Hemorragic presentation of Listeria Monocytogenes rhombencephalic abscess

Abstract

Listeria monocytogenes (LM) bacterium is a cause of central nervous system (CNS) infection and the most common cause of rhombencephalitis in immunocompetent elderly. A prompt identification of this condition should be always desirable, since its clinical manifestations are often unspecific with prodromal symptoms leading to high rates of morbidity and mortality if underestimated. CNS listeriosis magnetic resonance imaging (MRI) findings are generally not specific. However, in the appropriate clinical setting, focal brainstem hyperintensity on T2-weighted pulse sequences associated with ring-enhancement pattern after i.v. contrast media injection should be suspicious of LM abscess. The diagnosis cannot exempt from anamnestic-clinical investigation data correlation to exclude mimicking. We report the case of a 72-year-old man with fever, headache, vomiting, and persistent hiccups with an increasing walking difficulty. A progressive worsening of the state of consciousness led him to a stupor state. Brain MRI examination detected multiple rhombencephalic abscesses. Among these, one was with atypical hemorrhagic presentation. The presence of hemorrhage, uncommon for listeria abscesses, may further complicate their detection, with consequent delayed treatment. The diagnostic hypothesis was confirmed by cerebrospinal fluid examination, which was confident with LM infection. Clinical and neuroradiological state improved after antibiotic therapy.