Cystic Fibrosis Diagnosis
Your doctor may also do the following tests to understand more about your condition and how to treat it:
- Blood tests to look for an abnormal cystic fibrosis gene or other things that can confirm the diagnosis.
- A chest x-ray takes a picture of your lungs and can show scarring from inflammation.
- A sinus x-ray may show signs of sinusitis.
- Lung function tests can measure:
- How much air your lungs can hold
- How quickly you can breathe air out of your lungs
- How well your lungs add oxygen to and remove carbon dioxide from your blood.
- Doctors take a sample of your sputum (phlegm) to see what bacteria are growing in it.
If you are pregnant, prenatal genetic tests can find out if your baby has cystic fibrosis:
- In amniocentesis, your doctor inserts a hollow needle through your abdominal wall into your uterus to obtain cells from the fluid (amniotic fluid) around the baby. The fluid is then tested to see if both of the baby's CFTR genes are normal.
- In a chorionic villus biopsy, your doctor uses an ultrasound to guide a thin tube through your vagina and cervix into your uterus and remove a tiny piece of the placenta to biopsy. The cells of the placenta are then tested to see if the baby has cystic fibrosis.
Some states are now testing the blood of all newborns for CF.
(Click Prenatal Testing for Cystic Fibrosis for more information.)