2022 Volume 27 Issue 1 Pages 159-
A 76-year-old woman presented to our hospital with abnormal behavior and left hemiplegia ongoing for the last 4 days. On admission, she had fever, and magnetic resonance imaging（MRI）of the head showed a lesion along the nerve fiber tracts of the central nervous system with a partial contrast-effect. Blood tests revealed a mild inflammatory reaction, and whole-body computed tomography showed no other apparent cause of the fever；thus, empiric antibacterial therapy was started, with brain abscess and malignant lymphoma as differential diagnoses. Listeria monocytogenes was detected in the blood culture at admission；however, the cerebrospinal fluid culture was negative for L. monocytogenes. Brain biopsy was performed to confirm the diagnosis. As a result, neoplastic disease was excluded, and we diagnosed the presence of brain abscess caused by L. monocytogenes. After approximately 6 months of antibacterial treatment, the findings of cerebrospinal fluid and head MRI improved, and the patient was discharged with improved symptoms. L. monocytogenes is known to migrate along the nerve fiber tracts in the central nervous system and present a characteristic distribution pattern in the brain. Recognition of this feature may lead to early diagnosis of this disease and improve the outcome.
