DECREASED N-ACETYL-ASPARTATE CHOLINE RATIO AND INCREASED LACTATE IN THE FRONTAL-LOBE OF PATIENTS WITH HUNTINGTONS-DISEASE - A PROTON MAGNETIC-RESONANCE SPECTROSCOPY STUDY/

Background-Both the effect of the mutation and the pathogenesis of Hun tington's disease are unknown and a lack of biological markers for the natural history of the disease impedes the evaluation of novel therap eutic approaches. Methods-Proton magnetic resonance spectroscopy was c arried out on a frontal region of the cortex in 17 patients with clini cally overt Huntington's disease and four asymptomatic gene carriers. Results-Eight of 17 (47%) clinically affected patients with Huntington 's disease and each of the asymptomatic carriers had lactate peaks in the frontal cortex which were not present in controls. The N-acetyl-as partate/choline (NAA/Ch) ratio was significantly reduced in the sympto matic patients indicating the presence of neuronal loss. The reduction was related to the clinical severity of the disease and was absent in the asymptomatic carriers. Conclusion-The finding of lactate peaks su pports the hypothesis that disturbed cerebral energy metabolism contri butes to the pathogenesis of Huntington's disease.