1. Assistant Professor of Medicine, Consultant Pulmonologist and Consultant-in-Charge of MICU, King Khalid University Hospital and King Saud University, P.O. Box 2925, Riyadh 11461, Saudi Arabia
2. Professor of Medicine and Consultant Gastroenterologist, King Khalid University Hospital and King Saud University, P.O. Box 2925, Riyadh 11461, Saudi Arabia
3. Professor of Medicine and Consultant Cardiologist College of Medicine, King Khalid University Hospital and King Saud University, P.O. Box 2925, Riyadh 11461, Saudi Arabia