1 Department of Neurology, Unité de Neurologie Inflammatoire, CRC-SEP, CHU Lille, Hôpital Roger Salengro, Lille, France. bruno.lemarchant@chu-lille.fr.
2 Study Center for Primary Immunodeficiencies, Necker Hospital for Sick Children-Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France.
3 Department of Neurology, Unité de Neurologie Inflammatoire, CRC-SEP, CHU Lille, Hôpital Roger Salengro, Lille, France.
4 Department of Pathology, CHU Lille, Lille, France.
5 Department of Neurology, CH Boulogne Sur Mer, Hôpital Duchenne, Boulogne-sur-Mer, France.
6 Department of Neurology, CHU Montpellier, Hôpital Gui de Chauliac, Montpellier, France. taiebguillaume@gmail.com.