A rare genetic disorder known as galactosemia affects how a sugar is broken down in the body. Milk and dairy products, fruits and vegetables contain galactose. A person with galactosemia cannot convert galactose into glucose, which is the body's main source of energy. As a result, galactose and its byproducts can build up in the blood and tissues, leading to serious health problems.
As galactosemia is inherited in an autosomal recessive pattern, both parents must pass on a defective gene to the child. There are three main types of galactosemia, depending on the enzyme that is missing or defective:
Approximately 1 in 30,000 to 60,000 people worldwide suffer from classic galactosemia (type I), caused by a deficiency of the enzyme galactose-1-phosphate uridylyltransferase (GALT).
Galactokinase deficiency (type II): A milder form, caused by a deficiency of the enzyme galactokinase (GALK). This affects about 1 in 360,000 people worldwide.
About 1 in 360,000 people worldwide suffer from galactokinase deficiency (type II), a milder form caused by a lack of the enzyme galactokinase (GALK). 1 in 1,000,000 people worldwide.
ThIt affects about 1 in 1,000,000 people worldwide due to a deficiency of the enzyme UDP-galactose-4'-epimerase (GALE).eks of life, after the baby starts to consume breast milk or formula that contains lactose (a sugar composed of galactose and glucose). Some of the common symptoms include:
Poor appetite and feeding difficulties
Vomiting and diarrhea
Jaundice (yellowing of the skin and eyes)
Lethargy and irritability
Failure to thrive and grow
Enlarged liver and spleen
Bleeding and bruising
Infections and sepsis
Cataracts (clouding of the lens of the eye)
Developmental delays and intellectual disabilities
Speech and language problems
Motor and coordination difficulties
Hormonal imbalances and infertility
Several inherited disorders are diagnosed through newborn screening, which is a blood test. The test measures the levels of galactose and its byproducts in the blood, as well as the activity of the enzymes involved in galactose metabolism. If the screening test is positive, a confirmatory test is performed to identify the specific type and mutation of galactosemia. This may include both blood and urine samples, as well as genetic testing.
The main treatment for galactosemia is a lifelong diet that restricts or eliminates galactose and lactose. This means avoiding milk and dairy products, as well as foods that contain galactose or lactose as ingredients or additives. Those with galactosemia should also avoid fruits and vegetables that have high amounts of galactose. They should read food labels carefully and consult a dietitian for guidance.
In addition to dietary management, people with galactosemia may need other treatments to prevent or treat the complications of the condition. These may include:
Supplements of calcium, vitamin D, and other nutrients to prevent bone loss and fractures
Medications to treat infections, bleeding, liver problems, and hormonal imbalances
Surgery to remove cataracts or correct other eye problems
Physical, occupational, and speech therapy to improve motor, cognitive, and language skills
Psychological and social support to cope with the emotional and social challenges of living with a chronic condition
Newborn screening is the best way to identify babies with galactosemia and start them on a proper diet as soon as possible. Galactosemia cannot be prevented, but it can be detected early and treated effectively. By doing so, serious and irreversible organ and tissue damage can be prevented or reduced.
The genetic counseling and testing process can also help parents with a family history of galactosemia or who carry the faulty gene. This can help them understand the chances of having a child with galactosemia and the options available for prenatal diagnosis and treatment.
