Listeria monocytogenes bacteremia mimicking the systemic metastasis of adrenal cancer: a case report.

Background: Listeria monocytogenes is a causative agent of food poisoning and is also known to cause invasive diseases, such as bacteremia, meningitis, and encephalitis, in neonates, elderly and immunocompromised patients. However, the clinical course of a multi-organ disseminated disease secondary to bacteremia has been rarely reported.

Case Presentation: A 76-year-old woman undergoing immunosuppressive therapy for rheumatoid arthritis presented to our outpatient clinic with a chief complaint of weight loss. Computed tomography showed a left adrenal mass, enlarged lymph nodes, and multiple intrahepatic nodules. Positron emission tomography demonstrated accumulation of fluorodeoxyglucose F18 in the adrenal mass, lymph nodes, hepatic nodules, and bones, leading to the suspicion of systemic metastasis of adrenal cancer. She subsequently developed a fever. Blood culture results led to the diagnosis of Listeria monocytogenes bacteremia. Percutaneous needle biopsy of the adrenal lesion revealed no malignant findings. After extended treatment with antimicrobial agents, the fever resolved, along with the disappearance of the systemic lesions.

Conclusions: This case shows that listeriosis can lead to lesions in the adrenal gland, which can exhibit clinical presentation that is difficult to differentiate from malignancy on imaging studies.