Zellweger syndrome - a lethal peroxisome biogenesis disorder.

Zellweger syndrome (ZS) is the severest variety of peroxisomal biogenesis disorder (PBD). This is a fatal hereditary, autosomal recessive disorder. It is characterized by the absence of peroxisomes in the cells which are essential for many metabolic functions especially beta oxidation of very long chain fatty acids (VLCFAs). We report the case of a female Saudi toddler. She presented with dysmorphism, profound hypotonia, psychomotor retardation, seizures, and loss of hearing and vision with findings of optic atrophy. Biochemical study revealed significantly elevated level of VLCFAs, cerotic acid and phytanic acid. She also had periventricular leukomalacia and abnormal electroencephalography results and a PEX 1 gene mutation. The clinical data and investigations were consistent with ZS. As it is fatal in early life, genetic counseling and prenatal diagnosis are thus crucial.