Main Article Content
phenyloketonuria, PKU, maternal, nutrition, diet,
The aim of this study was to determine the relationship between the low-phenylalanine diet and perinatal parameters in children of women with phenylketonuria. An attempt was also made to determine whether starting the diet only after the beginning of pregnancy increases the risk of maternal phenylketonuria syndrome in children. Forty-five women from Poland, who were diagnosed with phenylketonuria PKU were recruited. Each subject completed a two-part medical questionnaire. The questions in the first part concerned pregnancy. Part two of the questionnaire referred to the neonates and asked for perinatal parameters. 13% of the surveyed women did not use a low-phenylalanine diet in the period prior to conception, and thus reported that they did not achieve metabolic control of phenylketonuria. The remaining 87% of respondents following this diet during the period prior to conception. Women using the low-phenylalanine diet in the period prior to conception gave birth to children with significantly higher birth weights and larger head circumferences. In all the women, regardless of whether they used the low phenylalanine diet prior to pregnancy or not, the average blood phenylalanine concentration decreased over subsequent trimesters. Birth defects were significantly more common in the case of women who did employ the low-phenylalanine diet in the period prior to conception. We underline that the treatment of pregnant women with phenylketonuria is of great importance to prevent neonatal sequelae. We strongly recommend starting treatment prior to conception, as the deleterious effect of not using the low-phenylalanine diet in period prior to conception is very clear.
2. Yıldız, Y, Sivri HS. Maternal phenylketonuria in Turkey: outcomes of 71 pregnancies and issues in management. European Journal of Pediatric. 2019; 178(7): 1005-1011.
3. Żółtkowska J, Hozyasz KK, Nowacka M. Prevention of maternal phenylketonuria. Dietary management in the preconception period and during pregnancy. Pediatria i Medycyna Rodzinna. 2018; 14 (1): 47-53.
4. Lichter-Konecki U, Vockley J. Phenylketonuria: Current Treatments and Future Developments. Drugs. 2019; 79(5): 495-500.
5. Lenke RR, Levy HL. Maternal phenylketonuria and hyperphenylalaninemia. An international survey of the outcome of untreated and treated pregnancies. The New England Journal of Medicine. 1980; 20: 303(21): 1202-1208.
6. Vockley J, Andersson HC, Antshel KM, et al. Phenylalanine hydroxylase deficiency: diagnosis and management guideline. Genetics in Medicine. 2014; 16: 188–200.
7. Smith I, Beasley MG, Ades AE. Intelligence and quality of dietary treatment in phenylketonuria. Archives of Disease in Childchood. 1990; 65(5), 472–478.
8. Blau N, van Spronsen FJ, Levy HL. (2010). Phenylketonuria. Lancet. 2010; 376(9750): 1417–1427.
9. Dawson C, Murphy E, Maritz C, et al. Dietary treatment of phenylketonuria: the effect of phenylalanine on reaction time. Journal of Inherited Metabolic Disease. 2011; 34(2): 449–454.
10. Channon S, Goodman G, Zlotowitz S, et al. Effects of dietary management of phenylketonuria on long-term cognitive outcome. Archives of Disease in Childchood. 2007; 92(3): 213–218.
11. Weglage J, Fromm J, van Teeffelen-Heithoff A, et al. Neurocognitive functioning in adults with phenylketonuria: results of a long term study. Molecular Genetics and Metabolism. 2013; 110: 44-48.
12. Koch R, Burton B, Hoganson G, et al. Phenylketonuria in adulthood: a collaborative study. Journal of Inherited Metabolic Disease. 2002; 25(5): 333–346.
13. Singh RH, Rohr F, Frazier D, et al. Recommendations for the nutrition management of phenylalanine hydroxylase deficiency. Genetics in Medicine. 2014; 16(2): 121-131.
14. Prick BW, Hop WC, Duvekot JJ. Maternal phenylketonuria and hyperphenylalaninemia in pregnancy: pregnancy complications and neonatal sequelae in untreated and treated pregnancies. American Journal of Clinical Nutrition. 2012; 95(2): 374–382.
15. Sharman R, Sullivan KA, Young RM, et al. Tyrosine monitoring in children with early and continuously treated phenylketonuria: results of an international practice survey. Journal of Inherited Metabolic Disease. 2010; 33: 417–420.