Protein substitute needs for patients with Phenylketonuria on BH4 treatment

For around fifty of the known inherited metabolic disorders, the management of these conditions is done through a lifelong commitment to a restricted diet1. In the example of the amino acid disorder Phenylketonuria (PKU), individuals cannot break down the amino acid phenylalanine. If left untreated, this may lead to irreversible brain damage2-4.

For certain patients with PKU, pharmaceutical treatment with synthetic tetrahydrobiopterin (BH4) may help them to relax their restricted diet5-8. While BH4 treatment can support normal growth, a decreased intake of protein substitute may cause deficiency of certain micronutrients9,10.

Protein substitutes play an essential role in the dietary management of PKU. They provide safe protein, key nutrients, and have an important role to play in metabolic control. With all new pharmaceutical adjunct therapies for PKU, the long-term impact of lowering protein substitute dosage on dietary intake and overall nutritional status should be carefully monitored.

Professor Anita MacDonald, Birmingham Children’s Hospital

A recent systematic review and meta-analysis on the protein requirements of patients with PKU on BH4 treatment shows that even when BH4 therapy works, almost half of this subset of PKU patients still needs a protein substitute to meet their protein requirements and achieve good metabolic control11. In any situations where protein requirements are increased (e.g., rapid growth, illness, or pregnancy), it is particularly important to evaluate whether an increase in prescription or re-introduction of protein substitute is necessary.

This new scientific research, along with many other exciting topics, will be presented at this year’s International Congress of Inborn Errors of Metabolism (ICIEM).

Nutricia has developed a broad range of inherited metabolic disorder (IMD) products, supporting as many people with IMDs as possible across a variety of conditions, across the world. We use our unique nutritional expertise to develop high-quality products that help make the lives of patients and their families a little easier.

Learn more about Nutricia’s presence at ICIEM and register now.

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