Dengue fever case report: a red flag for retinal vein occlusion

Dengue is a prevalent arboviral infection in which ocular disease ranges from maculopathy and hemorrhage to vasculitis and retinal vascular occlusions, appearing during the acute phase or weeks later. Retinal vein and artery occlusions after dengue are uncommon but have been described in case reports and small series. Proposed mechanisms include thrombocytopenia with bleeding tendency, capillary leakage, and immune-mediated inflammation. The true frequency, risk factors, and patterns of bilateral or asymmetric ischemic involvement remain uncertain. We report serology confirmed mild dengue with hemiretinal vein occlusion (HRVO) in one eye and contralateral retinal nerve fiber layer ischemia in a patient without systemic comorbidities, expanding the recognized spectrum and underscoring the need for early ophthalmic assessment.

A 67-year-old male presented with sudden, painless vision loss in the right eye. The patient had a fever three days prior and was diagnosed with dengue fever (DF), confirmed by positive serology. Examination revealed macular edema and flame-shaped retinal hemorrhage in the right eye. Optical coherence tomography (OCT) disclosed ischemia of the retina nerve fiber layer in the left eye. The patient was treated with intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections in both eyes.

This case highlights the potential link between dengue infection and retinal vascular events, emphasizing the need for prompt recognition and management, in order to avoid ocular complications, visual impairment and blindness.