Maple Syrup Urine Disease
- Maple syrup urine disease (MSUD) is an autosomal recessive metabolic disorder of branched chain amino acid metabolism. It results in abnormal accumulation of branched chain amino acids and metabolites within the serum, CSF, and urine.
- MSUD typically presents within the first week of life with lethargy, poor feeding, vomiting, and neurologic deterioration. Urine classically has a characteristic odor of maple syrup.
- Key Diagnostic Features: MR with diffusion-weighted imaging demonstrates characteristic edema/restricted diffusion within the cerebellar white matter, dorsal brainstem, corticospinal tracts, cerebral peduncles, posterior limb of internal capsules, thalami, and globi pallidi.
- DDx: Hypoxic-ischemic encephalopathy, toxic-metabolic encephalopathy
- Rx: Favorable outcome with lifelong strict dietary control
