Maple syrup urine disease is a severe inborn error of amino acid metabolism caused by deficiency of the mitochondrial branched-chain alpha-ketoacid dehydrogenase complex (BCKDC) resulting in the accumulation of branched-chain amino acids (BCAA) (isoleucine, leucine, and valine) and their corresponding branched-chain alpha-ketoacids (BCKA) [alpha-keto-beta-methylvalerate (KMV), alpha-ketoisocaproate (KIC), and alpha-ketoisovalerate(KIV)] in tissues and plasma. The disorder typically manifests with potentially lethal episodes of intoxication presenting with acute neurological deterioration, feeding problems, weight loss, and a maple syrup odor to the urine. Current treatment is based on dietary manipulations with protein restriction and a synthetic formula with reduced BCAA content. However, mental and social impairment are still present in the majority of these patients in spite of dietary management.