Ichihara Asako, Jinnin Masatoshi, Fukushima Satoshi, Inoue Yuji, Ihn Hironobu
Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
J Dermatol. 2014 May;41(5):414-7. doi: 10.1111/1346-8138.12459.
Mycobacterium chelonae is a non-tuberculous, rapidly growing mycobacteria and is widely distributed in the natural environment. In the immunocompetent status, localized cutaneous infections such as cellulitis and subcutaneous abscesses commonly occur after traumatic injury. However, disseminated cutaneous infections occur on a background of immunosuppression. Cutaneous M. chelonae infection presents with a variety of skin eruptions. We report a case of disseminated M. chelonae infection mimicking cutaneous vasculitis. The patient was treated with long-term oral corticosteroids and injected etanercept for the treatment of rheumatoid arthritis and asthma. Because the skin eruptions were preceded by asthma and rheumatoid arthritis and the pathological findings showed fibrinoid necrosis around the vascular of dermis, cutaneous vasculitis was first suspected. The culture from the pus revealed the bacterium which grew within 5 days on Ogawa's culture medium suggesting a rapidly growing mycobacteria. This bacterium was identified as M. chelonae by the DNA-DNA hybridization method. We chose 800 mg/day clarithromycin and 500 mg/day levofloxacin as a result of the drug-sensitivity test. After 6 months of the treatment, infection symptoms disappeared. Rapidly growing mycobacteria should be considered in the differential diagnosis of infections in patients under immunosuppression caused by diseases or drugs such as corticosteroids and biologic agents. Repeated bacterial examinations are important and required for the diagnosis of rapidly growing mycobacteria.
龟分枝杆菌是一种非结核性、快速生长的分枝杆菌，广泛分布于自然环境中。在免疫功能正常的情况下，创伤后常发生局部皮肤感染，如蜂窝织炎和皮下脓肿。然而，播散性皮肤感染则发生在免疫抑制的背景下。皮肤龟分枝杆菌感染表现为多种皮肤疹。我们报告一例疑似皮肤血管炎的播散性龟分枝杆菌感染病例。该患者长期口服皮质类固醇并注射依那西普治疗类风湿性关节炎和哮喘。由于皮疹先于哮喘和类风湿性关节炎出现，且病理结果显示真皮血管周围有纤维蛋白样坏死，最初怀疑为皮肤血管炎。脓液培养显示该细菌在小川培养基上5天内生长，提示为快速生长的分枝杆菌。通过DNA-DNA杂交法将该细菌鉴定为龟分枝杆菌。根据药敏试验结果，我们选择了800毫克/天的克拉霉素和500毫克/天的左氧氟沙星。治疗6个月后，感染症状消失。在由疾病或药物（如皮质类固醇和生物制剂）引起的免疫抑制患者的感染鉴别诊断中，应考虑快速生长的分枝杆菌。反复进行细菌检查对快速生长分枝杆菌的诊断很重要且必要。
