SAT-578 Auto-amputation Of The Great Toe In A Female Patient With Type 2 Diabetes And Protein S Deficiency: A Case Report

Abstract Disclosure: U. Dey: None. Background: Foot complications in type 2 diabetes mellitus (T2DM) are common, often linked to peripheral neuropathy and macrovascular disease. However, inherited thrombophilias, such as Protein S deficiency, are rarely considered contributors to limb ischemia. We report a rare case of spontaneous auto-amputation of the great toe in a patient with T2DM and Protein S deficiency, highlighting the importance of evaluating non-traditional causes of vascular events. Case Presentation: A 47-year-old South Asian female with poorly controlled T2DM presented with spontaneous detachment of her left great toe following several months of progressive black discoloration and numbness. She had no history of trauma or infection. On examination, dry gangrene of the great toe and absent posterior tibial pulses were noted. The diagnosis of acute on chronic ischemia of the left lower limb was confirmed via Doppler ultrasound, which revealed occlusion in the posterior tibial and dorsalis pedis arteries.Emergency thromboembolectomy of the left popliteal artery, anterior tibial artery, and posterior tibial trunk was performed. Postoperatively, the posterior tibial artery pulse remained feeble, though all other pulses normalized. Laboratory evaluation showed markedly reduced free Protein S activity (37.6%; normal >50%) with normal Protein C and antithrombin III levels. No autoimmune or infectious etiology was found. A hematology consult confirmed inherited heterozygous Protein S deficiency. Management and Outcome: The patient was started on rivaroxaban and optimized glycemic control. The gangrenous toe separated spontaneously, and the wound healed with conservative management. She remained stable over a six-month follow-up without further ischemic episodes. Conclusion: This case emphasizes the importance of screening for thrombophilic disorders in diabetic patients with atypical or unexplained ischemic events. Protein S deficiency, though rare, can lead to severe vascular complications, including spontaneous auto-amputation. Multidisciplinary care and early anticoagulation are essential in improving outcomes in such complex presentations. Presentation: Saturday, July 12, 2025