What are the symptoms of phenylketonuria in infants aged 0 to 3 months?
Mar 18, 2024
Source: Cainiu Health
Dr. Zhou Xiaofeng
Introduction
Phenylketonuria may present symptoms such as low muscle tone, dry skin, frequent eczema, abnormal skin and hair, and delayed intellectual development. It should be noted that symptoms can vary among infants, and not all of the above symptoms will necessarily appear. Once diagnosed through newborn screening, treatment should begin immediately as directed by a physician. The earlier the treatment starts, the better the outcome tends to be.
Phenylketonuria (PKU) is a common inherited amino acid metabolism disorder. In infants aged 0 to 3 months, phenylketonuria may present symptoms such as hypotonia, dry skin, tendency to develop eczema, abnormal skin and hair pigmentation, and delayed intellectual development. If any abnormalities are observed, prompt medical consultation is recommended. Detailed analysis is as follows:
1. Hypotonia: Due to enzyme deficiencies in the phenylalanine metabolic pathway, phenylalanine and its keto acids accumulate in the body and are excreted in large amounts in urine. This condition typically follows an autosomal recessive inheritance pattern. Infants may exhibit symptoms of low muscle tone or floppiness.
2. Dry skin: Abnormal fat metabolism may also lead to dry skin in affected infants.
3. Tendency to develop eczema: Infants with phenylketonuria may be prone to eczema due to impaired skin barrier function.
4. Skin and hair abnormalities: The disease causes insufficient melanin synthesis, which may result in paler skin compared to normal infants, and hair and skin may appear yellowish.
5. Delayed intellectual development: Over time, infants with phenylketonuria may experience delayed cognitive development; however, this symptom may not become apparent until after three months of age.
It should be noted that symptoms can vary among individual infants, and not all of the above symptoms will necessarily occur. Once diagnosed through newborn screening, treatment should begin immediately as directed by a physician. The earlier treatment is initiated, the better the therapeutic outcome.
