1 Gastrointestinal Endoscopy Excellence Center, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand.
2 Pancreas Research Unit, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
3 Division of Gastroenterology, Department of Medicine, Faculty of Medicine, Phramongkutklao Hospital, Phramongkutklao College of Medicine, Bangkok, Thailand.