What is phenylketonuria?
It is a congenital and hereditary metabolic disease involving the abnormal metabolism of an amino acid, specifically phenylalanine. It results from a mutation in just one gene—PAH, located on chromosome 12. If untreated, the disease can lead to severe intellectual disability, seizures and behavioral disorders, that is, symptoms rooted in the central nervous system. Everything about PKU revolves around following a diet and monitoring phenylalanine levels. Phenylketonuria was not discovered until the 1930s. In Poland, an estimated 50 children with this disease are born each year. There are at least 500 forms of phenylketonuria, making it necessary to adapt the diet to the individual needs of each patient.
What are the symptoms of phenylketonuria, and why are the first three months of life so important in diagnosing the disease?
Phenylketonuria very often underlies moderate intellectual disability. It is also one of the more common metabolic disorders. In this disease, the patient's entire nervous system is affected. The most common symptoms include impaired motor function (reduced muscle tone), seizures, depression, aggression, autism, heart defects and microcephaly. Diagnosis is performed on the newborn's third day of life. It is based on a heel-prick blood test and a colonometric test, as well as a urine test for phenylketonuria. Diagnosis at such an early stage of life makes it possible to manage the child's care appropriately in order to limit any abnormalities and symptoms associated with phenylketonuria. The first three months of life are crucial. After this time, irreversible changes may occur in the central nervous system, which is why it is so important to establish a quick and accurate diagnosis and introduce a strict diet. It should be maintained at least until puberty. Women with phenylketonuria who are trying to have a child should also follow a strict PKU-adjusted diet during pregnancy to avoid harming the fetus.
Nutrition for people with phenylketonuria
Diet is the foundation of treatment for people with PKU. It is quite demanding, and several decades ago in Poland, patients had enormous problems accessing suitable food. They had to import it from abroad and pay a hefty price. Today, public awareness of the disease has improved significantly, as has access to specialized food products such as flour, pasta, cookies and bread for people with phenylketonuria. The diet of people with the disease requires iron discipline and must be managed in such a way that children can develop very well.