Dietary Treatment of a Child with Maple Syrup Urine Disease (Branched-chain Ketoaciduria)

Maple syrup urine disease is one of a number of cerebro-degenerative conditions, which is caused, directly or indirectly, by a congenital defect in amino acid metabolism. However, in contrast to other diseases of a similar type, notably phenylketonuria, the affected children frequently die within the first month and the survivors rarely live for longer than two years (Menkes, Hurst and Craig, 1954). In 1957, Westall, Dancis and Miller reported that in this disease the blood and urine contained excessive amounts ofleucine, isoleucine, valine and methionine. This has since been confirmed in other cases, and it was further reported that the keto and hydroxy acid analogues of these amino acids were also