Galaktózémia

Galaktózémia is a group of inherited metabolic disorders caused by deficient activity of one of the enzymes needed to metabolize galactose, a sugar obtained from lactose in dairy products. The most common and severe form is classic galactosemia, due to mutations in the GALT gene, which leads to accumulation of galactose-1-phosphate and other metabolites in liver, kidney and brain. Less common are galactokinase deficiency (GALK1), which mainly causes cataracts, and GALE deficiency (UDP-galactose-4-epimerase). The Duarte variant refers to a partial GALT deficiency with a milder presentation.

Genetically, galactosemia is typically inherited in an autosomal recessive manner. The clinical picture depends on the form: classic galactosemia often presents in the newborn period after starting milk feeding with vomiting, poor feeding, jaundice, hepatomegaly, hypoglycemia, and increased risk of sepsis; long-term complications can include developmental delay, motor difficulties, speech problems, and ovarian insufficiency in females. Galactokinase deficiency presents mainly with early cataracts, while GALE deficiency shows a broader but variable spectrum of symptoms, from mild to severe.

Diagnosis is supported by newborn screening in many regions and confirmed by tests such as measurement of galactose-1-phosphate or GALT enzyme activity, and genetic testing. Management requires lifelong restriction of lactose and galactose-containing foods and formulas, along with regular monitoring for growth, development, liver and kidney function, and reproductive health in females.

Prognosis improves with early detection and dietary management, though some individuals may still experience neurodevelopmental or reproductive challenges.