Maple syrup urine disease (MSUD) is a rare autosomal-recessive disorder that affects branched-chain amino acid (BCAA) metabolism. It is characterized by accumulation of BCAAs and corresponding branched-chain keto acids of leucine, isoleucine, and valine in plasma, urine, and cerebrospinal fluid. Leucine is toxic to brain cells, leading to cytotoxic edema affecting the myelinated white matter, and involving the corticospinal tracts, thalami, globus palladi, midbrain, dorsal brain stem, and cerebellum. We present a neonate with the classic subtype of MSUD and its imaging features on magnetic resonance imaging.
Keywords: Branched-chain amino acids; magnetic resonance imaging; maple syrup urine disease; myelinated white matter; restricted diffusion.