ABC Medical Center > Phenylketonuria

What is Phenylketonuria?

21:54 - 4 May , 2021


It is a hereditary condition in which there is an excessive accumulation of phenylalanine in the body, as a result of an abnormal gene responsible for producing an enzyme that helps metabolize this amino acid present in foods with a high percentage of protein.

By not having the enzyme, phenylalanine accumulates when consuming foods such as meat, eggs, milk, fish, or artificial sweeteners such as aspartame, causing serious health disorders in people of any age, such as:

  • Phenylketonuric mothers can suffer spontaneous abortions and their babies can be born with birth defects.
  • Permanent neurological damage.
  • Intellectual disabilities.
  • Seizures and tremors.
  • Behavioral, emotional, and social problems.

Signs and symptoms Phenylketonuria

Babies do not usually have symptoms at birth but until a few months later. Its severity will depend on the type of phenylketonuria:

  • Classic: the enzymes do not fulfill their function, so phenylalanine concentration levels are extreme, causing serious neurological damage.
  • Mild: here the enzyme is decreased, but it continues to perform its function partially, which minimizes the risk of possible complications.

The most frequent symptoms are:

  • Slow development.
  • Behavioral, emotional, and social changes.
  • Psychiatric abnormalities.
  • Musty smell in the mouth, skin, and urine.
  • Seizures.
  • Eczema.
  • Clear eyes and skin by preventing the transformation of phenylalanine into melanin.
  • Microencephaly.
  • Hyperactivity.
  • Intellectual disabilities.

If pregnant phenylketonuric women do not follow an adequate diet, they may have a spontaneous abortion or if they continue with the pregnancy, their children may experience:

  • Low birth weight.
  • Slow development.
  • Changes in the face.
  • Microencephaly.
  • Heart conditions.
  • Intellectual disability.

Diagnosis and treatment Phenylketonuria

To find out if you or your child suffer from phenylketonuria, blood and urine tests are required, as well as genetic tests to identify the genetic mutation that causes it. The treatment plan consists of:

  • Low protein diet.
  • Take a special food supplement for phenylketonurics.
  • Neutral amino acid therapy.
  • Specific medications.

In our Pediatric Center, a team of highly trained specialists awaits you 24 hours a day, 365 days a year, ensuring optimal care and results by providing care based on clinical practice guidelines and international protocols.


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