Department of Neurology, Baylor College of Medicine, Houston, Texas, USA.
Centro Nacional de Esclerosis Multiple, Asuncion, Paraguay.
Mult Scler Relat Disord. 2021 Aug;53:103083. doi: 10.1016/j.msard.2021.103083. Epub 2021 Jun 15.
Neuromyelitis optica spectrum disorders (NMOSD) is an increasing diagnostic and therapeutic challenge in Latin America (LATAM). Despite the heterogeneity of this population, ethnic and socioeconomic commonalities exist, and epidemiologic studies from the region have had a limited geographic and population outreach. Identification of some aspects from the entire region are lacking.
To determine ethnic, clinical characteristics, and utilization of diagnostic tools and types of therapy for patients with NMOSD in the entire Latin American region.
The Latin American Committee for Treatment and Research in MS (LACTRIMS) created an exploratory investigational survey addressed by Invitation to NMOSD Latin American experts identified through diverse sources. Data input closed after 30 days from the initial invitation. The questionnaire allowed use of absolute numbers or percentages. Multiple option responses covering 25 themes included definition of type of practice; number of NMOSD cases; ethnicity; utilization of the 2015 International Panel criteria for the diagnosis of Neuromyelitis optica (IPDN); clinical phenotypes; methodology utilized for determination of anti-Aquaporin-4 (anti- AQP4) antibodies serological testing, and if this was performed locally or processed abroad; treatment of relapses, and long-term management were surveyed.
We identified 62 investigators from 21 countries reporting information from 2154 patients (utilizing the IPDN criteria in 93.9% of cases), which were categorized in two geographical regions: North-Central, including the Caribbean (NCC), and South America (SA). Ethnic identification disclosed Mestizos 61.4% as the main group. The most common presenting symptoms were concomitant presence of optic neuritis and transverse myelitis in 31.8% (p=0.95); only optic neuritis in 31.4% (more common in SA), p<0.001); involvement of the area postrema occurred in 21.5% and brain stem in 8.3%, both were more frequent in the South American cases (p<0.001). Anti-AQP4 antibodies were positive in 63.9% and anti-Myelin Oligodendrocyte Glycoprotein (MOG) antibodies in 4.8% of total cases. The specific laboratorial method employed was not known by 23.8% of the investigators. Acute relapses were identified in 81.6% of cases, and were treated in 93.9% of them with intravenous steroids (IVS); 62.1% with plasma exchange (PE), and 40.9% with intravenous immunoglobulin-G (IVIG). Therapy was escalated in some cases due to suboptimal initial response. Respondents favored Rituximab as long-term therapy (86.3%), whereas azathioprine was also utilized on 81.8% of the cases, either agent used indistinctly by the investigators according to treatment accessibility or clinical judgement. There were no differences among the geographic regions.
This is the first study including all countries of LATAM and the largest cohort reported from a multinational specific world area. Ethnic distributions and phenotypic features of the disease in the region, challenges in access to diagnostic tools and therapy were identified. The Latin American neurological community should play a determinant role encouraging and advising local institutions and health officials in the availability of more sensitive and modern diagnostic methodology, in facilitating the the access to licensed medications for NMOSD, and addressing concerns on education, diagnosis and management of the disease in the community.
视神经脊髓炎谱系疾病（NMOSD）在拉丁美洲（LATAM）是一个日益严峻的诊断和治疗挑战。尽管该人群存在异质性，但存在着种族和社会经济的共同性，而且该地区的流行病学研究的地理和人口覆盖面有限。缺乏对整个地区某些方面的了解。
确定拉丁美洲整个地区 NMOSD 患者的种族、临床特征以及诊断工具的使用情况和治疗类型。
拉丁美洲多发性硬化治疗和研究委员会（LACTRIMS）创建了一个探索性调查，通过多种来源确定的 NMOSD 拉丁美洲专家邀请进行。从最初邀请开始后的 30 天内关闭数据输入。问卷允许使用绝对数字或百分比。涵盖 25 个主题的多项选择回答包括实践类型的定义；NMOSD 病例数；种族；2015 年国际视神经脊髓炎专家组诊断标准（IPDN）的使用情况；临床表型；用于确定抗水通道蛋白-4（抗-AQP4）抗体血清学检测的方法，如果是在本地进行还是在国外进行；复发病例的治疗和长期管理情况进行了调查。
我们确定了来自 21 个国家的 62 名研究人员，报告了来自 2154 名患者的信息（93.9%的病例采用了 IPDN 标准），这些患者分为两个地理区域：中北部，包括加勒比地区（NCC）和南美洲（SA）。种族鉴定显示梅斯蒂索人是主要群体，占 61.4%。最常见的首发症状是视神经炎和横贯性脊髓炎同时存在，占 31.8%（p=0.95）；视神经炎单独出现，占 31.4%（在南美洲更常见），p<0.001）；后极区受累发生率为 21.5%，脑干受累发生率为 8.3%，两者在南美洲病例中更为常见（p<0.001）。抗-AQP4 抗体阳性率为 63.9%，抗髓鞘少突胶质细胞糖蛋白（MOG）抗体阳性率为 4.8%。23.8%的研究人员不知道具体使用的实验室方法。81.6%的病例出现急性复发，93.9%的病例接受了静脉内类固醇（IVS）治疗；62.1%接受了血浆置换（PE），40.9%接受了静脉注射免疫球蛋白-G（IVIG）。由于初始反应不理想，一些病例需要升级治疗。受访者赞成利妥昔单抗作为长期治疗（86.3%），而 81.8%的病例也使用了硫唑嘌呤，研究人员根据治疗的可及性或临床判断，分别使用这两种药物。在地理区域之间没有差异。
这是第一项包括 LATAM 所有国家和报告的来自特定世界地区的最大队列的研究。确定了该地区疾病的种族分布和表型特征、诊断工具和治疗方法的获取方面的挑战。拉丁美洲神经科社区应发挥决定性作用，鼓励和建议当地机构和卫生官员提供更敏感和现代的诊断方法，促进 NMOSD 许可药物的获取，并解决社区对疾病的教育、诊断和管理方面的问题。
