Longitudinal EEG Characteristics of Anti-GAD65 Antibody Related Autoimmune Epilepsy

There is limited evidence on the management of patients with glutamic acid decarboxylase (GAD) antibody associated autoimmune epilepsy, or GAD positive (GAD+) epilepsy. We describe six GAD + epilepsy patients presenting with seizure and refractory status epilepticus with special emphasis on the longitudinal electrographic changes in relationship to immunologic and anti-seizure medication therapies. All patients presented with new onset seizure with four patients having refractory status epilepticus. Serial prolonged continuous EEG changes before and after immunotherapy were collected which demonstrated electrographic seizures are often pharmacoresistent and immunotherapy can result in seizure cessation and improvement of interictal discharges prior to clinical improvement. Our findings suggested GAD + epilepsy was controlled more effectively with immunotherapy than ASMs and serial prolonged continuous EEG monitoring can serve as a biomarker for disease outcome.