Pediatric Antiphospholipid Antibody Syndrome Clinical Presentation
- Author: Barry L Myones, MD; Chief Editor: Lawrence K Jung, MD more...
History
Vasospastic or vaso-occlusive events can occur in any organ system in patients with antiphospholipid antibody (aPL) syndrome (APS); thus, a thorough history should be taken, and an organ-specific review of systems should be performed. A broad spectrum of involvement ranging from rapidly progressive to clinically silent and indolent may be present.[2, 3, 4, 5, 6, 11]
- Head, ears, eyes, nose, and throat
- Blurred or double vision
- Visual disturbance ("wavy lines,” “flashing lights")
- Visual loss (field cuts, total vision loss)
- Cardiorespiratory
- Chest pain
- Radiating arm pain
- Shortness of breath
- Gastrointestinal
- Abdominal pain
- Abdominal distension (bloating)
- "Abdominal migraine"
- Emesis
- Peripheral vascular
- Leg pain
- Leg swelling
- Claudication
- Digital ulcerations
- Leg ulcerations
- Cold-induced finger pain, toe pain, or both
- Musculoskeletal
- Bone pain
- Joint pain
- Cutaneous
- Purpuric rashes, petechial rashes, or both
- Persistent or transient lacy rashes of livedo reticularis
- Dusky fingers, dusky toes, or both
- Blanching of fingers, blanching of toes, or both
- Neurologic and psychiatric
- Syncope
- Seizures
- Headache (migraine)
- Paresthesias
- Paralysis
- Ascending weakness
- Tremors
- Abnormal movements
- Memory loss
- Problems with concentrating, reading comprehension, calculations (change in school performance)
- Endocrine - Weakness, fatigue, arthralgia, abdominal pain (Addisonian features)
- Genitourinary/renal
- Hematuria
- Peripheral edema
- Pregnancy-related history - Not expected to be of frequent concern in the field of pediatrics but may be significant in teenagers
- Family history
- A strong family history is more pertinent to most pediatric patients and may assist in identifying patients at risk.
- Family history may include the following:
- Frequent miscarriage, premature birth, intrauterine growth retardation (IUGR), oligohydramnios, chorea gravidarum, placental infarction, preeclampsia, toxemia of pregnancy, or neonatal thromboembolism
- Myocardial infarction or stroke in persons younger than 50 years
- Deep vein thrombosis (DVT), phlebitis, or pulmonary embolus
- Strong family history of migraine, Raynaud phenomenon, or transient ischemic attacks (TIAs)
- Medication history - Use of oral contraceptives at the time of a clinical event
Physical
Physical findings are specific to the affected organ and can involve any organ system.[36] Catastrophic antiphospholipid antibody syndrome (CAPS) is a multisystem failure secondary to thrombosis, infarction, or both and has a picture of microangiopathy on histology.[37, 38, 39, 40, 18, 41]
- Peripheral vascular
- Point tenderness to palpation of bone or joints (bone infarction), as shown below
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. - Pain on range of motion of joints without arthritis (avascular necrosis)
- Limb swelling (DVT)
- Peripheral edema (DVT, renal vein thrombosis)
- Decreased capillary refill (arterial thrombosis, vasospasm)
- Decreased pulses (arterial thrombosis, vasospasm)
- Decreased perfusion (arterial thrombosis, vasospasm)
- Gangrene (arterial thrombosis, infarction), as shown below
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.
- Point tenderness to palpation of bone or joints (bone infarction), as shown below
- Pulmonary - Respiratory distress, tachypnea (pulmonary embolism [PE], pulmonary hypertension)[42]
- Renal[43, 44, 45, 46, 47, 48]
- Hypertension (renal artery thrombosis, intrarenal vascular lesions)
- Hematuria (renal vein thrombosis)
- Acute renal insufficiency (intrarenal vascular lesions), as shown below
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.
