Abstract: Objective To summarize the clinical manifestations, patients with symptomatic episodes of anti-leucine rich glioma inactivated 1 (LGI1) antibody-associated encephalitis (hereinafter referred to as anti-LGI1 antibody-associated encephalitis). Methods and Results The clinical data of 41 patients diagnosed with anti-LGI1 antibody-associated encephalitis with symptomatic episodes from March 2019 to March 2022 in Beijing Tiantan Hospital, Capital Medical University were retrospectively analyzed. 1) Clinical features: onset of symptomatic seizures in the early stage of encephalitis in the form of epileptic seizure [34.15% (14/41)], faciobrachial dystonic seizures [FBDS, 17.07% (7/41)] or both [48.78% (20/41)]. 2) Imaging features: the vast majority of patients present with typical unilateral or bilateral medial temporal lobe structures including amygdala and hippocampus, parahippocampal gyrus T₂WI and FLAIR hypersignal [87.80% (36/41)], and/or amygdala swelling [65.85% (27/41)]. 3) EEG characteristics: in the interattack period, slow EEG background was observed [53.66% (22/ 41)], including diffuse and widespread slow-wave activity background [50% (11/22)]. The epileptoid discharges were unilateral (n = 8) or bilateral (n = 6), or bilateral multifocal, and some patients could still have periodic epileptoid discharges [12.20% (5/41)]. VEEG recordings showed symptomatic seizures [78.05% (32/41)] and FBDS of 59.38% (19/32), of which 3 cases presented faciobrachial dystonic seizures superposition (FBDS+). Epileptic seizure and subclinical seizures were 46.88% (15/32) and 12.50% (4/32), respectively. 4) Drug therapy: all patients received immunotherapy in addition to antiepileptic seizure medicine (ASM), including glucocorticoid combined with intravenous immunoglobulin [IVIg, 78.05% (32/ 41)], glucocorticoid alone [12.20% (5/41)] or IVIg therapy [9.75% (4/41)]. A small number of patients were supplemented with the immunosuppressive agent mortemycophenolate [14.63% (6/41)]. 5) Prognosis: a total of 37 patients were followed up for (21.36 ±11.53) months. The total seizure-free rate was 86.49% (32/37), and 56.76% (21/37) of patients stopped using ASM. Conclusions Symptomatic episodes of encephalitis associated with anti -LGI1 antibody were characterized by temporal lobe or perilateral fissure. FBDS is the most characteristic clinical manifestation. All patients should start immunotherapy as early as possible to improve the rate of good prognosis.

Key words: Encephalitis, Autoimmune diseases, Epilepsy, Electroencephalography, Immunotherapy

摘要： 目的 总结抗富亮氨酸胶质瘤失活蛋白1 抗体相关脑炎（以下简称抗LGI1 抗体相关脑炎）症状性发作患者的临床表现、脑电图及影像学特征。方法与结果 回顾分析41 例2019 年3 月至2022 年 3 月在首都医科大学附属北京天坛医院明确诊断为抗LGI1 抗体相关脑炎且有症状性发作患者的临床资料。（1）临床特征：脑炎初期即出现症状性发作，表现形式为癫痫发作［34.15%（14/41）］、面-臂肌张力障碍发作［FBDS，17.07%（7/41）］或二者兼有［48.78%（20/41）］。（2）影像学特征：绝大多数患者表现为典型的单侧或双侧颞叶内侧结构包括杏仁核和海马、海马旁回T₂WI 和FLAIR 成像高信号［87.80%（36/41）］和（或）杏仁核肿胀［65.85%（27/41）］。（3）脑电图特征：发作间期可见脑电背景变慢［53.66%（22/41）］，包括弥漫性、广泛性慢波活动背景［50%（11/22）］，其痫样放电呈单侧（8/14 例）或双侧（6/14 例），亦可呈双侧多灶性，部分患者尚可出现周期性痫样放电［12.20%（5/41）］。视频脑电图记录到症状性发作［78.05%（32/41）］，FBDS 约为59.38%（19/32），其中3 例呈面-臂肌张力障碍发作叠加（FBDS +）；癫痫发作和亚临床发作分别占46.88%（15/32）和12.50%（4/32）。（4）药物治疗：所有患者均于抗癫痫发作药物治疗基础上接受免疫治疗，包括糖皮质激素联合静脉注射免疫球蛋白［IVIg，78.05%（32/41）］、单纯糖皮质激素［12.20%（5/41）］或 IVIg 治疗［9.76%（4/41）］；少数患者同时辅以免疫抑制剂吗替麦考酚酯［14.63%（6/ 41）］。（5）预后：共37 例完成随访，平均随访（21.36 ± 11.53）个月，完全无发作率达86.49%（32/37），停用抗癫痫发作药物比例约为56.76%（21/37）。结论 抗LGI1 抗体相关脑炎症状性发作以颞叶或围外侧裂发作为特点，FBDS 为其最具特征性的临床表现，所有患者均应尽早启动免疫治疗以提高预后良好率。

关键词: 脑炎, 自身免疫性疾病, 癫痫, 脑电描记术, 免疫疗法