LGI1 and autoimmune encephalitis: Autoimmune encephalitis (AE) is an inflammatory disease that induces the production of immunoglobulin G (IgG) antibodies against extracellular (leucine rich glioma inactivated 1 [LGI1], contactin associated protein-like 2 [CASPR2], the N-methyl-D-aspartic acid receptor [NMDAR], the α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor [AMPAR], the gamma-aminobutyric acid B receptor [GABABR], etc.)and/or intracellular (glutamic acid decarboxylase-65 [GAD65], Ma2, anti-neuronal nuclear antibody type 1 [ANNA-1/Hu], etc.)neuronal antigens in the serum and/or cerebrospinal fluid.