Practices in prescribing protein substitutes for PKU in Europe: No uniformity of approach

Abstract Background There appears little consensus concerning protein requirements in phenylketonuria (PKU). Methods A questionnaire completed by 63 European and Turkish IMD centres from 18 countries collected data on prescribed total protein intake (natural/intact protein and phenylalanine-free protein substitute [PS]) by age, administration frequency and method, monitoring, and type of protein substitute. Data were analysed by European region using descriptive statistics. Results The amount of total protein (from PS and natural/intact protein) varied according to the European region. Higher median amounts of total protein were prescribed in infants and children in Northern Europe (n=24 centres) (infants 2–3g/kg/day; 1–3years of age, >2–3g/kg/day; 4–10years of age, >1.5–2.5g/kg/day) and Southern Europe (n=10 centres) (infants 2–2.5g/kg/day; 4–10years of age, >1.5–2g/kg/day) and with Western Europe (n=25 centres) giving the least (infants 2–2.5g/kg/day, 1–3years of age, 1.5–2g/kg/day; 4–10years of age, 1–1.5g/kg/day). Total protein prescription was similar in patients aged >10years (1–1.5g/kg/day) and maternal patients (1–1.5g/kg/day). Conclusions The amounts of total protein prescribed varied between European countries and appeared to be influenced by geographical region. In PKU, all gave higher than the recommended 2007 WHO/FAO/UNU safe levels of protein intake for the general population.