A blood test can help detect phenylketonuria.
Phenylketonuria is a metabolic disorder that causes the body to be unable to metabolize the amino acid called phenylalanine in the liver . Also known as PKU , it is an inherited disease caused by the lack of an enzyme called phenyl alanine hydroxylase (abbreviated as FAOH) or tyrosine hydroxylase (DHPR) .
The origin of this term comes from the English phenylketonuria , hence the initials that refer to this disorder (PKU). This genetically transmitted disease is characterized by affecting certain chemical components of the body, the consequence of which can be intellectual disability .
People who are born lacking the enzyme phenyl alanine hydroxylase (enzymes allow the body to activate certain chemical reactions), which resides in the liver, cannot synthesize phenylalanine from food and it begins to accumulate excessively in the body. It should be noted that people who do not suffer from this disease can synthesize this substance and convert it into L-DOPA , a neurotransmitter essential for the normal functioning of neurological development. There are seven essential amino acids for people (leucine, tryptophan, valine, isoleucine, tyrosine, methionine and phenylalanine), which are obtained from the synthesis of certain components present in different foods.
Studies on phenylketonuria
Although it is a disease about which there is not much awareness, it is known that in the United States alone, around 25,000 babies are born with PKU each year ; Furthermore, although its specific origin is unknown, it is believed that it is more common in individuals whose ancestors have been Northern Europeans or indigenous natives of North America .
This genetic alteration that is transmitted from father to son had one of its main disseminators in Ivar Asbjørn Følling . This Norwegian medical expert was the one who was in charge of describing the disease in 1934 , before any other specialist.
Følling warned that the enzymes mentioned above are responsible for hydroxylating phenylalanine, in a reaction that allows the production of tyrosine. This means that, if the body does not have any of these enzymes, it will suffer from an excess of phenylalanine in the blood (since this substance will not be able to convert into tyrosine), and will result in other disorders .
Those who suffer from phenylketonuria should not consume milk.
Symptoms and effects
The symptoms presented by those children who suffer from this disease are hair, eye and skin color that is lighter than the rest of their siblings (phenylalanine is one of the main responsible for the production of melanin , which allows coloration in the skin and hair); delay in intellectual abilities ; a smaller head size than expected; sudden movements and hyperactivity ; attacks of convulsions and tremors ; and an unusual hand position. It should be added that those people who do not receive treatment or avoid foods containing phenylalanine begin to eliminate a strange odor (comparable to that given off by mice or mold) through their skin, urine and breath ; This odor is due to the accumulation of this substance in the body.
The accumulation of phenylalanine and other substances (such as phenylpyruvate ) causes damage to the brain and central nervous system. Those who suffer from phenylketonuria, therefore, can experience everything from mental disability to seizures and spasms, to tremors and skin rashes.
Diagnosis and treatment of phenylketonuria
Thanks to the tests and diagnoses that allow this disease to be detected in newborn children, it is possible to treat this condition , helping these individuals to grow and develop in a healthy way. The treatment of phenylketonuria usually includes a diet that excludes foods with high amounts of phenylalanine, such as eggs or milk, as well as those containing aspartame .
To detect phenylketonuria, simple blood tests are performed (in some countries this test is among the mandatory tests performed on neonates). If it is positive, new tests are performed to confirm the diagnosis and proceed to treatment. .
It is important to know that this disease is perfectly treatable and that a series of preventions will be enough to ensure healthy growth for those children who suffer from phenylketonuria. The treatment includes a diet low in phenylalanine that requires exhaustive supervision by professionals, which if carried out correctly will ensure a much healthier adult life in physical and mental aspects than if it is carried out in a less committed way.
There are alternatives specially developed for people who suffer from this disease that allow them to lead a healthy life without having to do without foods that are essential for growth, such as the aforementioned milk . Lofenalac infant milk powder, for example, is used as a source of protein for individuals with phenylketonuria, which is made with a low content of phenylalanine and balanced in terms of the amount of the rest of the essential components for growth, such as amino acids.
Furthermore, it is vitally important that those parents who have children with this disease have a clear awareness of the consequences that could affect them if said disease is not treated, or if the diet recommended by specialists is not properly followed, among which is a chronic mental retardation that will appear in the first year of life and that will already be irrevocable. Likewise, if parents do not know if they can carry the gene for this disease in their genes, it is essential that when thinking about conceiving a new life they perform the respective enzyme analyzes in order to be prepared in case their children could be carriers of said disease.
Finally, those women who suffer from phenylketonuria must follow a strict diet , not only before becoming pregnant, but also during pregnancy and breastfeeding, even if the baby was born without the defective gene, because the accumulation of this substance in the mother's body could cause consequences in the child's body.