診断の遅延した感染性動脈瘤再破裂例の1手術例

Infectious Aneurysm Rerupture Caused by Delayed Diagnosis: An Operative Case Report

Ⅰ．はじめに

　1869年にChurchが初めて，感染性心内膜炎（infectious endocarditis：IE）を伴った感染性脳動脈瘤の症例，破裂中大脳動脈瘤で左麻痺から突然死に至った例を報告してから1世紀以上が経過している⁴⁾．また感染性脳動脈瘤は，IEの1.2～4％に併発するとわかってきた^1,6,11,12)．しかし，近年も破裂動脈瘤例の予後は不良とされ，死亡率30～80％などの報告がある^2,3,7,12)．今回，われわれはIEの診断が遅延し感染性脳動脈瘤形成，破裂，かつ再破裂を来し緊急手術施行した症例を経験したので，早期診断と治療方針について検討し報告する．

　A 21-year-old febrile woman with sudden onset of headache and semicoma was transferred to our institute. CT and 3D-CT angiography showed subaracnoid hemorrhage and intracranial hemorrhage in the left hemisphere due to a saccular aneurysm at the occluded M2 portion of the middle cerebral artery (MCA). Her present illness started with a toothache and lumber pain 3 weeks earlier. Echocardiography revealed active infective endocarditis. We could have treated her by administering antibiotics, but during a cerebral angiography, she became comatose due to an aneurismal rerupture. Immediately, an emergency operation for aneurismal trapping was performed, but she died 19 days later because of left hemispheric swelling.

　We report a relatively rare case of infectious aneurysm at the proximal artery and discuss the pitfalls of its diagnosis and treatment. We should educate general physicians about infectious endocarditis because misdiagnosis or delayed diagnosis of infectious aneurysm due to endocarditis results in unpleasant outcomes. We should treat infectious aneurysm at the proximal side artery by first administering antibiotics, and if necessary, subsequent direct surgery of the aneurismal trapping should be performed with a bypass. Unnecessary invasive treatment must be avoided while the disease is in the active infectious stage.