Maple Syrup Urine Disease (MSUD) is a rare inherited metabolic disorder that affects the body's ability to process certain amino acids. The condition is named for the distinctive sweet odor of the urine, reminiscent of maple syrup. MSUD is caused by a deficiency in the enzyme complex known as branched-chain alpha-keto acid dehydrogenase (BCKD), which is necessary for breaking down the amino acids leucine, isoleucine, and valine.
