Reference Center for Neuromuscular Diseases, FILNEMUS, Paris, France.
INSERM U955-Team 10, Department of Neurosciences, Mondor Biomedical Research Institute, Paris-Est University, Créteil, France.
Rheumatology (Oxford). 2018 May 1;57(5):873-879. doi: 10.1093/rheumatology/kex516.
Myositis-specific autoantibodies (MSAs) are increasingly used to delineate distinct subgroups of JDM. The aim of our study was to explore without a priori hypotheses whether MSAs are associated with distinct clinical-pathological changes and severity in a monocentric JDM cohort.
Clinical, biological and histological findings from 23 JDM patients were assessed. Twenty-six histopathological parameters were subjected to multivariate analysis.
Autoantibodies included anti-NXP2 (9/23), anti-TIF1γ (4/23), anti-MDA5 (2/23), no MSAs (8/23). Multivariate analysis yielded two histopathological clusters. Cluster 1 (n = 11) showed a more severe and ischaemic pattern than cluster 2 (n = 12) assessed by: total score severity ⩾ 20 (100.0% vs 25.0%); visual analogic score ⩾6 (100.0% vs 25.0%); the vascular domain score >1 (100.0% vs 41.7%); microinfarcts (100% vs 58.3%); ischaemic myofibrillary loss (focal punched-out vacuoles) (90.9 vs 25%); and obvious capillary loss (81.8% vs 16.7). Compared with cluster 2, patients in cluster 1 had strikingly more often anti-NXP2 antibodies (7/11 vs 2/12), more pronounced muscle weakness, more gastrointestinal involvement and required more aggressive treatment. Furthermore, patients with anti-NXP2 antibodies, mostly assigned in the first cluster, also displayed more severe muscular disease, requiring more aggressive treatment and having a lower remission rate during the follow-up period.
Marked muscle ischaemic involvement and the presence of anti-NXP2 autoantibodies are associated with more severe forms of JDM.
肌炎特异性自身抗体（MSAs）越来越多地用于划定 JDM 的不同亚组。我们的研究目的是在单中心 JDM 队列中探索有无先验假设，MSAs 是否与不同的临床病理变化和严重程度相关。
评估了 23 例 JDM 患者的临床、生物学和组织学发现。对 26 个组织病理学参数进行了多变量分析。
自身抗体包括抗 NXP2（9/23）、抗 TIF1γ（4/23）、抗 MDA5（2/23）、无 MSAs（8/23）。多变量分析产生了两个组织病理学簇。簇 1（n=11）比簇 2（n=12）表现出更严重和缺血性的模式，评估如下：总严重程度评分 ⩾20（100.0%比 25.0%）；视觉模拟评分 ⩾6（100.0%比 25.0%）；血管域评分 ⩾1（100.0%比 41.7%）；微梗死（100%比 58.3%）；缺血性肌纤维丧失（局灶性打孔样空泡）（90.9%比 25%）；和明显的毛细血管丧失（81.8%比 16.7%）。与簇 2 相比，簇 1 中的患者更频繁地出现抗 NXP2 抗体（7/11 比 2/12），肌肉无力更明显，胃肠道受累更多，需要更积极的治疗。此外，主要归入第一簇的抗 NXP2 抗体患者也表现出更严重的肌肉疾病，需要更积极的治疗，在随访期间缓解率较低。
明显的肌肉缺血性受累和抗 NXP2 自身抗体的存在与更严重的 JDM 形式相关。
