Accumulation of very long chain fatty acids is common to 3 variants of adrenoleukodystrophy (ALD). "Classical" ALD, atypical ALD (female patient) and adrenomyeloneuropathy.

Fatty acids of cholesterol esters were analyzed by gas chromatography in affected CNS white matter of 3 variants of ALD ("classical" ALD, atypical ALD (adult female) and AMN) and of 10 controls with myelin breakdown of an etiology other than ALD. In all 3 ALD variants a marked accumulation of very long chain fatty acids (VLFA) as compared to control material was observed. This was due to the accumulation mainly of saturated C24-C32 fatty acids, particularly of C26:0, C25:0 and, to a lesser extent, C24:0 and C27:0 fatty acids. Our results demonstrate for the first time an accumulation of VLFA in an adult female patient (atypical ALD), who probably is an ALD heterozygote rather than a variant of AMN, and confirm and extend earlier findings in classical ALD and AMN, respectively. It appears that ALD may be a single nosological entity with clinically and morphologically different variants sharing specific ultrastructural (accumulation of paired leaflets) and neuro-biochemical (accumulation of VLFA) diagnostic markers.