Voltage-gated potassium channel associated proteins In 'Non-Paraneoplastic Antibodies' Non-paraneoplastic antibodies coincidental link with the cancerAnti-glial nuclear antibody (AGNA) antibodiesNMO (aquaporin 4) antibodiesGlutamate receptor typeVoltage-gated potassium channel associated proteins Back to 'Neuroimmunology' VGKC antibodies were described few years ago and it has been established that the pathogenic targets are against the complexing proteins, mainly LGI1 and Caspr2 (see below). Testing for VGKC antibodies are no longer recommended to done in isolation, and the more specific LGI1 or Caspr2 antibodies should be checked, and correlated clinically. LGI-1 (Leucine-rich glioma inactivated protein 1) antibody Tumours: Thymoma Syndrome: Limbic encephalitis with LE with Faciobrachial-dystonic seizures CASPR2 (Contactin-associated protein 2) Tumours: Thymoma Syndrome: Limbic encephalitis, cerebellar ataxia, neuromyotonia, Morvan syndrome DPPX (Dipeptidyl-Peptidase–Like Protein-6) Tumours: Thymoma Syndrome: Limbic encephalitis with psychiatric symptoms GABARB1 (GABA receptors 1) Tumours: B cell neoplasms Syndrome: Gastrointestinal symptoms, weight loss, cognitive deficit CNS hyperexcitability Diagnosis and treatment of autoimmune encephalitis There are several antibodies which can give rise to autoimmune encephalitis (see diagram). In our lab this is done as a panel, helping to identify the antigenic target using a single assay. Antibodies are best identified by a combination of techniques (immunohistochemistry and immunofluorescence) to increase sensitivity and specificity. Patients often need immunosuppression, plasma exchange and in refractory patients B-cell depleting therapies like Rituximab (especially in NMDAR encephalitis).