Medication Summary
Very few studies have addressed the efficacy of any treatment protocol in antiphospholipid antibody syndrome (APS). Most are small retrospective analyses or anecdotal reports. Many prospective studies have included too few patients and have been hampered by a lack of homogeneity of test groups. The Sapporo criteria were established, in part, to ensure a uniform homogeneous test population in order to promote accurate prospective studies of treatment protocols for patients with antiphospholipid antibody syndrome.
Antiplatelet agents
Class Summary
Aspirin inhibits prostaglandin synthesis, preventing formation of platelet-aggregating thromboxane A2. It is used in low doses to inhibit platelet aggregation and improve complications of venous stases and thrombosis. However, doses as low as 5 mg/kg appear to additionally inhibit prostacyclin, thus promoting a procoagulant state. No prevalence data on aspirin resistance in children has been reported. The effect of aspirin on platelet function can be assessed by optical platelet aggregometry or Platelet Function Analyzer (PFA-100). Ticlopidine does not inhibit cyclooxygenase and, in this way, differs from aspirin. It inhibits the primary and secondary phase of aggregation induced by adenosine 5'-diphosphate (ADP) and reduces platelet-derived growth factor. Ticlopidine may also impair platelet adhesion, resulting in prolonged bleeding time. Dipyridamole potentiates the inhibitory effects of aspirin on platelet aggregation.
Aspirin (Anacin, Ascriptin, Bayer Aspirin, Bayer Buffered Aspirin)
Used for antiplatelet effect. Inhibits prostaglandin synthesis, preventing formation of platelet-aggregating thromboxane A2. May be used in low dose to inhibit platelet aggregation and improve complications of venous stases and thrombosis.
Ticlopidine (Ticlid)
Used for livedoid vasculitis and thromboembolic disorders. Second-line antiplatelet therapy for patients who cannot tolerate or in whom aspirin therapy has failed.
Dipyridamole (Persantine)
Used for thromboembolic disorders to complement usual aspirin or warfarin therapy. Platelet adhesion inhibitor that possibly inhibits RBC uptake of adenosine, which is an inhibitor of platelet reactivity. In addition, may inhibit phosphodiesterase activity, leading to increased cyclic-3',5'-adenosine monophosphate within platelets and formation of the potent platelet-activator thromboxane A2.
Used alone or in combination with low-dose aspirin therapy as indicated above. Also used in combination with low-dose PO anticoagulant therapy (with or without aspirin) in children with mechanical prosthetic heart valves.
Anticoagulants
Class Summary
Unfractionated intravenous heparin and fractionated LMW subcutaneous heparin are the choices for initial anticoagulation therapy. If warfarin is chosen as maintenance therapy, it is initiated and concurrently administered with heparin for several days until the international normalized ratio (INR) reaches the target range.
Heparin
Used for thromboembolic disorders. Augments activity of antithrombin III and prevents conversion of fibrinogen to fibrin. Does not actively lyse but is able to inhibit further thrombogenesis. Prevents reaccumulation of clot after spontaneous fibrinolysis. Used as a continuous infusion while initiating PO warfarin therapy.
Enoxaparin (Lovenox)
Used for thromboembolic disorders. Prevents DVT, which may lead to PE in patients undergoing surgery who are at risk for thromboembolic complications.
Enhances inhibition of factor Xa (preferentially) and thrombin (factor IIa) by increasing antithrombin III activity. The ratio of antifactor Xa to antifactor IIa activity is approximately 4:1 (1:1 for unfractionated heparin)
Warfarin (Coumadin)
Used for thromboembolic disorders. Interferes with hepatic synthesis of vitamin K–dependent coagulation factors. Used for prophylaxis and treatment of venous thrombosis, pulmonary embolism, and thromboembolic disorders.
Adjust dose to maintain an INR in the range of 2.5-3.5.
Immunomodulators
Class Summary
Immune globulin is a purified preparation of gamma globulin derived from large pools of human plasma. It is composed of 4 subclasses of IgG antibodies, approximating the distribution of human serum. IgA-depleted products are also low in the IgG4 component.
Immune globulin intravenous (Sandoglobulin, Gammagard, Gamimune, Gammar-P, Gamunex)
Used for autoimmune diseases. Neutralizes circulating myelin antibodies through antiidiotypic antibodies; down-regulates proinflammatory cytokines, including INF-gamma; blocks Fc receptors on macrophages; suppresses inducer T and B cells and augments suppressor T cells; blocks complement cascade; promotes remyelination; may increase CSF IgG (10%).
