The 3-methylglutaconic acidurias (MGA) are a group of congenital metabolic disorders characterized by defects in mitochondrial function and excessive accumulation of 3-methylglutaconic acid and 3-methylglutaric acid. Five different types of MGA are known, all phenotypically differing from each other, and resulting from defects in different genes. MGA type I is typified by metabolic acidosis, psychomotor and speech delay, dystonia, spastic quadriparesis, seizures, basal gangliar atrophy, hepatomegaly, and severe hypotonia. Only about 20 cases of this condition have been reported worldwide.
Al-Arrayed (2006) indicated that 3-methylglutaric acidemia occurs in Bahrain at an approximate incidence of 2/10,000 births. (Al-Arrayed SS. Personal communication, Dubai, 2006.)
In a retrospective analysis of IEMs diagnosed over a 12-year period (1998-2010) in a hospital in Lebanon, Karam et al. (2013) found three patients diagnosed with 3-methyl glutaconic aciduria. one of these was through newborn screening. Mean age of diagnosis was 3.6-months.
Joshi et al. (2002) carried out a retrospective analysis of all patients born with inborn errors of metabolism in Oman between June 1998 and December 2000. Among the 82 patients, only one was diagnosed with 3 methylglutaconic aciduria [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). Methyl Glutaconic Aciduria was detected in two unrelated male neonates. One of the patients had a family history of the condition. Consanguinity was reported for one patient.
Al Aqeel et al. (1994) described 10 patients with 3-Methylglutaconic aciduria, including four who presented with early global neurologic involvement and arrested development.