頭部造影MRIとMRAで経時変化を観察した感染性心内膜炎に合併した脳血管病変

Cerebral Artery Lesion in a Patient with Infective Endocarditis : Serial MRI and MRA Findings of Cerebral Artery Stenosis

　要旨　症例は22歳，男性。入院時より感染性心内膜炎と診断され抗生剤の投与が行われたが，第7病日に細菌性髄膜炎を併発した。第15病日のMRAで右中大脳動脈M1の狭窄が認められ，頭部造影MRIで同部位の血管周囲に造影効果が確認された。狭窄部位の血管周囲に造影効果を認めたことより，脳血管炎が疑われた。抗生剤の投与により感染性心内膜炎と脳血管病変の上記画像所見は改善した。感染性心内膜炎による脳血管病変では，頭部造影MRIとMRAを組み合わせて施行することが診断と治療効果の評価に有用であると考えられた。

　We reported a case of infective endocarditis （IE） complicated with bacterial meningitis and cerebral artery stenosis. A 22-year-old man was admitted to our hospital because of IE. Although benzylpenicillin administration was continued, he abruptly developed consciousness disturbance on the seventh day. His cerebrospinal fluid indicated bacterial meningitis. MRI with gadolinium （Gd） enhancement showed septic embolism in the left parietal lobe and bi-linear enhancement on the right middle cerebral artery （MCA）. MRA demonstrated narrowing of the MCA at the same site as the bi-linear Gd enhancement. We considered that these findings show narrowing of the MCA was due to cerebral arteritis. Intravenous administration of ampicillin and cefpirome gradually improved both IE and cerebral artery stenosis. We wish to emphasize that combination of MRI with Gd enhancement and MRA may be useful not only for diagnosis of cerebral artery stenosis but also for evaluation of treatment effect.