Pediatric Nutrition in Practice

3 Nutritional Challenges in Special Conditions and Diseases

Key Words

Phenylketonuria · Maple syrup urine disease ·

Urea cycle disorders · Organic acidaemias ·

Galactosaemia · Glycogen storage disease · Protein ·

Amino acids · Galactose · Fructose · Glucose

Key Messages

• Common inborn errors of metabolism (IEM) treated
  by life-long dietary management are responsible
  for a collection of diverse clinical conditions


• It is essential to diagnose conditions before neuro-
  logical or other toxicological damage occurs


• Treatment strategies involve avoidance or con-
  trolled intake of dietary precursors of toxic meta-
  bolites in amino acid disorders, organic acidaemias,
  urea cycle disorders, galactosaemia and hereditary
  fructose intolerance


• Other disorders need to avoid prolonged fasting
  (e.g. fatty acid oxidation disorders) or a regular glu-
  cose supply (e.g. glycogen storage disorders)


• In IEM where acute metabolic decompensation oc-
  curs, the use of an emergency regimen is impera-
  tive


• Attentive nutritional support with the provision of
  macronutrients and micronutrients to meet dietary
  reference values/requirements is essential


• Frequent monitoring of growth, nutritional intake,
  development and biochemical control is necessary
  © 2015 S. Karger AG, Basel

Introduction

Common inborn errors of metabolism (IEM)

treated by life-long dietary management are re-

sponsible for a collection of diverse clinical con-

ditions. Each condition may present at different

ages with variable severity and outcome. Disor-

ders requiring avoidance of/reduction in dietary

precursors of toxic metabolites include phenyl-

ketonuria (PKU), maple syrup urine disease

(MSUD), organic acidurias, urea cycle disorders

(UCD) and galactosaemia. Disorders requiring

glucose stabilisation include fatty acid oxidation

defects and glycogen storage diseases (GSD). It

is essential to diagnose conditions before neuro-

logical or other toxicological damage occurs.

Many IEM are now recognised by newborn

screening programmes. In some conditions,

neonates may require emergency treatment

such as dialysis to remove toxic organic acids or

ammonia.

In IEM where acute metabolic decompensa-

tion occurs (precipitated by infections/surgery/

trauma combined with poor oral intake and fast-

ing), with risk of further irreversible damage,

particularly neurological, the use of an emergen-

cy regimen is imperative. An emergency regimen

provides an exogenous energy source (either

Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 226–233
DOI: 10.1159/000360344

3.16 Inborn Errors of Metabolism

Anita MacDonald