Department of Physiology, University of Colombo, Colombo, Sri Lanka.
Department of Immunology, Medical Research Institute, Colombo, Sri Lanka.
BMC Neurol. 2021 May 19;21(1):203. doi: 10.1186/s12883-021-02232-6.
Autoimmune encephalitis (AE) is now considered a main, potentially curable cause of encephalitis, but remains conspicuously underreported from South Asia. We studied the clinical characteristics in relation to their antibody status and outcomes of patients presenting with AE in Sri Lanka.
Patients admitting to government hospitals who were clinically suspected of AE by an on-site neurologist were prospectively recruited over a period of 12 months. Sera and cerebrospinal fluid were tested for NMDAR, AMPAR1, AMPAR2, LGI1, CASPR2, GABARB1/B2 antibodies (Ab) using commercial cell-based assays. Demographic, clinical and laboratory data were compiled into an investigator-administered proforma. Patients were reviewed at 1 year follow up either in person or via telephone.
One-hundred and forty-two patients from 21 of 25 districts in Sri Lanka (median age = 20.5 years; range 1-86 years; females = 61.3%) were recruited. Of them, 65 (45.8%; median age = 19 years; range 1-86 years; females = 64.6%) fulfilled diagnostic criteria for probable NMDAR-antibody encephalitis (NMDARE) and 6 (4.2%; median age = 44 years; range 28-71 years; females = 83.3%) limbic encephalitis (LE). Abnormal behaviour (95.3%), seizures (81.5%) and movement disorders (69.2%) were the most frequent clinical manifestations of probable NMDARE. NMDAR-antibodies were detectable in 29 (44.6%) and not detectable in 36 in CSF of probable-NMDARE patients. Abnormal EEG was more frequent (p = 0.003) while a worse outcome (OR = 2.78; 95% CI = 0.88-9.09) and deaths (OR = 2.38; 95% CI = 0.67-8.33) were more likely in antibody-negative than antibody-positive probable-NMDARE. Most patients with LE had amnesia (50%) and/or confusion (100%) with agitation (83.3%) and seizures (100%) but none had detectable antibodies to any of the antigens tested.
NMDARE is the commonest type of AE among South Asians as is the case worldwide. Clinical presentations of NMDARAb-positive and NMDARAb-negative AE patients do not significantly differ but EEG may be a useful marker of an autoimmune basis for psychiatric symptoms.
自身免疫性脑炎（AE）现在被认为是脑炎的主要潜在可治愈原因，但在南亚地区却明显报告不足。我们研究了与抗体状态相关的临床特征以及在斯里兰卡就诊的 AE 患者的结局。
在 12 个月的时间里，由现场神经科医生临床疑似 AE 的患者被前瞻性招募到政府医院。使用商业细胞基检测试剂盒检测血清和脑脊液中的 NMDAR、AMPA R1、AMPA R2、LGI1、CASPR2、GABARB1/B2 抗体（Ab）。将人口统计学、临床和实验室数据汇编到研究者管理的表格中。在 1 年的随访中，通过亲自或电话对患者进行评估。
从斯里兰卡 25 个区中的 21 个区（中位年龄 20.5 岁；范围 1-86 岁；女性 61.3%）招募了 142 名患者。其中，65 名（45.8%；中位年龄 19 岁；范围 1-86 岁；女性 64.6%）符合 NMDA 受体抗体脑炎（NMDARE）的可能诊断标准，6 名（4.2%；中位年龄 44 岁；范围 28-71 岁；女性 83.3%）符合边缘性脑炎（LE）。异常行为（95.3%）、癫痫发作（81.5%）和运动障碍（69.2%）是可能 NMDARE 最常见的临床表现。29 例患者的脑脊液中可检测到 NMDAR 抗体（44.6%），36 例患者的脑脊液中未检测到 NMDAR 抗体。异常脑电图更为常见（p=0.003），而抗体阴性患者的结局更差（OR=2.78；95%CI=0.88-9.09）和死亡率更高（OR=2.38；95%CI=0.67-8.33）。大多数 LE 患者有健忘症（50%）和/或意识混乱（100%），伴有激越（83.3%）和癫痫发作（100%），但无一例患者可检测到任何已测试抗原的抗体。
NMDARE 是南亚地区与全球范围内最常见的 AE 类型。NMDARAb 阳性和 NMDARAb 阴性 AE 患者的临床表现无显著差异，但脑电图可能是精神症状自身免疫基础的有用标志物。
