Infantile Refsum disease (IRD) is one of the less severe of Zellweger spectrum disorders (ZSDs), a group of peroxisomal biogenesis disorders resulting from a generalized peroxisomal function impairment. Increased plasma levels of very long chain fatty acids (VLCFA) and phytanic acid are biomarkers used in IRD diagnosis. Furthermore, an increased plasma level of phytanic acid is known to be associated with neuro...
Background Peroxisomal disorders are classified in two major groups: (1) Peroxisome Biogenesis Disorders and (2) single Peroxisomal Enzyme/Transporter Deficiencies. D-bifunctional protein deficiency (DBP; OMIM #261515) included in this last group of rare diseases leads to an impaired peroxisomal beta-oxidation. D-bifunctional protein deficiencies are classified in four types based on the degree of activity of t...