Phenylketonuria (PKU): What is PKU and its Treatment

In the United States, each year about 1 in 10,000 to 15,000 babies is born with PKU. This disease occurs in all ethnic groups. But it is most common in Native Americans and northern Europeans in African Americans, or Japanese in Ashkenazi Jews.

What is Phenylketonuria?

Phenylketonuria (PKU for short) is a condition in which the body cannot process an amino acid called phenylalanine. Amino acids help build protein in the body. Without treatment, phenylalanine builds up in the blood and causes health problems.

What causes PKU?

PKU is inherited. That means it is passed from parents to children through genes. The gene is a part of the cells in your body that contains instructions on how your body grows and functions. Genes come in pairs; each person inherits a gene pair’s father, and a gene pair of the mother.

Phenylketonuria (PKU): What is PKU and its Treatment

Sometimes genes can undergoes sudden change. This change is called  “Gene mutation“. Parents can pass the changes in genes to their children. Sometimes change can cause the gene may not function properly. Sometimes it can cause birth defects or other health problems.

The birth defect is a health problem that is present when the baby is born. To have PKU, your child must inherit a change in the gene for PKU from both parents. If you inherit the gene change only one parent has the gene change for PKU, but not has the disease. In that case, she says her baby is a carrier of PKU. The carrier has PKU gene change but not have the disease.

How to tell if your baby has PKU?

All babies are doing screening tests for newborns for Phenylketonuria. Screening for newborns detect conditions in the baby at birth they are rare but serious. These include a blood test, hearing and heart. With screening, PKU can be detected and treated early so babies can grow healthy. Before giving your baby high, the health professional will take a few drops of blood from the heel. The blood is collected in a special paper and sent to a laboratory for analysis. The lab sends the test results to health care for your baby.

If the results are not normal, it simply means that he must do more tests your baby. The health professional may recommend another type of test, called diagnostic test. This test can check if your baby has Phenylketonuria or if abnormal results are due to other causes. If you are doing the test to your baby before their first full day of life, PKU may not be detected. Some experts recommend that if you do the test to your baby within 24 hours of life, the test has to be repeated when 1-2 weeks of age.

Phenylketonuria symptoms:

What problems can cause PKU?

Babies born with Phenylketonuria appear normal the first few months of life. But without treatment, they begin to have signs and symptoms of the disease at about 6 months of age. These include:

Jerky movements of the arms and legs

Skin and eyes lighter color. Infants with PKU cannot adequately produce melanin, the pigment that is responsible for skin colour and hair.

  • Body odor similar to Rust
  • Seizures
  • Skin rashes
  • Small head size
  • Learn to sit, crawl or walk later than planned
  • Loses interest in the surrounding environment
  • Delays in mental and social skills
  • Intellectual disabilities
  • Behavioral problems such as hyperactivity

Phenylketonuria treatment:

If your baby has PKU, what kind of treatment you need?

You may need weekly or more frequent testing during the first year of life to control their phenylalanine levels. After that, you may be get tested once or twice a month during childhood.

Your baby should follow a special meal plan low in phenylalanine. It is best to start this plan as soon as possible, ideally within the first 7-10 days of life. At first, it gives your baby a special formula of protein with reduced phenylalanine. Protein is important to help your baby grow and develop. The amount of phenylalanine of the formula is controlled to meet the individual needs of your baby. It can also give him some milk. Breast milk contains phenylalanine, so talk to the health professional to find out how much your baby breast milk can provide.

When your baby is ready to eat solid foods, you can eat vegetables, fruits, some grains (such as cereals, breads and pasta are low in protein) and other foods low in phenylalanine. If your baby has PKU, you should not eat:

Milk, cheese, ice cream or other dairy products

  • Eggs
  • Meat or poultry
  • Fish
  • Nuts
  • Beans
  • Food or beverages with aspartame, an artificial sweetener that contains much phenylalanine.

Meal plans for PKU are different for each baby and will vary over time depending on the amount of phenylalanine that can process the baby. The health professionals at a medical center or clinic with a special program to treat PKU can help you create a meal plan for your baby. Ask information to professional health of your baby on the medical centers or clinics that treat PKU.

Your child should follow the meal plan for PKU entire life. If in the future your child becomes pregnant, you should follow the meal plan during pregnancy. Most pregnant women with PKU can have healthy pregnancies and babies.

The drug Kuvan (sapropterin dihydrochloride) may help some people with PKU. It is more likely to take effect in people with mild PKU special forms. Children taking Kuvan must follow a special meal plan, but possibly not as strict as those not taking the drug. Anyway, still they need to be frequent blood tests to check levels of phenylalanine.

Source: PKU