Galactose Metabolism

These flashcards cover the key elements of galactose metabolism, the implications of galactosemia, and necessary treatments.

What is galactose primarily ingested as?

Lactose, which is a disaccharide of galactose and glucose.

What enzyme phosphorylates galactose to galactose 1-phosphate?

Galactokinase.

What is the role of galactose 1-phosphate in metabolism?

It can be activated to UDP glucose for glycogen synthesis or converted to glucose 1-phosphate.

What enzyme is responsible for converting galactose 1-phosphate to UDP glucose?

Galactose 1-phosphate uridyl transferase (GALT).

What condition results from a deficiency in GALT?

Classic galactosemia.

What are potential consequences of classic galactosemia?

Elevated galactose 1-phosphate leads to inhibition of hepatic glycogen metabolism, cataracts, and can be toxic to the liver, kidneys, and central nervous system.

When do symptoms of classic galactosemia typically present?

Very early, as infants on lactose from milk, especially within the first few days of life.

How is classic galactosemia detected?

Through determination of GALT activity as part of the newborn screening process.

What dietary change is made for infants diagnosed with classic galactosemia?

They are placed on a lactose-free formula.

Why is it crucial to obtain GALT activity results promptly in newborns?

Children with classical galactosemia can have life-threatening crises within the first few days.