A rare case of primary coenzyme Q10 deficiency due to COQ9 mutation

Olgac A., Öztoprak Ü., Kasapkara Ç. S., Klllç M., Yüksel D., Derinkuyu E. B., ...More

Journal of Pediatric Endocrinology and Metabolism, vol.33, no.1, pp.165-170, 2020 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 33 Issue: 1
  • Publication Date: 2020
  • Doi Number: 10.1515/jpem-2019-0245
  • Journal Name: Journal of Pediatric Endocrinology and Metabolism
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, CAB Abstracts, EMBASE, MEDLINE
  • Page Numbers: pp.165-170
  • Keywords: cardiomyopathy, COQ9 gene, epilepsy, primary coenzyme Q10 deficiency
  • Lokman Hekim University Affiliated: No


© 2020 Walter de Gruyter GmbH, Berlin/Boston.Coenzyme Q10 (CoQ10) serves as a shuttle for electrons from complexes I and II to complex III in the respiratory chain, and has important functions within the mitochondria. Primary CoQ10 deficiency is a mitochondrial disorder which has devastating effects, and which may be partially treated with exogenous CoQ10 supplementation. A 9-month-old girl patient was referred to our clinic due to growth retardation, microcephaly and seizures. She was the third child of consanguineous parents (first-degree cousins) of Pakistani origin, born at 38 weeks gestation, weighing 2000 g after an uncomplicated pregnancy, and was hospitalized for 3 days due to respiratory distress. She had sustained clonic seizures when she was 4 months old. Physical examination showed microcephaly, truncal hypotonia and dysmorphic features. Metabolic tests were inconclusive. Abdominal ultrasonography revealed cystic appearance of the kidneys. Non-compaction of the left ventricle was detected in echocardiography. Cranial magnetic resonance imaging (MRI) showed hypoplasia of the cerebellar vermis and brain stem, corpus callosum agenesis, and cortical atrophy. A panel testing of 450 genes involved in inborn errors of metabolism (IEM) was performed that showed a novel frameshift c.384delG (Gly129Valfs*17) homozygous mutation in COQ9. A treatment of 5 mg/kg/day exogenous CoQ10 was started when she was 10 months old, and the dosage was increased to 50 mg/kg/day after the exact diagnosis. No objective neurological improvement could be observed after the adjustment of the drug dosage. We report a case of CoQ10 deficiency due to a novel COQ9 gene mutation that adds clinical data from a newly diagnosed patient. Our case also outlines the importance of genetic panels used for specific diseases including IEM.