Inclusion Criteria:  All patients living and/or treated in Switzerland with an IBrainD specified in the following list with a disease onset before the age of 18.  Written informed consent by patients (and/or legal representative(s), if applicable) Optic Neuritis Transverse Myelitis Acute disseminated encephalomyelitis Multiple Sclerosis Neuromyelitis Optica Spectrum Disorders Anti-NMDA-R Encephalitis Anti-GAD65 Associated Autoimmune Encephalitis Anti-AMPAR-1/2 Associated Autoimmune Encephalitis Anti-Lgi-1 Associated Autoimmune Encephalitis Anti-CASPR-2 Associated Autoimmune Encephalitis Anti-GABAR-1/2 Associated Autoimmune Encephalitis Onconeuronal Antibody (Hu, Ri, Yo, Amphiphysin, CRMP-5, Ma-1, Ma-2, SOX-1) Associated Autoimmune Encephalitis Hashimoto Encephalopathy CNS Vasculitis CNS Sarcoidosis CNS Lupus Rasmussen Encephalitis  Exclusion Criteria:  Neurological symptoms due to infectious diseases of the CNS Genetic/metabolic causes of central demyelinating diseases Neurological symptoms due to Guillain-Barré-Syndrome