The diagnosis of autoimmune encephalitis is based on the exclusion of differential diagnosis. The first step is a clinical evaluation Biochemical tests may reveal hyponatremia and the other features of SIADH. Relevant supplementary tests are listed in table 1. The diagnosis of<unk><unk>  associated limbic encephalitis should be suspected in both men and women presenting with subacute debut of disorientation, confusion and amnesia especially when associated with seizures and signal change of the medial temporal lobe on MRI. Investigation methods Comments MRI Exclusion of differential diagnosis (e.g. cerebrovascular disease). Hyperintensity of affected regions on T2-images is characteristic. Sensitivity 60-84 %. EEG Exclusion of differential diagnosis. Non-characteristic findings may be found in autoimmune encephalitis. Lumbar puncture Exclusion of differential diagnosis (e.g. infectious diseases). Abnormalities may be found in autoimmune encephalitis. Immunofluorescence/immunohistochemistry On mammalian brain. Rodent hippocampal culture Cell based assays Using cell lines (e.g. HEK 293) transfected with recombinant proteins. Commercial products exists. Radioimmunoassay Non specific. Have the ability to detect antibodies towards undescribed<unk><unk>  associated antigens. The<unk>  probably contains unidentified antigens since about 20% of patients have antibodies which can’t be detected with the more specific assays.
Anti-VGKC-complex encephalitis
Anti-NMDA receptor encephalitis
Anti-Hu associated encephalitis
Anti-neurofascin demyelinating diseases
Lymphocytic meningoradiculitis
Limbic encephalitis
Powassan encephalitis
Autoimmune encephalitis