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

• In PKU, the total protein prescribed varied widely between European centres.
• The amount of total protein appears to be influenced by geographical European region.
• North Europe prescribed highest amounts of total protein and least in West Europe.
• All PKU centres give in excess of the FAO/WHO/UNU safe levels of protein intake.

BackgroundThere appears little consensus concerning protein requirements in phenylketonuria (PKU).MethodsA 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.ResultsThe 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 < 1 year, > 2–3 g/kg/day; 1–3 years of age, > 2–3 g/kg/day; 4–10 years of age, > 1.5–2.5 g/kg/day) and Southern Europe (n = 10 centres) (infants < 1 year, 2.5 g/kg/day, 1–3 years of age, 2 g/kg/day; 4–10 years of age, 1.5–2 g/kg/day), than by Eastern Europe (n = 4 centres) (infants < 1 year, 2.5 g/kg/day, 1–3 years of age, > 2–2.5 g/kg/day; 4–10 years of age, > 1.5–2 g/kg/day) and with Western Europe (n = 25 centres) giving the least (infants < 1 year, > 2–2.5 g/kg/day, 1–3 years of age, 1.5–2 g/kg/day; 4–10 years of age, 1–1.5 g/kg/day). Total protein prescription was similar in patients aged > 10 years (1–1.5 g/kg/day) and maternal patients (1–1.5 g/kg/day).ConclusionsThe 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.