ePS06.7 Factors associated with failure to eradicate first or newly acquired Pseudomonas aeruginosa in patients with CF

Respiratory infections with P. aeruginosa (PA) are a leading cause of morbidity-mortality in Cystic fibrosis (CF) patients. Several protocols for eradication are in use, however, the optimal antibiotic dosage, mode of delivery and duration of therapy has not been standardized. Still, ∼20% of the infections cannot be eradicated leading to chronic infection. Aims To analyze the rate of eradication failure of 1 st /new PA infection and to identify clinical factors associated with eradication failure. Methods 183 patients' files from 6 CF Centers in Israel and 1 in Spain were included. Demographic and clinical data for 7 years (2007–2013) were retrospectively analyzed. Results For 131 patients (72%) eradication was successful, and were divided into 2 groups: Absolute eradication – successful eradication and completed anti-PA treatment (n = 92) and Presumed eradication – successful eradication with ongoing anti-PA inhalations (n = 39). For 52 patients eradication failed: 34/52 chronically infected and 18/52 intermittent infection. Older age at CF diagnosis, older age at 1 st /new PA infection, lower FEV1%, less sputum cultures taken 1 year prior to 1 st /new isolation, previous documented PA colonization and multi/pan-resistant PA strains were all found to be associated with failure to eradication. BMI, gender, and CF-related diabetes did not influence successful eradication. No significant difference was seen in terms of HRCT Brody scores. Additionally, the different eradication protocols did not change the outcome. Conclusions Early diagnosis, increased follow-up and appropriate therapy are all required in order to enhance the rate of efficient eradication of PA in CF patients.