A simple method to diagnose adrenoleukodystrophy using a dried blood spot on filter paper.

A new, simple method for the diagnosis of adrenoleukodystrophy (ALD) using a dried blood spot sample, is described. Fatty acid from the dried blood spot was extracted and methylated simultaneously with HCl-methanol. Fatty acid methyl esters were analyzed by gas chromatography-mass spectrometry. Fatty acid compositions of the blood spot from four patients with ALD and five healthy controls were determined from the mass chromatograms of the m/z 143 ion, [(CH2)6 COOCH3]+. The ratios of tetracosanoic acid to docosanoic acid (C24:0/C22:0) and hexacosanoic acid to docosanoic acid (C26:0/C22:0) were significantly greater in ALD patients than in the controls. The fatty acid composition of the dried blood spot did not change at room temperature within a week. Since the specimens can be sent by mail, this method could be applied to the screening of ALD.