Definition: An autosomal recessive inherited disorder with multiple forms of phenotypic expression, caused by a defect in the oxidative decarboxylation of branched-chain amino acids (AMINO ACIDS, BRANCHED-CHAIN). These metabolites accumulate in body fluids and render a "maple syrup" odor. The disease is divided into classic, intermediate, intermittent, and thiamine responsive subtypes. The classic form presents in the first week of life with ketoacidosis, hypoglycemia, emesis, neonatal seizures, and hypertonia. The intermediate and intermittent forms present in childhood or later with acute episodes of ataxia and vomiting. (From Adams et al., Principles of Neurology, 6th ed, p936)
Other names Thiamine Responsive Maple Syrup Urine Disease; Branched-Chain Ketoaciduria; Ketoacidurias, Branched-Chain; Ketoaciduria, Branched-Chain; Branched-Chain Ketoacidurias; Branched Chain alpha Keto Acid Dehydrogenase Defic; Branched Chain Ketoaciduria; Maple Syrup Urine Disease, Thiamine Responsive; Maple Syrup Urine Disease, Intermittent; Maple Syrup Urine Disease, Intermediate; Maple Syrup Urine Disease, Classical; Maple Syrup Urine Disease, Classic; MSUD (Maple Syrup Urine Disease); Keto Acid Decarboxylase Deficiency; Intermittent Maple Syrup Urine Disease; Intermediate Maple Syrup Urine Disease; Classical Maple Syrup Urine Disease; Classic Maple Syrup Urine Disease; Branched-Chain alpha-Keto Acid Dehydrogenase Defic