Abstract
Takayasu arteritis (TA) is a rare, immune-mediated large-vessel vasculitis that primarily affects the aorta and its major branches. While several infectious agents have been implicated as potential environmental triggers, necrotizing fasciitis (NF) has not been previously linked to the onset of TA. We report the case of a previously healthy 33-year-old woman who developed rapidly progressive TA following NF of the left lower limb. Despite broad-spectrum antibiotics and surgical debridement, the patient exhibited persistent fever, leukocytosis, and new-onset hypertension. Imaging revealed new inflammatory changes in the thoracic and abdominal aorta, consistent with large-vessel vasculitis. A diagnosis of TA was established based on the findings of magnetic resonance angiography. Following high-dose corticosteroid therapy, the patient showed rapid clinical improvement. Cyclophosphamide was initiated, and follow-up imaging confirmed partial resolution of vascular inflammation. This case highlights NF as a potential immunologic trigger for TA. In patients with persistent systemic inflammation despite adequate infection control, autoimmune vasculitis should be considered as a possible underlying cause. Early diagnosis and prompt immunosuppressive therapy can lead to significant clinical improvement.