[Autoimmune synaptic encephalopathies]

Antibody-associated limbic encephalitis was usually seen as a paraneoplastic syndrome where the antibodies would target intracellular proteins. However, recent reports challenged this idea and described antibodies that target synaptic proteins expressed on the cell surface. These antibodies are not necessarily linked to tumors and should be regarded as a distinct entity of different autoimmune diseases. They are of direct clinical relevance since their binding to their target antigen is likely the cause of the clinical symptoms and, therefore, immune treatment often results in a beneficial outcome. Tests which differentiate these antibodies are now available in specialized laboratories.