Voltage gated potassium channel (VGKC) antibody encephalitis
Voltage gated potassium channel (VGKC) antibody encephalitis is an autoimmune encephalitis with antibodies against the voltage gated potassium channel. It is one of the most common forms of autoimmune limbic encephalitis in the absence of primary extra-CNS tumours. Autoimmune VGKC encephalitis can be diagnosed by serologic testing and is potentially treatable with immunotherapy. Most patients present with seizures and epilepsy in the absence of memory loss and neuropsychiatric symptoms which are more common in limbic encephalitis.
One study showed that majority of the proven patients had unilateral or bilateral amygdala with or without hippocampal enlargement and T2 hyperintensity at some time point during the course of the disease. Also, restricted diffusion and mild ill-defined enhancement demonstrated in approximately 50% and 25% of patients, respectively. Extratemporal involvement is rare. In the long term, mesial temporal sclerosis may be seen as high as 50% of patients 1.
- 1. Kotsenas AL, Watson RE, Pittock SJ et-al. MRI findings in autoimmune voltage-gated potassium channel complex encephalitis with seizures: one potential etiology for mesial temporal sclerosis. AJNR Am J Neuroradiol. 2014;35 (1): 84-9. doi:10.3174/ajnr.A3633 - Pubmed citation
- 2. Finelli PF. Autoimmune Limbic Encephalitis With GAD Antibodies. Neurohospitalist. 2011;1 (4): 178-81. doi:10.1177/1941875211413135 - Free text at pubmed - Pubmed citation
- 3. Parthasarathi UD, Harrower T, Tempest M et-al. Psychiatric presentation of voltage-gated potassium channel antibody-associated encephalopathy. Case report. Br J Psychiatry. 2006;189 (2): 182-3. doi:10.1192/bjp.bp.105.012864 - Free text at pubmed - Pubmed citation