Adrenoleukodystrophy: magnetic resonance follow-up after Lorenzo's oil therapy

To determine the therapeutic value of Lorenzo's oil (a mixture of glyceryl trioleate and glyceryl trierucate oils) in treating the childhood form of adrenoleukodystrophy (ALD), as indicated by magnetic resonance imaging (MRI) follow-up.

Between January 1992 and March 1994 eight males with biochemically proven ALD, ranging in age from 1 to 28 years, were referred for cerebral MRI and initiation of Lorenzo's oil dietary therapy; treatment continued for a period of 6 to 24 months. Five of the patients underwent follow-up cerebral MRI, and the images were reviewed without knowledge of medical status or chronology of imaging relative to therapy; the other three patients were excluded from the study because follow-up examinations were lacking. Signal abnormalities were evaluated according to a modified Loes scale, which yielded a minimum rating of 0 (for normal findings) and a maximum rating of 35 (for the most severe abnormalities). Because an untreated control group was not available for comparison, the Wilcoxon signed-rank test was used to analyse the results.

There was no statistically significant improvement in the ratings of abnormalities after treatment (p = 0.31, alpha = 0.10). However, the correlation between MRI findings and clinical symptoms was good.

The Wilcoxon signed-rank test is a useful statistical tool for evaluating the results of studies in which the sample population is small and there is no control group. The authors suggest that although Lorenzo's oil may not be curative, it may have a role in preventing the progress of ALD in asymptomatic patients. A multicentre control trial of Lorenzo's oil treatment, with emphasis on asymptomatic patients, is now underway.