Toplak Natasa, Pimpale Chavan Pallavi, Rosina Silvia, Dallos Tomas, Rotem Semo Oz, Aguiar Cassyanne L, Khubchandani Raju, Ravelli Angelo, Patwardhan Anjali
Department of Allergology, Rheumatology and Clinical Immunology, Faculty of Medicine, University Children's Hospital, University Medical Centre, Ljubljana, Slovenia.
Pediatric Rheumatology, NH SRCC Children's Hospital, Mumbai, India.
Front Pediatr. 2022 Feb 23;9:810785. doi: 10.3389/fped.2021.810785. eCollection 2021.
Juvenile dermatomyositis (JDM) has a wide spectrum of clinical presentations. In the last decade, several myositis-specific antibodies have been identified in patients with JDM and connected with specific organ involvement or specific clinical picture. It has been published that the presence of anti-NXP2 autoantibodies presents a risk for calcinosis in patients with JDM. We aimed to investigate the prevalence of calcinosis and response to the treatment in JDM patients with anti-NXP2. In a retrospective, multinational, multicenter study, data on 26 JDM (19 F, 7 M) patients with positive anti-NXP2 were collected. The mean age at disease presentation was 6.5 years (SD 3.7), the median diagnosis delay was 4 months (range 0.5-27 months). Patients were divided into two groups (A and B) based on the presence of calcinosis, which occurred in 42% of anti-NXP2 positive JDM patients (group A). Four patients already had calcinosis at presentation, one developed calcinosis after 4 months, and 6 developed calcinosis later in the disease course (median 2 years, range 0.8-7.8). The differences in laboratory results were not statistically significant between the groups. The mean age at disease presentation (5.2/7.5 years) trended toward being younger in group A. Children with calcinosis were treated with several combinations of drugs. In four cases, rituximab and, in one case, anti-TNF alpha agents were used successfully. Disease outcome (by evaluation of the treating physician) was excellent in four, good in two, stable in two, and poor in three patients. None of the patients from group B had a poor disease outcome. In conclusion, JDM patients with anti-NXP2 are prone to develop calcinosis, especially if they present with the disease early, before 5 years of age. The development of calcinosis is associated with worse disease outcomes. The combination of several immunomodulatory drugs and biologic drugs can stop calcinosis progression; however, there are no evidence-based therapies for treating calcinosis in JDM patients.
青少年皮肌炎（JDM）有广泛的临床表现。在过去十年中，已在JDM患者中鉴定出几种肌炎特异性抗体，并与特定器官受累或特定临床表现相关。已发表的研究表明，抗NXP2自身抗体的存在会使JDM患者发生钙质沉着症的风险增加。我们旨在调查抗NXP2的JDM患者中钙质沉着症的患病率及治疗反应。在一项回顾性、跨国、多中心研究中，收集了26例抗NXP2阳性的JDM患者（19例女性，7例男性）的数据。疾病初发时的平均年龄为6.5岁（标准差3.7），中位诊断延迟为4个月（范围0.5 - 27个月）。根据钙质沉着症的存在情况，患者被分为两组（A组和B组），钙质沉着症发生在42%的抗NXP2阳性JDM患者中（A组）。4例患者初发时已有钙质沉着症，1例在4个月后出现钙质沉着症，6例在疾病过程后期出现钙质沉着症（中位时间2年，范围0.8 - 7.8年）。两组之间实验室结果的差异无统计学意义。A组疾病初发时的平均年龄（5.2/7.5岁）有趋于更年轻的趋势。有钙质沉着症的儿童接受了多种药物联合治疗。4例患者成功使用了利妥昔单抗，1例患者成功使用了抗TNFα药物。（根据主治医生的评估）疾病转归为4例优秀，2例良好，2例稳定，3例较差。B组患者均无不良疾病转归。总之，抗NXP2的JDM患者易于发生钙质沉着症，尤其是在5岁之前疾病早期发病时。钙质沉着症的发生与更差的疾病转归相关。多种免疫调节药物和生物药物联合可阻止钙质沉着症进展；然而，对于JDM患者钙质沉着症的治疗尚无循证疗法。
