CRVO associated with COVID-19 and MTHFR mutation in a 15-year-old male

PURPOSE: To report a case of a central retinal vein occlusion (CRVO) associated with COVID-19 in a patient predisposed to clotting due to a genetic mutation in methylenetetrahydrofolate reductase (MTHFR). OBSERVATIONS: A 15-year-old male presented with 1 day of painless blurry vision in the left eye. Exam disclosed trace anterior chamber cell, anterior vitreous cell, optic nerve head edema, temporally displaced macular star, dilated tortuous veins, and diffuse intraretinal hemorrhages. Exam and FA was consistent with CRVO, however the macular star and OCT were suggestive of a neuroretinitis. The patient then presented to a children's hospital for further evaluation. A routine screen for COVID-19 via nasopharyngeal swab was positive with a high viral load. He also had a known history of an MTHFR mutation. Extensive laboratory and neuroradiologic evaluation excluded other infectious, inflammatory, and coagulopathic etiologies. CONCLUSIONS AND IMPORTANCE: This is a case of CRVO associated with COVID-19 infection and an underlying systemic hypercoagulable mutation, with an initial presentation that mimicked neuroretinitis. This case provides valuable diagnostic learning points and expands our knowledge of possible ocular complications of COVID-19.