[1] Oita Univ, Fac Med, Dept Environm & Prevent Med, 1-1 Idaigaoka,Hasama Machi, Yufu City, Oita 8795593, Japan
[2] Dhaka Med Coll & Hosp, Dept Gastroenterol, Dhaka, Bangladesh
[3] Airlangga Univ, Inst Trop Dis, Surabaya, Indonesia
[4] BIRDEM, Dept Gastroenterol, Dhaka, Bangladesh
[5] Baylor Coll Med, Dept Med, Gastroenterol & Hepatol Sect, Houston, TX 77030 USA