3‐Methylglutaconic aciduria type I: Clinical heterogeneity as a neurometabolic disease

Abstract
3‐Methylglutaconic (3‐MGC) aciduria with 3‐methylglutaconyl‐CoA hydratase deficiency (3‐MGC aciduria type I) is a rare inherited metabolic disease of L‐leucine catabolism. We describe a 9‐month‐old Japanese boy with this disorder who showed progressive neurological impairments presented as quadriplegia, athetoid movements and severe psychomotor retardation from 4 months of age. This finding indicates the existence of clinical heterogeneity in 3‐MGC aciduria type I, suggesting it may present as a neurometabolic disease.