Stereo-EEG associated anti-GAD65 autoimmune encephalitis – A report of two cases

Abstract

We present two cases of adult-onset temporal lobe epilepsy (TLE) who underwent stereo-EEG and, within weeks of explantation, experienced subacute encephalopathy and in one patient, seizure exacerbation. Diagnostic investigations revealed low titer GAD antibodies in serum and evidence of GAD intrathecal synthesis. Immunotherapy led to improvement in one patient. We posit a role for blood brain barrier disruption in the setting of a neurosurgical procedure leading to inflammation and intrathecal synthesis of GAD antibodies. Investigations for autoimmune causes of epilepsy should be undertaken prior to SEEG in patients with no known cause of epilepsy and a suggestive electroclinical phenotype.