[1] Shimane Univ, Sch Med, Dept Gastroenterol & Hepatol, Izumo, Shimane 6930021, Japan
[2] Takatsuki Gen Hosp, Takatsuki, Osaka 5691115, Japan
[3] Matsue Red Cross Hosp, Matsue, Shimane 6900886, Japan
[4] Kawasaki Med Sch, Dept Internal Med, Div Gastroenterol, Kurashiki, Okayama 7010114, Japan
[5] Kusaka Hosp, Okayama 7050021, Japan
[6] Ohumi Clin, Osaka 7080842, Japan
[7] Saga Med Sch, Dept Internal Med & Gastrointestinal Endoscopy, Saga 8490937, Japan
[8] Saga Social Insurance Hosp, Saga 8490918, Japan
[9] Hyogo Coll Med, Dept Internal Med, Nishinomiya, Hyogo 6638131, Japan
[10] Amagasaki Cent Hosp, Amagasaki, Hyogo 6610976, Japan