Don't HIT me one more time: a case report of catheter-directed thrombolysis in a refractory heparin-induced thrombocytopenia-related acute limb ischemia.

Introduction and importance: Heparin-induced thrombocytopenia (HIT) is a severe adverse immune mediated reaction to heparin therapy, particularly relevant in vascular surgery due to its potential life-threatening thrombotic risks. Case presentation and clinical discussion: This report describes a case of refractory HIT following aortobifemoral reconstruction in a 66-year-old patient presenting with peripheral arterial occlusive disease. Initial treatment with argatroban failed to resolve thrombocytopenia, necessitating intravenous immunoglobulin (IVIG). Thrombocytopenia recurred, requiring a second IVIG cycle. Subsequently, the patient developed acute limb ischemia, which was successfully managed with repeated urokinase catheter-directed thrombolysis. Conclusion: This case highlights the challenges of refractory HIT with life-threatening thrombosis, emphasizing the potential role of repeated IVIG treatment and fibrinolytic therapy in this context. Awareness the treatment options for HIT and refractory HIT is crucial for adequate management in vascular surgery.