[L-2-hydroxyglutaric aciduria: clinical, biochemical and neuroradiological findings in two Venezuelan patients].

INTRODUCTION

L-2-hydroxyglutaric aciduria is a rare inborn error of metabolism, autosomal recessive, identified in about 50 patients. The primary defect is still unknown. The clinical phenotype is variable. Affected individuals show slowly progressive neurodegenerative disorder with cerebellar ataxia and mental retardation. Pyramidal, and extrapyramidal signs, seizures and macrocephaly have been reported. All patients previously described show a pattern of subcortical leukoencephalopathy with nearly empty gyral cores and cerebellar atrophy in neuroimaging studies. The diagnosis is established by detection of increased levels of L-2-hydroxyglutaric acid in urine, plasma and cerebrospinal fluid.

CASE REPORTS

We here describe two patients 7 and 9 years old, who presented psychomotor retardation, seizures, progressive cognitive deterioration, and pyramidal, extrapyramidal and cerebellar signs. Magnetic resonance scanning of the brain demonstrated a bilateral subcortical leukoencephalopathy pattern and areas of increased T2-weighted signal in the basal ganglia and cerebellar dentate nuclei. The analysis of organic acids in urine by gas chromatography/mass spectrometry showed elevated 2-hydroxyglutaric acid, 100% of it in the form of L enantiomer.

CONCLUSION

The diagnostic consideration is based on clinical findings and typical neuroimaging pattern and is established by detection of L-2-hydroxyglutaric acid in body fluids. Subcortical white matter loss is an important clue to diagnosis.