Atypical Posterior Reversible Encephalopathy Syndrome as the Sentinel Presentation of Takayasu’s Arteritis

Posterior reversible encephalopathy syndrome (PRES) is a neurological disorder marked by headache, convulsive episodes, visual deficits, and altered sensorium. PRES is accompanied by reversible vasogenic edema that predominantly affects the posterior cerebral hemispheres. It is often precipitated by acute hypertension, renal dysfunction, or autoimmune diseases. Takayasu arteritis (TA) is a chronic granulomatous vasculitis of the large vessels, characterized by progressive inflammation of the aorta and its primary arterial segments. PRES may rarely present as a life-threatening neurological complication of TA. This case describes an 18-year-old male who had atypical PRES, driven by a hypertensive emergency, likely linked to renal artery stenosis caused by the patient’s chronic unrecognized vasculitis. Through this case, we wish to emphasize that neurological symptoms of PRES can be the sentinel event leading to an initial diagnosis of Takayasu’s arteritis.