Diagnosis & Tests

Tests can be carried out to diagnose cystic fibrosis at any age.

Cystic Fibrosis

Tests can be carried out to diagnose Cystic Fibrosis at any age.

Most cases are now detected soon after birth through newborn screening, but older children and adults with symptoms of cystic fibrosis who weren't screened can also have tests to check for the condition.

Tests to find out if you are a "carrier" of the faulty gene responsible for Cystic Fibrosis may also be recommended for some people.

Newborn Screening

A newborn blood spot test is now offered to all babies in England to help detect problems early on, including cystic fibrosis.

When your baby is five to eight days old, a health professional will prick their heel and collect drops of blood on a special card. The blood is then sent to a laboratory to be checked for abnormalities that could indicate cystic fibrosis.

You should receive the results by the time your baby is six to eight weeks old. You will be contacted sooner if a problem is found, and you'll be asked to attend a hospital appointment.

The screening result isn't 100% accurate, so more tests will be carried out to confirm the diagnosis. You, your partner and any other children you have may also be tested to see if you carry the faulty gene that causes cystic fibrosis (see below).

Carrier Testing

Testing to find out if you carry the faulty gene that causes cystic fibrosis may be useful if:

  • You have a close relative, such as a child, sibling or parent, who's a known carrier.
  • You have a close relative with cystic fibrosis.
  • Your partner is known to carry the cystic fibrosis gene.

This can be done using a blood test, or occasionally a special mouthwash, to collect a sample of cells. The sample is then sent to a laboratory so it can be checked for the faulty gene.

Finding out whether you're a carrier of the faulty gene can help determine if you're at risk of having a child with cystic fibrosis.  A genetic counsellor will explain the results of the test to you and discuss the implications and options available for future pregnancies.