Managing the diet - MSUD

Tabel 4: Nutricia Metabolic formula characteristics Example
Product	MSUD Anamix
Form	Powder
Availability	400g/can
USE: Scoop or measurements
Recommended age	0-12 months or as a supplementary feed up to 3 years
Added vit/min	Yes
Protein equivalent
Carbohydrate
Fat
DHA
Fiber
Energy/kcal

Diet calculations of a newly diagnosed infant^1,2,3,4
Diagnosis	MSUD
Depending Plasma levels and clinical presentation at initiation: The main aim is to correct leucine levels between 80-200 µmol/l in the normal range as soon as possible	90 – 100% BCAA free infant formula; supplemented with ILE and VAL 0 – 20% breast milk or infant formula The BCAA source (breast milk of infant formula) is temporarily stopped and replaced by a BCAA free infant formula of 150 ml/kg/day, which will cause a rapid fall in LEU levels 75 – 90% BCAA free infant formula; 30 – 40% breastmilk or infant formula The breastmilk or standard infant formula is given by appr 50 mg/kg/day 25 – 50% BCAA free infant formula; 50 – 75 % breastmilk or infant formula
Protein recommendation	Age adequate, based on bodyweight Recommendation intake for leucine is 40-100 mg LEU/kg/day
Energy provision	Age adequate, based on bodyweight
Volume	Age adequate, based on bodyweght 6-8 feeds in 24 hours/on demand
BCAA free infant formula	Standard solution: 15 grams (or 3 scoops) BCAA free infant formula (MSUD Anamix Infant or MSUD 1-mix) + 90 mls water provides 100 ml BCAA free formula
Breast feeding	Mostly 6-8 feeds are advised daily. Mean LEU concentrations in breast milk = 1 mg/ml Techniques for breastfeeding Fixed frequency of breast feeding and PHE free formula alternating BCAA free formula prior to each breast feeding Measured expressed breast milk The volume will vary according to plasma levels, age of diagnosis and frequency of breast feeds.
Standard infant formula	Preparation of the standard infant formula as indicated. Mostly 6-7 feeds are advised daily, the total daily amount is divided by the amount of feeds. Techniques for bottle feeding Start with the standard infant formula feed to ensure the prescribed amount of BCAA is provided Mixing the standard infant formula with the BCAA free infant formula requires the infant need to finish the full amount and does not get used to the taste of the amino acids, which can be a problem once low protein foods are introduced and the standard infant formula amount is lowered. But it assures a balanced provision of essential amino acids
Frequency of monitoring	Plasma BCAA levels daily Reducing to 2-3 times a week Weighing: daily
Increasing BCAA intake	Increase amount of standard formula Or increase frequency of feeding or volume of breast milk
Transition to solid products/weaning	In line with recommendations on food introduction for healthy population Ensure total BCAA intake will stay in line with tolerance during introduction of protein containing solid foods Start the introduction on low protein foods gradually in line with local recommendations, like vegetables and fruits Provide the low protein foods after the breast milk or formula feeds Manage energy intake, low protein foods contain often lower energy density than breast or bottle feeds Once 8 – 12 tablespoons are consumed at one time, this can be given instead of the equivalent of the standard infant formula or breast feed Gradually introduce more texture and lumpier foods, starting at 6-8 months Finger foods can be introduced from 7 months onwards From 9 months the low protein pasta, low protein bread and potato (products) can be introduced

References

Dixon MD, MacDonald A, White F, Stafford J. In: Clinical Paediatric Dietetics. 4^th ed: West Sussex: John Wiley & Sons Limited, 2014:381-525.
GMDI: Nutrition Management guidelines for MSUD. https://southeastgenetics.org/ngp/guidelines.php.
Zweers-van Essen, H, Janssen-Regelink et al In: Dieet bij metabole ziekten. 1^st: WKZ/UMCU Utrecht. 2011;38-58
Knerr I, Vockley J, Gibson KM. Disorders of leucine, isoleucine and valine metabolism. In; Blau N (ed) Physician’s guide to the diagnosis, treatment and follow-up of inherited metabolic diseases