1. Clinical data For each patient, the following demographic and clinical data were systematically recorded: age, gender, neurological medical history, independence, neurological symptoms, initial evolution at discharge, treatment type and duration and follow-up data. Onset of the disease was defined as acute (<48h), sub acute (>48h and <4weeks) or chronic (>4weeks) depending on the time elapsed between the manifestation of the first symptoms and time of referral to the treating center. Response to treatment was assessed according to the treating neurologist global opinion. Relapse was defined as a recurrence of symptoms and new/enlarging lesions on cerebral MRI. Disability at the end of follow-up was defined using the modified Rankin scale (mRS) through a review of the last medical record by two neurologists (SC, XA). Outcome was dichotomized into good outcome (mRS 0 to 2) and poor outcome (3 to 6).