Controversies and unresolved issues in antiphospholipid syndrome pathogenesis and management

Recurrent thrombosis in patients with antiphospholipid antibodies and arterial thrombosis on antithrombotic therapy

Management for patients with antiphospholipid syndrome (APS) and arterial thrombosis is controversial. There are no prospective data demonstrating the superiority of high- or moderate-intensity anticoagulation with vitamin K antagonists over antiplatelet agents. Using 2 antiphospholipid antibody databases (single center [New York Presbyterian Hospital] and multicenter [Antiphospholipid Syndrome Alliance for Clinical Trials and International Networking]), we retrospectively collected demographic and clinical data of patients with APS and arterial thrombosis. The primary outcome was recurrent thrombosis rate after initial arterial thrombosis in patients with APS treated with antiplatelet and/or anticoagulant therapy. We identified 139 patients with a median follow-up time of 4.24 years after initial thrombosis. Thirty-seven patients (27.3%) received anticoagulants, 43 (30.9%) antiplatelets, and 58 (41.7%) combined therapy. Sixteen patients (37.2%) in the antiplatelet group, 9 (23.7%) in the anticoagulant group, and 4 (6.9%) in the combined therapy group experienced recurrent thrombosis. We estimate that 20% of patients will experience a recurrence by 3.4, 7.3, and 16.3 years, respectively, depending on assignment to antiplatelet, anticoagulant, or combined therapy. These results suggest that combined therapy decreases the rate of and increases the time to thrombosis recurrence in patients with APS presenting with arterial thrombosis.

Multiple recurrent stent thrombosis in a patient with coexisting clopidogrel resistance and increased anticardiolipin antibodies: a case report

The antiphospholipid syndrome (APS) is a common cause of both arterial and venous thrombosis. While studies exist demonstrating the role of APS in coronary artery bypass graft failure, its role in stent thrombosis is less clearly documented. Also, a literature search of PubMed did not reveal any articles regarding the coexistence of clopidogrel resistance and APS despite increasing awareness of resistance to clopidogrel treatment. We present a case of a 59-year-old male having recurrent myocardial infarction after subacute restenosis of multiple drug-eluting stents despite anticoagulant therapy. The patient had in-stent thrombosis of seven drug-eluting stents in a course of eight days. He was subsequently found to have mild elevation of IgG anticardiolipin (aCL) antibody titers and resistance to clopidogrel. Long-term anticoagulation with a combination of low-molecular-weight heparin, clopidogrel, and aspirin has been effective. While the patient's aCL titer level was not elevated above the level required by the current diagnostic criteria for APS, we believe that this patient suffers from the antiphospholipid syndrome. We will discuss some of the controversies surrounding the diagnosis of APS as well as appropriate treatment and recognition of the coexistence of APS and clopidogrel resistance in patients with stent thrombosis.

Catastrophic antiphospholipid syndrome in a child with trisomy 21. An acquired thrombopathy with a discussion of thrombopathies in childhood

Antiphospholipid syndrome (APLS), an acquired thrombophilic disorder involving autoantibodies against phospholipids and phospholipid-binding proteins, is often accompanied by autoimmune disease but also occurs in the absence of any documented autoimmune disease. It is known to be more common in individuals with trisomy 21. Catastrophic APLS (CAPLS), a rare accelerated form of APLS, leads to acute multisystem organ failure, with microthrombi in multiple organs and a mortality rate of 50% or greater. The youngest case of APLS was reported in a 7-year-old child. We report the pathologic findings in a case of CAPLS in a 2-year-old girl with trisomy 21 who presented with an insidious skin rash, which was rapidly followed by multiorgan failure and death. All major criteria for the diagnosis of CAPLS were met, including the involvement of 3 or more organ systems, precipitous clinical deterioration, positive serology for APL, and noninflammatory microthrombi in at least one organ which, in this case, included multiple sites: skin, lungs, intestinal tract with necrotizing enterocolitis, and spleen, with multiple infarcts all documented at autopsy.

Antiphospholipid syndrome

The antiphospholipid syndrome (APS) is an autoimmune systemic disease that is diagnosed when there is vascular thrombosis and/or pregnancy morbidity occurring with persistently positive antiphospholipid antibodies (aPL) (lupus anticoagulant test, anticardiolipin antibodies, and/or anti-beta(2)-glycoprotein I antibodies). Although International APS Classification Criteria have been formulated to provide a uniform approach to APS research, aPL may cause a spectrum of clinical manifestations, some of which are not included in these criteria. The main aPL-related cardiac manifestations include valve abnormalities (vegetations and/or thickening), myocardial infarction (MI), intracardiac thrombi, and myocardial microthrombosis. In this article, we will review the definition, etiopathogenesis, clinical manifestations, diagnosis, and treatment of aPL-related clinical events with emphasis on cardiac manifestations.

Recent Publications on Medications and Pharmacy

Hospital Pharmacy presents this feature to keep pharmacists abreast of new publications in the medical/pharmacy literature. Articles of interest will be abstracted monthly regarding a broad scope of topics. Suggestions or comments may be addressed to: Jacyntha Sterling, Drug Information Specialist at Saint Francis Hospital, 6161 S Yale Ave., Tulsa, OK 74136 or e-mail: jasterling@saintfrancis.com .