1. The Northern Neuroscience Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand;
2. Department of Internal Medicine, Division of Rheumatology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand;
3. Department of Internal Medicine, Division of Neurology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand;
4. Sawanpracharak Hospital, Nakhonsawan, Thailand