Isovaleryl-CoA dehydrogenase deficiency

Isovaleric acidemia (isovaleryl-CoA dehydrogenase deficiency) WBC, FB 15ql4-ql5 243500... 

Therapeutic glycine. Isovaleric acidemia is an inherited disorder of leucine metabolism caused by a deficiency of isovaleryl CoA dehydrogenase. Many infants having this disease die in the first month of life. The administration of large amounts of glycine sometimes leads to marked clinical improvement. Propose a mechanism for the therapeutic action of glycine. 

Isovaleric acidemia (IVA) is a disorder of leucine catabolism caused by a deficiency of isovaleryl-CoA dehydrogenase. Since the initial report 40 years ago, IVA has been the main focus of the work of Dr. Kay Tanaka, one of the pioneers and arguably most productive contributors to our current... 

Isovaleric acidemia is a rare disorder of leucine metabolism caused by the deficiency of isovaleryl-CoA dehydrogenase this leads to mild neurological impairment and, at its severest, to coma and death. Dietary management aims to hmit leucine intake by means of a low-protein diet, and by supplementing the diet with a leucine-free amino acid mixture if necessary. 

IVA was initially described in 1966 and became the first organic acidemia described. IVA is caused by a deficiency of the enzyme isovaleryl-CoA dehydrogenase, an enzyme important in leucine catabolism and also important in the transfer of electrons to the respiratory chain [7, 13]. The consequent accumulating metabolites include isovaleric add, isovalerylglydne, 3-hydroxyisovaleric acid, and isovalerylcamitine (C5) [7, 13] (Fig. 17.3). These are easily identified on urine organic acid analysis and acylcamitine profile. The excretion of isovalerylglydne and 3-hydroxyisovaleric acid is diagnostic. 

The inborn errors of L-leucine catabolism present biochemically with branched-chain amino and/or organic aciduria [1]. These disorders include maple syrup disease (MSD branched-chain a-ketoacid dehydrogenase (BCKD) deficiency), isovaleric acidemia (isovaleryl-coenzyme A (CoA) dehydrogenase deficiency), isolated 3-methylcrotonyl-CoA carboxylase deficiency, the 3-methylglutaconic acidurias (3-methylglutaconyl-CoA hydratase deficiency, Barth syndrome, and other disorders in which the primary defect has not been demonstrated), and 3-hydroxy-3-methylglutaric aciduria (3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) lyase deficiency). 

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