An interesting case of metabolic dystonia: L-2 hydroxyglutaric aciduria

L-2-hydroxyglutaric aciduria (L-2-HGA), a neurometabolic disorder caused by mutations in the L-2 hydroxyglutarate dehydrogenase (L-2-HGDH) gene, presents with psychomotor retardation, cerebellar ataxia, extrapyramidal symptoms, macrocephaly and seizures. Characteristic magnetic resonance imaging findings include subcortical cerebral white matter abnormalities with T2 hyperintensities of the dentate nucleus, globus pallidus, putamen and caudate nucleus. The diagnosis can be confirmed by elevated urinary L-2 hydroxyglutaric acid and mutational analysis of the L-2-HGDH gene. We report two siblings with dystonia diagnosed by classical neuroimaging findings with elevated urinary 2 hydroxyglutaric acid. Riboflavin therapy has shown promising results in a subset of cases, thus highlighting the importance of making the diagnosis in these patients.