Subclavian Steal Syndrome as the Initial Presentation of Takayasu's Vasculitis in a Young Caucasian Female.

Takayasu arteritis (TAK) is a rare but well-known inflammatory disease affecting large vessels that leads to thickening, narrowing, occlusion, or dilation of the affected arteries. The overall effect of the disease is arterial insufficiency of the brain and/or the distal part of the affected vessel. Subclavian steal syndrome has been observed as a form of presentation where there is occlusion of the proximal subclavian artery that results in a reversal of flow in the ipsilateral vertebral artery, consequently diverting or 'stealing' blood from the contralateral vertebral artery. Our patient is a 34-year-old Caucasian female presenting with subclavian steal syndrome as the initial presentation of TAK. She presented to the emergency department following a syncopal episode and six months prior history of intermittent lightheadedness, vertigo, left upper extremity pain, numbness, and tingling which was said to be aggravated with activity and alleviated with rest. Examination findings revealed non-palpable left brachial and radial pulses of the upper limb with an inaudible blood pressure reading on the ipsilateral side and blood pressure of 113/70 mmHg on the contralateral arm. Investigation revealed elevated acute phase reactant, normocytic anemia, and inflammation of the aorta on imaging. She was evaluated by the vascular surgery team who recommended medical management. The patient was managed with steroids and methotrexate, and her symptoms improved significantly with the normalization of laboratory findings. She is currently being followed up by the vascular surgery and rheumatology teams. We emphasize the importance of understanding the varied clinical spectrum of TAK and the need to have a high index of suspicion for TAK in a young female with recurrent syncope and unilateral upper extremity intermittent numbness and paresthesia.