Expert Perspective: Immune Checkpoint Inhibitors and Rheumatologic Complications.

Rheumatologists increasingly receive consults for patients treated with immune checkpoint inhibitors (ICIs) for cancer. ICIs can cause inflammatory syndromes known as immune-related adverse events (irAEs). Several rheumatologic irAEs are reported including inflammatory arthritis, polymyalgia rheumatica, and myositis. For patients who present with musculoskeletal symptoms while on ICI therapy, it is important to have an algorithm for evaluation. The differential diagnosis includes a range of musculoskeletal syndromes like crystalline arthritis, mechanical issues, and osteoarthritis, in addition to irAEs. After diagnosing a rheumatologic irAE, rheumatologists must work with the patient and their oncologist to form a treatment plan. Treatment of irAEs is guided by severity. Evidence for management is limited to observational studies. Inflammatory arthritis and polymyalgia rheumatica are treated with non-steroidal anti-inflammatory drugs in mild cases, corticosteroids for moderate to severe cases, and sometimes require other disease modifying anti-rheumatic drugs. Myositis due to ICIs can be accompanied by myocarditis or myasthenia gravis. Corticosteroids and holding the ICI are usually required to treat myositis; some patients with severe myositis need intravenous immunoglobulin or plasmapheresis. Further research is needed to optimize treatment of irAEs that does not compromise the anti-tumor effect of ICIs.

风湿病学家越来越多地接到接受免疫检查点抑制剂（ICIs）治疗癌症的患者的会诊请求。ICIs可导致被称为免疫相关不良事件（irAEs）的炎症综合征。据报道，有几种风湿性irAEs，包括炎性关节炎、风湿性多肌痛和肌炎。对于在接受ICI治疗期间出现肌肉骨骼症状的患者，制定一个评估算法很重要。鉴别诊断包括一系列肌肉骨骼综合征，除了irAEs外，还包括晶体性关节炎、机械性问题和骨关节炎。在诊断出风湿性irAE后，风湿病学家必须与患者及其肿瘤学家合作制定治疗方案。irAEs的治疗以严重程度为指导。管理的证据仅限于观察性研究。在轻度病例中，炎性关节炎和风湿性多肌痛用非甾体抗炎药治疗，中重度病例用糖皮质激素治疗，有时还需要其他改善病情的抗风湿药。由ICIs引起的肌炎可伴有心肌炎或重症肌无力。通常需要糖皮质激素并停用ICI来治疗肌炎；一些患有严重肌炎的患者需要静脉注射免疫球蛋白或血浆置换。需要进一步研究以优化irAEs的治疗，同时不影响ICIs的抗肿瘤效果。