Galactosemia
Galactosemia is a rare, inherited genetic condition caused by high levels of galactose in the blood. Galactose is a part of the sugar (lactose) found in dairy products. Galactosemia is caused by a deficiency in one of the three enzymes needed to break down galactose, so it builds to dangerous levels.
A child who has galactosemia appears normal at birth but develops symptoms after taking formula or breast milk. Symptoms of galactosemia include:
- Loss of appetite.
- Vomiting.
- Diarrhea.
- Poor weight gain.
Without early diagnosis and treatment, a child with galactosemia can develop severe effects. The child may be slow to develop and may have vision problems (cataracts), liver problems, and intellectual disabilities. One form of the disease causes cataracts without intellectual disabilities or poor growth.
Galactosemia is treated with a special diet that does not contain galactose or lactose. A person who has galactosemia must always avoid milk and milk products.
Why is a galactosemia test done?
A galactosemia test is done to:
- Find out whether a newborn has the enzymes needed to change galactose into glucose.
- See whether diet changes are working for a child who has galactosemia.
How is a galactosemia test done?
Tests for galactosemia are done on a blood or urine sample.
Blood sample from a heel stick
A heel stick is used to get a blood sample from a baby. The baby's heel is poked, and several drops of blood are collected. Your baby may have a tiny bruise where the heel was poked.
Blood sample from a vein
A health professional uses a needle to take a blood sample, usually from the arm.
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.
How do you prepare for a galactosemia test?
You don't need to do anything to prepare for this test.
What do the results of a galactosemia test mean?
The results from a galactosemia test may be negative (galactosemia is not present) or positive (galactosemia is present). Or the results may include specific lab values that mean the person has or does not have galactosemia or is a carrier for it.
A newborn screening test that shows that the baby has an increased risk of galactosemia will be confirmed by other tests.
Many conditions can change galactose levels. Your doctor will discuss any significant abnormal results with you in relation to your baby's symptoms and past health.
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