1. Faculty of Medicine, Minia University, Minia, Egypt
2. Faculty of Medicine, Mansoura University, Mansoura, Egypt
3. El Sheikh Zayed Specialized Hospital, Giza, Egypt
4. Sulaiman Al Rajhi University, College of Medicine, Qassim, Saudi Arabia
5. Department of Internal Medicine and Division of Digestive Diseases, College of Medicine, University of Kentucky, USA
6. Department of Clinical Pathology-Hematology and Ain Shams Medical Research Institute (MASRI), Faculty of Medicine, Ain Shams University, Ain Shams, Egypt