[Association between admission diagnosis and immunotherapy outcome in patients with autoimmune epilepsy]

To evaluate the impact of admission diagnosis on seizure outcome in patients with autoimmune epilepsy (AE).
 Methods: We conducted a retrospective study on 40 AE patients at Department of Neurology, Xiangya Hospital, Central South University from Jan. 1st, 2017 to Nov. 21st, 2018. According to their admission diagnosis, these patients were further assigned into 2 groups: An AE diagnosed group and an AE undiagnosed group. Demographic data, clinical characteristics, cerebrospinal fluid (CSF), electroencephalogram, and brain imaging were compared between the 2 groups. Favorable seizure outcome was defined as >50% reduction of seizure frequency at the first follow-up. The impact of admission diagnosis on seizure outcome of AE patients was analyzed.
 Results: The ages of 40 AE patients were (33.23±16.41) years, comprising 19 males and 21 females. No significant difference was found between the AE diagnosed group and the AE undiagnosed group in gender, age, central nervous system-specific Ab profile, CSF, and brain imaging. Duration of symptom onset to Ab detection was significantly longer in the AE undiagnosed group than that in the AE diagnosed group (P<0.01). Duration of symptom onset to immunotherapy was also significantly longer in the AE undiagnosed group than that in the AE diagnosed group (P<0.001). There were more patients with favorable seizure outcome in the AE diagnosed group than the AE undiagnosed group (P<0.05).
 Conclusion: Admission diagnosis for patients with AE is associated with seizure outcome after immunotherapy. For adult-onset epilepsy or epilepsy with unknown etiology, the diagnosis of AE should be considered. Early diagnosis of AE and prompt initiation of immunosuppressive treatment are crucial to increase the likelihood of achieving favorable seizure outcome.