New Insights into Cystic Fibrosis-related Chronic Lung Infections Likely to Lead to Better Therapies

Better ways of treating chronic lung infections in patients with cystic fibrosis (CF) are likely to result from scientific advances in the understanding of how Pseudomonas aeruginosa bacteria evolve and adapt during infections, according to a recently published review from the University of Liverpool, working in collaboration with the University of York.

The review appeared in the journal Trends in Microbiology, under the title “Pseudomonas aeruginosa Evolutionary Adaptation and Diversification in Cystic Fibrosis Chronic Lung Infections,” as part of a special themed issue on Microbial Endurance.

CF patients often experience a build up of mucus in lung airways that traps bacteria, making them more prone to lung infections. One such bacteria is P. aeruginosa, which is usually harmless to healthy individuals, but in people with CF can cause antibiotic-resistant infections and is difficult to clear from the lungs. P. aeruginosa is the most important pathogen in CF, affecting over 80 percent of all patients. In adults, the resulting infection is often chronic, decreasing lung function and leading to overall morbidity.

The review reinforced the importance of advancements, especially the arrival of affordable high-throughput genome sequencing, in enabling rapid progress in the research community’s knowledge of how P. aeruginosa adapts and evolves in CF patients.

“Currently we know that populations of P. aeruginosa that infect CF lungs harbour huge amounts of diversity, including variation in antibiotic resistance and secretion of toxins. This diversity is dynamic over time, making accurate diagnosis and treatment challenging,” the study’s lead author, Professor Craig Winstanley, from the university’s Institute of Infection and Global Health, said in a press release. “Experimental work is now beginning to provide insights into what drives this evolution during infections, including the role of social interactions.”

P. aeruginosa poses a specific challenge, due to its ability to rapidly develop resistance to antibiotics across several generations. “Given the limited efficacy of current antibiotics, we now need to establish how this bacterial evolution and dynamic diversity affects patients, in order to design alternative treatment strategies,” Professor Winstanley said. “One potential area of future work is to see whether the evolutionary trajectory of P. aeruginosa in CF lung infections could be manipulated to minimise symptoms and improve patient outcomes.”

CF affects more than 10,000 individuals in the U.K.