Abstracts

Rationale: Deep brain stimulation (DBS) was approved in the United States for refractory epilepsy in 2018.^[1,2] Yet the question remains if DBS would be beneficial in autoimmune epilepsy. While some autoimmune epilepsy patients are able to achieve seizure freedom with immunotherapy, many continue to remain intractable. Other treatment options including neuromodulation should be considered.^[3] We report a case of DBS placement in a patient with refractory seronegative autoimmune epilepsy.

Methods: N/A

Results: The patient is a 37-year-old left-handed male with a three-year history of epilepsy who initially presented with a cluster of six seizures within a 24-hour period to an outside hospital. He established care at University of Texas Southwestern (UTSW) Medical Center 3 months after onset. Due to an antibody prevalence in epilepsy score (APES) score of 4, empiric treatment for autoimmune epilepsy was initiated with intravenous immunoglobulin (IVIG) 0.5 g/kg/day and methylprednisolone (IVMP) 1 g/day for 5 days. Only 3 out of 5 doses of IVIG were administered due to concern for partial IgA deficiency of < 50 mg/dL (normal 70-400 mg/dL). He was discharged on an oral steroid taper and was seizure free for one month with recurrence after steroids were weaned off. Given his initial response to immunotherapy, he was presumed to have seronegative autoimmune epilepsy. He was initiated on oral prednisone for 10 months and mycophenolate for 12 months without significant clinical improvement.

Considering the poor response to further immunotherapy, stereoelectroencephalography (SEEG) was pursued and reported inconclusive findings. A neuromodulating device was recommended. The patient agreed to DBS implantation of the anterior nucleus of the thalamus. 6 months after implantation, he reported significant improvement in his seizure frequency. The focal impaired aware seizures occur once every 2 weeks and generalized convulsions occurring once every 6 months. This suggested a greater than 50% reduction in this seizure frequency.

Conclusions: The use of DBS should be considered a modality of treatment for patient with autoimmune epilepsy who are unable to achieve seizure freedom with immunotherapy and are not candidates for surgical resection.

References:
1. Li MCH, Cook MJ. Deep brain stimulation for drug-resistant epilepsy. Epilepsia [online serial]. Wiley; 2017;59:273–290.
2. Boon P, Vonck K, De Herdt V, et al. Deep Brain Stimulation in Patients with Refractory Temporal Lobe Epilepsy. Epilepsia [online serial]. Wiley; 2007;48:1551–1560.
3. Gillinder L, Lehn A, Papacostas J, Olson S, Blum S, Dionisio S. Refractory epilepsy secondary to anti-GAD encephalitis treated with DBS post SEEG evaluation: a novel case report based on stimulation findings. Epileptic Disorders [online serial]. John Libbey Eurotext; 2018;20:451–456.

Funding: Please list any funding that was received in support of this abstract.: None.