Brain abscess due to Listeria monocytogenes: case report and literature review.

Listeria monocytogenes is an uncommon cause of brain abscess. Of a total of 14 cases of L. monocytogenes brain abscess (one described for the first time and 13 reported previously in the English-language literature), seven (50%) occurred in patients with leukemia and recipients of renal transplants; four (29%) of the cases occurred in previously healthy individuals. Common clinical findings were similar to those in brain abscess due to other causes and included fever (57%), headache (57%), and focal neurologic signs (64%). Distinctive, however, was the unusually high frequency of associated meningitis and bacteremia; blood cultures were positive in all eight cases in which they were performed. Eight (57%) of the 14 patients died. L. monocytogenes should be included in the differential diagnosis of brain abscess in patients with leukemia and in renal transplant recipients. Listerial brain abscess is highly unlikely when blood culture results are negative.