1. Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon
2. Department of Pathology, American University of Beirut Medical Center, Beirut, Lebanon
3. Department of Pediatrics, University of Maryland, Baltimore, Maryland, USA
4. Department of Medicine, Columbia University College of Physicians and Surgeons, New York, USA
5. Division of Gastroenterology and Hepatology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA