Fulminant infectious endocarditis caused by Staphylococcus aureus with pseudoaneurysms in the superior mesenteric, hepatic, and popliteal arteries: a case report

Staphylococcus aureus infectious endocarditis has a high mortality, major causes of death being cardiac failure, systemic embolism, and sepsis. Pseudoaneurysms, a rare complication of this infection, are not invariably fatal with appropriate treatment. A previously healthy 32-year-old man was found to have multiple cerebral infarctions, and infectious endocarditis with mitral valve vegetation was diagnosed by echocardiography. Because methicillin-resistant Staphylococcus aureus (MRSA) was identified from blood cultures, vancomycin was administered. Massive intracerebral hemorrhage in the left temporo-occipital lobe occurred in the patient on the 3rd day after admission, and the hematoma was completely removed surgically. Another hemorrhage was identified in the right occipital region on the 7th hospital day, which led the patient deep coma. Blood cultures on the 10th day were negative for MRSA; however, imaging studies revealed pseudoaneurysms in the superior mesenteric, hepatic, and left popliteal arteries 3 weeks after admission. No surgical indication was applied to these pseudoaneurysms because the patient remained comatose. On the 78th day after admission, the patient's blood pressure suddenly dropped and he died. Autopsy demonstrated massive bleeding in the abdominal cavity caused by rupture of the superior mesenteric artery pseudoaneurysm. Our patient's clinical course was fulminant, his endocarditis being complicated by cerebral infarctions, intracranial hemorrhages, and multiple pseudoaneurysms within 3 weeks of admission. In retrospect, he may have survived if emergency resection of the mitral valve vegetation had been performed on the first or second day of admission; however, the in-hospital mortality rate after such surgery is high.