Phlegmasia caerulea dolens secondary to pelvic plasmacytoma and left femoral deep vein thrombosis.

Introduction: Phlegmasia caerulea dolens (PCD) is a clinical syndrome caused by venous obstruction leading to peripheral limb ischaemia. It can ultimately lead to venous gangrene, amputation or death in 25% of cases.

Presentation Of Case: A 52-year-old man with a background of myeloma developed PCD secondary to an obstructing plasmacytoma and left femoral vein deep vein thrombosis (DVT). These were treated with combined radiotherapy and anticoagulation, with resolution of the patient's symptoms. His recovery was complicated by the development of heparin-induced thrombocytopenia (HIT) and cutaneous vasculitis.

Discussion: Both plasmacytoma and DVT are recognised complications of myeloma. This is, to our knowledge, the first description of these phenomena in combination causing PCD. The combination of venous stasis from the obstructing plasmacytoma and hypercoagulability from the underlying myeloma may have contributed to clot formation. A multifaceted treatment approach was required which aimed at improving venous flow via radiotherapy to the plasmacytoma and dissolving the obstructing clot with anticoagulant therapy.

Conclusion: PCD has a high mortality and morbidity. Recognition is important to avoid an incorrect diagnosis of arterial occlusion and inappropriate surgical intervention. Treatment must be focused on removing the offending causes.