[1] Catholic Univ Korea, Coll Med, St Vincents Hosp, Div Gastroenterol,Dept Internal Med, Seoul, South Korea
[2] Catholic Univ Korea, Coll Med, Dept Internal Med, Div Gastroenterol,Incheon St Marys Hosp, Seoul, South Korea
[3] Catholic Univ Korea, Coll Med, Dept Internal Med, Div Gastroenterol,Incheon St Marys Hosp, 665 Bupyeong Dong, Incheon 403720, South Korea