苯丙酮酸尿:The inherited inability to metabolize (process) theessentialamino acidphenylalaninedue to complete or near-complete deficiency of the enzyme phenylalanine hydroxylase.
Newborns are screened forphenylketonuria(PKU) by a blood test, usually with the Guthrie card bloodspot obtained from a heelprick.
Treatment is with a special diet low in phenylalanine. The goal is to normalize the levels of phenylalanine andtyrosinein the blood to prevent brain damage. Failure of treatment results in profound irreversiblemental retardation, microcephaly (an abnormally small head),癫痫, and behavior problems. It is clear that if the diet is not followed closely, especially duringchildhood, some impairment is inevitable. Maternal phenylketonuria requires a diet low in phenylalanine.
Phenylketonuria is inherited in anautosomal recessivemanner, as are lesser degrees of phenylalanine hydroxylase deficiency. Phenylketonuria is abbreviated and commonly referred to as PKU.
