COQ6 Mutations in Children With Steroid-Resistant Focal Segmental Glomerulosclerosis and Sensorineural Hearing Loss

Eujin Park; Yo Han Ahn; Hee Gyung Kang; Kee Hwan Yoo; Nam Hee Won; Kyoung Bun Lee; Kyung Chul Moon; Moon-Woo Seong; Tae Rin Gwon; Sung Sup Park; Hae Il Cheong

doi:10.1053/j.ajkd.2016.10.040

COQ6 Mutations in Children With Steroid-Resistant Focal Segmental Glomerulosclerosis and Sensorineural Hearing Loss

Am J Kidney Dis. 2017 Jul;70(1):139-144. doi: 10.1053/j.ajkd.2016.10.040. Epub 2017 Jan 20.

Authors

Eujin Park¹, Yo Han Ahn¹, Hee Gyung Kang², Kee Hwan Yoo³, Nam Hee Won⁴, Kyoung Bun Lee⁵, Kyung Chul Moon⁶, Moon-Woo Seong⁷, Tae Rin Gwon⁸, Sung Sup Park⁷, Hae Il Cheong⁹

Affiliations

¹ Department of Pediatrics, Seoul National University Children's Hospital, Seoul, Korea.
² Department of Pediatrics, Seoul National University Children's Hospital, Seoul, Korea; Research Coordination Center for Rare Diseases, Seoul National University Hospital, Seoul, Korea.
³ Department of Pediatrics, Korea University Guro Hospital, Seoul, Korea.
⁴ Department of Pathology, Korea University College of Medicine, Seoul, Korea.
⁵ Department of Pathology, Seoul National University Hospital, Seoul, Korea.
⁶ Department of Pathology, Seoul National University Hospital, Seoul, Korea; Kidney Research Institute, Medical Research Center, Seoul National University Hospital, Seoul, Korea.
⁷ Department of Laboratory Medicine, Seoul National University Hospital, Seoul, Korea; Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea.
⁸ Department of Laboratory Medicine, Seoul National University Hospital, Seoul, Korea.
⁹ Department of Pediatrics, Seoul National University Children's Hospital, Seoul, Korea; Research Coordination Center for Rare Diseases, Seoul National University Hospital, Seoul, Korea; Kidney Research Institute, Medical Research Center, Seoul National University Hospital, Seoul, Korea. Electronic address: cheonghi@snu.ac.kr.

PMID: 28117207
DOI: 10.1053/j.ajkd.2016.10.040

Abstract

The phenotypic combination of steroid-resistant focal segmental glomerulosclerosis (SR-FSGS) and sensorineural hearing loss has been mainly reported in patients with mitochondrial cytopathies, including primary coenzyme Q10 (CoQ10) deficiency. In this report of 10 children with SR-FSGS and sensorineural hearing loss, we found 6 patients with biallelic COQ6 mutations. Median age at the onset of nephrotic syndrome was 29 (range, 15-47) months. All patients progressed to end-stage renal disease within a median of 13 (range, 1-27) months after the onset. Kidney biopsy revealed abnormal mitochondrial proliferation in podocytes in all 6 patients. None of the 5 patients who underwent kidney transplantation developed recurrence of FSGS. Primary CoQ10 deficiency due to COQ6 mutations should be considered in children presenting with both SR-FSGS and sensorineural hearing loss. An early diagnosis of COQ6 mutations is essential because the condition is treatable when CoQ10 supplementation is started at the early stage. We recommend early kidney biopsy because detection of abnormal mitochondrial proliferation in podocytes might provide an earlier diagnostic clue.

Keywords: COQ6 mutation; Steroid-resistant focal segmental glomerulosclerosis (SR-FSGS); case report; children; coenzyme Q10 deficiency; end-stage renal disease (ESRD); kidney biopsy; mitochondrial cytopathy; mitochondrial proliferation in podocytes; pediatric; sensorineural hearing loss.

Publication types

Case Reports

MeSH terms

Child, Preschool
Female
Glomerulosclerosis, Focal Segmental / complications
Glomerulosclerosis, Focal Segmental / genetics*
Glomerulosclerosis, Focal Segmental / pathology
Hearing Loss, Sensorineural / complications
Hearing Loss, Sensorineural / genetics*
Humans
Infant
Male
Mutation*
Ubiquinone / genetics*

Substances

ubiquinone 6
Ubiquinone