1. Department of Gastroenterology, Iwata City Hospital, Iwata, Japan
2. Department of Gastroenterology, Asahi Rosai Hospital, Owariasahi, Japan
3. Department of Internal Medicine II, Hamamatsu University School of Medicine, Higashi-Ku, Japan
4. First Department of Medicine, Hamamatsu University School of Medicine, Higashi-Ku, Japan