Vasodilators
Class Summary
These agents are used to lower elevated blood pressure, decrease vasospasm, or prevent ischemia. Niacin is also used to decrease hyperlipidemia.
Nitroglycerin ointment (Nitrol, Nitro-Bid)
Causes relaxation of vascular smooth muscle by stimulating intracellular cyclic guanosine monophosphate production. The result is a decrease in blood pressure.
Onset of action for ointment is 20-60 min. Duration of effect is 2-12 h.
Niacin (Niacor, Niaspan, Nicotinex, Slo-Niacin)
Also called nicotinic acid or vitamin B-3. Component of 2 coenzymes necessary for tissue respiration, lipid metabolism, and glycogenolysis; inhibits synthesis of VLDL. Used as a dietary supplement and as adjunctive treatment of hyperlipidemias, peripheral vascular disease, circulatory disorders, and treatment of pellagra.
Onset of action within 20 min (extended release within 1 h). Duration of effect 20-60 min (extended release 8-10 h). Half-life 45 min.
Drugs with effects on vascular endothelium, platelets, red blood cells
Class Summary
These drugs appear to have multiple mechanisms in the prevention of thrombosis and vascular spasm. The exact mechanisms are largely unexplained, but the properties of these drugs include changes in RBC rheology, inhibition of platelet adhesiveness/activation, inhibition of TNF-alpha production, and decreases in neutrophil and endothelial cell activation.
Pentoxifylline (Trental)
Used in vascular disease. May alter rheology of RBCs, which, in turn, reduces blood viscosity. Improves peripheral perfusion and vascular spasm in Raynaud phenomenon and vasculopathy/vasculitis.
Other effects include inhibition of platelet adhesiveness/activation, inhibition of TNF-alpha production, and decrease in neutrophil and endothelial cell activation.
Hydroxychloroquine (Plaquenil)
Inhibits platelets, chemotaxis of eosinophils, and locomotion of neutrophils and impairs complement-dependent antigen-antibody reactions.
Hydroxychloroquine sulfate 200 mg is equivalent to 155 mg hydroxychloroquine base and 250 mg chloroquine phosphate.
Cilostazol (Pletal)
Affects vascular beds and cardiovascular function. May improve blood flow by altering rheology of RBCs. Produces nonhomogenous dilation of vascular beds, with more dilation in femoral beds than in vertebral, carotid, or superior mesenteric arteries.
Cilostazol and its metabolites are inhibitors of phosphodiesterase III and, as a result, cyclic AMP is increased, which leads to inhibition of platelet aggregation and vasodilation.
Platelet count enhancers
Class Summary
These agents are used to augment platelet recovery.
Vincristine (Oncovin, Vincasar PFS)
Mechanism of action for treatment of thrombocytopenia is uncertain. May involve a decrease in reticuloendothelial cell function or an increase in platelet production. However, neither of these mechanisms fully explains the effect in TTP and HUS.
Danazol (Danocrine)
Synthetic steroid analog with strong antigonadotropic activity (inhibits LH and FSH) and weak androgenic action.
Increases levels of C4 component of complement and reduces attacks associated with angioedema. In hereditary angioedema, danazol increases level of deficient C1 esterase inhibitor.
Other therapy with multiple actions
Class Summary
Medications with vasodilatory and antiplatelet activity with specific usage in the treatment of pulmonary hypertension and/or healing of refractory skin ulcerations have been administered in patients with APS. [91, 92, 93]
Bosentan (Tracleer)
Endothelin-receptor antagonist indicated for the treatment of pulmonary arterial hypertension in patients with WHO class III or class IV symptoms to improve exercise ability and decrease rate of clinical worsening. Inhibits vessel constriction and elevation of blood pressure by competitively binding to the endothelin-1 (ET-1) receptors ETA and ETB in endothelium and vascular smooth muscle. This leads to a significant increase in the cardiac index (CI) associated with significant reduction in pulmonary artery pressure (PAP), pulmonary vascular resistance (PVR), and mean right atrial pressure (RAP). Due to teratogenic potential, can only be prescribed through the Tracleer Access Program (1-866-228-3546).
Epoprostenol (Flolan)
Prostacyclin, PGI2 analogue that has potent vasodilatory properties. Elicits immediate onset of action. Half-life is approximately 5 min. In addition to vasodilator properties (all vascular beds), also contributes to inhibition of platelet aggregation (activates intracellular adenylate cyclase and results in increased CAMP in platelets) and plays role in inhibition of smooth muscle proliferation.
