Phenylketonuria

Phenylketonuria (PKU) is an autosomal recessive genetic disorder caused by mutations in the phenylalanine hydroxylase gene, leading to deficient enzyme activity and subsequent accumulation of phenylalanine in the blood and tissues. This buildup results in neurotoxic effects, causing severe intellectual disability, developmental delays, seizures, eczema, light-colored skin and hair, and a distinctive musty odor in breath, sweat, or urine if left untreated. PKU affects approximately 1 in 15,000 newborns worldwide and is typically diagnosed through newborn screening. Early detection and strict lifelong management with a low-phenylalanine diet are essential to prevent irreversible neurological damage. Maternal PKU poses significant risks to fetal development, including intellectual disability, congenital heart defects, and low birth weight, underscoring the importance of metabolic control during pregnancy. The condition is part of a broader spectrum of hyperphenylalaninemia disorders, with severity correlating to phenylalanine levels. With proper dietary intervention and regular monitoring, individuals with PKU can achieve normal cognitive development and improved quality of life.

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