Fig. 1.

Overview of different aetiologies and overlapping pathophysiological mechanisms of autoimmune encephalitis (AIE), acute symptomatic seizures secondary to autoimmune encephalitis (ASSAE), autoimmune-associated epilepsy (AAE) and epilepsy leading to seizures. Aetiologies of immune-mediated seizures can be grouped into two main categories, (1) paraneoplastic (e.g., in teratoma or small cell lung cancer), and (2) non-paraneoplastic encompassing (a) infectious (e.g. in herpes simplex 1 encephalitis or varicella zoster virus encephalitis), (b) systemic/CNS autoimmune disorders (e.g., in multiple sclerosis or systemic lupus erythematosus), and (c) genetic predisposition (e.g., HLA-associated anti-LGI1 encephalitis). All of the aetiologies can lead to common pathophysiological mechanisms, such as the production of pathogenic autoantibodies, inflammation and subsequent structural damage, which then manifest in seizures in the context of AIE, ASSAE, AE and epilepsy. Figure was created using Biorender.