1. Department of Gastroenterology; University of Ulsan College of Medicine, Asan Medical Center; Seoul Korea
2. Department of Infectious Disease; University of Ulsan College of Medicine, Asan Medical Center; Seoul Korea
3. Department of Radiology and Research Institute of Radiology; University of Ulsan College of Medicine, Asan Medical Center; Seoul Korea
4. Digestive Disease Center; Department of Internal Medicine; Konkuk University School of Medicine; Seoul Korea