Inborn errors of metabolism are based on genetic mutations, which impair the physiological functions of the cells.
Depending on the disrupted function, there can be an accumulation of the substrates that have not been metabolized, metabolites can be produced through alternative metabolic paths of these substrates, or result in reduced production or absence of the end products.
Phenylketonuria (PKU) is the most commonly inherited disorder that affects the metabolism of proteins.
PKU is due to the mutation of a gene that codifies phenylalanine hydroxylase
(PAH), the enzyme that metabolizes the amino acid phenylalanine into tyrosine, another amino acid.
The absence of phenylalanine hydroxylase prevents this reaction and may cause damage to the brain.
If identified at birth, early treatment allows for a normal development and prevents any compromise of the central nervous system. In addition to PKU, several other inherited metabolic diseases may include a treatment regime involving a low-protein diet.
A low-protein diet is the main treatment for many congenital metabolic diseases such as phenylketonuria (PKU).
The diet treatment, starting in the first days after birth and continued throughout a lifetime, promotes normal health and development in the child with PKU.
The dietary treatment of phenylketonuria is based on a diet that is low-protein/phenylalanine.
The diet limits their intake both from natural sources – meat, fish, dairy products etc.- and artificial sources, additives like Aspartame. It is therefore necessary to take dietary supplements, like amino acid mixtures, with a balanced content of minerals, vitamins, trace elements and amino acids – excluding Phe.