Question

At what time window after birth should newborn screening for PKU be performed?

Options

• Within 2 weeks of birth

• Within 24–48 hours of birth

• Within 1 week of birth

• Within 7 days of birth

Answer 1

Newborn screening for PKU (using Guthrie test or Tandem Mass Spectrometry) must be performed within 24–48 hours of birth. Early detection allows for immediate dietary intervention with a phenylalanine-restricted diet, preventing mental retardation and other severe complications.