Department of Neurology, Dokkyo Medical University, Tochigi, Japan.
BMC Neurol. 2022 Apr 21;22(1):148. doi: 10.1186/s12883-022-02674-6.
Patients with antibodies against leucine-rich glioma-inactivated 1 (LGI1) present with limbic encephalitis, which is clinically characterized by a subacute disturbance of memory and behavior, often experience seizures. Most patients have a monophasic course, often with hyponatremia.
Herein, we report a 67-year-old Japanese male presenting with involuntary neck movement, abnormal behavior and apraxia. He was disoriented to time and place and occasionally unable to follow directions. Laboratory tests revealed the patient had hyponatremia (131 mEq/L). Cerebrospinal fluid (CSF) analysis showed that the cell count (1/μL) and protein content (33 mg/dL) were in the normal ranges. Electroencephalography showed transient theta bursts in the right frontal lobe. Magnetic resonance imaging (MRI) of the brain demonstrated hyperintensities in the medial temporal lobe and basal forebrain on fluid-attenuated inversion recovery (FLAIR) without gadolinium enhancement. Anti-voltage-gated potassium channel (Anti-VGKC) complex antibodies were below the reference level for limbic encephalitis. Although the diagnosis was unknown, intravenous methylprednisolone therapy was effective. Three years later, the patient began to speak incoherently and became disoriented to time. FLAIR MRI of the brain revealed recurrence in the left medial temporal lobe. The patient's serum sodium level was 131 mEq/L. After intravenous methylprednisolone therapy, he regained alertness. A CSF sample stored at the time of the first attack was assayed and the patient was found to be LGI1-positive and CASPR-2-negative, and the diagnosis of anti-LGI1 encephalitis was made.
Monitoring serum sodium levels and the preserved samples from the first episode were useful for diagnosis.
抗亮氨酸丰富的胶质瘤失活 1 抗体（LGI1）阳性的患者表现为边缘性脑炎，其临床特征为亚急性记忆和行为障碍，常伴有癫痫发作。大多数患者呈单相病程，常伴有低钠血症。
本研究报告了一位 67 岁的日本男性，表现为不自主的颈部运动、行为异常和失用症。他对时间和地点感到迷失方向，偶尔无法听从指示。实验室检查发现患者有低钠血症（131 mEq/L）。脑脊液（CSF）分析显示细胞计数（1/μL）和蛋白含量（33 mg/dL）在正常范围内。脑电图显示右额叶有短暂的θ爆发。脑部磁共振成像（MRI）显示液体衰减反转恢复（FLAIR）上内侧颞叶和基底前脑高信号，无钆增强。抗电压门控钾通道（Anti-VGKC）复合物抗体低于边缘性脑炎的参考水平。尽管诊断不明，但静脉注射甲基强的松龙治疗有效。3 年后，患者开始语无伦次，对时间感到迷失方向。脑部 FLAIR MRI 显示左侧内侧颞叶复发。患者血清钠水平为 131 mEq/L。静脉注射甲基强的松龙治疗后，他恢复了警觉。检测了首次发病时储存的脑脊液样本，发现患者 LGI1 阳性，CASPR-2 阴性，诊断为抗 LGI1 脑炎。
监测血清钠水平和保存的首发样本对诊断很有帮助。
