1. Health
You can opt-out at any time. Please refer to our privacy policy for contact information.

Galactosemia

Pediatric Basics

By

Updated June 11, 2014

Galactosemia is a rare inherited disorder in which children are unable to break down and use the sugar galactose.

Although many parents have never heard of galactose, it is actually a very common sugar, as together with glucose, it makes up lactose. Most parents have heard of lactose, the sugar found in breast milk, cow's milk, and other forms of animal milk, including goat's milk.

Galactose is broken down in the body by the enzyme galactose-1-phosphate uridyltransferase (GALT). Without GALT, galactose and breakdown products of galactose, including galactose-1-phosphate, galactitol, and galactonate build up and become toxic inside cells.

Galactosemia Symptoms

If given milk or milk products, a newborn or infant with galactosemia can develop signs and symptoms that include:

  • poor feeding
  • vomiting
  • jaundice
  • poor weight gain
  • failure to regain birth weight, which usually happens by the time a newborn is two weeks old
  • lethargy
  • irritability
  • seizures
  • cataracts
  • an enlarged liver (hepatomegaly)
  • low blood sugar (hypoglycemia)

For a newborn with classic galactosemia, these symptoms may begin within days of starting to breastfeed or drink a cow's milk based baby formula. Fortunately, these early galactosemia symptoms usually go away once the child is started on a galactose-free diet if the diagnosis is made early.

Diagnosis of Galactosemia

Most children with galactosemia are diagnosed before they develop many galactosemia symptoms because the condition is picked up on newborn screening tests that are done when the child is born. All 50 states in the U.S. test newborns for galactosemia.

If galactosemia is suspected based on a newborn screening test, confirmatory testing for levels of galactose-1-phosphate (gal-1-p) and galactose-1-phosphate uridyltransferase (GALT) will be done and if the infant has galactosemia:

  • gal-1-p will be high and GALT will be very low

Galactosemia may also be diagnosed prenatally using chorionic villus biopsy or amniocentesis tests.

Children who are not diagnosed by a newborn screening tests and are having symptoms might be suspected of having galactosemia if they have something known as "reducing substances" in their urine.

Galactosemia Types

There are actually two types of galactosemia, depending on a child's level of GALT.

Children can have either:

  • classic galactosemia - with a complete or near complete deficiency of GALT
  • partial or variant galactosemia - with a partial GALT deficiency

Unlike infants with classic galactosemia, infants with variant galactosemia, including the Duarte variant, usually don't have any symptoms.

Galactosemia Treatments

There is no cure for classic galactosemia, instead children are treated with a special galactose-free diet in which they avoid all milk and milk-containing products as much as possible for the rest of their life, including:

  • breastmilk
  • cow's milk based baby formula
  • cow's milk, goat's milk, or dry milk
  • margarine, butter, cheese, ice cream, milk chocolate, or yogurt
  • foods that list nonfat dry milk solids, casein, sodium caseinate, whey, whey solids, curds, lactose, or galactose on the list of ingredients

Instead, newborns and infants should drink a soy-based baby formula, such as Enfamil Prosobee Lipil, Similac Isomil Advance, or Nestle Good Start Soy Plus, etc. If your baby doesn't tolerate a soy formula, an elemental formula, such as Nutramigen or Alimentum may be used instead, although they do have small amounts of galactose.

Older children can drink a milk substitute made of isolated soy protein (Vitamite), or a rice drink (Rice Dream).

Children with galactosemia will also have to avoid other foods that are high in galactose, including liver, some fruits and vegetables, and certain dried beans, especially garbanzo beans. A registered dietitian or pediatric metabolic specialist can help you figure out which foods to avoid if your child has galactosemia and to help you make sure your child is getting enough calcium and other important minerals and vitamins.

Gal-1-p levels can be followed to see if a child's diet has too much galactose in it.

The dietary restriction of children with variant galactosemia are more controversial. One protocol involves restricting milk and milk-containing products, including breastmilk, for the first year of life, and then allowing some galactose in the diet once the child is a year old. Another option is to allow an unrestricted diet and watch for an elevation of gal-1-p levels. Although it seems like research is still being done to see which option is best, parents may be reassured that one small study did show that clinical and developmental outcomes up to one year were good in children with Duarte variant galactosemia, both in those who practiced dietary restriction and those who didn't.

What You Need To Know

  • Children with galactosemia or suspected galactosemia are usually treated by a pediatric metabolic specialist.

  • Galactosemia occurs in about 1 in 65,000 births in the United States.

  • Since galactosemia is an autosomal recessive disorder, if two parents are carriers for galactosemia, they will have a 25% chance of having a child with galactosemia, a 50% chance of have a child who is a carrier for galactosemia, and a 25% chance of having a child without any of the genes for galactosemia. Parents of a child with galactosemia will usually be offered genetic counseling if they plan to have more children.

  • Untreated newborns with galactosemia are at increased risk for E. coli septicemia, a life-threatening blood infection.

  • Children with classic galactosemia can also sometimes, even when they follow a strict diet, be at risk for short stature, learning disabilities, gait and balance problems, tremors, speech and language disorders, and premature ovarian failure.


Sources:

Ficicioglu, C. Duarte (DG) galactosemia: a pilot study of biochemical and neurodevelopmental assessment in children detected by newborn screening. Mol Genet Metab - 01-DEC-2008; 95(4): 206-12.

Kliegman: Nelson Textbook of Pediatrics, 18th ed.

Ridel, KR. An updated review of the long-term neurological effects of galactosemia. Pediatr Neurol - 01-SEP-2005; 33(3): 153-61.

©2014 About.com. All rights reserved.

We comply with the HONcode standard
for trustworthy health
information: verify here.