[1] Hosp Sta Creu & St Pau, Dept Neurol, Neuromuscular Unit, Barcelona, Spain
[2] Hosp Sta Creu & St Pau, Lab Expt Neurol, Barcelona, Spain
[3] Hosp Sta Creu & St Pau, Dept Immunol, Barcelona, Spain
[4] Univ Autonoma Barcelona, Inst Rec HSCSP, E-08193 Barcelona, Spain
[5] Clin Puerta de Hierro, Dept Neurol, Madrid, Spain