Doctors diagnose cystic fibrosis (CF) based on the results from various tests.
All States screen newborns for CF using a genetic test or a blood test. The genetic test shows whether a newborn has faulty CFTR genes. The blood test shows whether a newborn's pancreas is working properly.
If a genetic test or blood test suggests CF, a doctor will confirm the diagnosis using a sweat test. This test is the most useful test for diagnosing CF. A sweat test measures the amount of salt in sweat.
For this test, the doctor triggers sweating on a small patch of skin on an arm or leg. He or she rubs the skin with a sweat-producing chemical and then uses an electrode to provide a mild electrical current. This may cause a tingling or warm feeling.
Sweat is collected on a pad or paper and then analyzed. The sweat test usually is done twice. High salt levels confirm a diagnosis of CF.
If you or your child has CF, your doctor may recommend other tests, such as:
If you're pregnant, prenatal genetic tests can show whether your fetus has CF. These tests include amniocentesis (AM-ne-o-sen-TE-sis) and chorionic villus (ko-re-ON-ik VIL-us) sampling (CVS).
In amniocentesis, your doctor inserts a hollow needle through your abdominal wall into your uterus. He or she removes a small amount of fluid from the sac around the baby. The fluid is tested to see whether both of the baby's CFTR genes are normal.
In CVS, your doctor threads a thin tube through the vagina and cervix to the placenta. The doctor removes a tissue sample from the placenta using gentle suction. The sample is tested to see whether the baby has CF.
People who have one normal CFTR gene and one faulty CFTR gene are CF carriers. CF carriers usually have no symptoms of CF and live normal lives. However, carriers can pass faulty CFTR genes on to their children.
If you have a family history of CF or a partner who has CF (or a family history of it) and you're planning a pregnancy, you may want to find out whether you're a CF carrier.
A genetics counselor can test a blood or saliva sample to find out whether you have a faulty CF gene. This type of testing can detect faulty CF genes in 9 out of
Clinical trials are research studies that explore whether a medical strategy, treatment, or device is safe and effective for humans. To find clinical trials that are currently underway for Cystic Fibrosis, visit www.clinicaltrials.gov.
Visit Children and Clinical Studies to hear experts, parents, and children talk about their experiences with clinical research.
November 20, 2013
Gary H. Gibbons
New NHLBI Program Trains Scientists to Bring More Science Out of the Lab and into the Patient Care Marketplace
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