Dear Editor,
We went through the article titled “Retinal manifestations of ophthalmic artery occlusion with ischemic stroke in a young patient with COVID-19” by Paul L et al.[1] The authors have reported a case of ophthalmic artery occlusion with ischemic stroke in a patient with coronavirus disease 2019 (COVID-19) infection. The authors have mentioned that following extensive workup, the patient had increased prothrombin time, hyperlipidemia and hyperhomocysteinemia. Following this, the patient was started on anti-hypertensive, lipid lowering agents and anti-platelet drugs. The patient had multiple risk factors which could individually lead to an ischemic stroke. Hypertension and deranged lipid profile are well-known risk factors associated with stroke and retinal vascular disorders. Raised serum homocysteine levels have been reported to be associated with vascular occlusions.[2,3] Possible mechanisms of thrombosis induced by raised serum homocysteine levels include endothelial toxicity, promotion of smooth muscle proliferation, intimal thickening, increased platelet adhesion, activation of factor V, and decreased production of nitric oxide and prostacyclin. COVID-19 infection can still be a plausible precipitating factor in an otherwise predisposed person with other risk factors. Though the patient had COVID-19 infection in the present case, the association seems to be more coincidental.
Potential mechanisms of COVID-19-induced thrombosis include a dysregulated immune response, endothelial dysfunction, oxidative stress damage and dysregulation of the renin–angiotensin–aldosterone pathway.[4] Suggestive laboratory markers of disseminated intravascular coagulation induced by COVID-19 infection include raised D-dimer levels, prolonged prothrombin time and thrombocytopenia.[5] The authors have not mentioned if the D-dimer levels were elevated in their case. It will also be helpful to know if the patient had been started on vitamin supplements containing vitamin B12, B6 and folic acid to reduce serum homocysteine levels. As the patient presented three months after COVID-19 infection, serum homocysteine could have been measured to check if the levels had returned to normal or were still elevated.
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References
- 1.Paul L, Jain T, Singh S. Retinal manifestations of ophthalmic artery occlusion with ischemic stroke in a young patient with COVID-19. Indian J Ophthalmol. 2022;70:1415–7. doi: 10.4103/ijo.IJO_2828_21. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Panigrahi PK, Samant S, Dhar SK. A rare case of bilateral superior ophthalmic vein thrombosis presenting simultaneously with central retinal vein occlusion and cerebral venous sinus thrombosis. Indian J Ophthalmol Case Rep. 2022;2:229–31. [Google Scholar]
- 3.Cahill M, Karabatzaki M, Meleady R, Refsum H, Ueland P, Shields D, et al. Raised plasma homocysteine as a risk factor for retinal vascular occlusive disease. Br J Ophthalmol. 2000;84:154–7. doi: 10.1136/bjo.84.2.154. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Ali MAM, Spinler SA. COVID-19 and thrombosis:From bench to bedside. Trends Cardiovasc Med. 2021;31:143–60. doi: 10.1016/j.tcm.2020.12.004. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Gómez-Mesa JE, Galindo-Coral S, Montes MC, Muñoz Martin AJ. Thrombosis and coagulopathy in COVID-19. Curr Probl Cardiol. 2021;46:100742. doi: 10.1016/j.cpcardiol.2020.100742. doi:10.1016/j.cpcardiol. 2020.100742. [DOI] [PMC free article] [PubMed] [Google Scholar]