While tremendous advancements have been made over the past several decades in treating cystic fibrosis (CF), many CF therapies are not one-size-fits-all.  What works for adult patients doesn’t necessarily help very young patients.  And yet, it’s critical to begin therapies early in life to delay lung disease caused by CF from progressing.

Inhaled hypertonic (extra salty) saline is one such therapy recommended for many CF patients age 6 or older, but its effectiveness has never been evaluated in patients age 5 or younger.  Despite this, since 2007 inhaled hypertonic saline has been increasingly used among U.S. children with CF ages 2 to 5.

Several years ago, Australian researchers stumbled on the benefits of hypertonic saline when they noticed that surfers with CF had fewer respiratory flare-ups than people with CF who didn’t surf.  The researchers speculated that the salty mist of ocean water lessened respiratory CF symptoms and their subsequent study confirmed their hypothesis.

The study

Dr. Margaret Rosenfeld of Seattle Children’s Research Institute and other researchers set out to test the efficacy of this therapy in very young patients. Their study, Inhaled Hypertonic Saline in Infants and Young Children With Cystic Fibrosis, was recently published in JAMA. They hypothesized that hypertonic saline solution would decrease the rate of pulmonary exacerbations (respiratory flare-ups) in children with CF age 5 or younger. “This is the first study of its kind with really young children with CF. If we want to prevent inexorable lung damage in CF patients, then we need to identify therapies that are effective in very young children,” said Dr. Rosenfeld.

A total of 321 children age 5 or younger with CF from 30 CF centers across the country participated in this randomized, controlled trial. One hundred fifty-eight patients received hypertonic saline; the control group, consisting of 163 patients, received isotonic (normal) saline. Pulmonary exacerbations rates were measured in both groups during the 48-week period they received the saline treatments.


Dr. Rosenfeld and co-investigators were surprised by their findings: hypertonic saline did not reduce the rate of pulmonary exacerbations in those study participants who received it. In addition, hypertonic saline did not demonstrate any significant effects on weight, height, respiratory rate, oxygen saturation, antibiotic use or parent report of respiratory signs and symptoms.

“While we’re not undoing any guidelines, based on our findings, we certainly hope that hypertonic saline will not be used at this point in children with CF age 5 and younger,” Dr. Rosenfeld added.

Dr. Rosenfeld conjectured that hypertonic saline may not have prevented pulmonary exacerbations in these very young children because pulmonary exacerbations are largely caused by viral respiratory infections in this age range. In addition, very young children with CF generally have mild symptoms, so there is not a lot of room for improvement.

What’s next?

A small sub-study that measured lung function in some of the infants enrolled in the same trial (described above) showed improvement in the hypertonic-saline treated infants compared to the infants treated with the control agent, suggesting that further research should be directed at evaluating whether hypertonic saline can delay structural airway damage in very young children with CF even if it doesn’t improve symptoms. Dr. Rosenfeld and her colleagues plan to seek funding for such a study.

In addition, Dr. Rosenfeld is currently leading a new study investigating the use of a pediatric formulation of Kalydeco (a new medication that targets the genetic defect which causes CF) for patients ranging in ages 2 to 5. She and other physicians will evaluate the safety and tolerability of the drug while also looking at measures of clinical activity like the effect on sweat chloride on the surface of the skin.


Cystic fibrosis (CF) is a disease passed down through families that causes thick mucus to build up in the lungs, digestive tract and other areas of the body.  It is life-threatening and one of the most common chronic lung diseases in children and young adults.

Hypertonic saline has a higher concentration of salt than isotonic saline does. Because of this, hypertonic saline may be able to draw out fluid and mucus more effectively and, as a result, reduce respiratory infections – a common symptom of CF. Lung damage caused by repeated respiratory infections is the leading cause of death for people with CF.


  • Approximately 30,000 children and adults in the U.S.
  • Approximately 70,000 people worldwide have CF.
  • More than 70% of patients are diagnosed by age two.
  • Approximately 55% of the CF patient population is age 17 or younger.
  • The predicted median age of survival for a person with CF is in the late 30s.

Cystic fibrosis expert available for media interviews

Margaret Rosenfeld, MD, MPH is the associate director of the Center for Clinical and Translational Research at Seattle Children’s Research Institute and associate professor in the Department of Pediatrics at the University of Washington School of Medicine. She is also co–director of the Seattle Children’s Fellows College and director of the Clinical Research Scholars Program. Her clinical interests focus on the diagnosis and management of respiratory illnesses in children of all ages. Her research program focuses on the assessment and treatment of early cystic fibrosis (CF) lung disease, including infant and preschool lung function tests, determining risk factors for early acquisition of Pseudomonas aeruginosa and clinical trials in infants with CF.

Dr. Rosenfeld is also an investigator in a national network investigating rare disorders of mucociliary clearance, including primary ciliary dyskinesia. She serves as CF consultant to the Washington State Newborn Screening Program.

Additional Resources

  • For more information about CF, visit the Cystic Fibrosis Foundation.
  • For more information about recent breakthroughs in cystic fibrosis treatments, visit: Benefits of CF Drug Confirmed.
  • For more information about clinical care for patients with CF at Seattle Children’s, visit: Pulmonary and Sleep Medicine.
  • Photo credit: Kyle Monk. Kyle worked with the CF Foundation to create dramatic, powerful, and intimate portraits of people with cystic fibrosis to help bring awareness to this genetic disease.  For more information about his photo series of patients with CF, visit: Kyle Monk Photography.

If you’d like to arrange an interview with Dr. Margaret Rosenfeld, please contact Children’s PR team at 206-987-4500 or