Paraneoplastic disorders of the CNS and autoimmune synaptic encephalitis.
OBJECTIVE
This article provides an update on classic paraneoplastic syndromes of the CNS and autoimmune encephalitis syndromes associated with antibodies against synaptic proteins, including the NMDA receptor, LGI1, and Caspr2, among others.


RESULTS
Most classic paraneoplastic syndromes are associated with antibodies against intracellular (onconeuronal) antigens, appear to be mediated by cytotoxic T-cell responses, and have limited response to treatment. The autoimmune synaptic disorders are associated with antibodies against extracellular epitopes, appear to be directly mediated by antibodies, and are responsive to immunotherapy. The syndromes associated with antibodies against intracellular antigens almost always occur in conjunction with cancer, and their clinical course is usually monophasic. In contrast, syndromes associated with antibodies against synaptic proteins may occur with or without cancer and often relapse.


CONCLUSIONS
The spectrum of autoimmune disorders of the CNS with distinct clinical and immunologic associations is expanding. Prompt diagnosis and treatment can result in recovery from some syndromes.
Hospital Clinic/Institute of Biomedical Investigations, University of Barcelona, Spain.
Myrna R
MR
Rosenfeld
Josep O
JO
Dalmau
D000293:Adolescent; D060426:Anti-N-Methyl-D-Aspartate Receptor Encephalitis / Q000209:etiology / Q000276:immunology*; D001323:Autoantibodies / Q000276:immunology; D001324:Autoantigens / Q000276:immunology; D001327:Autoimmune Diseases / Q000209:etiology / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020361:Paraneoplastic Syndromes, Nervous System / Q000150:complications / Q000276:immunology*; D013569:Synapses / Q000276:immunology*
D001323:Autoantibodies; D001324:Autoantigens