Abstract：
Immune checkpoint inhibitors (ICIs) sometimes induce immune-related adverse events (irAEs), and arthritis is one of the irAE symptoms. Recently, crystal-induced arthritis, such as calcium pyrophosphate (CPP) crystal deposition disease and gout, has been reported to occur after ICI administration. However, the distinction between ICI-associated crystal arthritis and ICI-induced non-crystal arthritis is difficult because their symptoms are similar. Besides, optimal treatment for ICI-associated crystal arthritis has not been established. Here, we report a patient who developed CPP crystal arthritis twice after pembrolizumab (ICI) administration and was successfully treated with intra-articular glucocorticoid injection. He suffered arthritis and acute interstitial nephritis simultaneously after ICI administration. Musculoskeletal ultrasound of his affected joint suggests that his arthritis was crystal-induced arthritis, and arthrocentesis detected CPP crystal in synovial fluid. Thus, we diagnosed his arthritis as ICI-associated cystal arthritis. Therefore, our case encourages the use of musculoskeletal ultrasound in patients with arthritis after treatment with ICI because it may distinguish between ICI-associated crystal arthritis and ICI-induced non-crystal arthritis. Besides, ICI-associated crystal arthritis could be treatable by intra-articular glucocorticoid injection.
摘要：
免疫检查点抑制剂（ICIs）有时会诱发免疫相关不良事件（irAE），关节炎是irAE的症状之一。最近,晶体诱发的关节炎，如焦磷酸钙（CPP）晶体沉积病和痛风，据报道，ICI给药后发生。然而,ICI相关性晶体性关节炎和ICI诱导的非晶体性关节炎难以区分,因为它们的症状相似.此外,ICI相关性晶体关节炎的最佳治疗方法尚未确定.这里,我们报道了1例患者,该患者在pembrolizumab(ICI)给药后2次出现CPP晶体关节炎,并通过关节内糖皮质激素注射成功治疗.ICI给药后，他同时患有关节炎和急性间质性肾炎。受累关节的肌肉骨骼超声检查表明他的关节炎是晶体诱发的关节炎，关节穿刺术在滑液中检测到CPP晶体。因此，我们诊断他的关节炎为ICI相关的膀胱关节炎.因此,我们的病例鼓励在ICI治疗后的关节炎患者中使用肌肉骨骼超声,因为它可以区分ICI相关的晶体关节炎和ICI诱导的非晶体关节炎.此外,ICI相关的晶体关节炎可以通过关节内糖皮质激素注射来治疗。
