Population dynamics and adaptation of Pseudomonas aeruginosa during chronic lung infection in cystic fibrosis.

摘要

Pseudomonas aeruginosa is the most frequently isolated organism from patients with cystic fibrosis. Colonization occurs in early childhood and persists throughout the lifetime of patients. During chronic airway infection, P. aeruginosa is generally thought to evolve into a chronic phenotype characterized by acquisition of a number of mutations that results in loss of virulence factors required for acute infection. However, P. aeruginosa cultured from sputum exhibits a wide range of colony morphologies and suggests that P. aeruginosa in chronic airway infection has an unexplored level of diversity. To examine the population dynamics of P. aeruginosa in CF airways, we monitored morphotypes isolated during periods of pulmonary exacerbation in four CF adult patients with quantitative and quantitative microbiology. Phenotypic profiling was carried out for P. aeruginosa virulence factors generally considered to be lost during chronic infection. Results from this study indicate that P. aeruginosa CF population is highly diverse and virulence factors are still present in chronic infection.