Peroxisomal acyl⁃CoA oxidase deficiency: one case report and literature review

Abstract

Objective To report a case of peroxisomal acyl⁃CoA oxidase (ACOX1) deficiency, which was caused by an unreported mutation of ACOX1 gene, and review its clinical characteristics. Methods and Results The male child patient suffered from neonatal hypotonia，developmental retardation and epilepsy seizure once since neonatal period. Neurodegeneration appeared at the age of 3 and developed rapidly to difficulty of sitting, standing and walking independently and retrogressive language expression ability. Physical examination showed special face, pyramidal tract sign and cerebellar signs. Cranial MRI revealed symmetric demyelinating lesions in bilateral brain stem and cerebellum along with increased serum very⁃long⁃chain fatty acids (VLCFAs). Whole exome sequencing revealed c. 1589A＞G (p. His530Arg) homozygous mutation in ACOX1 gene. His parents carried the same heterozygous mutation without symptoms and this phenomenon was in accord with co⁃segregation. According to the guidelines of American College of Medical Genetics and Genomics (ACMG), we considered this new variation to be possibly pathogenic variation. Finally, the patient was diagnosed as ACOX1 deficiency. Conclusions As for patients who suffer from hypotonia, epilepsy seizure and growth retardation since neonatal period, they should be altered to ACOX1 deficiency if cranial MRI shows symmetrical abnormal foci in cerebellum and brain stem. Positive family history, increased VLCFAs level, and gene detection would be beneficial to definite diagnosis.

doi：10.3969/j.issn.1672⁃6731.2021.04.009