[1] Chung Ang Univ, Chung Ang Univ Hosp, Dept Internal Med, Coll Med, Seoul, South Korea
[2] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Gastroenterol, 88,Olympic Ro 43 gil, Seoul, South Korea
[3] Univ Ulsan, Coll Med, Inflammatory Bowel Dis Ctr, Asan Med Ctr, Seoul, South Korea
[4] Univ Ulsan, Inflammatory Bowel Dis Ctr, Asan Med Ctr, Coll Med, 88 Olymp ro 43 gil, Seoul 05505, South Korea