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Inherited metabolic disorders

Babies with these rare inherited disorders cannot process certain substances in their food. Without treatment, babies with these disorders will have serious long-term health problems and for some of the disorders babies can become suddenly and seriously ill.
 
Newborn screening means that babies who have one of these disorders can be identified early and have the right diet and treatment and specialist care to prevent health problems from developing.
 
It is very important to let your healthcare professional know if you have a family history of any of these metabolic disorders.
 
Babies are offered screening for the following six inherited metabolic disorders (IMDs):
 
Medium-chain acyl-CoA dehydrogenase deficiency (MCADD)
Babies with MCADD have problems breaking down fats to make energy for their body. If babies are not screened and have this disorder, the diagnosis may only be made when they become suddenly and seriously unwell. Three or four babies in Wales are born with MCADD each year.
 
Phenylketonuria (PKU)
Babies with PKU cannot break down an amino acid called phenylalanine. Amino acids are ‘building blocks’ of protein and we get protein from certain foods. If untreated, babies with PKU will develop a serious permanent mental disability. Newborn screening means that babies can be identified and treated with a special diet to prevent this disability.
Three or four babies in Wales are born with PKU each year.
 
Maple syrup urine disease (MSUD)
Isovaleric acidaemia (IVA)
Glutaric aciduria type 1 (GA1)
Homocystinuria (HCU)
 
Babies with MSUD, IVA, GA1 or HCU cannot break down certain amino acids that are contained in the protein we eat, in the usual way. This leads to harmful levels of certain amino acids and other harmful chemicals in the blood. These are rare disorders and it is expected that one or two babies in Wales will be born with one of these disorders each year.