Chronic Pseudomonas aeruginosa infection definition: EuroCareCF Working Group report.

Chronic pulmonary infection with P. aeruginosa develops in most patients with cystic fibrosis (CF); by adulthood 80% of patients are infected and chronic P. aeruginosa infection is the primary cause of increased morbidity and mortality in CF. Chronic infection is preceded by an intermittent stage of infection. The initial stage is characteristically followed by the gradual emergence of mucoid variants of the colonizing strains and a rise in anti-Pseudomonas antibodies. In addition to optimizing existing therapeutic strategies, effective new agents need to be identified. Studies in patients with CF are particularly challenging: the progressive nature of the disease and the wide variation in severity influence considerably the outcome of drug testing. A validated, universally accepted, and clinically useful classification of patients infected with P. aeruginosa, particularly those chronically infected, is needed that can be used as both a criterion for patient selection for clinical trials and as a study endpoint.

Pulmonary exacerbation: towards a definition for use in clinical trials. Report from the EuroCareCF Working Group on outcome parameters in clinical trials.

Pulmonary exacerbations represent a key outcome variable in clinical trials of cystic fibrosis (CF). As there is variation in the trigger for use of intravenous antibiotics compared to the use of oral antibiotics or new nebulised therapy for treatment of exacerbations, the consensus view is that use of intravenous antibiotics cannot be regarded as the key defining character for an exacerbation on its own. The consensus view is that the clinical need for additional treatment as indicated by a recent change in clinical parameters provides the best definition of an exacerbation. Which parameters to include as well as the problems associated with the use of scoring systems and symptom clusters are being discussed.