Coenzyme Q10(CoQ10) is ubiquitously present in cells and plays a vital role in mitochondrial respiration. The COQ4 gene contains seven exons and resides on Chromosome 9. Mutations in exons 1-4 are linked with a subsequent onset and gradual advancement of CoQ10 treatment. In contrast, pathogenic mutations in exons 5-7 are said to cause earlier onset and mortality, plus an unfavourable response to CoQ10 treatment in these patients. A 2-years old boy patient first admission at 4 months old with febrile convulsions. He had refractory seizures and central hypotonia. Brain magnetic resonance imaging (MRI) of the patient revealed atrophy. MR spectroscopy highlighted deep inverted lactate peaks at 1.3 ppm and basal ganglia involvement. Echocardiography results were normal. As the patient continued to have seizures, failed to reach developmental milestones, had a history of consanguinity between parents, and had a sibling with Joubert syndrome, whole exome sequencing analysis was performed, revealing a homozygous mutation in COQ4/NM_016035/EXON5 c.437T>G p.(Phe146Cys). The family underwent segregation analysis, which revealed heterozygous mutations in both parents. High-dose CoQ10 therapy was initiated, and the patient was placed under follow-up with a diagnosis of primary CoQ10 deficiency. COQ4 deficiency is one of the rare causes of CoQ10 deficiency. Early detection and treatment can prevent the progression of this rare disease. In patients with the family history of recurrent seizures, hypotonia, developmental delay, cardiac abnormalities, visual and metabolic disorders, it is important to evaluate with advanced genetic tests for genetic disorders, especially CoQ10 deficiency, which is one of the treatable causes.

dilek türkmen
erciyes üniversitesi
Turkey

Mehmet Canpolat
erciyes üniversitesi
Turkey

Mücahid Besnek
erciyes üniversitesi
Turkey

Fatih Kardaş
erciyes üniversitesi
Turkey

MUNİS DÜNDAR
erciyes üniversitesi
Turkey