New research shows that microbes contributing to cystic fibrosis are able to survive in saliva and mucus that is chemically heterogeneous.

The study, which evaluated sputum samples from 22 pediatric CF patients, found that the microbiologic environment can differ between patients, and even within the same patient at different points in time. Researchers also noted that a number of samples contained the gas hydrogen sulfide, a form of sulfur that reacts with and removes oxygen from the environment. Patients who had detectable hydrogen sulfide in their sputum tended to have less severe disease symptoms.

The findings shed a light on the conditions under which CF microbes can survive, said senior study coauthor Dianne K. Newman, PhD, professor of biology and geobiology at the California Institute of Technology, Pasadena, California.

“The diversity and adaptation of disease-causing microorganisms within the CF lung environment, in part, is what renders CF infections so difficult to eradicate,” Newman said. “Few studies have attempted to characterize the chemistry of mucus collecting in CF airways, yet such measurements are essential if we are to understand how microorganisms survive in the lung and impact the microenvironment.”

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