RT Journal Article SR Electronic T1 Treatment of catastrophic antiphospholipid syndrome with defibrotide, a proposed vascular endothelial cell modulator. JF The Journal of Rheumatology JO J Rheumatol FD The Journal of Rheumatology SP 2006 OP 2011 VO 29 IS 9 A1 Burcoglu-O'Ral, Arsinur A1 Erkan, Doruk A1 Asherson, Ronald YR 2002 UL http://www.jrheum.org/content/29/9/2006.abstract AB OBJECTIVE: To define at the molecular level the vascular endothelial cell (VEC) injury characteristics of catastrophic antiphospholipid syndrome (CAPS) and to report successful therapeutic use of a VEC modulator, defibrotide. METHODS: We describe a 55-year-old man with primary APS with an intractable prothrombotic state (CAPS) resistant to combined therapy with heparin, warfarin, aspirin, and dipyridamole. Treatment with defibrotide was conducted in the context of an investigational phase II protocol where the dose was regulated and individualized by disease/patient-specific molecular and clinical markers. RESULTS: The patient entered complete remission with defibrotide treatment. During treatment, dose dependent pharmacological actions of defibrotide and key stress markers for VEC injury were identified. Evidence of defibrotide's polypharmacology included downregulation of cytokines, notably tumor necrosis factor-alpha, as the earliest effect, cellular differentiation of VEC, possibly with direct regulatory effect over cellular genes, and the reversal of platelet consumption and prothrombotic state. Von Willebrand antigen levels were used as the sole marker to guide therapy. CONCLUSION: This case demonstrates effective remission of CAPS with defibrotide treatment. In contrast to theories that CAPS is triggered by ischemic and thrombotic tissue damage, these data present VEC injury as the primary and representative lesion of CAPS. The pathogenesis may involve concurrent impairment of different VEC functions. Achieving remission may require a polypharmacologic approach, represented here by use of defibrotide.