Antibiotic-treated Streptococcus sanguinis intracranial mycotic aneurysm

We report the case of a woman 33 years of age with infective endocarditis-related intracranial mycotic aneurysm (IMA) caused by a Streptococcus sanguinis infection. The clinical diagnosis was confirmed by the findings of magnetic resonance imaging, magnetic resonance angiographic (MRA) studies, echocardiographic studies, and a positive blood culture result. She underwent antimicrobial treatment only (ceftriaxone intravenously for 8 weeks and penicillin V orally for 6 weeks). The regression and disappearance of IMA were demonstrated by a series of MRA follow-up studies.