1. College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
2. Department of Internal Medicine, Division of Gastroenterology and Hepatology, King Faisal Specialist Hospital, Riyadh, Saudi Arabia
3. College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
4. Department of Internal Medicine, King Abdulaziz University, Inflammatory Bowel Disease Unit, King Abdulaziz University Hospital, Jeddah, Saudi Arabia
5. Department of Medicine, King Fahad Specialist Hospital, Dammam, Saudi Arabia
6. Department of Internal Medicine, Section of Digestive Diseases, Yale School of Medicine New Haven, CT, USA