Impact of a Phe-Restricted Diet on Gut Health in Children with PKU

  • Research type

    Research Study

  • Full title

    Impact of a phenylalanine-restricted diet on the microbiota composition and metabolome of children with PKU

  • IRAS ID

    353831

  • Contact name

    Anita MacDonald

  • Contact email

    anita.macdonald@nhs.net

  • Sponsor organisation

    Birmingham Women's and Children's NHS Foundation Trust

  • ISRCTN Number

    ISRCTN00000000

  • Clinicaltrials.gov Identifier

    NCT00000000

  • Clinicaltrials.gov Identifier

    N/A, N/A

  • Duration of Study in the UK

    1 years, 2 months, 31 days

  • Research summary

    Phenylketonuria (PKU) is an inborn error of phenylalanine (Phe) metabolism. The cornerstone of treatment is a Phe-restricted diet, which aims to prevent neurological sequelae and promote normal growth and development. A subset of milder patients with PKU respond to the synthetic form of tetrahydrobiopterin (BH4), which enables them to follow a less restrictive diet. The role of the gut microbiota in health and disease has been increasingly recognised, with diet being a key factor influencing its composition. Therefore, the aim of this study is to explore the gut microbiota and metabolomics of children with PKU and compare those on BH4 treatment with those exclusively on a Phe-restricted diet and healthy children. This observational study will recruit children with PKU (aged 3-17) attending Birmingham Children's Hospital, who are either on an exclusive Phe-restricted diet (n=30) or taking BH4 (n=30), as well as healthy controls (n=30). Faecal samples will be collected for microbiota analysis through sequencing, alongside metabolite profiling. With this project, we aim to provide novel insights into the gut microbiota composition and metabolomics of children with PKU with different dietary restrictions. These findings could contribute to the development of improved nutritional strategies and protein substitutes specifically designed to support gut health more effectively. Additionally, the study may shed light on the potential benefits of a less restrictive diet (with BH4 supplementation) in restoring a healthier gut microbiota. Ultimately, the results could assist clinicians in making more informed therapeutic decisions and significantly enhance the health and quality of life of patients with PKU. By improving gastrointestinal well-being, this research has the potential to make a meaningful contribution to the overall management of PKU.

  • REC name

    Wales REC 7

  • REC reference

    25/WA/0150

  • Date of REC Opinion

    4 Jun 2025

  • REC opinion

    Further Information Favourable Opinion