Objectives A new form of systemic juvenile idiopathic arthritis (SJIA) with associated lung disease (SJIA-LD) has recently been described. Multiple lines of treatment have failed to yield satisfactory results for this disorder. JAK inhibitors (JAKis) have recently been approved for the treatment of JIA, but clinical evidence of their efficacy in SJIA-LD is still weak. Here we describe and assess real-life experience of SJIA-LD treatment with JAKis in France. Methods This is a retrospective study based on information gathered from patients’ medical records. Systemic and pulmonary symptoms, biological data including CRP, ferritin, IL18, chest CT scan, and functional respiratory tests were collected. Results Eight patients with SJIA-LD were identified in French pediatric rheumatology centers. All received at least one JAKi (baricitinib, ruxolitinib, and/or tofacitinib). Complete disease control was obtained in four patients. Steroids were tapered in four patients and stopped in two. Three patients presented an episode of MAS shortly after anti-IL1s were stopped when JAKis were introduced. Two patients had other serious side effects (viral reactivation—EBV, BK virus, cytopenia). At last follow-up, one patient had died from severe MAS, two patients had undergone hematopoietic stem cell transplantation, four were in complete response (two of them free of steroids), and one in partial response with JAKis. Lung response to JAKi was not clearly linked to disease duration. Conclusion JAKis offer another therapeutic option for patients with SJIA-LD. However, the risk of MAS argues for caution about stopping anti-IL1s when introducing JAKis. Tolerance needs careful monitoring in larger studies.

中文翻译：

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JAK 抑制剂在全身性幼年特发性关节炎伴肺病 （SJIA-LD） 中的作用：法国经验


目的 最近描述了一种新型的系统性幼年特发性关节炎 （SJIA） 伴相关肺病 （SJIA-LD）。多种治疗未能为这种疾病产生令人满意的结果。JAK 抑制剂 （JAKis） 最近被批准用于治疗 JIA，但其对 SJIA-LD 疗效的临床证据仍然较弱。在这里，我们描述和评估了法国使用 JAKis 治疗 SJIA-LD 的真实经验。方法 这是一项基于从患者病历中收集的信息的回顾性研究。收集全身和肺部症状、生物资料，包括 CRP 、 铁蛋白 、 IL18 、 胸部 CT 扫描和功能呼吸测试。结果 8 例 SJIA-LD 患者在法国儿科风湿病中心被发现。所有患者都接受了至少一种 JAKi（巴瑞克替尼、鲁索替尼和/或托法替尼）。4 例患者获得完全疾病控制。4 例患者逐渐减少类固醇治疗，2 例患者停用类固醇。3 例患者在引入 JAKis 时停用抗 IL1 后不久出现 MAS 发作。2 例患者有其他严重的副作用 （病毒再激活 — EBV、BK 病毒、血细胞减少）。在最后一次随访中，1 例患者死于重度 MAS，2 例接受了造血干细胞移植，4 例完全缓解 （其中 2 例未使用类固醇），1 例对 JAKis 部分缓解。肺部对 JAKi 的反应与病程没有明确关联。结论 JAKis 为 SJIA-LD 患者提供了另一种治疗选择。然而，MAS 的风险表明，在引入 JAKis 时应谨慎停用抗 IL1。在更大规模的研究中，需要仔细监测耐受性。