Maple Syrup Urine Disease (MSUD)


Maple Syrup Urine Disease (MSUD) is a condition in which the body is unable to break down certain proteins. The condition is named for the sweet odor of the urine of untreated babies. MSUD is considered an amino acid condition because people with MSUD have trouble breaking down certain amino acids, the building blocks of proteins. The most common form of MSUD begins in early infancy. Signs of MSUD include poor feeding, vomiting, lack of energy, and developmental delay. If untreated, MSUD can lead to seizures, coma, and death. Detecting MSUD early and beginning dietary and other treatment can often prevent the severe outcomes of the condition.

This condition is also known as: branched-chain alpha-keto acid dehydrogenase deficiency, branched-chain ketoaciduria, ketoacidemia, BCKD deficiency.

For more information about Maple Syrup Urine Disease, visit Screening, Technology, and Research in Genetics (STAR-G): Maple Syrup Urine Disease and Baby's First Test: Maple Syrup Urine Disease. Please see Medically Prescribed Formula for information about medically prescribed formula and pharmacologic interventions for inborn errors of metabolism. Visit Board Certified Metabolic Providers (PDF: 2 pages/204KB) for a listing of medical specialists and clinic contact information.