Atypical COQ2-related retinopathy in identical twins with nephropathy mimicking intermediate uveitis

Gavrič, Ana Uršula (author), Volk, Marija (author), Kojc, Nika (author), Osredkar, Damjan (author), Meglič, Andrej (author), Šuštar Habjan, Maja (author), Kiraly, Peter (author), Jaki Mekjavić, Polona (author)

Purpose: To describe an atypical presentation of COQ2-related retinopathy in identical twins withnephropathy, mimicking intermediate uveitis with cystoid macular oedema (CMO). Methods: Retrospective case report. Results: A 33-year-old man presented with bilateral vision worsening and suspected intermediate uveitis.Examination revealed vitreous cells, CMO, retinal microangiopathy, and severely abnormal electrooculo-graphy (EOG) with only borderline full-field electroretinography (ERG) changes. CMO worsened withtopical corticosteroids but improved bilaterally after a single unilateral intravitreal bevacizumab injection,suggesting a systemic therapeutic effect. His identical twin exhibited very similar retinal and systemicfindings. Whole-exome sequencing identified a homozygous likely pathogenic COQ2 variant (c.683A >G), confirming primary coenzyme Q10 (CoQ10) deficiency type 1. Both twins also had nephropathyconsistent with focal segmental glomerulosclerosis (FSGS) but no neurological involvement. Conclusions: This report expands the phenotypic spectrum of COQ2-related retinopathy, characterizedby retinal microangiopathy, CMO, and primary retinal pigment epithelium (RPE) dysfunction with pre-served rod function, in contrast to the typical retinitis pigmentosa–like phenotype. Recognition of thispresentation is critical, as early CoQ10 supplementation may stabilize disease progression and preventsystemic complications. Genetic testing should be considered in young patients with CMO resemblingintermediate uveitis, particularly when associated with nephropathy.

• Language: English
• Keywords: COQ2-related retinopathy, uveitis, rare disease
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: MF - Faculty of Medicine
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: Str. 1200-1205
• Numbering: Vol. 34, iss.5
• PID: 20.500.12556/RUL-185610
• UDC: 617.7
• ISSN on article: 1744-5078
• DOI: 10.1080/09273948.2026.2679855
• COBISS.SI-ID: 279820803
• Publication date in RUL: 13.08.2026

Record is a part of a journal

• Title: Ocular immunology and inflammation
• Shortened title: Ocul. immunol. inflamm.
• Publisher: Taylor & Francis
• ISSN: 1744-5078
• COBISS.SI-ID: 521279769

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• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.