MSUD is a rare disorder in which a baby or child has a problem breaking down particular amino acids known as leucine, isoleucine and valine contained within protein. For people with MSUD, eating too much protein can cause a harmful build up of these amino acids in the blood.
What are the effects of having MSUD? Many babies with MSUD become unwell when they are a few days old, with:
- poor feeding
- vomiting
- excessive sleepiness
Without treatment, this leads to a coma and permanent brain damage. In older children a minor illness, such as a chest infection or a tummy upset, can lead to serious problems. The early signs in older children include confusion and poor balance as well as loss of appetite, vomiting and excessive sleepiness. As with babies, this can lead to a coma unless treated correctly.
These effects can be prevented if the disorder is identified and treated in the first few days of life which is why screening is strongly recommended.
How is MSUD treated? MSUD is treated with a special low protein diet which is used to prevent the build-up of harmful amino acids in the blood. Special supplements are needed as part of this diet, along with regular blood tests.
The following information leaflets are available for parents and can be downloaded from the UK newborn screening Programme website:
- MSUD is suspected https://www.gov.uk/government/publications/msud-suspected-description-in-brief
- MSUD confirmed diagnosis https://www.gov.uk/government/publications/msud-confirmed-diagnosis-description-in-brief