Rapid diagnosis of medium-chain acyl CoA dehydrogenase deficiency by measurement ofcis-4-decenoic acid in plasma

Abstract
Plasma concentrations of octanoate andcis-4-decenoate were measured by gas chromatography-mass spectrometry in children with deficiencies of medium-chain acyl-CoA dehydrogenase (MCAD), long-chain 3-hydroxyacyl-CoA dehydrogenase (3LHAD) and multiple acyl-CoA dehydrogenase (MAD) deficiency. Children receiving medium- and long-chain lipid supplements were also studied. Octanoate was elevated in all but one of the children with MCAD deficiency, in MAD deficiency and in children receiving medium-chain triglyceride supplementation.Cis-4-decenoate was only elevated in MCAD and MAD deficiency. It is concluded that measurement of plasmacis-4-decenoate provides a sensitive and specific test for defects of medium-chain acyl CoA dehydrogenase.