1Department of Gastroenterology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan
2Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
1Department of Gastroenterology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan
2Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea