Clinical characteristics analysis of autoimmune encephalitis with epileptic seizure

Objective To analyze the seizure characteristics of epilepsy in the course of different types of autoimmune encephalitis (AE), and to screen the markers of early diagnosis value. Methods A total of 91 patients with AE with epileptic seizure admitted to Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from August 2014 to January 2021 were collected. The clinical data included social demographic data, pathogenic characteristics, EEG and imaging characteristics, treatment and prognosis. Results 1) Anti⁃N⁃methyl⁃D⁃aspartate receptor (NMDAR) encephalitis (n=58), anti⁃γ⁃aminobutyric acid receptor type B (GABABR) antibody⁃associated encephalitis (n=12) and anti⁃leucine rich glioma inactivated protein 1 (LGI1) antibody⁃associated encephalitis (n=12) were common types of AE. 2) Rapid progressive dementia [79.12% (72/91)], sleep disorders [79.12% (72/91)] and mental disorders [75.82% (69/91)] were the main non⁃epileptic symptoms, but mood disorders or speech disorders were rare. 3) In the course of encephalitis, 76.92% (70/91) of patients had generalized tonic⁃clonic seizure (GTCS), which were the characteristic seizure type of anti⁃GABABR antibody⁃associated encephalitis (12/12). While faciobrachial dystonic seizure (FBDS) was the specific seizure type of anti⁃LGI1 antibody⁃associated encephalitis [4.40% (4/91)]. 4) The main manifestations of VEEG were background slow waves [37.88% (25/66)], slow waves combined with epileptic discharges [27.27% (18/66)] or epileptic discharges [18.18% (12/66)], but the increase of fast wave activity [1.52% (1/66)] was rare. There was also no abnormal brain wave [15.15% (10/66)]; δ brush was observed in only 2 patients with anti⁃NMDAR encephalitis. 5) MRI abnormalities [58.89% (53/90)] were mainly found in hippocampus amd temporal lobe, characterized by T2WI and FLAIR hyperintersity, mainly in patients with anti⁃LGI1 antibody⁃associated encephalitis (9/12). 6) Immunotherapy [97.80% (89/91)] and antiepileptic seizure medicine [94.51% (86/91)] were the preferred treatment options. The mean follow⁃up was 48.50 months, and the fatality rate was 14.29% (10/70), with the highest rate of anti⁃GABABR antibody⁃associated encephalitis (4/9). The recurrence rate of epilepsy was 10.17% (6/59), and the long⁃term recurrence rate of anti⁃DPPX antibody⁃associated encephalitis was relatively high (2/3). Conclusions Different types of AE with epileptic seizure have specific clinical characteristics, which is of great significance for early diagnosis and prognosis.