[1] Rashid Hosp, Digest Dis Unit, Dubai 003206, U Arab Emirates
[2] Al Azhar Univ, Dept Internal Med, Cairo 11884, Egypt
[3] Almana Gen Hosp, Dept Med, Al Khobar 31952, Saudi Arabia
[4] King Faisal Specialist Hosp & Res Ctr, Dept Med, Riyadh 11564, Saudi Arabia
[5] Al Madar Med Ctr, POB 80789, Sharjah, U Arab Emirates
[6] King Saud Univ, Coll Med, Dept Med, Div Gastroenterol, Riyadh 11451, Saudi Arabia
[7] Yarmouk Univ, Dept Gastroenterol, Irbid 21163, Jordan
[8] IRCCS Osped San Raffaele, Gastroenterol & Endoscopy, I-20132 Milan, Italy
[9] Univ Vita Salute San Raffaele, I-20132 Milan, Italy
[10] Humanitas Univ, Dept Biomed Sci, I-20132 Milan, Italy
[11] Cairo Univ, Fac Med, Dept Med Pharmacol, Cairo 11559, Egypt
[12] Alexandria Univ, Med Res Inst, Immunol & Allergy Dept, Alexandria 5424041, Egypt
[13] Al Bashir Hosp, Internal Med Dept, Amman 11151, Jordan
[14] Sheikh Khalifa Med City, Gastroenterol Div, Abu Dhabi 51900, U Arab Emirates
[15] King Abdulaziz Univ Hosp, Dept Med, Jeddah 21589, Saudi Arabia
[16] Cairo Univ, Integrated Clin & Res Ctr Intestinal Disorders IC, Endem Med Dept, Gastroenterol Div, Cairo 3725121, Egypt
[17] Univ Jordan, Gastroenterol & Hepatol, Amman 11942, Jordan