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.
Ozand et al. (1994) described five infants from three families, one Egyptian, two Yemeni, with ethylmalonic aciduria. All patients showed vascular and reticular lesions.The neurologic symptoms were indicative of a progressive pyramidal tract disease. Uine organic acids indicated increased excretion of ethylmalonic, methylsuccinic, glutaric, and adipic acids.
The Centre for Arab Genomic Studies Work Group (2006) conducted a retrospective study for metabolic disorders described at AlWasl Hospital in Dubai between 1997 and 2006. Only one case of ethylmalonic aciduria was observed in a 9-month-old Egyptian girl resident of the UAE.
In a retrospective analysis of IEMs diagnosed over a 12-year period (1998-2010) in a hospital in Lebanon, Karam et al. (2013) found 15 patients diagnosed with Glutaric Acidemia Type II. The median age of diagnosis was 2-months.
Joshi et al. (2002) carried out a retrospective analysis of patients born with inborn errors of metabolism in Oman between June 1998 and December 2000. Among 82 patients, only one was diagnosed with glutaric aciduria type II [CTGA Database Editor's note: Computed annual incidence rate is 0.8/100,000].
Al-Riyami et al (2012) reported on the types and patterns of IEMs encountered in a sample of 1100 high-risk neonates referred to SQU Hospital in Oman over a 10-year period (1998-2002). Glutaric Acidemia-II was detected in eight neonates (five males, three females), belonging to four families. Seven of the patients had a family history of the condition, while five had consanguineous parents.
Al-Shamsi et al. (2014) undertook a study to calculate the birth prevalence of IEMs among Emiratis in the UAE by taking into consideration all neonates born with an inherited metabolic condition at Tawam Hospital between 1995 and 2012. Glutaric Aciduria Type II was found to have a birth prevalence of less than 1.1-1.9 per 100,000.
[See: Egypt > Ozand et al., (1994)].