中国東北部における抗γ-アミノ酪酸-B（GABA-B）受容体脳炎の臨床的特徴と予後解析

Clinical characteristics and prognostic analysis of anti-gamma-aminobutyric acid-B (GABA-B) receptor encephalitis in Northeast China.

• Xinyue Zhang
• Yue Lang
• Lichao Sun
• Weiguanliu Zhang
• Weihong Lin
• Li Cui

抄録

目的:

抗γ-アミノ酪酸-B（GABA-B）受容体脳炎の臨床的特徴と予後を調べる。

OBJECTIVE: To investigate the clinical characteristics and prognosis of anti-gamma-aminobutyric acid-B (GABA-B) receptor encephalitis.

方法:

このレトロスペクティブ研究では、抗GABA-B受容体脳炎患者19例を登録した。臨床症状、放射線学的および脳波学的特徴、治療および転帰を収集し、分析した。神経学的機能は修正Rankin Scale（mRS）に従って評価した。

METHODS: This retrospective study enrolled nineteen patients with anti-GABA-B receptor encephalitis. Clinical manifestations, radiological and electroencephalogram features, treatment and outcomes were collected and analyzed. The neurological function was evaluated according to the modified Rankin Scale (mRS).

結果:

好予後群（mRS≤2）は11例，不良予後群（mRS>2）は8例であった．好予後群では、臨床症状として記憶障害（n=10、90.9％）、てんかん発作（n=9、81.8％）、精神障害（n=9、81.8％）、意識障害（n=5、45.5％）が認められ、MRIでは大脳辺縁系の病変が3例（27.3％）に認められた。肺がんが1例（9.1％）に認められた。平均11.7ヵ月の経過観察期間で4例（36.4％）が治癒し、7例（63.6％）に有意な改善が認められた。低悪性度群では全例に記憶障害、てんかん発作、精神障害、意識障害を認め、5例（62.5％）にてんかん痙攣状態、5例（62.5％）に呼吸不全を認め、MRIでは7例（87.5％）に大脳辺縁系の病変が認められた。5例（62.5％）で悪性腫瘍が検出された。平均14.8ヵ月の追跡調査期間の後、7例（87.5％）が死亡し、1例（12.5％）が日常生活に依存したままであった。

RESULTS: There were eleven patients in the favorable-prognosis group (mRS ≤ 2) and eight patients in the poor-prognosis group (mRS > 2). In the favorable-prognosis group, clinical symptoms included memory deterioration (n = 10; 90.9%), epileptic seizures (n = 9; 81.8%), psychiatric disorders (n = 9; 81.8%), and conscious disturbance (n = 5; 45.5%); magnetic resonance imaging (MRI) indicated an involvement of the limbic system in three (27.3%) cases in this group. Lung cancer was detected in one patient (9.1%). After an average follow-up period of 11.7 months, four (36.4%) patients were cured, and seven (63.6%) patients showed significant improvements. In the poor-prognosis group, all patients presented with memory deterioration, epileptic seizures, psychiatric disorders, and conscious disturbance; five (62.5%) patients had convulsive status epilepticus, and five (62.5%) patients developed respiratory failure; MRI indicated an involvement of the limbic system in seven (87.5%) cases. Malignant tumors were detected in five (62.5%) patients. After an average follow-up period of 14.8 months, seven (87.5%) patients died and one (12.5%) patient remained dependent in daily life.

結論:

抗GABA-B受容体脳炎の臨床症状には、てんかん発作、認知障害および精神障害が含まれる。痙攣性てんかん状態または呼吸不全の患者は予後が悪い。抗GABA-B受容体脳炎では、大脳辺縁系の病変は予後不良と関連しており、放射線検査は疾患の進行を反映している可能性がある。早期診断と適切な治療が強調されるべきである。

CONCLUSIONS: The clinical manifestations of anti-GABA-B receptor encephalitis include epileptic seizures, cognitive impairment and psychiatric disorders. Patients with convulsive status epilepticus or respiratory failure have poor outcomes. In anti-GABA-B receptor encephalitis, limbic system involvement is associated with a poor prognosis in and radiological examinations can reflect disease progression. Early diagnosis and appropriate treatment should be highlighted.