1. Neurology Department, Cairo University, Cairo, Egypt
2. Department of Clinical and Chemical Pathology, Cairo University, Cairo, Egypt
3. Department of Tropical Diseases, Cairo University, Cairo, Egypt
4. Neurology Department, Fayoum University, Fayoum, Egypt
5. Rashid Hospital, Dubai, United Arab Emirates
6. Neurology Department, Beni-Suef University, Beni-Suef, Egypt