Newborn Metabolic Screening Program
Galactosemia
(GALT)
What
Is It?
Galactosemia is a hereditary disease that is caused by the lack
of a liver enzyme required to digest galactose. Galactose is a
breakdown product of lactose, which is most commonly found in
milk products. Since galactose cannot be broken down, it builds
up in the cells and becomes toxic. The body then produces abnormal
chemicals, which causes the symptoms seen in infants with untreated
galactosemia.
Inheritance
and Frequency
The gene defect for Galactosemia is an autosomal recessive genetic
trait and is unknowingly passed down from generation to generation.
This faulty gene only emerges when two carriers have children
together and pass it to their offspring. For each pregnancy
of two such carriers, there is a 25% chance that the child will
be born with the disease and a 50% chance the child will be
a carrier for the gene defect. Incidence is approximately 1in
50,000 births.
Signs
and Symptoms
Galactosemia usually causes no symptoms at birth, but jaundice,
diarrhea, and vomiting soon develop and the baby fails to gain
weight. If not detected immediately, it results in liver disease,
cataracts, mental retardation, and even death. Children suspected
to have galactosemia, whether clinically diagnosed or have a
positive newborn screening (NBS) result showing Galactosemia,
should have a sepsis work up. Ingestion of galactose, whether
through regular formula or breast milk, can produce sepsis in
an affected child. Antibiotics are commonly prescribed for all
galactosemic children who have ingested galactose to prevent
sepsis. Even after a galactosemic child has been switched to
a soy based formula, sepsis can still develop if the child has
previously ingested galactose.
Long
Term Effects
As galactosemic children get older they may encounter delays
in speech and females may suffer from ovarian failure. Nevertheless,
children who are diagnosed early have very good long-term outlooks
and will lead normal, healthy lives.
Treatment
Treatment for galactosemia is the elimination of galactose and
lactose from the diet throughout life. A person with galactosemia
will never be able to properly digest foods containing galactose.
There is no chemical or drug substitute for the missing enzyme
at this time. An infant diagnosed with galactosemia will simply
be changed to a soy-based formula that does not contain galactose.
Galactosemia is often confused with lactose intolerance, but
please keep in mind that galactosemia is a disease. A person
with galactosemia is not someone who had galactosemia as a child
and then grew out of it.