Epidemiology and Clinical Characteristics of Listeria monocytogenes Bacteremia in a Taiwanese Medical Center

Background/Purpose: There have been many reported cases of Listeria monocytogenes bacteremia in Europe and the United States, but only a few from Taiwan. The present study was undertaken to analyze the clinical characteristics of patients with L. monocytogenes bacteremia in Taiwan. Methods: Patients with culture-confirmed L. monocytogenes bacteremia were identified at Chang Gung Memorial Hospital between January 2001 and December 2008. The clinical features and outcomes of the patients and the antimicrobial susceptibilities of the clinical isolates were analyzed. Results: Forty-three patients, including two newborn babies (4.7%) and 41 adults (95.3%), with at least one episode of Listeria bacteremia were identified. Forty-two (97.7%) of these patients had underlying diseases. Thirty-three patients (76.7%) had fever, 14 (32.6%) had experienced respiratory distress, and 11 (25.6%) had reported changes in consciousness. Twelve patients died within 14 days of infection, corresponding to a case-fatality rate of 27.9%. All the clinical isolates tested were susceptible to ampicillin, penicillin and vancomycin. Conclusion: Most cases of L. monocytogenes infection occurred in adults with underlying diseases, especially malignancy, and only two cases of neonatal L. monocytogenes bacteremia were identified over the 8-year period. Penicillin, ampicillin and vancomycin could be used for the treatment of L. monocytogenes bacteremia, with the case-fatality rate lower for patients who received appropriate treatment.