Diagnosis of peroxisomal disorders with neurological involvement

Peroxisomal disorders are a group of inherited metabolic diseases caused by impairment of one or more peroxisomal functions. Ten disorders with neurological involvement have been recognized. Diagnosis and differentiation of these disorders is based on a number of important biochemical markers. For all disorders elevated values of very long chain fatty acids (VLCFA) and/or phytanic acid (PHYT) are important primary diagnostic parameters. Our results with regard to these two diagnostic markers are presented. VLCFA determined by gaschromatography in 414 samples (plasma, leukocytes or fibroblasts respectively) revealed increased values of hexacosanoic acid in 30 hemizygotes and 10 heterozygotes of adrenoleukodystrophy/adrenomyeloneuropathy and in eight infants with Zellweger disease or neonatal adrenoleukodystrophy. 15 cases with peroxisomal disorders were detected by VLCFA analysis in autopsy material. Gaschromatographic analysis of PHYT in plasma showed in some patients with Zellweger disease or neonatal adrenoleukodystrophy increase. In seven Refsum patients beside gaschromatographic demonstration of PHYT accumulation in plasma, analysis of plasma phytanyltriglycerides by thin-layer chromatography proved to be a rapid and reliable method for detection of patients and monitoring dietary treatment.