Neurophysiologic follow-up of long-term dietary treatment in adult-onset adrenoleukodystrophy

Objective: To monitor the effects of dietary treatment in adult-onset adren oleukodystrophy (ALD) by means of somatosensory evoked potentials (SEPs) an d motor evoked potentials (MEPs). Background: SEPs and MEPs have proved use ful in revealing signs of progressively severe, central dying-back axonopat hy in early stages of adult-onset ALD. Methods: Eight patients with adult-o nset ALD underwent clinical examination, brain and spine MRI, and SEP and M EP studies before and after 3 years of Lorenzo's oil dietary therapy. Resul ts: Before treatment, brain MRI was normal in five patients. Three of these patients had pure spinal SEP abnormalities and in the remaining two patien ts SEPs showed signs of involvement of both the spinal and cerebral somatos ensory tracts. After treatment, the three patients with pure spinal abnorma lities showed clinical and neurophysiologic worsening, whereas the two pati ents with a more advanced stage of disease (exhibited by SEPs) showed subst antially unchanged clinical and neurophysiologic features. The patients wit h abnormal brain MRI at the onset of treatment showed clinical and neurophy siologic worsening. Conclusions: Lorenzo's oil therapy had no effect on pat ients with evidence of inflammatory brain lesions. Moreover, in patients wi thout clear signs of inflammatory damage, this treatment does not modify si gnificantly the natural course of the disease. However, because effective t reatments should begin before the onset of severe neurologic symptoms, SEPs and MEPs should be considered to evaluate the effectiveness of other exper imental treatments in the patient with a negative brain MRI.