アエロコッカス・ウリナエによる僧帽弁感染性心内膜炎および脳への多発性塞栓症の稀な症例

Aerococcus urinae is a rarely encountered Gram-positive bacterium that primarily causes urinary tract infections (UTIs), but in rare cases, it can result in bloodstream infections such as bacteremia, infective endocarditis (IE), and septic embolization. Despite its low virulence, A. urinae endocarditis carries high morbidity and mortality due to diagnostic challenges and delayed recognition. We report a case of A. urinae IE involving the native mitral valve, complicated by severe mitral regurgitation and multiple cerebral septic emboli. The patient's course was marked by rapid clinical deterioration despite prompt initiation of guideline-directed antimicrobial therapy and multidisciplinary management involving cardiology, infectious disease (ID), intensive care, and cardiothoracic surgery teams. This case contributes to the growing body of literature recognizing A. urinae as a possible etiologic agent in elderly patients with urinary tract infections and systemic infection. Early echocardiographic assessment, microbial identification, and timely multidisciplinary management are essential to achieving favorable outcomes in such rare cases.