Analysis Of Electroencephalogram Features In Patients With Autoimmune Encephalitis

Background and PurposeAutoimmune encephalitis(AE)is a series of immune-mediated diseases targeting the central nervous system.The electroencephalogram(EEG)manifestations are generally nonspecific and there is no established EEG scoring system for diagnosis so far.However,EEG is highly sensitive to the diagnosis of autoimmune encephalitis,and patients with anti-NMDAR encephalitis can show specific extreme delta brush.Therefore,the EEG manifestations of patients with autoimmune encephalitis were collected and the general manifestations and special manifestations were summarized.This study investigated whether there were specific patterns other than extreme delta brush in autoimmune encephalitis,which could be used as a supporting evidence for the clinical diagnosis,especially antibody-negative patients,so as to increase the rate of disease diagnoses.MethodsThe clinical data of 78 AE cases collected in the department of neurology in the First Affiliated Hospital of Harbin Medical University from July 2015 to December2019 were retrospectively analyzed.The EEG manifestations of patients were presented and compared to investigate its correlations with antibody subtype,symptomatology,imaging and prognosis.The EEG manifestations were observed whether there were specific patterns.According to whether the EEG showed extreme delta brush,the patients were grouped and analysed whether there were differences in the clinical data between different groups.Results1)The sensitivity of EEG to diagnose AE was higher than that of MRI and CSF;2)AE patients mostly showed non-specific abnormalities in EEG,the most common manifestation was epileptiform discharge,followed by diffuse slow activity.3)There was no significant difference among the antibody sub-types on the EEG chart.4)The incidence of clinical epileptic seizure was 3.5 times higher than that of sub-clinical seizure,and patients without epilepsy mostly showed normal or slow wave abnormal in EEG;5)There was no significant correspondence between EEG and imaging;6)There was no significant correlation between posterior head rhythm and prognosis;7)Nearly 30% of patients with anti-NMDAR encephalitis showed specific EDB pattern.ConclusionsMost AE patients showed non-specific abnormalities in EEG,the most common manifestations were epileptiform discharge and diffuse slow wave,and there was no significant correlation between EEG and antibody subtype,imaging or prognosis.EDB was specific for anti-NMDAR encephalitis.