Global Clinical Practice in Transitioning Protein Substitutes for Children with Phenylketonuria
Ozlem Yilmaz Nas1,2, Catherine Ashmore1, Sharon Evans1
1Birmingham Women's and Children's Hospital, Birmingham B4 6NH, UK.
Abstract:
Background: Protein substitutes are essential in the dietary management of phenylketonuria (PKU). Transition from first-stage phenylalanine (Phe)-free infant formula to second- and third-stage protein substitutes is carefully managed to meet a child's evolving nutritional needs, feeding abilities, and developmental progression. However, clinical protocols, product access, and reimbursement vary globally. This study assessed international transition practices. Methods: A cross-sectional online survey explored health professionals' practices on transition timing, influencing factors, product forms, casein-glycomacropeptide (cGMP) use, and perceived barriers and facilitators. Results: A total of 106 professionals from 32 countries participated: Europe (67%), Asia (12%), North America (10%), South America (8%), and Oceania (3%). Dietitians led transitions in 83% of centers. First-stage Phe-free infant formula was typically discontinued at 1-2 years (66%). Second-stage substitutes were introduced at 6-12 months in Europe (61%) and Oceania (100%), but after age one in Asia (69%), North America (72%), and South America (100%). Influencing factors included weaning alignment (46%) and nutritional needs (42%). Semi-solids were preferred in Europe (56%) and Oceania (67%), while powdered drinks dominated in Asia (62%), North America (82%), and South America (100%). Third-stage protein substitutes were introduced at 3-5 years (45%), with later transitions more common in South America (88%) and North America (63%). Ready-to-drink forms were frequent in Oceania (100%), Asia (92%), and Europe (85%). cGMP was prescribed by 61%, mainly guided by preference, Phe tolerance, and adherence; 26% reported no access. Key facilitators for transition included motivation (79%) and sensory properties (69%); barriers included aversion (70%) and poor taste/texture (69%). School involvement was reported by 32%. Conclusions: Protein substitute transition practices in PKU vary globally. International guidance and equitable product access are needed.
Related Concept Videos
Inborn Errors of Metabolism
Overview of Protein Metabolism
Amino acids play various roles in the body once they are absorbed into cells. They are restructured...
Chronic Kidney Disease III: Interprofessional Care
Physiological Pharmacokinetic Models: Assumption with Protein Binding
Protein Absorption
Protein Kinases and Phosphatases
Protein kinases
Many proteins in the cell are regulated by phosphorylation, the addition of a phosphate group. A family of enzymes called kinases...


