LOCALIZED PROTON MAGNETIC-RESONANCE SPECTROSCOPY IN X-LINKED ADRENOLEUKODYSTROPHY

We have performed localised proton magnetic resonance spectroscopy (MR S) of the brain on four patients with X-linked adrenoleukodystrophy (X -ALD). The spectrum is characterised at the beginning of the disease b y a decrease in N-acetylaspartate and phosphocreatine-creatine content . Choline is strongly increased, and lactate can be detected in some c ases. A proton signal from the CH2 groups borne by free intracellular very long chain fatty acids can also be observed. Later in the disease , the levels of all metabolites, in particular NAA, decrease significa ntly. The progression of neurometabolism documented by MRS correlates well with MRI and clinical progression on follow-up study. In one case , the metabolic profile recorded by proton MRS was abnormal before any change occurred on MRI. Proton MRS of the brain might be the method o f choice for monitoring patients with X-ALD, to screen presumed cases and to study the effects of treatment.