maple syrup urine disease

noun

ma·​ple syr·​up urine disease ˈmā-pəl-ˈsər-əp-, -ˈsir-əp- 

: an inherited disorder of amino acid metabolism that is characterized initially by an odor of maple syrup in the urine and in earwax and by vomiting, fatigue, irritability, and hypertonicity, and that unless treated with dietary measures leads to seizures, brain damage, coma, and death

Note: Maple syrup urine disease is caused by a deficiency of the enzyme decarboxylase, which leads to high concentrations of the amino acids valine, leucine, isoleucine, and alloisoleucine in the blood, urine, and cerebrospinal fluid. The disorder is inherited as an autosomal recessive trait requiring that both parents pass on a copy of the defective gene on a chromosome other than a sex chromosome.