Phenylketonuria - Medtick
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Phenylketonuria

What is it?

A rare genetic disorder where one cannot breakdown the amino acid phenylalanine (amino acids are from the proteins from the food we eat for example meat and fish) because one does not have the chemicals (enzyme) to break it down.

  • Phenylalanine needs to be converted to another amino acid called tyrosine which plays a role in our skin where it created melanin which is needed for us to absorb uva rays so we don’t burn easily and get skin cancer as well as other functions.
  • Tyrosine also helps us to create various neurotransmitters such as dopamine, noradrenaline and thyroxine needed for well being, mood and muscle control and our ‘flight and fight response’  as well as participates in the synthesis of enkephalins providing pain-relieving effects in the body.
  • Any phenylalanine in the food someone eats cannot be digested properly and builds up and collects in the body causing problems in the brain and other organs.

Cause

  • Family history (both father and mother must have PKU)
  • Genetic disorder which affects the enzyme lacking
  • Lack of enzyme: Phenylalanine Hydroxylase

Vitamins, herbals and minerals

Symptoms

  • Pale skin/blonde hair/blue eyes (phenylalanine is used to make melanin which gives one a dark colour skin and hair)?
  • Dry and scaly skin?
  • ‘Musty’ odour resulting from the build up of phenylalanine in hair, skin and urine?
  • Irritability and/or temper tantrums?
  • Slow reaction times [Phenylalanine is converted to  epinephrine (adrenaline)], norepinephrine (noradrenaline), and dopamine needed for fight and flight response)?
  • Aching, painful muscles, muscle cramps/spasms/stiffness?
  • Tremors?
  • Abdominal pain and/or are constant violently vomiting or vomiting longer than two days (one day if a child)?
  • A small head?
  • Short stature?
  • Difficult to concentrate and/or difficulty in concentrating and/or memory problems?
  • Learning disabilities?
  • Hyperactivity?

Complications /Information to beware of/General tips:

Do not wait, phone for an ambulance if have or develop:

This condition can lead to:

Pregnancy

  • A woman who has PKU herself and is pregnant must strictly control her phenylalanine levels before and during pregnancy to avoid causing damage to her unborn child.
  • High levels of phenylalanine in a pregnant woman can cause her child to have slow growth, developmental delays, small head size and other disorders.
  • With careful monitoring and control, women with PKU can give birth to healthy children.
  • A woman with PKU can pass the PKU gene to her child, but the child will not develop PKU unless another copy of the gene is inherited from the father.

Harvard Health Publications

Diet

Phenylalanine is found in most protein-containing foods, so people with PKU are advised to follow a special low-protein diet.

They should avoid high-protein foods such as:

  • Meat
  • Poultry (chicken and turkey)
  • Fish
  • Eggs
  • Milk and cheese
  • The artificial sweetener aspartame:
    • Sugar substitutes – such as artificial sweeteners often used in tea and coffee
    • Fizzy drinks (especially diet versions)
    • Chewing gum
    • Squashes and cordials
    • Some alcopops

Each person’s protein needs vary over a lifetime. Children with PKU need to be sure they get enough protein to grow and develop properly. However, they must always avoid having too much phenylalanine in their body at any time. The levels of phenylalanine in the blood need to be monitored throughout the person’s lifetime.

Harvard Health Publications

This condition may show similar symptoms to:

Please talk to your healthcare professional (i.e. Medical Doctor/Pharmacist) for further advice

Detailed Information

Please copy and paste any key words from the title: Phenylketonuria in the following respective 'Medtick References and/or Sources' to find out more about the disease (this also may include diagnosis tests and generic medical treatments).

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