Rheumatology, University Hospital of Lausanne and Lausanne University, Avenue Pierre-Decker 4, 1005, Lausanne, Switzerland.
Institute of Microbiology, University Hospital of Lausanne and Lausanne University, Lausanne, Switzerland.
J Med Case Rep. 2022 Feb 21;16(1):75. doi: 10.1186/s13256-022-03278-x.
Mycobacterium malmoense is a species of slow-growing nontuberculous mycobacteria. It causes mostly pulmonary infections or lymphadenitis in children, but is increasingly encountered in isolated tenosynovitis in adults. Diagnosis is often delayed because of the rarity of the condition and the difficulty of culturing the bacteria.
We report on a rare association of seronegative polyarthritis with infectious nontuberculous mycobacteria tenosynovitis. A 65-year-old Caucasian female was referred to our clinic because of persisting tenosynovitis of the finger flexor tendons of her right hand, despite two previous synovectomies. She also reported bilateral shoulder and left wrist pain. Paraclinical investigations showed slightly elevated inflammatory parameters. Ultrasound showed synovitis of metacarpophalangeal joints of the right hand and right knee, and a bilateral subacromial bursitis. Hand magnetic resonance imaging also revealed an erosive carpal synovitis. Bacteriological analysis of the second tenosynovectomy specimen showed no growths in aerobic and anaerobic cultures. An additional synovial fluid analysis of the wrist joint was negative for mycobacteria and crystals. Seronegative polyarthritis was suspected, but the initiated immunosuppressive treatment with prednisolone and methotrexate resulted in no clinical improvement of the tenosynovitis. Yet the other joints responded well, and the inflammatory parameters normalized. The immunosuppression was later stopped because of side effects. Due to massive worsening of the tenosynovitis, a third synovectomy was performed. Mycobacterium malmoense was identified on biopsy, leading to the diagnosis of infectious tenosynovitis. At this point, we started an antituberculous therapy, with incomplete response. A combination of antimicrobial and immunosuppressive treatment finally led to the desired clinical improvement.
The treatment of nontuberculous mycobacteria tenosynovitis is not well established, but combining antibiotics with surgical debridement is probably the most adequate approach. Our case highlights the importance of having a high clinical suspicion of an atypical infection in patients with inflammatory tenosynovitis not responding to usual care.
马尔默分枝杆菌是一种生长缓慢的非结核分枝杆菌。它主要引起儿童肺部感染或淋巴结炎，但在成人孤立性腱鞘炎中越来越常见。由于这种疾病罕见且细菌培养困难，因此诊断常常被延误。
我们报告了一例罕见的血清阴性多关节炎与感染性非结核分枝杆菌腱鞘炎的关联。一名 65 岁的白人女性因右手屈肌腱腱鞘炎持续存在而被转诊至我们诊所，尽管之前已经进行了两次滑膜切除术。她还报告双侧肩部和左侧腕部疼痛。临床检查显示炎症参数略有升高。超声显示右手和右膝的掌指关节滑膜炎，以及双侧肩峰下滑囊炎。手部磁共振成像还显示腕关节侵蚀性腕滑膜关节炎。第二次滑膜切除术标本的细菌学分析显示，需氧和厌氧培养均无生长。对腕关节滑液的进一步分析也未发现分枝杆菌和晶体。怀疑为血清阴性多关节炎，但开始的泼尼松龙和甲氨蝶呤免疫抑制治疗并没有改善腱鞘炎的临床症状。然而，其他关节反应良好，炎症参数恢复正常。由于副作用，后来停止了免疫抑制治疗。由于腱鞘炎大量恶化，进行了第三次滑膜切除术。活检发现马尔默分枝杆菌，导致感染性腱鞘炎的诊断。此时，我们开始进行抗结核治疗，但反应不完全。最终，抗菌药物和免疫抑制剂联合治疗达到了预期的临床改善。
非结核分枝杆菌腱鞘炎的治疗方法尚未确立，但抗生素联合手术清创可能是最适当的方法。我们的病例强调了在常规治疗无效的炎症性腱鞘炎患者中，对非典型感染保持高度临床怀疑的重要性。
