Introduction to the characteristics of phenylketonuria

What is the brief introduction to the characteristics of phenylketonuria? Many people don't know much about phenylketonuria, but once this disease appears in a child, it must be checked and treated in time, otherwise it will have a great impact on life. So, let's take a look at the brief introduction to the characteristics of phenylketonuria!

Most PKU children are normal at birth, with no obvious special clinical symptoms in the neonatal period. Untreated children gradually show delayed intellectual and motor development after 3 to 4 months, with hair turning from black to yellow, skin white, a special mouse odor on the body and urine, and often eczema. As they age, the mental retardation of children becomes more and more obvious. About 60% of older children have severe intellectual disabilities. Two-thirds of children have mild neurological signs, such as increased muscle tension, hyperreflexia, microcephaly, etc. Severe cases may have cerebral palsy.

To prevent the onset of phenylketonuria, early diagnosis and early treatment are necessary to avoid damage to the nervous system caused by excessive phenylalanine metabolites, such as phenylpyruvate, phenylacetate and phenyllactic acid. Since it takes a certain amount of time for phenylpyruvate, phenylacetate and phenyllactic acid in the body to accumulate to the concentration required to damage the brain, even in PKU children, the concentration of these abnormal metabolites often only increases within 1 to 2 months after birth, which does not cause irreversible damage.

If timely diagnosis and effective treatment are given at this stage, damage to the nervous system can be avoided. This method of detecting diseases within one month after the birth of an infant, before the onset of the disease, is called neonatal disease screening. It is an effective method for early diagnosis. Blood is collected from the newborn three days after birth to test the blood phenylalanine concentration. If the phenylalanine level is elevated, further diagnosis and examination are required. After the diagnosis is confirmed, effective treatment is carried out to reduce the blood phenylalanine and its abnormal metabolites to normal, thus achieving the purpose of preventing the disease.

To prevent the birth of children with PKU, the baby should be diagnosed before birth. If the baby is diagnosed with PKU, the parents can decide whether to keep the baby. This method of diagnosis before birth is called prenatal diagnosis. Prenatal diagnosis of PKU is suitable for parents who already have PKU and want to have another baby.