RESUMO
Dorsalis pedis artery (DPA) aneurysms are very rare and fewer than 60 cases have been reported in the literature. Most affected patients present with false aneurysms after orthopedic surgery or trauma. Here we report an unusual case of a giant DPA pseudoaneurysm after cannulation for arterial line placement in a patient newly diagnosed with systemic lupus erythematosus (SLE). A diagnostic delay resulted in necrosis of the overlying skin. Excision of the pseudoaneurysm, ligation of the DPA, and debridement of the foot dorsum were performed, followed by a second flap coverage surgery. Although a DPA false aneurysm is rare after arterial line removal, it can cause the serious complications of skin necrosis, rupture and toe necrosis. Arterial puncture sites should be carefully monitored, especially in patients with SLE or other vasculitis.