| Abstract [eng] |
Phenylketonuria is a rare autosomal recessive metabolic disorder. Mutations in the PAH gene result in a lack of phenylalanine hydroxylase in the body, which disrupts the translation of phenylalanine into tyrosine, resulting in an excess of it in the blood which is toxic to the brain. The prevalence of the disease in the world is 1 in 24,000 people. In developed countries, early diagnosis of phenylketonuria is possible due to the newborn screening program. Early treatment prevents disease progression and the development of mental, behavioural, neurological, and physical disorders. Regardless of treatment initiation time, all found cases had white matter disturbances. The most common changes seen in magnetic resonance imaging are intramyelinating oedema affecting the periventricular region. Diffusion kurtosis imaging was found to be the more appropriate examination method for detecting subclinical changes in cerebral white matter. In addition, inadequate adherence to treatment or late initiation of treatment results in varying degrees of mental disability. It has been noticed that in some cases individuals with phenylketonuria and high blood phenylalanine concentration preserve a normal IQ, but the prevailing mechanism of pathogenesis remains unclear, and only hypotheses are presented to explain them. It is important to perform imaging tests on all patients with phenylketonuria and continuously assess them later in life to gather more data on white matter changes and the effect of early versus late treatment. |
