Department of Pediatrics, Rigshospitalet, University of Copenhagen, Denmark.
Department of Pediatrics, Rigshospitalet, University of Copenhagen, Denmark.
Eur J Paediatr Neurol. 2019 Jul;23(4):639-652. doi: 10.1016/j.ejpn.2019.03.007. Epub 2019 Mar 30.
The incidence of pediatric autoimmune encephalitis (AIE) is unknown. Our aim was to assess the incidence of pediatric AIE in Denmark 2011-17.
In a nationwide population-based setting, we retrieved data on all children tested for AIE before age 18 years. We reviewed medical records in a) children with AIE antibodies (n = 18) to assess whether children fulfilled the AIE consensus criteria, b) children tested negative for AIE antibodies who were registered with an AIE diagnostic code to estimate the incidence of "antibody negative but probable AIE", and c) a reference cohort (n = 596) to determine the positive predictive value of International Classification of Diseases (ICD) codes used for anti-NMDAR encephalitis.
375 children were tested for AIE 2011-17 (median age 11.1 years; 54% girls); 18 children (5%) had AIE antibodies (percentage tested positive): CSF GAD-IgG (3.1%), plasma NMDAR-IgG (2.8%), CSF NMDAR-IgG (1.8%), plasma GAD-IgG (1.0%), and plasma CASPR2-IgG (0.4%). Five children fulfilled the criteria for probably/definite anti-NMDAR encephalitis (incidence: 0.07/100,000 person-years; 95% CI = 0.03-0.17), and 4 children with anti-GAD associated AIE (incidence = 0.055/100,000 person-years, 95% CI = 0.021-0.15). The incidence of "antibody negative but probable AIE" was 0.055/100,000 person-years (95% CI = 0.021-0.15). The positive predictive value of ICD diagnostic codes used for anti-NMDAR encephalitis was 8%.
We diagnosed only children with anti-NMDAR, anti-GAD, and "antibody negative but probable AIE". Before examining AIE antibodies, clinical presentation, paraclinical studies (CSF, EEG, and MRI), and incidence of pediatric AIEs should be considered. Updating the ICD to include AIE codes is warranted.
儿科自身免疫性脑炎（AIE）的发病率尚不清楚。我们的目的是评估丹麦 2011-2017 年儿科 AIE 的发病率。
在全国性的基于人群的设置中，我们检索了所有 18 岁以下接受 AIE 检测的儿童的数据。我们回顾了患有 AIE 抗体的儿童（n=18）的病历，以评估儿童是否符合 AIE 共识标准；回顾了抗体检测阴性但有 AIE 诊断代码的儿童（n=18）的病历，以评估“抗体阴性但可能为 AIE”的发病率；并对参考队列（n=596）进行了回顾，以确定国际疾病分类（ICD）代码用于抗 NMDAR 脑炎的阳性预测值。
2011-2017 年，375 名儿童接受了 AIE 检测（中位年龄 11.1 岁；54%为女孩）；18 名儿童（5%）存在 AIE 抗体（阳性检测百分比）：CSF GAD-IgG（3.1%）、血浆 NMDAR-IgG（2.8%）、CSF NMDAR-IgG（1.8%）、血浆 GAD-IgG（1.0%）和血浆 CASPR2-IgG（0.4%）。5 名儿童符合可能/明确抗 NMDAR 脑炎的标准（发病率：0.07/100,000人年；95%CI=0.03-0.17），4 名儿童存在抗 GAD 相关 AIE（发病率=0.055/100,000 人年，95%CI=0.021-0.15）。“抗体阴性但可能为 AIE”的发病率为 0.055/100,000 人年（95%CI=0.021-0.15）。用于抗 NMDAR 脑炎的 ICD 诊断代码的阳性预测值为 8%。
我们仅诊断了抗 NMDAR、抗 GAD 和“抗体阴性但可能为 AIE”的儿童。在检查 AIE 抗体之前，应考虑临床表型、辅助检查（CSF、EEG 和 MRI）和儿科 AIE 的发病率。值得更新 ICD 以包含 AIE 代码。
