Abstracts

Rationale: Approximately one third of patients with epilepsy are medically intractable. A subset of these patients may have an autoimmune or CNS inflammatory etiology. We report our experience at Vanderbilt University Hospital of patients suspected of having an autoimmune or inflammatory basis for seizures. Methods: Retrospective chart review study of patients seen in the Neuroimmunology Clinic between 2005 and 2015 with a suspected autoimmune or inflammatory cause for seizures. Results: A total of fourteen patients were identified including twelve women (85.7%) and two men. The average age of seizure onset was 40 years (range 12 to 65). The most common clinical presentation was alteration in mental status (encephalopathy) in four patients (28.6%). Other clinical presentations were psychosis in three patients (21.4%), cognitive symptoms in three patients (21.4%), and intractable seizures in another three patients (21.4%). Eight patients had a normal basic CSF profile (57%) whereas six patients had an inflammatory CSF. MRI Brain was essentially unremarkable in eight patients (57%) and two patients (14.3%) had acute changes on MRI Brain. The most common diagnosis was Hashimoto's encephalopathy in seven patients (50%) followed by NMDA -R encephalitis in three patients ( 21.4%), including two with paraneoplastic presentations. In three patients the diagnosis was made clinically despite no autoimmune antibodies being identified due to response to treatment. At last follow up, twelve patients (85.7%) were considered to be in remission ,seven patients (50%) continued to be on immune suppressant therapy and ten patients (71.4%) were on an anti-epileptic medication including five patients on more than one AED. Only two patients had a previous established diagnosis of epilepsy and one became seizure free on immune suppressant therapy despite previously failing to become seizure free after epilepsy surgery. Conclusions: A high index of suspicion is required to diagnose this potentially treatable seizure etiology. Funding: None