How is Cystic Fibrosis Diagnosed

Diagnosis of Cystic Fibrosis

The diagnosis of Cystic Fibrosis (CF) is most frequently made after positive newborn screening for CF.  However, some people with CF are diagnosed as adults. For those who are not diagnosed as infants, the diagnosis is usually made after the primary care practionerhas concerns regarding signs and symptoms that may be suggestive of cystic fibrosis. These symptoms may include:

  • Very salty-tasting skin
  • Persistent coughing, at times with phlegm
  • Frequent lung infections, such as pneumonia or bronchitis
  • Wheezing or shortness of breath
  • Poor growth or poor weight gain in spite of a good appetite
  • Frequent greasy, bulky stools or difficulty in bowel movements
  • Small, fleshy growths in the nose, called nasal polyps
  • Chronic sinus infections
  • Clubbing or enlargement of the fingertips and toes
  • Rectal prolapse (when the rectum sticks out through the anus)
  • Male infertility

The practitioner then refers the child to a Cystic Fibrosis Foundation (CFF) accredited lab for a sweat chloride test or to a CFF accredited care Center where evaluation and testing can be completed. A diagnosis of CF is possible when there are positive signs and symptoms of the disease, or a positive family history and a test that confirms the diagnosis of cystic fibrosis.

Sweat Test

The usual test for CF is a sweat test. This test is done at a special lab and involves a skin test which measures the amount of chloride (one of the body’s natural salts) in a collection of sweat. The test starts with the application of a chemical called pilocarpine to the skin, followed by a small electrical current that stimulates the sweat glands. The sweat is then collected and measured. Persons with cystic fibrosis have elevated or high levels of chloride in the sweat. This test takes about an hour to complete and the results are usually available the same day.

Genetic Testing

Another  way to diagnose CF is to send a blood sample to check for the exact genes involved in CF. This test is more expensive and may miss some patients because of the many different gene mutations that can cause CF.as well as the inability to test for all of these different mutations in a single conventional test. Genetic testing is usually ordered when the sweat chloride test is unable to give an accurate result, or after diagnosis of CF occurs so that certain genotype-specific therapies for CF can be considered

Did you know?

The clinic is moving locations this summer. Stay tuned for more information!

Did you know?

We hold monthly meetings during the school year with our Patient and Family Advisory Board (PFAB). We work on issues and ways to improve CF patient care in the clinic and in the hospital

Testing for CF

Diagnosing CF is a multistep process. A complete diagnostic evaluation should include a newborn screening, a sweat chloride test, a genetic or carrier test and a clinical evaluation at a CF Foundation – accredited care center.

Did you know?

Our center puts on free education days every other year to help educate hospital staff and anyone in the community about CF

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Our center is moving locations in the spring of 2018! Stay tuned…

Did you know?

Many Cystic Fibrosis patients and families face complicated issues related to getting the care they need. But CF Foundation Compass, a service formerly known as PARC, makes sure no one has to do it alone.

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For the first time, adults outnumber children in the CF Registry.  50.7% of people in the registry are over the age of 18.

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We have a Facebook page, too! https://www.facebook.com/cysticfibrosisidaho/

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Idaho is now screening for a handful of CF mutations on the newborn screening.

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You can have your picture scrolling at the top! Just e-mail one you would like us to add and sign a photo release form

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Patient education nutrition recipes: add: For more recipes, check out our Facebook page https://www.facebook.com/cysticfibrosisidaho/