Encephalitis Induced by Immune Checkpoint Inhibitors

Immune checkpoint inhibitors may induce mainly 2 different encephalitic syndromes: a focal limbic or extralimbic encephalitis and a meningoencephalitis. Immune checkpoint inhibitor-induced encephalitis is associated with an overall favorable outcome, with a low rate of fatal events. An undetected preexisting paraneoplastic encephalitic syndrome may be triggered by ICIs, and this type of syndrome has the worst outcome among all the different types of ICI-induced encephalitis syndromes. Clinical presentation and systematic measurement of autoantibodies will be a helpful guide for the therapeutic strategy and for counseling regarding prognosis.