Prospective Study of Maple-Syrup-Urine Disease for the First Four Days of Life

Maple-syrup-urine disease, also known as branched-chain ketoaciduria, results from a primary defect in oxidative decarboxylation of the ketoacids derived from the branched-chain amino acids leucine, isoleucine, and valine. 1 Neonates with the most common form of this autosomal recessive disorder (classic maple-syrup-urine disease) appear normal at birth but usually become symptomatic by four or five days of age, with lethargy, poor appetite, vomiting, and alternating periods of hypertonicity and flaccidity. Progressive neurologic deterioration, seizures, coma, and acidosis ensue; death may occur within 10 to 14 days if the condition is untreated. 2 Delay in diagnosis or improper treatment results in mental retardation . . .