Phenylketonuria

Overview

What is phenylketonuria?

Phenylketonuria, or PKU, is a rare genetic disorder. People with this disorder lack a substance in the body called phenylalanine hydroxylase (PAH). This substance is an enzyme needed to break down an amino acid called phenylalanine. Phenylalanine is a 'building block' that we get from our food that is required for proper growth and development. Because people with PKU lack the enzyme PAH, the amino acid, phenylalanine builds up in the blood, brain and other tissues of the body. When phenylalanine builds up, it can damage the body and harm the brain. If untreated, PKU can eventually cause serious problems including intellectual disabilities, seizures, and behavioral problems. The main form of the disorder, classic PKU, is usually identified through newborn screening so treatment is often started before symptoms begin. People get phenylalanine mostly through what they eat. Phenylalanine is found in all foods containing protein and in some artificial sweeteners. PKU is treated by a low-protein diet and the use of Medical Foods (including specialized formulas) that contain very little or no phenylalanine. PKU is caused by changes (alterations) in the PAH gene and is passed on in a family in an autosomal recessive manner. There is a mild form called non-PKU hyperphenylalaninemia. These people have a mild buildup of phenylalanine in the body, but often do not require treatment.

References
  • Mitchell JJ. Phenylalanine Hydroxylase Deficiency. GeneReviews website. Accessed June 5, 2016. http://www.ncbi.nlm.nih.gov/books/NBK1504/
  • Phenylketonuria. Genetics Home Reference website. Accessed June 5, 2016. https://ghr.nlm.nih.gov/condition/phenylketonuria#synonyms
Show More Content Like This

More Overview Content

Are there other names for phenylketonuria?

How is phenylketonuria abbreviated?

What are the subtypes of phenylketonuria?

How common is phenylketonuria?

What is phenylketonuria PKU?

Are there other names for phenylketonuria?

Phenylketonuria is also known as:

  • Classic Phenylketonuria
  • Classical Phenylketonuria
  • Folling Disease
  • PAH Deficiency
  • Phenylalanine Hydroxylase Deficiency
  • PKU
References
  • Phenylketonuria. Online Mendelian Inheritance in Man (OMIM) website. Accessed June 5, 2016. http://www.omim.org/entry/261600
  • Phenylketonuria. The National Organization for Rare Disorders website. Accessed June 5, 2016. http://rarediseases.org/rare-diseases/phenylketonuria/
How is phenylketonuria abbreviated?

The official medical abbreviation for phenylketonuria is PKU.

References
  • Phenylketonuria. Online Mendelian Inheritance in Man (OMIM) website. Accessed June 5, 2016. http://www.omim.org/entry/261600
What are the subtypes of phenylketonuria?

The main form of phenylketonuria (PKU) is known as classic or classical PKU. The majority of people with PKU have the classic form. Some people have a milder form called benign hyperphenylalaninemia or non-PKU hyperphenylalaninemia. These people often do not require treatment. Other people may not fit into ether of these two forms and doctors may say these people have variant PKU.

References
  • Mitchell JJ. Phenylalanine Hydroxylase Deficiency. GeneReviews website. Accessed June 5, 2016. http://www.ncbi.nlm.nih.gov/books/NBK1504/
How common is phenylketonuria?

In the United States, phenylketonuria (PKU) is estimated to affect anywhere from about 1 in 10,000 to 19,000 newborns. Phenylketonuria is more common in certain geographic areas around the world than in others. In some ethnic groups or specific populations, it may occur more often, while in others it may be very rare. PKU affects both boys and girls.

References
  • Phenylketonuria. Genetics Home Reference website. Accessed June 5, 2016. https://ghr.nlm.nih.gov/condition/phenylketonuria#synonyms
  • Blau N. Classic Phenylketonuria. Orphanet website. Accessed June 5, 2016. http://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=EN&Expert=79254
What is phenylketonuria PKU?

Phenylketonuria (PKU) is an inherited disorder that increases the levels of phenylalanine in the blood. Phenylalanine is a building block of proteins (an amino acid) that is obtained through the diet. If PKU is not treated phenylalanine can build up to harmful levels in the body. The signs and symptoms of PKU vary from mild to severe. The most severe form of this disorder is known as classic PKU. Without treatment these children develop permanent intellectual disability. Light skin and hair, seizures, delayed development, behavioral problems and psychiatric disorders are also common. Less severe forms of this condition sometimes called variant PKU and non-PKU hyperphenylalaninemia have a smaller risk of brain damage. Babies born to mothers with PKU and women who no longer follow a low-phenylalanine diet have a risk of intellectual disability and other serious complications because they are exposed to very high levels of phenylalanine before birth. PKU is caused by changes (mutations) in the PAH gene. It is inherited in an autosomal recessive manner. Because PKU can be detected by a simple blood test and is treatable newborn screening is available for this disorder. The best treatment for PKU is low-protein diet and medical foods (including specialized formulas) for life.

We use cookies to ensure that we give you the best experience on our website. By continuing to browse this site, you are agreeing to our use of cookies.

Continue Find out more about our use of cookies and similar technology

This content comes from a hidden element on this page.

The inline option preserves bound JavaScript events and changes, and it puts the content back where it came from when it is closed.

Remember Me