Gastroesophageal reflux disease (GERD) is defined as a condition which develops when the reflux of gastric contents causes troublesome symptoms and long-term complications. GERD can be divided into erosive reflux disease and non-erosive reflux disease based on endoscopic findings defined by the presence of mucosal break. The Los Angeles classification excludes minimal changes as an evidence of reflux esophagitis because of poor interobserver agreement. In the Asian literature, minimal changes are considered as one of the endoscopic findings of reflux esophagitis, but the clinical significance is still controversial. Minimal change esophagitis is recognized quite frequently among patients with GERD and many endoscopists recognize such findings in their clinical practice. This review is intended to clarify the definition of minimal change esophagitis and their histology, interobserver agreement, and symptom association with GERD.
Esophagitis/pathology ; Esophagoscopy ; Gastroesophageal Reflux/classification/*diagnosis ; Humans ; Mucous Membrane/pathology

BACKGROUND/AIMS: Interobserver variation by experience was documented for the diagnosis of esophagitis using the Los Angeles classification. The aim of this study was to evaluate whether interobserver agreement can be improved by higher levels of endoscopic experience in the diagnosis of erosive esophagitis. METHODS: Endoscopic images of 51 patients with gastroesophageal reflux disease (GERD) symptoms were obtained with conventional endoscopy and optimal band imaging (OBI). Endoscopists were divided into an expert group (16 gastroenterologic endoscopic specialists guaranteed by the Korean Society of Gastrointestinal Endoscopy) and a trainee group (individuals with fellowships, first year of specialty training in gastroenterology). All endoscopists had no or minimal experience with OBI. GERD was diagnosed using the Los Angeles classification with or without OBI. RESULTS: The mean weighted paired kappa statistics for interobserver agreement in grading erosive esophagitis by conventional endoscopy in the expert group was better than that in the trainee group (0.51 vs 0.42, p<0.05). The mean weighted paired k statistics in the expert group and in the trainee group based on conventional endoscopy with OBI did not differ (0.42, 0.42). CONCLUSIONS: Interobserver agreement in the expert group using conventional endoscopy was better than that in the trainee group. Endoscopic experience can improve the interobserver agreement in the grading of esophagitis using the Los Angeles classification.
Clinical Competence/*standards ; Esophagitis/classification/*pathology ; Esophagoscopy/*standards ; Gastroenterology/*standards ; Gastroesophageal Reflux/classification/pathology ; Humans ; Observer Variation ; Retrospective Studies