Extended-Spectrum β-Lactamase-Producing Bacterial Infections in Adult Solid Organ Transplant Recipients

BACKGROUND: Limited research is available evaluating infections due to extended-spectrum beta-lactamase (ESBL) producing organisms in adult recipients of solid organ transplant (SOT). OBJECTIVE:: To evaluate clinical response and rate of recurrence of ESBL-producing organisms in 20 SOT recipients. METHODS: In a retrospective case series, records of adult SOT recipients with an admitting diagnosis of infection and a positive culture for an ESBL-producing organism from January 2003 through August 2006 were reviewed. RESULTS: Twenty patients met inclusion criteria. The median time to infection following Transplant was 3.5 years (range 1-23 years). Overall, 85% of the patients received inadequate empiric antibiotic therapy, including ciprofloxacin or piperacillin/tazobactam, to manage their infection. Nineteen patients had clinical resolution; however, 12 patients required at least 1 readmission due to infection recurrence. One patient's death occurred during the study period. The median time to readmission for a recurrence was 41 days (18-455 days). All recurrent infections were caused by the same ESBL-producing pathogen and 10 of 12 (83%) infections occurred at the same site as the initial infection. Among patients with recurrent infections, 75% received inadequate empiric therapy upon readmission. All 12 patients with recurrent infections had successful clinical responses to both initial and recurrent infections. CONCLUSIONS: The provision of inadequate empiric therapy for new and recurrent infections due to ESBL-producing pathogens was common in this study population. SOT recipients with a history of infection due to an ESBL-producing organism presenting with a new infection should receive adequate empiric therapy with a carbapenem agent until a definitive diagnosis can be established.