Rapidly Progressive Hydroxychloroquine Retinal Toxicity Presenting With Cystoid Macular Edema and Retinal Vasculopathy: A Novel Phenotype With 6-Year Follow-Up

Purpose: To report a unique case of hydroxychloroquine-associated retinal toxicity presenting with cystoid macular edema (CME) and retinal vasculopathy and to discuss its potential pathophysiology. Methods: A single case was reviewed. Case Report: A 65-year-old woman with a history of hydroxychloroquine use for approximately 5.5 years presented with bilateral CME and parafoveal ellipsoid zone disruption with outer retinal loss on optical coherence tomography. Multimodal imaging demonstrated central bull’s-eye maculopathy and peripheral pigmentary changes on fundus autofluorescence and peripheral vascular leakage on fluorescein angiography. The uveitis workup, anti-retinal antibody testing, and genetic testing were negative. As retinal findings were normal at the first hydroxychloroquine screening, the patient was diagnosed with advanced hydroxychloroquine toxicity. Conclusions: This case expands the phenotypic spectrum of hydroxychloroquine retinal toxicity to include CME associated with retinal vasculopathy. Annual retinal examination should begin promptly in patients receiving hydroxychloroquine at doses exceeding 5 mg/kg/day.