Nutrition in the management of inborn errors of metabolism

The determination of specific nutrients is important in the diagnosis of several inborn errors of metabolism. Phenylketonuria (PKU) is a well-known example. In this case, the nutrient, phenylalanine, is assayed to confirm a diagnosis and is routinely measured to monitor therapy, which consists of a diet low in this particular amino acid. Although many of the described inborn errors of metabolism are uncommon, or even rare, in occurrence, the laboratory plays an essential role in the diagnosis and management of these diseases.