Sildenafil (Viagra, Revatio)
FDA-approved for pulmonary hypertension. Promotes selective smooth muscle relaxation in lung vasculature possibly by inhibiting phosphodiesterase type 5 (PDE5). This results in subsequent reduction of blood pressure in pulmonary arteries and increase in cardiac output. Elicits vasodilation and inhibits platelet aggregation. Also aids in healing refractory skin ulcerations.
Antilipemic Agent
Class Summary
Therapy for dyslipoproteinemia or hyperlipidemia may reduce vascular risk factors for thrombosis. In vitro and animal model evidence suggests decreased endothelial cell and granulocyte activation. [100, 96]
Atorvastatin (Lipitor)
The most efficacious of the statins at high doses. Inhibits 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA reductase), which in turn inhibits cholesterol synthesis and increases cholesterol metabolism. Reports have shown as much as a 60% reduction in LDL-C. The Atorvastatin versus Revascularization Treatment study (AVERT) compared 80 mg atorvastatin daily to standard therapy and angioplasty in patients with CHD. While events at 18 mo were the same between both groups, the length of time until the first CHD event occurred was longer with aggressive LDL-C lowering. The half-life of atorvastatin and its active metabolites is longer than that of all the other statins (ie, approximately 48 h compared to 3-4 h).
May modestly elevate HDL-C levels. Clinically, reduced levels of circulating total cholesterol, LDL-C, and serum TGs are observed.
Before initiating therapy, patients should be placed on a cholesterol-lowering diet for 3-6 mo; the diet should be continued indefinitely.
Pravastatin (Pravachol)
Effective in reducing circulating lipid levels and improving the clinical and anatomic course of atherosclerosis.
Simvastatin (Zocor)
Inhibits cholesterol synthesis and increases cholesterol metabolism.
Biological response modulator
Class Summary
Targeted anti-B cell therapy has been used in the treatment of refractory idiopathic thrombocytopenic purpura (ITP) postsplenectomy. The use of this modality has been extrapolated to treatment protocols for antiphospholipid syndrome. [101, 102, 103]
Rituximab (Rituxan)
Indicated to reduce signs and symptoms for moderately-to-severely active rheumatoid arthritis in combination with methotrexate. For use in adults who have experienced an inadequate response to one or more TNF antagonist therapies. Antibody genetically engineered. Chimeric murine/human monoclonal antibody directed against the CD20 antigen found on surface of B-lymphocytes.
-
Palmar livedo reticularis associated with antiphospholipid antibody syndrome may range from a lacy, flat, reticulated pattern to a more confluent, nonblanching, slightly raised rash (secondary to extravasation of RBCs and plasma).
-
Livedo reticularis of the upper and lower extremities in a 15-year-old adolescent with primary antiphospholipid antibody syndrome. The pattern is lacy, flat, and nonblanching. The purplish hue is from stasis in the small vessel beds.
-
Muddy discoloration and mild diffuse swelling of the fingers observed as part of the Raynaud phenomenon, which is associated with antiphospholipid antibody syndrome. At room temperature, this patient still has decreased capillary refill and cold fingers despite treatment with pentoxifylline. The discoloration extends proximally onto the palms and turns blue-purple when exposed to cold.
-
Linear splinter hemorrhages are found under the nails of fingers and toes. These may be solitary or multiple and appear intermittently.
-
One set of suggested algorithms for the workup and treatment of patients with antiphospholipid antibody syndrome. This should not be considered dogmatic because laboratory evaluation is not standardized and treatment remains empiric and controversial. Laboratory testing is not recommended in healthy asymptomatic individuals with no risk factors and a negative family history.
-
Occlusion of the right middle cerebral artery in a 3-year-old child with severe headache and hemiparesis associated with anticardiolipin antibodies.
-
Organizing thrombus in an aortic valve in a patient with positive test results for antiphospholipid antibody and lupus anticoagulant who has systemic lupus erythematosus (SLE) and recurrent thrombotic events. The authors acknowledge the help of Hannes Vogel, MD, in preparing this image.
-
High-power degenerating aortic valve in a patient who has positive test results for antiphospholipid antibody and lupus anticoagulant and who has systemic lupus erythematosus (SLE) and recurrent thrombotic events. The authors acknowledge the help of Hannes Vogel, MD, in preparing this image.
