Multiple Acyl Co-A Dehydrogenase (MADD), also known as Glutaric Aciduria Type II is an autosomal recessively inherited inborn error of metabolism that results from a defect in the body's ability to properly process fats and proteins and produce energy. A severe neonatal form and a relativeley milder late onset form exist. Abnormalities in the level of urinary and serum metabolites, specifically, elevated levels of acylcarnitines, glutaric acid, and 2-hydroxyglutaric acid, are used to diagnose MADD.
MADD presents itself as a result of deficiency of several mitochondrial dehydrogenase enzymes that utilize Flavin Adenine Dinucleotide (FAD). These include the Electron Transfer Flavoproteins, ETFA and ETFB and Electron Transfer Flavoprotein Dehydrogenase, ETFDH.