When Newborn Screens Fail, Maple Syrup Urine Disease in a Toddler

Abstract

Introduction: Maple Syrup Urine Disease (MSUD) is a deficiency of branched-chain alpha-ketoacid dehydrogenase complex (BCKDC) which is one of the enzymes responsible for breaking down the amino acids leucine, isoleucine, and valine. This disease is included in all newborn screens in Mississippi and most other states. If the disease is allowed to follow its natural progression it will result in psychomotor delay, feeding problems, and the maple syrup odor of the urine that gives the disease its name. Classic MSUD usually presents with symptoms during the first few days of …