Cystic Fibrosis Screening & Diagnosis

If your baby tested positive for cystic fibrosis (CF) after having the newborn screening test, we're here to help. Our team of specialists from the University of Chicago Medicine Cystic Fibrosis Center and the Department of Human Genetics provide the full range of testing and counseling services to help families that may be affected by cystic fibrosis. If a diagnosis of cystic fibrosis is confirmed, our experts can provide advanced, compassionate care to treat this complex, chronic disease.



Newborn Cystic Fibrosis Test

All birthing hospitals in Illinois offer CF testing as part of the usual newborn screening process.

Before each newborn leaves the hospital, a small amount of blood is collected from the infant to be used for variety of important screening tests. Newborn screening for cystic fibrosis is one of the conditions screened and has two components:

• Measurement of immunoreactive trypsinogen (IRT)
• Assessment of the most common genetic mutations causing CF

Infants with positive newborn screening tests (elevated IRT and one or two common CF mutations) will require prompt follow-up to determine if the child has CF or is an unaffected carrier for the CF trait. A sweat test is a follow-up assessment used to determine if the child has CF.

Early detection and treatment of cystic fibrosis leads to improved nutrition, infection control and overall outcome.

Positive Test Results

Notification of positive results will go to the child's primary care provider/pediatrician, who will then notify the family. Most infants with a presumptive positive newborn screening test will either be affected with CF or will be unaffected carriers of the CF trait.

Pediatricians and clinicians should refer the infant to a qualified Cystic Fibrosis Foundation-accredited care center as mandated by Illinois Department of Public Health for confirmatory testing by sweat chloride, also referred to as a sweat test. UChicago Medicine has an accredited care center that offers sweat testing and genetic counseling for families with children who have tested positive for the newborn CF test.

Sweat Test

If your child tested positive for the newborn CF screening, a sweat test will be needed to confirm the diagnosis. The sweat test determines the amount of chloride (a component of salt) in sweat.

There are no needles involved in the procedure. In the first part of the test, an electrode is attached to the arm or leg to stimulate sweating. Individuals may feel a tingling sensation in the area or a feeling of warmth. The second part of the test consists of collecting the sweat in a plastic coil. Thirty minutes later, the collected sweat is sent to the hospital laboratory for analysis.
False positive and false negative results are possible with the newborn screening test for CF. The sweat test will help to determine the diagnosis of CF.

Preparation for the Sweat Test

There are no restrictions on activity or diet or special preparation before the test. However, one should not apply creams or lotions to the skin 24 hours before the test. All regular feedings and medications may be continued and will have no effect on the test results.

Sweat Test Results

Our CF Center experts and genetic counselors will meet with your family to discuss the diagnostic test results and any next steps on the same day. If a CF diagnosis is confirmed, our team will provide educational information about CF, as well as guidance on how to find a CF specialist.

If your child does not have CF but is found to be a carrier of the CF gene, our genetic counselors will provide information about being an unaffected carrier.

Schedule an Appointment for a Sweat Test & Genetic Counseling

If your child has had a positive newborn screening test for CF, please contact one of our CF counselors in the Department of Human Genetics at 773-834-9110 or the UChicago Medicine Cystic Fibrosis Center office at 773-702-6178 to schedule an appointment for further testing and genetic counseling.

At our Cystic Fibrosis Center, we offer a variety of diagnostic tests that enable us to identify CF and monitor its progression.

Sweat Testing

Sweat tests measure the amount of salt in sweat and can diagnose CF, as a high salt level confirms that an individual has CF.

Lung Function Tests

Our pulmonary function laboratory offers a range of tests that measure lung function. Some of the tests available include:

• Spirometry, which measures the volume and speed of air moving out of your child's lungs
• Pulse oximetry and arterial blood gas testing for measuring oxygen in your child's blood

Other Tests

Our team may recommend other tests, such as:

• Chest X-rays
• Sputum cultures to check for bacteria in sputum (mucus from the lungs) that can be signs of advanced CF
• High-resolution computed tomography (CT) to inspect the airways for progression of CF

Genetic Testing & Counseling

Our team can help coordinate prenatal screening to determine if your fetus has CF. We also offer genetic testing to determine if you or your partner carries the genetic mutations that cause CF. Our genetic counselors are available to answer questions and assist you and your family along the way.

When is CF typically diagnosed?

Today, CF is usually diagnosed at birth through newborn screening, with more than 75 percent of patients diagnosed by the age of 2. The sweat test measures salt in a child’s sweat and can confirm the diagnosis.

CF runs in my family. Should I get tested?

CF is a genetic disease. A genetic test can determine if you carry the genetic mutation that causes it. To have CF, a child must inherit the genetic mutation from both parents. People who inherit the mutation from only one parent are called carriers and do not have CF. If you may be a carrier, you and your partner should consider getting a genetic test.

How is CF treated?

Treating CF requires therapies that target parts of the body, especially the lungs and the digestive system. Because CF symptoms can differ widely from child to child, there is no typical treatment plan for children with the disease.

We work closely with CF patients and their families to create individualized treatment plans. Typical therapy often includes: airway clearance to help loosen airway mucus, inhaled medicines, pancreatic enzyme supplement capsules and multivitamins.

There is ongoing research through the Cystic Fibrosis Foundation to find additional therapies that could help improve key symptoms of CF by targeting the disease at its root.

What is the outlook for my child with CF?

Although there is no cure for CF, the outlook for patients with this lung disease is better than ever. According to the Cystic Fibrosis Foundation, the median survival for people with CF is in the early 40s. Many patients live into their 50s and 60s and are able to lead full lives that include work, family and other pursuits.

Is it OK for my child to exercise?

In general, physical activity is good for children with CF because it helps them improve their lung function and clears mucus from the airways.

What are my responsibilities as a parent?

You play a pivotal role on your child’s care team. To make sure your child receives the best care:

• Bring a list of your child’s medications to each visit, and tell us if you need refills
• Let us know if are having insurance issues
• If you do not understand something, please ask
• Tell us if you have any concerns about your child’s treatment plan