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A Murine Model of Ischemic Retinal Injury Induced by Transient Bilateral Common Carotid Artery Occlusion
Published on: November 12, 2020
UNUSUAL CAUSE OF BRANCH RETINAL ARTERY OCCLUSION: POLYCYTHEMIA IN A TRANSGENDER MAN FROM UNREGULATED TESTOSTERONE USE
Darren Mun Yoong Choy1, Li-Wern Voon2, Stephen C B Teoh1,3
1National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore.
Purpose:
We report a transgender patient with branch retinal artery occlusion who had secondary polycythemia from unregulated testosterone injections and review the literature on the mechanisms of supraphysiologic and standard doses of testosterone causing a hypercoagulable state.
Methods:
Case report.
Results:
A 45-year-old Chinese transgender man with no medical history presented with a 1-week history of a scotoma in his left eye vision. Ophthalmologic examination revealed retinal pallor and edema along the superotemporal arteriole in the left eye. Optical coherence tomography showed increased thickness of the inner retinal layers of the superotemporal retina. Fluorescein angiography demonstrated an arm-retina time of 1 minute and 43 seconds, with no vascular sheathing and capillary fallout. A diagnosis of left superotemporal branch retinal artery occlusion was made. Initial blood tests revealed a hemoglobin level of 19.3 g/dL (11.8-14.6 g/dL), hematocrit of 62% (34.3-43.0%), and erythrocytes of 6.56 × 1012/L (3.7-4.8 × 1012/L). He revealed later that he had been on weekly testosterone injections (testosterone enanthate 250-mg depot injection) since 2011. He was also exposed to a moderately high altitude, when his symptoms occurred, raising the possibility of worsening hypercoagulability resulting in his thrombotic event.
Conclusion:
To the best of our knowledge, this is the first documented case of a trans man who developed branch retinal artery occlusion after self-administering supraphysiological doses of testosterone. In a young patient with no history of cardiovascular risk factors who develops retinal arterial occlusion, other causes such as hypercoagulable syndromes must be excluded. This case warns of the dangers of unregulated testosterone use, especially at supraphysiologic doses, and the risks of thrombotic events from secondary polycythemia.
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