摘要Background:Patterns observed with electroencephalography (EEG) for patients who have encephalitis are usually known as generalized nonspecific cerebral abnormalities.The aim of this study was to investigate the presence of a special EEG pattern for patients with encephalitis and to explore features related to this special and uncommon pattern.Methods:EEG monitoring was performed for every patient aged ＞ 15 years with encephalitis who was hospitalized between December 2011 and March 2014.Clinical characteristics and EEG recordings were collected and evaluated.Results:Fifty-two patients with encephalitis were enrolled in our study with a 2-h median EEG recording time,and extreme beta brushes (EBBs) occurred in 17 patients (32.7％).Its presence was not significant regarding gender,age,psychiatric medication use,EEG rhythmic disorganization (P ＞ 0.05).Nevertheless,among the patients with EBBs,nine patients (52.9％) had epileptic seizures that had a significant detection rate (P ＜ 0.05); moreover,the cerebrospinal fluid (CSF) or serum of 15 patients (88.2％) with EBBs was positive for antibodies (P ＜ 0.05).Four patients (23.5％) who had EBB had corresponding regional distributions on neuroimaging scans.The EBBs completely correlated with the regional distributions of spike discharges for four patients.Conclusion:EBB is a special EEG pattern for patients with encephalitis,especially those with epileptic seizures or who have antibody-positive CSF/serum,and should be considered in clinical practice.