Response to Electroconvulsive Therapy in a Patient With SCN2A-Variant Catatonia Is Associated With Postictal Spreading Depolarization.

An 18-year-old female patient with a history of autism spectrum disorder and SCN2A loss-of-function variant received a course of electroconvulsive therapy (ECT) for catatonia, which had been present and disabling for 1 year. After a partial lorazepam taper, bitemporal ECT was initiated. The patient had a rapid and robust response to ECT with improvement in the Bush-Francis Catatonia Rating Scale to 0 after 4 treatments and sustained catatonia remission even after lorazepam cessation. After the patient's family opted to discontinue ECT after the index course, she suffered a recurrence of her catatonia 2 months later, which remitted after a second index ECT course. The patient's brain physiology was highly stereotyped across treatments, with prominent EEG postictal suppression coinciding with cortical spreading depolarization (CSD). This case represents the fourth-ever reported case of SCN2A-associated catatonia and the oldest onset of catatonia in this population. In addition, it provides support for the emerging evidence for CSD as a potential contributor to both ECT postictal suppression and clinical response.