Progressive memory loss for one year and visual changes for three months

A 49-year-old Chinese male presented with memory loss and vision disturbances. Neurological examination revealed bilateral positive Babinski signs. Cognitive assessments showed cognitive impairments. Neuroimaging studies showed high-intensity signals on bilateral parietal lobes, occipital lobes, temporal lobes, the splenium of the corpus callosum, and pyramidal tracts. Plasma very long chain fatty acids (VLCFA) assay was ordered and demonstrated abnormally high concentrations of C26:0, and abnormally high ratios of C24:0 and C26:0 to C22:0. This diagnosis was also supported by the pathogenic mutation detected in the ACBD1 gene. There was no significant adrenal insufficiency, so replacement therapy was not initiated.