Phlegmasia Cerulea Dolens Secondary to Iliac Vein Compression From Posttransplant Hematoma Despite Anticoagulation

Background: Phlegmasia cerulea dolens is a rare, life- and limb-threatening form of venous thrombosis that is often seen in the setting of hypercoagulable states or mechanical obstruction. Case Report: We report the case of a 49-year-old female with a history of multiple thromboembolic events and a methylenetetrahydrofolate reductase mutation who, despite therapeutic anticoagulation, developed phlegmasia cerulea dolens following renal transplantation. Her postoperative course was marked by recurrent hemorrhage with rapidly reaccumulating subincision and perinephric hematomas, requiring 4 exploratory laparotomies for hematoma evacuation and graft evaluation. In addition, the patient underwent urgent endovascular suction thrombectomy for extensive iliofemoral thrombosis caused by extrinsic iliac vein compression. Conclusion: This case highlights the complex interplay between bleeding and clotting in high-risk transplant recipients and the need for nuanced anticoagulation management. Although phlegmasia cerulea dolens is rare, clinicians must keep a high index of suspicion for the pathology, as early recognition and timely intervention can be both life- and limb-saving.