-
Trichrome stain of a thrombus in the intestinal serosa in a patient who has positive test results for antiphospholipid antibody and lupus anticoagulant and who has systemic lupus erythematosus (SLE) and catastrophic antiphospholipid antibody syndrome (CAPS). The authors acknowledge the help of Hannes Vogel, MD, in preparing this image.
-
Antiphospholipid antibody syndrome in a patient with positive test results for antiphospholipid antibody and lupus anticoagulant who has systemic lupus erythematosus (SLE), World Health Organization (WHO) class IV lupus nephritis, and acute renal failure. Top: Thrombosed kidney vessels (periodic acid-Schiff [PAS], original magnification X40). Bottom: Thrombosed kidney vessels (PAS, original magnification X20). Lumen is filled with eosinophilic fibrin with overlying injured endothelial cells. The authors acknowledge the help of Karen W. Eldin, MD, in preparing this image.
-
Antiphospholipid antibody syndrome in a patient with positive test results for antiphospholipid antibody and lupus anticoagulant who has systemic lupus erythematosus (SLE), World Health Organization (WHO) class IV lupus nephritis, and acute renal failure. Top: Thrombosed kidney vessel (hematoxylin and eosin [H&E] stain, original magnification X20). Lumen is occluded with fibrin. A perivascular stromal reaction with degenerating inflammatory cells is observed. Bottom: Thrombosed kidney vessel (H&E stain, original magnification X20). Lumen is occluded with fibrin. The authors acknowledge the help of Karen W. Eldin, MD, in preparing this image.
-
Antiphospholipid antibody syndrome in a patient with positive test results for antiphospholipid antibody and lupus anticoagulant who has systemic lupus erythematosus (SLE), World Health Organization (WHO) class IV lupus nephritis, and acute renal failure. Thrombosed kidney vessel with recanalization (arrows) (Jones stain, original magnification X20). Architectural distortion in the surrounding stroma is observed. The authors acknowledge the help of Karen W. Eldin, MD, in preparing this image.
-
Antiphospholipid antibody syndrome in a patient with positive test results for antiphospholipid antibody and lupus anticoagulant who has systemic lupus erythematosus (SLE) and thrombocytopenia. Livedo reticularis of the upper extremities, which developed as petechiae in the classic lacy, reticular pattern, is observed.
-
Livedo reticularis of the upper extremities, which developed as petechiae in the classic lacy, reticular pattern and evolved as a confluent, nonblanching, slightly raised purpuric rash in the same reticular pattern.
-
Digital infarctions in a patient with systemic lupus erythematosus with antiphospholipid syndrome (APS) and long-standing Raynaud symptoms. Multiple and repeated digital infarctions are depicted, resulting in ulcerations and scarring. Scars and hyperpigmentation are also seen on the palmer aspect of hands and fingers.
-
A patient with multisystem small vessel coagulopathy (microangiopathy) but no known underlying disease process. Extensive involvement of all digits is noted, some with distal infarction and dry gangrene, others healing with residual eschar (and undermining epithelialization), and some with re-epithelialization and scarring. Healed superficial epidermal damage and desquamation is also present.
-
A patient with multisystem small vessel coagulopathy (microangiopathy) but no known underlying disease process. Eschar is still present on first digit bilaterally. More superficial lesions are shown here, with evolution and healing of lesions on all other toes.
-
CAPS, Bone Infarction - MRI (High Resolution Proton Density and STIR images) and Nuclear Bone Scan - Patient with multisystem small vessel coagulopathy (microangiopathy) but no known underlying disease process. MRI shows multiple infarctions in the distal tibia, tarsal bones and metatarsal bones (extensive bone marrow edema and increased T1 with fat saturation signal in the calcaneus bones). Flow and early blood pool images of technetium 99m bone scan show increase in activity in both heel regions with focal areas of decreased activity in the center of each calcaneus.
-
A patient with multisystem small vessel coagulopathy (microangiopathy) but no known underlying disease process. The technetium 99m bone scan reveals irregular multifocal areas of tracer accumulation within the left ventricle of the heart suggestive of myocardial infarction and altered calcium deposition. Irregular cutaneous and subcutaneous uptake is noted in multiple areas of the torso and upper arms (as well as in the upper thighs). High-resolution CT scanning of the chest reveals extensive calcification involving the myocardium, the mitral and tricuspid valve annuli, the aortic valve annulus, the proximal right coronary artery, and the left main coronary artery.
