Primary CoQ 10 deficiency with a severe phenotype due to the c.901 C > T (p.R301W) mutation in the COQ8A gene.

Primary Coenzyme Q deficiency should be considered in patients presenting with autosomal recessive stable-appearing progressive ataxia, emerging attacks of status epilepticus, stroke-like lesions on neuroimaging, and cardiomyopathy. Since there is a case with the same mutation with a similar fatal course in the literature, detection of c.901 C > T (p.R301W) mutation homozygously should be a warning for a severe prognosis and more aggressive treatment should be started without delay with a high dose of CoQ instead of the lower doses used in the treatment of mitochondrial disease.