Autoimmune encephalopathy (Q84126)

Autoimmune encephalopathy is similar to autoimmune encephalitis [see autoimmune encephalitis definition] but reflects a more subacute to insidious onset which tends to fluctuate and often mimics neurodegenerative dementias (Creutzfeldt-Jakob disease or Lewy Body disease). A personal or family history of autoimmunity is often found. Investigations typically show an inflammatory spinal fluid, an epileptiform electroencephalogram and MRI abnormalities in the mesial temporal lobes. Accompanying neural autoantibodies (e.g. voltage gated potassium channel complex autoantibodies) and non-organ specific (thyroid peroxidase [TPO] antibodies) may be found. Exclusion of alternative etiologies (e.g. infections) is important. Response to immunotherapy may be used to confirm the diagnosis. Associated autoantibodies: DPPX (dipeptidyl-peptidase–like protein-6); GABAAR (Gamma-aminobutyric-acid type-A autoantibodies); gAChR (ganglionic acetylcholine receptor autoantibodies (alpha-3 subunit)); GAD65 (glutamic acid decarboxylase-65 antibodies); VGKC (LGI1, CASPR2) (voltage gated potassium channel complex antibodies ).