免疫檢查點抑制劑誘發重症肌無力病人的人蒼白桿菌菌血症：案例報告

Ochrobactrum anthropi Bacteremia in a Hepatocellular Carcinoma Patient with Immune Checkpoint Inhibitors Treatment-Induced Myasthenia Gravis

人蒼白桿菌（Ochrobactrum anthropi）是一種見於環境的非發酵革蘭氏陰性桿菌，並不經常造成人類疾病，但是在免疫功能低下或危急狀況的病人則有可能造成伺機性感染。我們報告的案例是一位78歲肝癌病人，接受了免疫檢查點抑制劑療法之後，發生了重症肌無力。隨後重症肌無力並未受到控制，發生了呼吸衰竭與低血壓的危象。此時血液培養報告是O. anthropi。細菌報告顯示此O. anthropi對於大部分常用抗生素是具有抵抗力的，只對少數抗生素如levofloxacin、minocycline及trimethoprim/sulfamethoxazole仍為敏感。在考慮不對重症肌無力產生藥物干擾之下，選擇trimethoprim/sulfamethoxazole做為治療處方，並有良好的臨床反應而成功治療O. anthropi菌血症。

The emergence of Ochrobactrum anthropi as a bloodstream pathogen is uncommon, particularly among critically ill and immunocompromised patients. This case report details a 78-year-old male patient with O. anthropi bacteremia. His medical history was notable for advanced stage non-B non-C hepatocellular carcinoma (HCC), recent treatment with immune checkpoint inhibitors (ICIs), type 2 diabetes mellitus, hypertension, coronary artery disease, and chronic kidney disease. Three weeks before the onset of bacteremia, ICI-induced myasthenia gravis (MG) was diagnosed, which was subsequently managed with pyridostigmine and prednisolone. O. anthropi was identified in two consecutive blood samples. While resistant to most common antibiotics, it remained susceptible to levofloxacin, minocycline, and trimethoprim/sulfamethoxazole (TMP/SMX). Considering the potential exacerbation of MG by certain antibiotics, TMP/SMX was chosen for treatment, and the patient exhibited excellent response.