The Condition Phenylketonuria (PKU)

This is a diagram showing what the genes of an unaffected father and mother carrier are, and the possibilities of their child  having PKU.

    Phenylketonuria was introduced in 1934 by a Norwegian doctor named Asbjorn Folling. He found a substance in the urine of both a mother's handicapped children, and identified the substance as phenylketone, which gave him the name phenylketonuria. This rare condition builds up of a natural substance called phenylalanine that's in your body. It is a building block of proteins. Newborns are tested for PKU when they are born. Phenylalanine is found in the protein part of the different foods we eat, and it is a treatable condition. The development and the normal growth of the baby's brain was affected. Sometimes, children may become severely mentally abnormal. The purpose of the treatment is to stop the build up of phenylalanine, by using a special kind of diet. The treatment for PKU has been available since the 1950's. Doctors and many health professional are still learning about this condition. The normal diet is made up of sugars, proteins, and fats. The protein food can't be used properly in children who have PKU.

Phenylalanine is one of the amino acids, which explains why it can't be used properly. Whenever you eat meat, it begins by digesting in the stomach. It breaks down the links joining the amino acids together. Phenylalanine is used for growth. The extra amino acids are changed into other substances called enzymes which are special chemicals. Usually the excess phenylalanine is changed into another amino acid called tyrosine, by an enzyme called phenylalanine hydroxylase. Tyrosine makes a lot of important substances such as chemical messengers and hormones for the brain.

 In children who have phenylketonuria the enzyme phenylalanine hydroxylase is not present or it is working very poorly. The body is not capable of changing phenylalanine into tyrosine. This is what causes results in high concentrations of phenylalanine in the blood. So, in order to treat PKU you must lower the amount of phenylalanine in your diet so your body has just enough for tissue repair and growth. There have been products developed that have little or none phenylalanine. If your baby has PKU then you will have to send samples of your baby's blood to the hospital laboratory to check that the phenylalanine level is being kept at a normal limit. So, you have to eat food that has low protein, such as fruit juice and fruits. Around the age of 10-14 years old the diet can be discontinued safely.

Adults who have this condition usually have nervous system disorders such as poor coordination of the hand. Parents who have a baby with PKU had a normal gene and one faulty gene for the enzyme phenylalanine hydroxylase. 1 person in 50 people have one abnormal gene for PKU, and is a carrier of it. Parents who have more than one kid, it doesn't mean that all of their children will have this condition because each child inherits one gene from each parent. They can either inherit a PKU gene or a normal gene from each parent. The chances of your child with phenylketonuria having a partner who is a carrier of the PKU gene is about 1 in every 50 people. The risk of them having a child with PKU is around 1 in 100. Babies born to a mother with PKU with high phenylalanine levels may have a chance of being physically and mentally damaged in the womb, and the effects are permanent. A good developed diet control must be started before having a planned pregnancy. If an unplanned pregnancy occurs, then you must seek for advice. I have a good understanding about this condition PKU and how it is identified in babies, and how you treat it.