Rice Dylan R, Nishiyama Shuhei, Pardo Santiago, Cabal Herrera Ana M, Levy Michael, Mateen Farrah J
Department of Neurology, Massachusetts General Hospital, Boston, MA, United States of America.
Department of Neurology, Massachusetts General Hospital, Boston, MA, United States of America; Department of Neurology, Tohoku University Graduate School of Medicine, Sendai, Japan.
Mult Scler Relat Disord. 2022 Apr;60:103716. doi: 10.1016/j.msard.2022.103716. Epub 2022 Feb 27.
Given the need for specialized laboratory techniques, diagnostic testing for serum antibodies to aquaporin-4, a protein associated with neuromyelitis optica spectrum disorder (NMOSD), is not globally accessible. We aimed to evaluate a novel point-of-care, filter paper-based test for serum AQP4 antibodies (AQP4-Ab).
Adults with AQP4-Ab seropositive NMOSD and seronegative controls (with other central nervous system demyelinating diagnoses) used lancets to place blood drops (∼1 mL) on filter paper cards. Samples were analyzed after an average of 9.4 days using transfected AQP4-GFP HEK293 cells, and results were compared to participants' prior serum AQP4-Ab test results by blinded laboratory staff.
Of 40 participants (mean age 53.7 years; 83% female), 25 were cases and 15 were controls. The most common diagnosis of controls was multiple sclerosis (73%). The average NMOSD disease duration was 6.3 years. All AQP4-Ab seropositive participants were on disease modifying therapies at the time of participation. The point-of-care test yielded a sensitivity of 80% and specificity of 93% (positive and negative predictive values 95% and 74%).
This point-of-care AQP4-Ab testing method may become a pragmatic option to diagnose AQP4-Ab seropositive NMOSD in difficult-to-reach settings. This method should be confirmed with other testing parameters and field tested in new populations.
鉴于对专门实验室技术的需求，针对水通道蛋白4（一种与视神经脊髓炎谱系障碍（NMOSD）相关的蛋白质）血清抗体的诊断检测并非全球都可进行。我们旨在评估一种新型的即时检测、基于滤纸的血清水通道蛋白4抗体（AQP4-Ab）检测方法。
血清AQP4-Ab阳性的NMOSD成年患者和血清阴性对照者（患有其他中枢神经系统脱髓鞘疾病诊断）使用采血针将血滴（约1毫升）滴在滤纸片上。平均9.4天后，使用转染了AQP4-GFP的HEK293细胞对样本进行分析，结果由不知情的实验室工作人员与参与者之前的血清AQP4-Ab检测结果进行比较。
40名参与者（平均年龄53.7岁；83%为女性）中，25例为病例，15例为对照。对照者最常见的诊断是多发性硬化症（73%）。NMOSD的平均病程为6.3年。所有血清AQP4-Ab阳性的参与者在参与研究时都在接受疾病修饰治疗。即时检测的敏感性为80%，特异性为93%（阳性和阴性预测值分别为95%和74%）。
这种即时AQP4-Ab检测方法可能成为在难以到达的地区诊断血清AQP4-Ab阳性NMOSD的实用选择。该方法应通过其他检测参数进行确认，并在新人群中进行现场测试。