- Cardiac[49, 50, 51, 52, 53, 54]
- Insufficiency murmur of aortic, mitral valve (endocarditis)
- Chest pain, diaphoresis (myocardial infarction)
- GI
- Right upper quadrant tenderness, hepatomegaly (Budd-Chiari syndrome,[55] hepatic small vessel thrombosis, hepatic infarction)
- Abdominal tenderness (mesenteric artery thrombosis)
- Endocrine - Muscle weakness, progressive stiffening of pelvic and thigh muscles with flexion contractures associated with adrenal insufficiency (adrenal infarction/hemorrhage)[56]
- Ocular
- Retinal artery occlusion
- Retinal vein thrombosis
- Skin manifestations
- Livedo reticularis, shown below
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. - Purpuric lesions, as shown below
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. - Superficial thrombophlebitis
- Vasospasm (ie, Raynaud phenomenon), as shown below
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. - Splinter hemorrhages (periungual, subungual), as shown below
Linear splinter hemorrhages are found under the nails of fingers and toes. These may be solitary or multiple and appear intermittently. - Peripheral infarctions (digital pitting), as below
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. - Skin ulcerations (eg, leg ulcers)
- Petechiae (associated with thrombocytopenia), as shown below
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. - Bruising (associated with thrombocytopenia)
- Livedo reticularis, shown below
- Central or peripheral nervous system abnormalities[57, 58, 59, 60]
- Stroke, cerebrovascular accident (CVA)
- TIA
- Paresthesia, polyneuritis, or mononeuritis multiplex (vasovasorum ischemia/infarction)
- Paralysis, hyperreflexia, weakness (transverse myelitis, Guillain-Barré syndrome)
- Movement disorders - Choreiform tremors (cerebral, cerebellar, basal ganglia infarction)
- Multiple sclerosis–like disorder
- Learning disability
- Short-term memory loss
Causes
The causes of antiphospholipid antibody syndrome are unknown (see Pathophysiology).
The association of thrombotic events with preexisting or coincident vascular perturbation is emphasized by the high incidence of antiphospholipid antibody syndrome in patients with the following conditions:
- Vascular inflammation, vasculitis
- Autoimmune disease (eg, systemic lupus erythematosus [SLE], cryoglobulinemia)
- Infectious processes (eg, hepatitis, parvovirus, syphilis)
- Malignancy (eg, carcinoma, leukemia)
- Vascular trauma
- Postsurgery (eg, cardiac)
- Trauma (eg, accidental)
- Drug-induced state (eg, procainamide, phenytoin, hydralazine, chlorpromazine)
- Hemodialysis-associated condition (increased antiphospholipid antibody antibodies over time on dialysis)
- Cuprophane membrane exposure
- Oxidative stress
Myones BL, McCurdy D. The antiphospholipid syndrome: immunologic and clinical aspects. Clinical spectrum and treatment. J Rheumatol. Apr 2000;27 Suppl 58:20-8. [Medline].
Cuadrado MJ, Hughes GR. Hughes (antiphospholipid) syndrome. Clinical features. Rheum Dis Clin North Am. Aug 2001;27(3):507-24, v. [Medline].
Roubey RA. Antiphospholipid antibody syndrome. In: Koopman's Textbook of Arthritis and Allied Health Conditions. 14th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2001:1546-61.
Levine JS, Branch DW, Rauch J. The antiphospholipid syndrome. N Engl J Med. Mar 7 2002;346(10):752-63. [Medline].
Lockshin MD. Antiphospholipid antibody syndrome. Rheum Dis Clin North Am. Feb 1994;20(1):45-59. [Medline].
Cimaz R, Descloux E. Pediatric antiphospholipid syndrome. Rheum Dis Clin North Am. Aug 2006;32(3):553-73. [Medline].
Petri M. Epidemiology of the antiphospholipid antibody syndrome. J Autoimmun. Sep 2000;15(2):145-51. [Medline].
Welsch S, Branch DW. Antiphospholipid syndrome in pregnancy. Obstetric concerns and treatment. Rheum Dis Clin North Am. Feb 1997;23(1):71-84. [Medline].
Hansen KE, Kong DF, Moore KD, Ortel TL. Risk factors associated with thrombosis in patients with antiphospholipid antibodies. J Rheumatol. Sep 2001;28(9):2018-24. [Medline].
Harris EN, Pierangeli SS. 'Equivocal' antiphospholipid syndrome. J Autoimmun. Sep 2000;15(2):81-5. [Medline].
Avcin T, Cimaz R, Silverman ED, et al. Pediatric antiphospholipid syndrome: clinical and immunologic features of 121 patients in an international registry. Pediatrics. Nov 2008;122(5):e1100-7. [Medline].
