[Evaluation of physical development in children with classical phenylketonuria]

Classical phenylketonuria (PKU) is hereditary disease, which is based on the disturbance of phenylalanine conversion to tyrosine. The basic treatment of PKU is low phenylalanine diet. Prolonged restriction of natural protein may have a negative impact to PKU patient growth and physical development. The objective was to evaluate the physical development of patients with classical PKU at birth and on the diet based on the products with different chemical composition without phenylalanine. 257 PKU patients have been examined with the computer program "WHO Anthroplus 2009". All patient were born at term. Z-score of body weight, height and body mass index (BMI) to age has been retrospectively estimated. Patients were divided into 2 groups: group 1--101 children born in 1980-1993 were fed by unadapted specialty products based on protein hydrolyzate with restricted phenylalanine, and group 2--156 children born in 1995-2012 were fed by contemporary amino acid mixtures without phenylalanine. All newborn PKU patients had the middle for age Z-score of weight and BMI, 21% of neonates had high Z-score growth. Before the diet therapy BMI Z-score was normal in 84.1% patients in group 1 and 87.2% patients of group 2. After 6 mo of treatment with low phenylalanine diet the number of patient with normal BMI Z-score was 71.3% in group 1 against 95.6% in group 2. Thus, using of modern amino acid mixtures without phenylalanine, enriched with essential nutrients can promote the normal physical development of PKU patients.