Growth and Nutritional Status of Phenylketonuric Children and Adolescents

BACKGROUND: The goal of this study was to assess the anthropometric and biochemical parameters of children and adolescents with phenylketonuria (PKU). METHODS: The participants in this cross-sectional study ranged in age from four to 18 years old. Biochemical markers such as vitamin B12, folic acid, iron, ferritin, calcium, 25-hydroxy vitamin D3, zinc, plasma phenylalanine (Phe) and tyrosine (Tyr) levels in blood were evaluated, as well as demographics and anthropometric measurements. A three-day dietary recall questionnaire was completed by all individuals. RESULTS: 80% (64) of the 80 patients (42 females, 52.5%) had typical PKU. Consanguineous marriages were found in 57.5% (46) of the patients’ parents. According to the height for age index, 17.5% of the study group (n = 14) were short or very short. According to age-related weight and body mass index (BMI), 37.5% (n = 30) and 43.8% (n = 35) of people are obese or overweight, respectively. Biochemical tests revealed increased vitamin B12 levels and 25-hydroxy vitamin D3 deficiency in 35% (n = 28) of the patients, insufficient folic acid in 12.5% (n = 10), and elevated phenylalanine levels in 70.3% (n = 45) of children under 12 years old, and adolescents 62.5% (n = 10). A high Phe intake (OR = 4.44, CI %95 = 1.27–15.57) is a risk factor for obesity and overweight. CONCLUSION: Patients with PKU had a high rate of overweight and obesity. PKU patients who are overweight or obese do not differ from normal-weight patients in terms of dietary intake or laboratory findings (except for serum iron levels). One-third of patients with phenylketonuria were vitamin D deficient and had a BMI/A index of overweight/obese. It is recommended to use special medical food to help solve energy and nutrient deficiencies.