Maple syrup urine disease (branched-chain keto-aciduria) variant type manifesting as hyperkinetic behaviour and mental retardation: report of two cases

Abstract

Two siblings with a variant type of Maple Syrup Urine Disease have been presented. They had mental retardation with hyperkinetic behaviour and skin and hair changes. They partially resemble the variant of Maple Syrup Urine Disease recently reported by Schulman et al. (1970). The inheritance was compatible with an autosomal recessive mode. The atypical features in our cases have been stressed. It is postulated that a partial deficiency of the enzyme system responsible for the decarboxylation of keto acids and chronic low dietary intake of protein could explain the longevity of our patients. A plea has been made for recognition of milder and variant forms of the disease, probably quite common, by appropriate investigations of mentally deficient children.