Pol. Merkur. Lek (Pol. Med. J.), 2016, XL/238: 223-229 Maximize

Pol. Merkur. Lek (Pol. Med. J.), 2016, XL/238: 223-229

Title: High plasma folate in patients with phenylketonuria 

Authors:  Zielińska M, Żółkowska J, Przybylska-Kruszewska A, Gładysz D, Korycińska-Chaaban A, Nowacka M, Hozyasz KK. 

More details


40,00 zł


High plasma folate in patients with phenylketonuria

Zielińska M1, Żółkowska J2, Przybylska-Kruszewska A1, Gładysz D1, Korycińska-Chaaban A2, Nowacka M1,2, Hozyasz KK1.

Institute of Mother and Child in Warsaw, Poland: 1Department of Pediatry; 2POut-patient Department of Metabolic Diseases

Phenylketonuria is an inborn error of metabolism treated with a closely monitored low phenylalanine diet. Protein substitutes used for treatment are supplemented with vitamins and micronutrients.
The aim of this study
was to investigate plasma folic acid concentrations in children with phenylketonuria.
Material and methods
. Retrospective analysis of medical records of 73 patients with phenylketonuria and 28 with mild hyperphenylalaninemia (on normal diet) was carried out. Intake of folic acid was calculated on the basis of protein substitute intake. Folate concentrations were analyzed according to their intake, and concentration of homocysteine and phenylalanine.
. In 76.7% patients with phenylketonuria intake of folic acid exceeded recommended dietary allowance. Serum folic acid concentrations above upper reference level were detected in 75.3% patients with phenylketonuria and only in 25% patients with hyperphenylalaninemia (p<0.0001). Strong positive correlation between daily intake of folic acid (with protein substitute) and concentration plasma folic acid (corr=0.55, p<0.0001) has been observed.
. Low phenylalanine diet using protein substitutes currently available in Poland predisposes to high concentration of plasma folic acid. The security of folic acid hipersupplementation in patients with phenylketonuria requires further detailed research.

Key words: phenylketonuria, hyperphenylalaninemia, folic acid, diet

Pol Med J, 2016; XL (238); 223–229