Galactose Quantitative Plasma - Test, Procedure & Cost

It is used for screening galactosemia.

Galactosemia: Autosomal recessive disorder

It is an inherited metabolic disorder of carbohydrates that occurs due to a deficiency of 1 of the four enzymes galactose-1-phosphate uridyltransferase, galactokinase, uridine diphosphate galactose-4-epimerase, and galactose mutarotase.

There are four types of galactosemia:

1. Classic galactosemia-due mutation in the GALT gene
2. Galactokinase deficiency-due to a mutation in the GALK gene
3. Galactose epimerase-due to a mutation in the GALE gene
4. Duarte galactosemia-due to a mutation in the GALT gene (same as in classic galactosemia, but less severe mutation)

Incidence: Classic Galactosemia

The GALT enzyme is required for galactose metabolism into simple sugar(glucose). If this enzyme is less, then galactose is not ingested.  It leads to the accumulation of galactose in the body. The increased plasma concentration of galactose which leads to its manifestations-

• Loss of appetite.
• Lethargy.
• Vomiting.
• Diarrhea.
• Severe weight loss.
• Weakness.
• Failure to thrive.
• Jaundice.
• Enlarged liver.
• Abdominal swelling with fluid (ascites).
• Swelling around the brain(edema)

Complications

If galactosemia is not treated at its early stage, it leads to further complications such as liver failure, cirrhosis, intellectual disability, cataract splenomegaly, tremors, shock, learning disability, speech problems and delays, and low bone mineral density. They have an increased risk of Escherichia coli sepsis.

Females affected with galactosemia show premature ovarian insufficiency.

Diagnosis

Newborn screening is done by pricking the baby’s heel to collect blood samples, usually 24 hours after birth. The model is then analyzed, and galt enzyme concentration is measured, which helps diagnose.

Urine tests and genetic testing can also be done for diagnosis.

Galactosemia is diagnosed when there is an increased concentration of galactose-1-phosphate in erythrocytes and  galactose-1-phosphate uridyltransferase deficiency

Treatment

Galactosemia is usually treated by galactose restriction in diet.

Galactose is mainly present in dairy products such as butter, buttermilk, cream, and dairy milk and should be avoided from diet insta soya milk can be consumed. This will reduce the risk of complications.

Vitamin D and calcium supplements are given in the diet to maintain bone density.

The galactose-1-phosphate concentration in erythrocytes is increased, and the GALT enzyme is decreased in case of inefficient diet restriction.