Postoperative antimicrobials after lung transplantation and the development of multidrug-resistant bacterial and Clostridium difficile infections: an analysis of 500 non-cystic fibrosis lung transplant patients

Background: Broad-spectrum antimicrobials are given prophylactically post-transplant, although these agents are a risk factor for multidrug-resistant (MDR) infections and Clostridium difficile infection (CDI). This study aimed to determine whether an association exists between the duration of antimicrobials given early post-transplant and the development of MDR infections or CDI. Methods: A single-center retrospective analysis was performed on lung transplants from September 2009 to August 2014. Patients were excluded for cystic fibrosis (CF) or postoperative survival less than 30 d. Qualifying infections were defined as any new positive MDR bacterial culture or C. difficile assay from postoperative day 7–90 d after a broad-spectrum antimicrobial. Results: A total of 500 patients, 61% male, were identified, median age of 62 yr. MDR infections occurred in 169 (34%) and CDI in 31 (6%). Non-ICU days were associated with a decreased risk of MDR/CDI (OR 0.891, p = 0.0002), and duration of Gram-positive antimicrobials (OR 1.073, p = 0.0219) was associated with an increased risk. Conclusions: One-third (34%) of non-CF lung transplants develop MDR infections and 6% develop CDI within 90 d of postoperative antimicrobials. The duration of Gram-positive antimicrobials may increase the risk of MDR/CDI, while early transfer from the ICU may have a protective effect.