A Unique Case of SCN2A Variant-Associated Catatonia and Response to Electroconvulsive Therapy.

Abstract: The SCN2A gene encodes a subunit that forms part of voltage-gated sodium channels in the brain. Gain-of-function mutations are associated with epilepsy as well as numerous movement/motor abnormalities. Loss-of-function mutations may also cause epilepsy in addition to a variety of neurodevelopmental anomalies, including autism and intellectual disability. The occurrence of catatonia has also been described in 1 previous report that involved a 4-year-old boy. We describe a 20-year-old intellectually disabled female patient who developed recurrent catatonic symptoms in her teenage years that remitted with electroconvulsive therapy. This is only the second report of catatonia occurring in relation to an SCN2A mutation and the first involving a female. Moreover, this case is unique given our patient's later age of symptom onset and given that her symptoms responded well to electroconvulsive therapy.