Department of Nuclear Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
State Key Laboratory of Cognitive Neuroscience and Learning & International Data Group/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.
Front Immunol. 2021 Sep 20;12:672846. doi: 10.3389/fimmu.2021.672846. eCollection 2021.
Brain 18F-fluorodeoxyglucose positron emission tomography (FDG PET) is a sensitive technique for assisting in the diagnosis of patients with anti-leucine-rich glioma-inactivated 1 (LGI1) antibody encephalitis. However, the common pattern of this disorder assessed by FDG PET remains unknown. The present study aimed to explore the glucose metabolic patterns of this disorder based on PET voxel analysis.
This retrospective study enrolled 25 patients with anti-LGI1 encephalitis, who were admitted in Beijing Tiantan Hospital between September 2014 and July 2019. The glucose metabolic pattern was compared between the included patients and 44 age- and gender-matched healthy controls using Statistical Parametric Mapping. Then, the correlation between the metabolic pattern and scaled activities of daily living (ADLs) of the patients was assessed.
The median time from symptom onset to PET scans was 9 w (range:2-53w). The groupwise analysis revealed that patients with anti-LGI1 encephalitis had left hippocampal hypermetabolism and hypometabolism in almost all neocortical regions. The individual-level results showed most patients presented a decreased metabolism in neocortical regions, as well as an increase in metabolism in the hippocampus and basal ganglia. Furthermore, the metabolic gradient between hippocampus and neocortical regions was positively associated with the ADLs (frontal lobe, r=0.529, P=0.008; parietal lobe, r=0.474, P=0.019; occipital lobe, r=0.413, P=0.045; temporal lobe, r=0.490, P=0.015), respectively. In addition, the patients with facio-brachial dystonic seizures (FBDS) presented bilateral putamen hypermetabolism, when compared to patients without FBDS and healthy controls.
Subcortical hypermetabolism associated with cortical hypometabolism presented with a common metabolic pattern in patients with anti-LGI1 encephalitis in the present study. The resolution of the metabolic gradient of the hippocampal hypermetabolism and neocortical hypometabolism may bring about improved clinical neurologic disability.
脑 18F-氟代脱氧葡萄糖正电子发射断层扫描（FDG PET）是一种辅助诊断抗亮氨酸丰富胶质瘤失活 1（LGI1）抗体脑炎患者的敏感技术。然而，FDG PET 评估的这种疾病的常见模式尚不清楚。本研究旨在通过 PET 体素分析探讨这种疾病的葡萄糖代谢模式。
本回顾性研究纳入了 2014 年 9 月至 2019 年 7 月在北京天坛医院住院的 25 例抗 LGI1 脑炎患者。使用统计参数映射比较了纳入患者与 44 名年龄和性别匹配的健康对照者的葡萄糖代谢模式。然后，评估了代谢模式与患者日常活动能力（ADL）评分的相关性。
症状出现到 PET 扫描的中位时间为 9 周（范围：2-53 周）。组间分析显示，抗 LGI1 脑炎患者的左侧海马呈代谢亢进，几乎所有新皮质区均呈代谢低下。个体水平结果显示，大多数患者表现为新皮质区代谢降低，而海马和基底节区代谢增加。此外，海马与新皮质区之间的代谢梯度与 ADL 呈正相关（额叶，r=0.529，P=0.008；顶叶，r=0.474，P=0.019；枕叶，r=0.413，P=0.045；颞叶，r=0.490，P=0.015）。此外，与无面臂肌张力障碍发作（FBDS）的患者和健康对照者相比，伴 FBDS 的患者双侧壳核代谢亢进。
本研究中，抗 LGI1 脑炎患者表现出皮质下代谢亢进伴皮质代谢低下的常见代谢模式。海马代谢亢进和新皮质代谢低下的代谢梯度缓解可能会带来临床神经功能残疾的改善。
