Abstract
An 87-year-old woman was admitted to our hospital (day 0) because of acute disorientation caused by multiple acute intracerebral hemorrhages. T2*-weighted magnetic resonance imaging (MRI) at admission revealed multiple subcortical old microbleeds indicative of cerebral amyloid angiopathy. Microbleeds in the right cerebellar hemisphere and acute spotty ischemia in the left cerebellum were also identified. The patient had been afebrile, and blood examinations on day 7 were within normal limits of inflammatory findings without antibiotics. On day 11, she developed a high fever and blood culture was performed. Her fever resolved within 2 days of antibiotic administration, although subsequent findings revealed her blood culture was positive for Staphylococcus aureus. Echocardiogram revealed bacterial vegetation in the mitral valve and moderate mitral regurgitation, with a diagnosis of infectious endocarditis (IE). Follow-up MRI demonstrated multiple spotty acute infarctions and an increased number of microbleeds. The patient may have been infected via peripheral infusions administered during the first few days after admission. However, considering the coexistence of acute hemorrhagic and ischemic lesions on MRI, as well as the acute lesions in the cerebellum, it is possible that IE was already latent on admission, and that the multiple brain hemorrhages might have been caused by IE rather than by cerebral amyloid angiopathy.