intercellular spaces (DIS), and all controls had a normal ultrastructural pattern. The mean (±SD) MIB1-LI values of normal subjects and non-erosive reflux disease and erosive oesophagitis patients were 62.2% (±9.1), 29.7% (±7.2) and 16.2% (±5.2), respectively; there were significant differences among the three groups (p < 0.001). Conclusions. Oesophageal mucosa of patients with reflux symptoms presents a decrease in MIB1 immunostaining of 50% and 25% in non-erosive reflux disease and erosive esophagitis patients with respect to normal subjects.