Problems with the new born screen for galactosaemia

Area of Science:

• Biochemistry
• Genetics
• Pediatrics

Background:

• Newborn screening aims to detect serious genetic disorders in asymptomatic infants before irreversible damage occurs.
• Classical galactosaemia is a severe inherited metabolic disorder that can lead to liver failure and other complications if not identified early.

Observation:

• A family experienced two children with classical galactosaemia, with the first child missed by newborn screening, leading to liver failure and transplant.
• The second child presented with similar symptoms but was identified by newborn screening due to reduced galactose-1-phosphate uridyl transferase activity.

Findings:

• Early detection through newborn screening and immediate dietary intervention (lactose and galactose restriction) led to significant clinical improvement in the second child.
• A critical factor in screening accuracy involves ensuring the patient has only native red blood cells when measuring enzyme activity for inborn genetic defects.

Implications:

• This case highlights the importance of robust newborn screening programs for identifying classical galactosaemia.
• Physicians must be aware of potential screening test failures, particularly concerning red blood cell integrity, to prevent diagnostic errors and ensure timely treatment.