Mitochondrial HMG–CoA Synthase Deficiency

The mitochondrial 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) synthase deficiency (MIM 600234) is an autosomic recessive inborn error of metabolism, hard to characterize and probably underdiagnosed (Thompson et al., 1997). The enzyme failure is caused by mutations in the gene HMGCS2, located in chromosome 1. The illness was first diagnosed in 1997 (Thompson et al., 1997), in a six-year old boy, who presented a semicomatose state after three days with gastroenteritis and diet (Bouchard et al., 2001). Up to date, only eight patients have been reported with an estimated incidence of