Galactosemia is a rare, hereditary disorder of carbohydrate metabolism that affects the bodys ability to convert galactose to glucose. Galactose is a sugar found in milk and dairy products, and it is also produced by the human body. Glucose is a different type of sugar. The disorder is caused by a deficiency of an enzyme called galactose-1-phosphate uridylyl transferase (GALT), which is vital to this process. Galactosemia is an autosomal recessive genetic disorder, meaning that an individual must inherit a non-working gene from each parent to be affected by the condition. If an individual receives one working gene and one non-working gene for the disease, they will be a carrier for the disease, but usually will not show symptoms. The risk for two carrier parents to both pass the non-working gene and, therefore, have an affected child is 25% with each pregnancy.
Classic galactosemia is the most common and severe type, and signs usually start in a babys first week of life. Symptoms include poor feeding, vomiting, fussiness or irritability, yellow skin and eyes (jaundice) and a big liver, cataracts (cloudy eye lenses), and blood infections (sepsis). If left untreated, a baby may have trouble growing and gaining weight, and experience slowed development. Galactosemia can also lead to reproductive problems in females, caused by an early loss of function of the ovaries (premature ovarian insufficiency) .
The only known way to treat galactosemia is to eliminate galactose from the diet. This means avoiding milk and dairy products, as well as other foods that contain galactose. Its important to catch the condition early to avoid serious and life-threatening complications. U.S. hospitals screen for the condition at birth, and if diagnosed, dietary modifications are essential to manage the condition and prevent complications.
