Successful outcome with eculizumab treatment in a patient with antiphospholipid syndrome presenting with an unusual thrombotic storm.

Catastrophic Antiphospholipid Syndrome (CAPS) is a life-threatening complication of APS requiring complex management to optimize patient outcome. We describe a 54-year-old man with APS with history of splanchnic vein thrombosis, a Factor II G20210A heterozygote, autoimmune hemolytic anemia and thrombocytopenia. He developed sudden onset of severe flank pain due to spontaneous bilateral adrenal hemorrhage while on warfarin with a therapeutic INR. Despite unfractionated heparin and initial clinical improvement, severe thrombocytopenia developed requiring dexamethasone, rituximab, and romiplostim. Hospitalization was complicated further by thrombosis of the inferior vena cava, pulmonary embolism, and painful violaceous patches on his neck and ear cartilages. Punch biopsy of lesions revealed C5b-C9 deposition of small vessel thromboses. Although the inciting event for his thrombotic storm remains uncertain, anti-complement therapy with eculizumab provided rapid and durable lesion resolution. Eculizumab was discontinued after 6 months and patient remains in remission without recurrent thrombosis. This case provides insight on the management of CAPS, including the use of eculizumab.