Abstracts

Rationale: Autism spectrum disorder [ASD] has been associated with epilepsy; electrical status epilepticus of slow wave sleep [ESES], and various sleep disorders. However, comprehensive analysis of the characteristics of patients with ASD, epilepsy, and ESES for better classification is lacking. Methods: Our previous work included a retrospective study on patients with ESES who had been admitted to our institution for video-EEG monitoring and nocturnal high dose diazepam treatment for spike suppression. Hence, a retrospective review of the neurological, neurophysiological, and neurocognitive/behavioral characteristics of identified patients with ASD in this cohort was carried out. Results: Among 44 patients with ESES, 6 patients were found to have ASD, 3 male, 3 female, age range 7-10 years. All patients were diagnosed with epilepsy; 4 had complex partial seizures, and 3 had generalized tonic clonic seizures. Three had not been on antiepileptic medications previously. All patients had communication difficulties, learning disabilities, behavioral difficulties, while 4 had developmental delays, 3 had history of prematurity, and 3 had history of perinatal respiratory distress. All 6 had additional neurocognitive comorbidities. Most had a family history of seizures or learning disabilities. One patient had been a product of sperm donation, and one the product of sperm and egg donations. Four patients had normal brain MRIs, one had a right temporal lobe cyst and normal PET; one had white matter loss, possible cortical dysplasia and left cerebellar hypoplasia, while PET showed diminished activity in the right temporal lobe. Epileptiform discharges were most commonly found in C4 (4 patients), while discharges in F7, T3/T7, C3, P7/T5, P3 were detected in 3 patients. Spike distribution was somewhat different compared to all ESES patients. Nocturnal diazepam dosing ranged from 0.427 to 1.227 mg/kg body weight. Average diazepam dose was higher in males than females, and spike counts improved by about 5 fold after one nocturnal dose of diazepam. One patient did not return for EEG, but the rest had EEGs 2 months to 2 years later; 4 patients had complete remission of spikes with seizure freedom and gradual improvement of neurocognitive difficulties, while the last patient had initial EEG improvement followed by relapse with reduction of diazepam dose, with continuing neurocognitive comorbidities. Conclusions: ASD can be associated with focal epilepsy, ESES, and multiple neurocognitive comorbidities. Spike locations on EEG tend to overlap and render clues to cortical areas potentially involved in different comorbidities of ASD, even when imaging is normal. Spike suppression may have implications beyond seizure control. Further multicenter prospective studies are needed for better characterization and classification.