IN-VIVO PROTON MAGNETIC-RESONANCE SPECTROSCOPY OF THE BRAIN IN A PATIENT WITH L-2-HYDROXYGLUTARIC ACIDEMIA

Morphologic appearance and metabolic disturbances of the brain of a pa tient with L-2-hydroxyglutaric acidemia were investigated with use of magnetic resonance imaging and localized proton magnetic resonance spe ctroscopy in vivo. Whereas magnetic resonance imaging revealed increas ed internal and external cerebrospinal fluid spaces as well as patchy white matter lesions, metabolic deviations included a 50% decrease of N-acetylaspartate (neuronal marker), a 75% increase of myo-inositol (g lial marker), and a 40% decrease of choline-containing compounds in wh ite matter relative to age-matched controls. A clinical deterioration of the patient was clearly reflected in a follow-up examination 22 mo later, resulting in a further reduction of N-acetylaspartate and a mor e pronounced enhancement of myo-inositol. No elevation of lactate was observed. The magnetic resonance spectroscopy findings are in line wit h a generalized neurodegenerative process in L-2-hydroxyglutaric acide mia but also suggest a defect in phosphatidyl inositol metabolism of g lial cells.