Amigo MC, Khamashta MA. Antiphospholipid (Hughes) syndrome in systemic lupus erythematosus. Rheum Dis Clin North Am. May 2000;26(2):331-48. [Medline].
Wilson WA, Gharavi AE, Koike T, et al. International consensus statement on preliminary classification criteria for definite antiphospholipid syndrome: report of an international workshop. Arthritis Rheum. Jul 1999;42(7):1309-11. [Medline].
Wilson WA, Gharavi AE, Piette JC. International classification criteria for antiphospholipid syndrome: synopsis of a post-conference workshop held at the Ninth International (Tours) aPL Symposium. Lupus. 2001;10(7):457-60. [Medline].
Lockshin MD, Sammaritano LR, Schwartzman S. Validation of the Sapporo criteria for antiphospholipid syndrome. Arthritis Rheum. Feb 2000;43(2):440-3. [Medline].
Wilson WA. Classification criteria for antiphospholipid syndrome. Rheum Dis Clin North Am. Aug 2001;27(3):499-505, v. [Medline].
Miyakis S, Lockshin MD, Atsumi T. International consensus statement on an update of the classification criteria for definite antiphospholipid syndrome (APS). J Thromb Haemost. Feb 2006;4(2):295-306. [Medline].
[Guideline] Asherson RA, Cervera R, de Groot PG, et al. Catastrophic antiphospholipid syndrome: international consensus statement on classification criteria and treatment guidelines. Lupus. 2003;12(7):530-4. [Medline].
Giordano P, Tesse R, Lassandro G, Fracchiolla D, Ranieri P, Lotito A, et al. Clinical and laboratory characteristics of children positive for antiphospholipid antibodies. Blood Transfus. Dec 22 2011;1-6. [Medline].
Muscal E, Brey RL. Antiphospholipid syndrome and the brain in pediatric and adult patients. Lupus. Apr 2010;19(4):406-11. [Medline]. [Full Text].
Cook MC. B cell biology, apoptosis, and autoantibodies to phospholipids. Thromb Res. 2004;114(5-6):307-19. [Medline].
Esmon NL, Safa O, Smirnov MD, Esmon CT. Antiphospholipid antibodies and the protein C pathway. J Autoimmun. Sep 2000;15(2):221-5. [Medline].
Meroni PL, Raschi E, Camera M, et al. Endothelial activation by aPL: a potential pathogenetic mechanism for the clinical manifestations of the syndrome. J Autoimmun. Sep 2000;15(2):237-40. [Medline].
Meroni PL, Raschi E, Testoni C, et al. Antiphospholipid antibodies and the endothelium. Rheum Dis Clin North Am. Aug 2001;27(3):587-602. [Medline].
Rauch J, Subang R, D'Agnillo P, Koh JS, Levine JS. Apoptosis and the antiphospholipid syndrome. J Autoimmun. Sep 2000;15(2):231-5. [Medline].
Angles-Cano E, Guillin MC. Antiphospholipid antibodies and the coagulation cascade. Rheum Dis Clin North Am. Aug 2001;27(3):573-86. [Medline].
Petri M. Pathogenesis and treatment of the antiphospholipid antibody syndrome. Med Clin North Am. Jan 1997;81(1):151-77. [Medline].
Matsuura E, Kobayashi K, Tabuchi M. Accelerated atheroma in the antiphospholipid syndrome. Rheum Dis Clin North Am. Aug 2006;32(3):537-51. [Medline].
Horita T, Atsumi T, Yoshida N, Nakagawa H, Kataoka H, Yasuda S. STAT4 single nucleotide polymorphism, rs7574865 G/T, as a risk for antiphospholipid syndrome. Ann Rheum Dis. Aug 2009;68(8):1366-7. [Medline].
Pierangeli SS, Vega-Ostertag M, Harris EN. Intracellular signaling triggered by antiphospholipid antibodies in platelets and endothelial cells: a pathway to targeted therapies. Thromb Res. 2004;114(5-6):467-76. [Medline].
Meroni PL, Raschi E, Testoni C, Tincani A, Balestrieri G, Molteni R, et al. Statins prevent endothelial cell activation induced by antiphospholipid (anti-beta2-glycoprotein I) antibodies: effect on the proadhesive and proinflammatory phenotype. Arthritis Rheum. Dec 2001;44(12):2870-8. [Medline].
