Eyes See what the Mind Knows: Clues to Pattern Recognition in Single Enzyme Deficiency-Related Peroxisomal Disorders

Abstract

• Disorders of peroxisomes include inherited defects of peroxisomal biogenesis as well as few single enzyme defects. • Acyl CoA oxidase (ACOX1) and D-bifunctional protein (DBP) deficiencies are 2 single enzyme defects in the beta-oxidation pathway of very long-chain fatty acids. Clinical profile of the patients is similar to peroxisomal biogenesis disorders, with some biochemical and radiological differences. Novel Insights • ACOX1 and DBP deficiencies not only show similarity in the clinical presentation, but also in facial dysmorphology and neuroradiological features. • A clinically recognizable facial phenotype and a strikingly similar radiological profile (MRI pattern) can help identify cases of ACOX1 and DBP deficiencies earlier. • Expansion of the genotypic spectrum with a description of 3 homozygous novel mutations (HSD17B4: c.670C>T, c.1807T>C; ACOX1: 1.03-kb exonic deletion).