When is pku test done

To have the disease, you must inherit the gene from each parent. The blood sample for PKU is usually taken from your baby's heel called a heel stick. The test is done in the first few days after birth, as early as 24 hours after birth. The test may be repeated within the first week or two after birth. A phenylketonuria PKU screening test is done to see whether a newborn baby has the enzyme needed to use phenylalanine in his or her body.

If this test shows that your baby has a phenylalanine problem, the doctor will do further testing to check whether your baby has PKU. It's important for your baby to have this screening test soon after birth. If a baby has PKU and treatment starts right away, problems such as brain damage are less likely to occur.

Your baby's heel is cleaned with alcohol, and then the heel is poked with a small needle. Several drops of blood are collected inside circles on a special piece of paper. When enough blood has been collected, a small bandage is put on the site. A phenylketonuria PKU test is done to check whether a new baby has the enzyme needed to use phenylalanine in his or her body. If the heel stick screening test shows high phenylalanine levels, a blood sample is taken from your baby's vein to confirm whether he or she has PKU.

Author: Healthwise Staff. This information does not replace the advice of a doctor. Healthwise, Incorporated, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content. Your doctor is likely to ask you several questions. Be ready to answer them to reserve time to go over points you want to focus on.

For example, your doctor may ask:. Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission. This content does not have an English version. This content does not have an Arabic version. Diagnosis Newborn blood testing identifies almost all cases of phenylketonuria. More Information Genetic testing. Email address. First Name let us know your preferred name.

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Genetics Home Reference. Accessed Oct. National Organization for Rare Disorders. Learning about phenylketonuria PKU. National Human Genome Research Institute. Prenatal screening can tell you your chance of having a baby with birth defects. The tests can consist of one or more blood tests and ultrasound. These tests are ordered by your health care provider and can be done at any hospital or laboratory.

During the first few days after birth, your baby will have a newborn screening test, which includes a blood test and examination by a doctor or midwife.

Early detection and treatment of some disorders can help prevent severe mental handicap, growth problems, health problems, or even sudden infant death. A phenylketonuria PKU test is done to check whether a newborn baby has the enzyme needed to use phenylalanine in his or her body. Phenylalanine is an amino acid that is needed for normal growth and development. If a baby's body does not have the enzyme that changes phenylalanine into another amino acid called tyrosine, the phenylalanine level builds up in the baby's blood and can cause brain damage, seizures, and intellectual disability.

The damage caused by PKU can begin weeks after the baby has started drinking breast milk or formula. Babies with PKU need foods low in phenylalanine to prevent severe brain damage.

Phenylalanine is found in most foods that have protein, such as milk, cheese, and meats. It is important to find this disease early. To have the disease, you must inherit the gene from each parent. The blood sample for PKU is usually taken from your baby's heel called a heel stick.

The test is done in the first few days after birth, as early as 24 hours after birth. In some areas, the test may be repeated within the first week or two after birth. A phenylketonuria PKU screening test is done to see whether a newborn baby has the enzyme needed to use phenylalanine in his or her body. If this test shows that your baby has a phenylalanine problem, the doctor will do further testing to check whether your baby has PKU. It's important for your baby to have this screening test soon after birth.

For a child to get the disorder, both the mother and father must pass down a mutated PKU gene. A PKU test is used to see if a newborn has high levels of Phe in the blood. This may mean the baby has PKU, and more tests will be ordered to confirm or rule out a diagnosis. A PKU test is usually part of a series of tests called a newborn screening. A health care provider will clean your baby's heel with alcohol and poke the heel with a small needle.

The provider will collect a few drops of blood and put a bandage on the site. The test should be done no sooner than 24 hours after birth, to ensure the baby has taken in some protein, either from breast milk or formula.

This will help ensure the results are accurate. But the test should be done between 24—72 hours after birth to prevent possible PKU complications. If your baby wasn't born in the hospital or if you left the hospital early, be sure to talk to your child's health care provider to schedule a PKU test as soon as possible. There is very little risk to your baby with a needle stick test. Your baby may feel a little pinch when the heel is poked, and a small bruise may form at the site.

This should go away quickly.