[1] Okayama Univ, Dept Gastroenterol & Hepatol, Grad Sch Med Dent & Pharmaceut Sci, Kita Ku, 2-5-1 Shikata Cho, Okayama 7008558, Japan
[2] Sumitomo Bessi Hosp, Dept Internal Med, Niihama 7928543, Japan
[3] Fukuyama Med Ctr, Natl Hosp Org, Dept Gastroenterol, Fukuyama, Hiroshima 7208520, Japan
[4] Tsuyama Chuo Hosp, Dept Gastroenterol, Tsuyama 7080841, Japan
[5] Okayama Saiseikai Gen Hosp, Dept Internal Med, Okayama 7008551, Japan
[6] Hiroshima City Hosp, Dept Internal Med, Hiroshima 7308518, Japan
[7] Kurashiki Cent Hosp, Dept Internal Med, Kurashiki, Okayama 7108602, Japan
[8] Japanese Red Cross Soc Himeji Hosp, Dept Internal Med, Himeji, Hyogo 6708540, Japan
[9] Okayama City Hosp, Dept Internal Med, Okayama 7000833, Japan
[10] Okayama Univ Hosp, Dept Endoscopy, Okayama 7008558, Japan