Diagnostic algorithms in autoimmune encephalitis

Over the past decade the discovery of novel forms of encephalitis associated with neuronal surface antibodies had changed the paradigms for diagnosing and treating disorders that were previously mischaracterized. Recognition of clinical syndromes, consistent methods of diagnosis, and early targeted immunotherapy can lead to a favorable outcome in diseases that may be associated with significant disability or death if left untreated. Here the conditions associated with neuronal surface antibodies are briefly reviewed, some general aspects of these syndromes are considered and guidelines that could help in the recognition of these disorders are suggested. Furthermore, a diagnostic algorithm to detect and characterize neuronal cell surface autoantibodies is suggested and some of the caveats of serum testing are outlined. Future directions will involve the identification of novel autoantibodies, the standardization of methods to detect and characterize them, as well as evaluation of the most efficacious therapeutic strategies in patients with established diagnosis of autoimmune encephalitis.