NLST - Phenylketonuria (PKU)

Phenylketonuria (PKU)

An inborn error of metabolism resulting in decreased metabolism of phenylalanine

Phenylalanine Hydroxylase (PAH)

The enzyme that is deficient in PKU

Tyrosine

The amino acid that phenylalanine normally converts into, which becomes conditionally essential in PKU

Dopamine & Norepinephrine

Two neurotransmitters that tyrosine helps produce, which are reduced in untreated PKU

Melanin

The pigment whose production is decreased in PKU, leading to fair skin and hair

Musty or Mousy

The characteristic body and urine odor of an untreated PKU patient

Heel prick test

The common name for the newborn screening used to diagnose PKU

>6 mg/dL

The blood phenylalanine level indicative of PKU, compared to the normal 1-2 mg/dL

120-360 umol/L

The goal range for maintaining safe blood phenylalanine levels in children

200-500 mg/day

The typical daily intake limit for phenylalanine, though it is individualized

Aspartame

An artificial sweetener that must be strictly avoided by PKU patients because it contains phenylalanine

Sapropterin (BH4)

An adjunct treatment that enhances enzyme activity in some responsive PKU cases