Lessons of the month 2: Retinal vasculitis: a first presentation of Takayasu's arteritis.

Takayasu's arteritis is a chronic, systemic, large-vessel vasculitis affecting the aorta and its primary branches. However, coronary, renal and pulmonary arteries and small vessel involvement has been documented. We describe a rare case of Takayasu's arteritis with extensive supra-aortic arch disease, manifesting with bilateral occlusive retinal vasculitis as a first presentation. This is elicited by fundus findings of vascular sheathing and fundus fluoresceine angiography evidence of retinal vessel occlusion and peripheral capillary non-perfusion. © Royal College of Physicians 2021. All rights reserved.