Inherited metabolic disease
Inherited metabolic disease (IMD) may present at any age and the signs and symptoms may result from:
• Accumulation of substrate that leads to a toxic effect.
• Accumulation of a minor metabolite that in excess is toxic.
• Deficiency of a product of a specific reaction.
• s metabolic phenomena.
The commonest error in managing infants and children with IMD is a delay in diagnosis, and therefore a delay in starting treatment. Failure to recognize an IMD may occur because its clinical features are confusing because of:
• Genetic heterogeneity.
• A presenting intercurrent illness.
• similarity with other common, acquired conditions where the differential diagnosis has not been fully explored.
A useful approach is to consider certain ‘syndromes’ and use this as a framework for investigation (Table 26.1).1 This approach is widely used and should serve the purpose.