Researchers seek safer cystic fibrosis test

Researchers from The University of Arizona colleges of pharmacy and medicine are teaming up to try to invent a novel non-invasive lung test for cystic fibrosis sufferers.

Eric Snyder, assistant professor at the College of Pharmacy, is the principal investigator on the study, “Quantification of Exhaled Condensate Using Bronchoalveolar Lavage in Cystic Fibrosis.” Snyder will work with College of Medicine faculty Cori Daines and Wayne Morgan on the project.

Cystic fibrosis (CF) is a disease that affects the lung. According to the Cystic Fibrosis Foundation, about 30,000 children and adults in the United States (70,000 worldwide) suffer from CF. The disease results from a genetic alteration that lowers the function of chloride channels in the lung, which leads to a dry lung. The drier a CF patient’s lungs, the more dangerous his disease.

The fluctuations of sodium, potassium and chloride in the lung are all important in keeping the lung wet and are of particular importance in cystic fibrosis.

Studies in the past using cell lines or animal tissues have shown that the administration of a common drug used in cystic fibrosis, a beta-agonist, increases the amount of chloride on cells and this should help keep the lungs wet. The problem is there is not currently an easy way to measure the amount of chloride on a person’s lung cells in order to optimize his therapy.

Today, measuring what is on lung cells requires an invasive test called bronchoalveolar lavage. Although bronchoalveolar lavage is typically used to determine the level of disease severity by exploring inflammatory markers, Snyder notes that it could also be used to collect signs of chloride, and possibly lung dryness.

During bronchoalveolar lavage, the patient is anesthetized and a tube is inserted into his lung. Next a small amount of water is sprayed into the lung’s airway and then sucked out through the tube. This fluid can then be analyzed for a variety of factors.

The bronchoalveolar technique is invasive and carries some risk. The aim of Snyder’s study is to develop a safer, non-invasive procedure that can measure some of the data that can be taken with a bronchoalveolar lavage with comparable accuracy.

The non-invasive procedure that Snyder’s research will explore involves measuring signs of lung dryness by using a patient’s breath that is condensed in a cooling chamber.

To do this, the team will first have a patient breathe into a machine in Snyder’s laboratory in the College of Pharmacy. The machine condenses the patient’s breath in a cooling chamber so that the research team can measure the amount of sodium, potassium and chloride it contains. Immediately after this non-invasive test, the patient will go to University Medical Center for a bronchoalveolar lavage performed under the direction of Daines and Morgan.

Once the brochoalveolar lavage is completed, the team will compare the amount of sodium, potassium, and chloride ions gathered in that test to the amount gathered non-invasively in the breath test. This will allow the team to see if the non-invasive test is as accurate as the invasive technique.

“This research will provide data to further explore the development of a non-invasive tool to measure airway fluid composition,” says Snyder. “It will provide important preliminary data for future, larger studies in this patient population. Our goal is to invent a non-invasive test which will aid in the assessment and treatment of cystic fibrosis.”

The study is funded by a Faculty Small Grant Award of close to $10,000 from The University of Arizona Foundation. It begins this month.

Photo: Cori Daines, MD (left) and Eric Snyder, PhD.

Posted Sept. 9, 2009