Pyridoxine-Dependent Seizures: Magnetic Resonance Spectroscopy Findings

Abstract

Pyridoxine-dependent seizures are an extremely rare genetic disorder. Early diagnosis and treatment are important for the prevention of permanent brain damage. Elevated levels of glutamate and decreased levels of γ-aminobutyric acid (GABA) in the frontal and parietal cortices are among the characteristic features of this disorder. These metabolic abnormalities eventually lead to seizures and neuronal loss. In this case report, we present magnetic resonance spectroscopy findings of a 9-year-old girl with pyridoxine-dependent seizures with mental retardation. The N-acetyl-aspartate-to-creatine ratio was found to be decreased in the frontal and parieto-occipital cortices, which could indicate neuronal loss. Magnetic resonance spectroscopy could be a useful tool in the neuroimaging evaluation for assessment of parenchymal changes despite a normal-appearing brain magnetic resonance image in patients with pyridoxine-dependent seizures. (J Child Neurol 2004;19:75—78).

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