Maple Syrup Urine Disease

Maple syrup urine disease (MSUD) is a disorder of the branched-chain amino acids leucin, isoleucine, and valine and their corresponding keto-acids. Defective activity of the enzyme a-keto-acid dehydrogenase results in an accumulation of these amino acids and their keto-acids in the plasma, tissues, and CSF, and in their excretion in the urine. Leucin gives the characteristic maple syrup odor to urine.

The disease is inherited as an autosomal recessive trait. It manifests a few days after birth with vomiting, lethargy, myoclonic jerks, opisthotonus, episodes of apnea, and seizures progressing rapidly to coma and death. Edema, vacuolation, sponginess, and astrocytosis in the white matter are common cerebral findings. The brains of survivors show defective myelination and reduced numbers of oligodendrocytes.

0 0

Post a comment