Profound Amnesia after Temporal Lobectomy: An Autoimmune Process Resembling Patient H.M.?

We describe a patient who developed significant cognitive decline with profound amnesia following non-dominant temporal lobectomy for refractory seizures, in whom the original suspicion of structural pathology was revised following the discovery of clinical and neuropathological markers of inflammation, neuropsychological evidence of bilateral involvement, and high titres of antibodies directed against glutamic acid decarboxylase (GAD). This case adds to the evidence that the diagnosis of non-paraneoplastic anti-GAD limbic encephalitis merits consideration in any patient with a refractory seizure disorder and cognitive decline.