Your diet

Principle behind the diet

The principle behind the diet is the same as for other hereditary disorders of protein catabolism disorders. You need to learn about it and understand it to implement it properly. (see your treatment guide). It has a number of specific elements:

  • Forbidden foods remain forbidden because of their high protein content;
  • Controlled foods are represented by infant formula (certain dairy products, depending on the child’s tolerance and, especially, age), fruits and vegetables, and they are quantified using an equivalence system chosen by the team of dietitians, such as valine equivalence or protein equivalence, knowing that 1 part of valine is 25 mg of valine (and 1 part of protein is 1 or 2 g of plant protein, depending on the healthcare centre).


During infancy, most natural protein intake (tolerance checked individually) will be in the shape of infant formula, particularly if enteral nutrition is needed.

  • It is better to use low-protein infant formula, since the daily protein allowance tends to be low. The rest is given in small meals of fruits and vegetables due to the child’s small appetite. Low protein foods can be given at will (although often in small amounts due to a lack of appetite). In order to provide enough calories, the diet will often be rounded out with maltodextrin and oil (or reconstituted sugar-fat products), which can be added to enteral nutrition.
    This will maintain the overall balance of foods and the intake of the various macronutrients and micronutrients (minerals, vitamins, trace elements) for the age of your child.
  • Your child may get a prescription for amino acids mixes without valine, isoleucine, methionine and threonine, but this is not always the case and depends on the age and laboratory results.
  • Continuous enteral nutrition with a nutrition pump is often required. It is usually managed by the parents at home.


Placing a gastric tube may seem aggressive, particularly for parents, even if you understand the critical importance of doing so. You will get help from the nurses in the unit before the first discharge and, if you want to, you will also get help from nurses at home. It is important to become autonomous quickly.


Gastrostomy can be considered in certain cases.

A service provider will get you a nutrition pump (and consumables: tubes, ports, feeding bags, syringes, etc.) based on the prescription issued by the attending physician. The service provider will come to your home to set it up and check it works properly together with you. Do not hesitate to ask this person for help! He or she is in contact with the care team at all times in the event of problems. The provider will also have a prescription for dietetic and medicinal treatments and will give you certain common nutrients. You will get enough nutrients (and consumables) for 28 days + special stock for emergencies, which will be reviewed at each delivery.

However, you are responsible for ordering hypoproteic foods from AGEPS! (if you live in France).



The treatment is restrictive and can sometimes seem difficult. From a medical perspective, regular metabolic control and proper monitoring help to prevent complications. Under regular conditions, monitoring will consist of

  • clinical assessments: weight, size, cranial perimeter and, of course, the clinical appearance of your child in frequent consultations (and during annual hospitalisation or day clinic, for more in-depth assessments);
  • urine samples to make sure metabolic balance is maintained;
  • Adjustment of the diet of your child based on the results of urine tests.


Furthermore, your child’s diet can be adjusted to reflect any changes in his or her feeding behaviour or appetite. Do not hesitate to contact your attendant physician or dietitian to keep them up-to-date so they can continue to guide you, or if you have any questions.

During high-risk periods for decompensation (e.g. when your child has a fever), make sure you are capable of doing the following:

  • Describing the clinical signs (fatigue with baggy eyes, apathy, gastrointestinal signs: nausea, vomiting, anorexia ++, neurological signs: lack of coordination, tremors, gait problems)
  • Carrying out a ketones urine test: it screens urine for ketone bodies and is an instantaneous marker of catabolism (it is done with a tablet or dipstick soaked in recent urine). The ketones urine test can be positive +, ++ or +++. Compare the colour with the set of standards.


Upon request of the referring physician, being able to take 24-hour urine samples for urine metabolite testing. Samples need to be taken adequately in order to be able to properly interpret the results. To do so, you need to collect urine samples every time your child urinates in a 24-hour period and keep the samples in the refrigerator. You must then bring these samples (on ice) to the laboratory of your healthcare centre. Some care teams may simply request a morning urine sample. Such an analysis takes much more time and can only be carried out in the specialised laboratory of the healthcare centre.

  • KNOW HOW TO ADJUST THE DIET: An emergency or semi-emergency diet will be given to you and described by the care team. The conditions triggering such a diet will also be explained. The aim of this diet is to avoid imminent metabolic decompensation in a high-risk situation. Some care teams prefer diet adjustments to be made only with their consent and after checking with them.


If you are worried, or if your child is not in normal condition, particularly if he or she has gastrointestinal problems, get in touch with the healthcare centre responsible for your child to get instructions on what to do, and do not be afraid to take your child to HOSPITAL; It is important not to wait too long before bringing your child to hospital.



The number and size of milk bottles will be adapted to the baby’s appetite and requirements, as well as tweaking the composition of enteral nutrition at night. That way, your child will get all the nutrients he or she needs to grow and gain weight like any other child.


Little children

Food diversification often occurs a bit later than with other children because a period of “recovery” is needed following the acute episode. However, you can introduce fruits and vegetables in the amounts prescribed by the doctor and dietitian and corresponding to the tolerance of your child, expresses in parts of valine or parts of protein. Be patient and do not get worried if your child is not very hungry or takes a long time to eat.

Do not force him or her to eat! If the prescribed quantities appear too big, talk it over with your doctor or dietitian, who may establish a different meal plan for your child. It is important to offer meals every day at the usual times, even if your child does not eat much. Like with any other child, try different textures to educate your child, e.g. with small pieces of raw fruits or vegetables.

Provide a variety of flavours, colours and presentations (even for very simple dishes, e.g. with purées modelled in different shapes). Do not give him or her “forbidden” foods, even in small quantities, thinking it will make your baby happy! This will only make compliance with the diet harder.

If you take your child with you when you go shopping, let him or her choose fruits and vegetables by naming them and guiding your child through the wide range of produce.

Let him or her get involved with cooking as soon as possible, and make it a game: this can spark the desire to taste things in your child and whet his or her appetite.

Do not keep your child away from parties!  He or she can share foods with the other children as long as he or she knows what to choose. This will help your child to gradually learn what he or she can eat to stay healthy.

RAISE AWARENESS of your child’s diet among people around you! It is important that your child can spend the afternoon with his or her grandparents or cousins once in a while.


Enteral nutrition:

Placing the nasogastric tube every night can be difficult: get your child involved so that he or she can take responsibility for the treatment. Some children may ask to place the tube “on their own” from an early age. Enteral nutrition may require a gastrostomy tube to replace the nasogastric tube. Your attending physician will explain this option.