Causes of Failure to Eradicate Acquisition of Pseudomonas Aeruginosa in Patients with CF

Background: Respiratory infection with P. aeruginosa (PA) is a leading cause of morbi-mortality in patients with Cystic fibrosis (CF). It is associated with a more rapid decline in pulmonary function, worsening nutritional status, more hospital admissions and a shorter life expectancy. Although several protocols for eradication of PA after the first isolation are in use, the optimal antibiotic combination, dosages, modes of delivery and duration of therapy remains unresolved. Still, 10-20% of PA infections cannot be eradicated and become chronic infection; therefore, it is imperative to understand what are the factors associated with failure to eradicate PA in CF. Aims: To analyze the rate of eradication failure of first or new PA infection and to identify clinical and laboratory factors that are associated with eradication failure. Methods: Records of 130 CF patients treated at the Hadassah Medical Center and in other 5 CF centers in Israel were reviewed. Demographic, clinical and laboratory data collected over the last 7 years were retrospectively analyzed. Results: Older age, pancreatic insufficiency status, less often visits to the CF center, multi/pan-resistant PA, colonization of PA in the past, later age at diagnosis, air-trapping in the CT scan, later age at CF diagnosis, and no-treatment with hypertonic saline were identified as risk factors for eradication failure. After multivariate analysis, the lasts two issues were the more strongly associated with failure to eradicate PA. Conclusions: Early diagnosis and appropriate therapy is required in order to augment the rate of efficiently eradication of PA in patients with CF