Keywords: Autoantibody; Autoimmune encephalitis; Cerebellar ataxia; Cognitive decline; GTPase Regulator Associated with Focal Adhesion Kinase (GRAF); GTPase-activating protein 2 (ARHGAP2, N-chimerin, chimerin-1); Immunoglobulin G (IgG); Limbic encephalitis; Nadrin; Oligophrenin-like protein 1 (OPHN1L); Polyneuropathy; Rho GTPase-activating protein 10 (ARHGAP10, GRAF2); Rho GTPase-activating protein 17 (ARHGAP17); Rho GTPase-activating protein 26 (ARHGAP26); RhoGAP interacting with CIP4 homologs protein 1 (RICH-1).