Supplementary Material for: Purtscher-like retinopathy with renal impairment: a case report and review of the literature

Introduction Purtscher-like retinopathy (PLR) is a rare retinal vasculopathy characterized by acute vision loss. It is typically associated with systemic diseases such as renal impairment. The combined incidence of Purtscher retinopathy (PuR) and PLR is estimated at 0.24 cases per million annually. The hallmark of PLR is sudden-onset visual acuity reduction accompanied by retinal findings, including Purtscher-flecken, hemorrhages, and cotton-wool spots. Case Presentation We report a 46-year-old male with a history of chronic hypertension, dyslipidemia, cryoglobulinemia, and multiple viral infections, presenting with sudden bilateral vision loss. Fundoscopy revealed retinal swelling, hemorrhages, and exudation. Laboratory findings indicated impaired renal function (eGFR by CKD-EPI Cr 19 mL/min/1.73 m²), cryoglobulinemia, and signs of chronic kidney disease. A renal biopsy confirmed membranoproliferative glomerulonephritis with immune complex deposition. The patient was treated with corticosteroids, therapeutic apheresis, and supportive care. Visual acuity partially improved in one eye during hospitalization. Conclusion PLR is a rare condition often linked to systemic diseases such as renal failure. Its pathophysiology involves retinal microvascular damage, potentially mediated by complement activation. Diagnosis is based on characteristic fundoscopic findings and associated systemic conditions. Corticosteroids remain the most commonly used treatment, although evidence for their efficacy is limited. This case highlights the rare overlap between PLR and renal impairment, emphasizing the importance of early recognition and multidisciplinary management. Further research is needed to elucidate the pathophysiology and optimize treatment protocols for PLR.