Bacterial intracranial aneurysms.

The treatment of 13 patients with bacterial intracranial aneurysms is reported. The incidence of bacterial intracranial aneurysms was 4% of all patients admitted with intracranial aneurysms and 3% of all patients admitted with bacterial endocarditis. Each patient had neurological signs or symptoms suggestive of intracranial disease prior to the diagnosis of an aneurysm. Alpha Streptococcus was the most common infecting organism. All patients were treated with specific, high-dose antibiotics, and five patients underwent surgery as well. There were no surgical deaths. Six of eight nonsurgically treated patients died. A review of the literature confirms a high mortality for patients treated with only antibiotics, and a low mortality for elective surgery. The authors conclude that 1) patients with bacterial endocarditis, who develop sudden severe headache, focal neurological signs or symptoms, or seizures, should undergo serial cerebral angiography every 7 to 10 days throughout their hospitalization; 2) if an aneurysm is identified it should be excised whenever possible; and 3) patients with proximal or multiple aneurysms should be considered for surgery.