The impact of resistant bacteria in respiratory secretions on the outcome of lung transplantation

Introduction: Antibiotic treatment may cause growth of resistant bacteria in respiratory secretions. We assessed the association between antibiotic treatment of lung transplant recipients and acquisition of quinolone resistant gram negative bacteria (QR-GNB), and the impact of such colonization on mortality and lung rejection (BOS). Methods: We examined data from lung transplant recipients for antibiotic treatment, GNB in respiratory secretions, BOS, and mortality. Results: 126 patients were included. Median percentage of days with antibiotics was 2.8% in patients with no growth, 11.1% in patients with quinolone sensitive GNB (QS-GNB), and 26% in patients with QR-GNB. Age adjusted mortality hazard ratio was 9.2 (95% CI, 1.27-78.9) for patients with QR-GNB compared with QS-GNB. Age adjusted hazard ratios for BOS were: 3.6 (1.1-11.6) for QR-GNB compared with no growth, and 3.7 (1.33-10.3) for QR-GNB compared with QS-GNB. Conclusions: Antibiotic treatment was associated with QR-GNB. Airway colonization with QR-GNB was associated with mortality and with BOS. We suggest that narrow spectrum antibiotics should be preferred in lung transplant recipients.