What is a Newborn Screening for Cystic Fibrosis?
My Baby had a Positive Newborn Screen for CF:
It is important to know that most babies who screen positive for cystic fibrosis (CF) do not have it.
Before you took your newborn baby home from the hospital, a small amount of blood was taken from his or her foot as part of Ohio’s Newborn Screening Program. One of your baby’s test results showed a need for a second test called a sweat test.
If you had a negative CF blood test when you were pregnant, but your baby’s newborn screening was positive for CF, your baby should still have a sweat test. The CF carrier testing available to parents during pregnancy cannot rule out the possibility that their baby could have CF.
Why does my baby need a sweat test?
This test is the best way of checking for cystic fibrosis (CF). Babies with CF typically have saltier sweat than normal. The sweat test will measure how much salt is in your baby’s sweat.
Most babies (about 90%) who get a sweat test do not have CF, but it is important to make sure. However, if CF is diagnosed, we know that early treatment by CF specialists is very beneficial.
The sweat test: what to expect
The sweat test takes about one hour from start to finish.
A special machine causes a small part of the baby’s arm or leg to sweat. The skin may feel warm and tingly for five minutes while the machine is on. Your baby may cry during this part of the test, but it is not painful. Sometimes, this process can cause skin irritation on the baby’s skin, but not usually. The sweat is collected on a special coil. After 30 minutes, the coil is removed, and the sweat is tested in the lab.