Phenylketonuria (pku)

Phenylketonuria (PKU) is a rare genetic condition in which the body cannot break down an amino acid called phenylalanine (say "fehn-uhl-AL-uh-neen"), which is a part of protein. This substance is found in breast milk, many types of baby formula, and most foods, especially those with a lot of protein, such as meat, eggs, and dairy products. If PKU is not treated, phenylalanine can build up in the blood and lead to intellectual disability and problems with the central nervous system (brain and spinal cord).

Early treatment can help prevent most problems. Babies born with PKU need to start treatment soon after birth.

If phenylketonuria (PKU) is not found and treated soon after birth, symptoms usually start to appear within a few months after birth. (It takes time for the phenylalanine to build up in the baby's body.)

Early symptoms of PKU in a baby may include:

• A musty odor to the skin, hair, and urine.
• Skin problems.
• Being sensitive to light.

Without early treatment, the child may have growth problems, developmental delays, seizures, and severe intellectual disability.

Screening is recommended for all newborns within a few days after birth.

If the phenylketonuria (PKU) screening test shows that your baby has a phenylalanine problem, the doctor will do further testing to check whether your baby has PKU.

Finding and starting treatment for PKU early usually can prevent brain damage and other long-term problems.