A new study examined patients with cystic fibrosis to learn more about the cause of persistent infections following treatment. Researchers from the University of Washington (UW) School of Medicine in Seattle and the University of Iowa in Iowa City published their findings in Cell Host & Microbe.
Modulators are a new drug that help treat the underlying cause of cystic fibrosis. However, many people remain infected with bacteria in the lungs following treatment.
“Modulators are amazing new treatments that have really improved people’s quality of life,” said Samantha Durfey, PhD, lead researcher and former postdoctoral scholar at UW Medicine, in a news release. “However, infections manage to stick around, even with the best modulator, and we need to understand why.”
In the study, “Pseudomonas Infections Persisting After CFTR Modulators Are Widespread Throughout the Lungs and Drive Lung Inflammation,” researchers inspected patients’ lungs using bronchoscopes to sample regions with differing amounts of inflammation, damage and infection prior to beginning therapy. Then, they repeated the process one year after treatment to see where infection and damage remained as well as what lung characteristics were associated with persistent infection.
“A leading idea in the field is that patients remain infected because highly damaged lung regions can’t clear the infection, similar to how damaged tissues in wounds get infected. If a similar process is responsible for persistent CF lung infections, research can focus on these areas,” said UW Medicine pulmonologist Siddhartha Kapnadak, MD, who led the lung sampling.
Dr. Durfey said the results revealed both good and bad news.
“The good news was that when infections cleared, lung inflammation almost completely resolved. Thus, future lung damage could be lessened in people who clear,” she said. “However, people who remained infected had infection and inflammation everywhere we looked, including lung area with very little damage [prior to treatment].”
The study suggests lung damage might not be the primary cause of ongoing infections and raises concern that the lung function of people with CF and bacterial infection could continue to deteriorate, despite therapy.
“Now, we have to understand how infection can persist in all areas of the lungs,” said senior researcher Pradeep Singh, MD, a UW Medicine pulmonary care physician and professor of medicine and microbiology at the UW School of Medicine. “The bacteria may adapt in news to resist clearance even when the least damaged lung regions are treated with the best drugs we have.”
Although the study advanced knowledge in this area, Dr. Durfey said there are more possibilities to consider and more research that needs done.
