描述
Phenylketonuria (Hyperphenylalaninemia ; HPA ; PKU) is an autosomal recessive genetic disorder characterized by a deficiency in the enzyme hepatic phenylalanine hydroxylase (PAH). PAH is necessary to metabolize the amino acid phenylalanine to the amino acid tyrosine. When PAH is deficient, phenylalanine accumulates and is converted into phenylpyruvate, which is detected in the urine. Left untreated, this condition can cause problems with brain development, leading to progressive mental retardation and seizures.