1. Growth retardation and mental retardation
In addition to growth retardation, the main manifestation is mental retardation. pku treatment After 4-9 months of life, the IQ is lower than that of normal infants of the same age. The IQ of heavy workers is below 50, and language development disorder is especially obvious.
2. Neuropsychiatric manifestations
The brain atrophy and cerebellar malformation may occur, with recurrent spasms that tend to subside with age. Tonsillar hyperactivity and hyperreflexia. Frequent excitement, restlessness, hyperactivity and abnormal behavior.
3. Skin and hair performance
The skin is often dry and prone to eczema and skin scars. Due to the inhibition of tyrosinase, the synthesis of melanocytes can be reduced, so the affected children appear hair color light and brown.
Due to the lack of phenylalanine hydroxylase, phenylalanine from another important pathway from the production of phenyl lactic acid has been increasing, from sweat and urine discharge of different and musty smell (or rat odor).
PKU children's examination and determination
PKU is mainly detected and treated as soon as possible through clinical screening of peripheral blood from the heel of newborns.
1. Blood phenylalanine assay
If the blood phenylalanine level exceeds 120 mmol/L, the test will be positive. If the blood tyrosine level can also be measured, the ratio of phenylalanine to tyrosine can be analyzed and the test will be positive if it exceeds 2.
Tandem mass spectrometry can quickly detect the concentration of phenylalanine and tyrosine and automatically calculate the ratio, thus reducing the false-positive or false-negative rate.
2. Central nervous system
The analysis of urine pteridine spectra, determination of red blood cell dihydrobiopterin reductase activity, and cranial MRI can further provide a definitive corporate diagnosis and understanding of the severity of impairment of the central nervous system.
