Abstract

Objective: The aim of this study was to determine the dietary habits of patients with phenylketonuria (PKU) in different age groups, to assess energy, protein and phenylalanine intakes, and to evaluate dietary compliance and its effect on metabolic control.

Material and Methods: The study, conducted between 1 March 2022 and 30 September 2022, the study involved 20 children aged 2-18 diagnosed with PKU at the Department of Pediatric Metabolism Outpatient Clinic of Ankara Bilkent City Hospital. Participants were evaluated for diet compliance and had their blood phenylalanine and tyrosine levels were measured.

Results: Among the 20 patients, 42.9% (n=9) were female and 57.1% (n=11) were male, with a mean age of 4.7±3.22 years. Age distribution was 70% (n=14) aged 2-6, 20% (n=4) aged 6-10, and 10% (n=2) aged 10-13. Patients attended four follow-ups over six months. A moderate negative correlation was found between daily dietary phenylalanine and blood phenylalanine levels in the first and last controls, and a high negative correlation in the 2nd and 3rd controls (p=0.006, p<0.001, p<0.001, p=0.013). A positive moderate correlation was found between the frequency of daily amino acid mixture consumption and diet compliance (p=0.025). Increased meal frequency improved diet compliance. No significant relationship was found between blood phenylalanine levels and amino acid mixture consumption, diet compliance, or daily amino acid mixture consumption frequency.

Conclusion: In PKU, nutritional habits, daily phenylalanine intake and amino acid mixture consumption frequency impact dietary compliance and metabolic control. Lifelong medical nutrition therapy requires multidisciplinary team support, frequent follow-ups and adherence to the recommended diet.

Keywords: Metabolic control, phenyalanine, phenylketonuria

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How to cite

1.
Özen Yeşil B, Koç N, Köseler Beyaz E, Kucukcongar A, Bilginer Gürbüz B, Kasapkara ÇS. Evaluation of the Effect of Diet Adherence on Nutritional Status and Metabolic Control in Children with Phenylketonuria Consuming a Phenylalanine-Restricted Diet: A Single-Center Study. Turk J Pediatr Dis [Internet]. 2025 Mar. 24 [cited 2025 May 25];19(2):64-70. Available from: https://turkjpediatrdis.org/article/view/1095