How It Is Done
Tests for galactosemia are done on a blood or urine sample.
Blood sample from a heel stick
If galactosemia testing is done on a baby, a heel stick will be
done instead of a blood draw from a vein. For a heel stick blood sample,
several drops of blood are collected from the heel of the baby. The skin of the
heel is cleaned with alcohol and then punctured with a sterile lancet. Several
drops of blood are collected inside circles on a specially prepared piece of
paper. When enough blood has been collected, a gauze pad or cotton ball is
placed over the puncture site. Pressure is maintained on the puncture site
briefly to stop the bleeding, and then a small bandage is usually applied. A
blood sample is usually collected within 2 to 3 days after birth.
If the test shows that the baby has galactosemia, the results
will be confirmed on a blood sample taken from a vein.
Blood sample from a vein
The health professional drawing your child's blood will:
- Wrap an elastic band around your child's
upper arm to stop the flow of blood. This makes the veins below the band larger
so it is easier to put a needle into the vein.
- Clean the needle
site with alcohol.
- Put the needle into the vein. More than one
needle stick may be needed.
- Attach a tube to the needle to fill it
with blood.
- Remove the band from your child's arm when enough blood
is collected.
- Apply a gauze pad or cotton ball over the needle site
as the needle is removed.
- Apply pressure to the site and then a
bandage.
Urine sample
To test for galactose in a urine sample from a baby, a health
professional will tape a plastic collection bag to the baby's genital area.
After the baby urinates, the collection bag is removed. A blood test for
galactose is more accurate than a urine test.