Treating MSUD


Children diagnosed with MSUD are first referred to a specialist metabolic dietitian and given a low-protein diet. This is tailored to reduce the amount of amino acids your baby receives, especially leucine, valine and isoleucine.

High-protein foods need to be limited, including:

  • meat
  • fish
  • cheese
  • eggs
  • pulses
  • nuts

Your dietitian will provide detailed advice and guidance, as your baby still needs some of these foods for healthy growth and development.

Some children need to take supplements of isoleucine and valine alongside the prescribed diet. This is to help maintain a healthy level of these amino acids in the blood without causing harm. Blood tests are needed to monitor these levels.

Breastfeeding and baby milk also need to be monitored and measured, as advised by your dietitian. Regular baby milk contains the amino acids that need to be restricted, so a special formula is used instead. This contains all the vitamins, minerals and other amino acids your baby needs.

People with MSUD need to follow a low-protein diet for the rest of their life to reduce the risk of a metabolic crisis. As your child gets older they'll eventually need to learn how to control their diet and will stay in contact with a dietitian for advice and monitoring.

Emergency treatment

If your baby develops an infection, such as a high temperature or cold , their risk of having a metabolic crisis increases. It's possible to reduce the risk by changing to an emergency diet while they're ill.

Your dietitian will provide detailed instructions, but the aim is to replace milk and foods containing protein with special high-sugar drinks and amino acid supplements.

If your baby can't keep down their emergency feeds or has repeated diarrhoea , contact the metabolic team at the hospital to let them know you're heading straight to the accident and emergency (A&E) department .

You should also be givena leaflet to bring with you in the event of an emergency in case the doctors haven't seen MSUD before.

Once in hospital, your baby can be monitored and treated with fluids given directly into a vein (intravenous fluids).

You should also take your baby to hospital if they develop the symptoms of a metabolic crisis, such as irritability, loss of energy or breathing difficulties.

Liver transplant

A liver transplant is sometimes an option to treat MSUD. If a person with MSUD receives a donated liver, they'll no longer be at risk of a metabolic crisis and can have a normal diet.

However, a liver transplant is a major procedure with its own risks. You will have to takemedicine to suppress the immune system (immunosuppressant medication)for the rest of your life to stopyour body rejecting the new liver.

It's important to consider all the pros and cons before deciding whether or not to have a liver transplant. Your doctor will be able to discuss whether this is a suitable option.

Content supplied by the NHS Website

Medically Reviewed by a doctor on 21 Dec 2018