Galactosemia is a rare genetic disorder that affects how your body metabolizes galactose. Galactose is a simple sugar found in milk, cheese, yogurt, and other dairy products. When it’s combined with glucose, it makes lactose.

Galactosemia means having too much galactose in the blood. The buildup of galactose can lead to serious complications and health problems.

There are four main types of galactosemia disorders:

  • type 1, or classic and clinical variant galactosemia
  • type 2, or galactokinase deficiency
  • type 3, or epimerase deficiency
  • Duarte variant galactosemia

Read on to learn more about this condition.

Symptoms

Symptoms of galactosemia usually develop several days or weeks after birth. The most common symptoms include:

  • loss of appetite
  • vomiting
  • jaundice, which is yellowing of the skin and other parts of the body
  • liver enlargement
  • liver damage
  • fluid building up in the abdomen and swelling
  • abnormal bleeding
  • diarrhea
  • irritability
  • fatigue or lethargy
  • weight loss
  • weakness
  • higher risk of infection

Babies who have galactosemia have problems eating and tend to lose weight. This is also known as failure to thrive. Learn more about what failure to thrive means for your child.

Complications

Multiple complications can appear if galactosemia isn’t diagnosed and treated right away. The buildup of galactose in the blood can be dangerous. Without diagnosis and intervention, galactosemia can be life-threatening in newborns.

Common complications of galactosemia include:

  • liver damage or liver failure
  • serious bacterial infections
  • sepsis, which is a life-threatening problem caused by infections
  • shock
  • delayed development
  • behavioral problems
  • cataracts
  • tremors
  • speech problems and delays
  • learning disabilities
  • fine motor difficulties
  • low bone mineral density
  • reproductive problems
  • premature ovarian insufficiency

Premature ovarian insufficiency is only seen in women. The ovaries stop functioning at an early age and affect fertility. This usually occurs before the age of 40. Some of the symptoms of premature ovarian insufficiency are similar to menopause.

What causes galactosemia?

Galactosemia is caused by mutations in genes and a deficiency of enzymes. That causes the sugar galactose to build up in the blood. It’s an inherited disorder, and parents can pass it down to their biological children. The parents are considered carriers of this disease.

Galactosemia is a recessive genetic disorder, so two copies of the defective gene have to be inherited for the disease to appear. This usually means a person inherits one defective gene from each parent.

Incidence

Type 1 galactosemia occurs in 1 out of every 30,000 to 60,000 babies. Type 2 galactosemia is less common than type 1 and occurs in 1 out of every 100,000 babies. Type 3 and Duarte variant galactosemia are very rare.

Galactosemia is more common among those who have Irish ancestry and among people of African descent living in the Americas.

Diagnosis

Galactosemia is usually diagnosed though tests that are done as part of newborn screening programs. A blood test will detect high levels of galactose and low levels of enzyme activity. The blood is usually taken by pricking a baby’s heel.

A urine test may also be used to diagnose this condition. Genetic testing can also help diagnose galactosemia.

Treatment

The most common treatment for galactosemia is a low-galactose diet. This means that milk and other foods that contain lactose or galactose can’t be consumed. There is no cure for galactosemia or approved medication to replace the enzymes.

Although a low-galactose diet can prevent or reduce the risk of some complications, it may not stop all of them. In some cases, children still develop problems such as speech delays, learning disabilities, and reproductive issues.

Speech problems and delays are a common complication, so some children may benefit from speech therapy as part of the treatment plan.

In addition, children who have learning disabilities and other delays may benefit from individual education plans and intervention.

Galactosemia can increase the risk of infections, so controlling infections when they occur is crucial. Antibiotic treatments or other medications may be necessary.

Genetic counseling and hormone replacement therapy may also be recommended. Galactosemia can affect puberty, so hormone replacement therapy may help.

It’s important to talk to your doctor and address concerns early.

Diet

To follow a low-galactose diet, avoid foods with lactose, including:

  • milk
  • butter
  • cheese
  • ice cream
  • other dairy products

You can replace many of these foods with dairy-free alternatives, like almond or soy milk, sorbet, or coconut oil. Learn about almond milk for babies and toddlers.

Human breast milk also contains lactose and isn’t recommended for babies diagnosed with this condition. Some babies with Duarte variant galactosemia may still be able to drink breast milk, however. Talk to your doctor if you have any concerns about not being able to breastfeed your baby.

While the Centers for Disease Control and Prevention (CDC) recommends breast milk as the best way for infants to receive nutrients, they don’t recommend breastfeeding an infant with galactosemia. Instead, you’ll need to use a lactose-free formula. Ask your doctor about formula options.

If you plan to use formula, look for a lactose-free version. Many dairy products are fortified with vitamin D. Talk to your doctor about vitamin D supplements and whether they are appropriate for your child.

Outlook

Galactosemia is a rare inherited disorder that affects how galactose is processed in the body. If galactosemia isn’t diagnosed at an early age, then complications can be serious.

Following a low-galactose diet is an essential part of managing this disorder. Talk to your doctor about additional diet restrictions and other concerns.