BACKGROUND: The optimal dose of protein substitute has not been determined in children with phenylketonuria (PKU). AIM: To determine if a lower dose of protein substitute could achieve the same or better degree of blood phenylalanine control when compared to the dosage recommended by the UK MRC.(1) METHODS: In a six week randomised, crossover study, two doses of protein substitute (Protocol A: 2 g/kg/day of protein equivalent; Protocol B: 1.2 g/kg/day protein equivalent) were compared in 25 children with well controlled PKU aged 2-10 years (median 6 years). Each dose of protein substitute was taken for 14 days, with a 14 day washout period in between. Twice daily blood samples (fasting pre-breakfast and evening, at standard times) for plasma phenylalanine were taken on day 8-14 of each protocol. The median usual dose of protein substitute was 2.2 g/kg/day (range 1.5-3.1 g/kg/day). RESULTS: When compared with control values, median plasma phenylalanine on the low dose of protein substitute increased at pre-breakfast by 301 mumol/l (95% CI 215 to 386) and in the evening by 337 micromol/l (95% CI 248 to 431). On the high dose of protein substitute, plasma phenylalanine concentrations remained unchanged when compared to control values. However, wide variability was seen between subjects. CONCLUSIONS: A higher dosage of protein substitute appeared to contribute to lower blood phenylalanine concentrations in PKU, but it did have a variable and individual impact and may have been influenced by the carbohydrate (+/- fat) content of the protein substitute.
RCT Entities:
BACKGROUND: The optimal dose of protein substitute has not been determined in children with phenylketonuria (PKU). AIM: To determine if a lower dose of protein substitute could achieve the same or better degree of blood phenylalanine control when compared to the dosage recommended by the UK MRC.(1) METHODS: In a six week randomised, crossover study, two doses of protein substitute (Protocol A: 2 g/kg/day of protein equivalent; Protocol B: 1.2 g/kg/day protein equivalent) were compared in 25 children with well controlled PKU aged 2-10 years (median 6 years). Each dose of protein substitute was taken for 14 days, with a 14 day washout period in between. Twice daily blood samples (fasting pre-breakfast and evening, at standard times) for plasma phenylalanine were taken on day 8-14 of each protocol. The median usual dose of protein substitute was 2.2 g/kg/day (range 1.5-3.1 g/kg/day). RESULTS: When compared with control values, median plasma phenylalanine on the low dose of protein substitute increased at pre-breakfast by 301 mumol/l (95% CI 215 to 386) and in the evening by 337 micromol/l (95% CI 248 to 431). On the high dose of protein substitute, plasma phenylalanine concentrations remained unchanged when compared to control values. However, wide variability was seen between subjects. CONCLUSIONS: A higher dosage of protein substitute appeared to contribute to lower blood phenylalanine concentrations in PKU, but it did have a variable and individual impact and may have been influenced by the carbohydrate (+/- fat) content of the protein substitute.
Authors: A M J van Wegberg; A MacDonald; K Ahring; A Bélanger-Quintana; N Blau; A M Bosch; A Burlina; J Campistol; F Feillet; M Giżewska; S C Huijbregts; S Kearney; V Leuzzi; F Maillot; A C Muntau; M van Rijn; F Trefz; J H Walter; F J van Spronsen Journal: Orphanet J Rare Dis Date: 2017-10-12 Impact factor: 4.123
Authors: Andrew A M Morris; Viktor Kožich; Saikat Santra; Generoso Andria; Tawfeg I M Ben-Omran; Anupam B Chakrapani; Ellen Crushell; Mick J Henderson; Michel Hochuli; Martina Huemer; Miriam C H Janssen; Francois Maillot; Philip D Mayne; Jenny McNulty; Tara M Morrison; Helene Ogier; Siobhan O'Sullivan; Markéta Pavlíková; Isabel Tavares de Almeida; Allyson Terry; Sufin Yap; Henk J Blom; Kimberly A Chapman Journal: J Inherit Metab Dis Date: 2016-10-24 Impact factor: 4.982
Authors: A MacDonald; A M J van Wegberg; K Ahring; S Beblo; A Bélanger-Quintana; A Burlina; J Campistol; T Coşkun; F Feillet; M Giżewska; S C Huijbregts; V Leuzzi; F Maillot; A C Muntau; J C Rocha; C Romani; F Trefz; F J van Spronsen Journal: Orphanet J Rare Dis Date: 2020-06-30 Impact factor: 4.123