In this retrospective study, we searched our medical record system for patients discharged with diagnosis of encephalitis  from hospital, years 2005-2020 (N=350). Then all patients with a history of seizure at presentation or during admission  were identified (N=114). Their clinical and EEG features were extracted. We followed them in outpatient EMR to recognize the ones diagnosed with auto-immune epilepsy vs acute symptomatic epilepsy.

Seventy eight patients had an EEG during admission, 44.8% being longterm continuous EEG. In five patients, status epilepticus was captured on EEG.  23.6% of patients had auto-immune related seizures proven by antibodies or biopsy, while 43.8% of cases were infectious. On follow up, only 29 had follow up in our medical records, 15 of which were diagnosed with immune-related epilepsy. The most common cause of epilepsy in this group of patients was autoimmune (p<0.05) with NMDAR antibody being the most frequent type.

In our study, clinical outcome of epilepsy was mainly encountered among patients with auto-immune encephalitis than infectious. Moreover, contrary to prior studies, NMDAR was the most common cause of auto-immune related epilepsy. We would like to emphasize on  the importance of longterm follow up of patients with autoimmune seizures in clinic. Given the large number of lost to follow up patients, presence of multidisciplinary clinics would be helpful for providing better patient care.