Ferrara DE, Swerlick R, Casper K, Meroni PL, Vega-Ostertag ME, Harris EN, et al. Fluvastatin inhibits up-regulation of tissue factor expression by antiphospholipid antibodies on endothelial cells. J Thromb Haemost. Sep 2004;2(9):1558-63. [Medline].
Ferrara DE, Liu X, Espinola RG, Meroni PL, Abukhalaf I, Harris EN, et al. Inhibition of the thrombogenic and inflammatory properties of antiphospholipid antibodies by fluvastatin in an in vivo animal model. Arthritis Rheum. Nov 2003;48(11):3272-9. [Medline].
López-Pedrera Ch, Buendía P, Aguirre MA, Velasco F, Cuadrado MJ. Antiphospholipid syndrome and tissue factor: a thrombotic couple. Lupus. 2006;15(3):161-6. [Medline].
Redecha P, Franzke CW, Ruf W, Mackman N, Girardi G. Neutrophil activation by the tissue factor/Factor VIIa/PAR2 axis mediates fetal death in a mouse model of antiphospholipid syndrome. J Clin Invest. Oct 2008;118(10):3453-61. [Medline].
Hughson MD, McCarty GA, Brumback RA. Spectrum of vascular pathology affecting patients with the antiphospholipid syndrome. Hum Pathol. Jul 1995;26(7):716-24. [Medline].
Asherson RA, Cervera R, Piette JC. Catastrophic antiphospholipid syndrome. Clinical and laboratory features of 50 patients. Medicine (Baltimore). May 1998;77(3):195-207. [Medline].
Asherson RA, Cervera R, Piette JC. Catastrophic antiphospholipid syndrome: clues to the pathogenesis from a series of 80 patients. Medicine (Baltimore). Nov 2001;80(6):355-77. [Medline].
Cervera R, Asherson RA, Font J. Catastrophic antiphospholipid syndrome. Rheum Dis Clin North Am. Aug 2006;32(3):575-90. [Medline].
Cervera R, Bucciarelli S, Plasin MA, et al. Catastrophic antiphospholipid syndrome (CAPS): descriptive analysis of a series of 280 patients from the "CAPS Registry". J Autoimmun. May-Jun 2009;32(3-4):240-5. [Medline].
Asherson RA, Piette JC. The catastrophic antiphospholipid syndrome 1996: acute multi-organ failure associated with antiphospholipid antibodies: a review of 31 patients. Lupus. Oct 1996;5(5):414-7. [Medline].
Rosenzweig EB, Widlitz AC, Barst RJ. Pulmonary arterial hypertension in children. Pediatr Pulmonol. Jul 2004;38(1):2-22. [Medline].
Moroni G, Ventura D, Riva P. Antiphospholipid antibodies are associated with an increased risk for chronic renal insufficiency in patients with lupus nephritis. Am J Kidney Dis. Jan 2004;43(1):28-36. [Medline].
Nochy D, Daugas E, Huong DL, et al. Kidney involvement in the antiphospholipid syndrome. J Autoimmun. Sep 2000;15(2):127-32. [Medline].
Amigo MC. Kidney disease in antiphospholipid syndrome. Rheum Dis Clin North Am. Aug 2006;32(3):509-22. [Medline].
Daugas E, Nochy D, Huong du LT. Antiphospholipid syndrome nephropathy in systemic lupus erythematosus. J Am Soc Nephrol. Jan 2002;13(1):42-52. [Medline].
Garcia-Martin F, De Arriba G, Carrascosa T. Anticardiolipin antibodies and lupus anticoagulant in end-stage renal disease. Nephrol Dial Transplant. 1991;6(8):543-7. [Medline].
Tektonidou MG, Sotsiou F, Nakopoulou L. Antiphospholipid syndrome nephropathy in patients with systemic lupus erythematosus and antiphospholipid antibodies: prevalence, clinical associations, and long-term outcome. Arthritis Rheum. Aug 2004;50(8):2569-79. [Medline].
Roldan CA, Shively BK, Lau CC, Gurule FT, Smith EA, Crawford MH. Systemic lupus erythematosus valve disease by transesophageal echocardiography and the role of antiphospholipid antibodies. J Am Coll Cardiol. Nov 1 1992;20(5):1127-34. [Medline].
Turiel M, Sarzi-Puttini P, Peretti R, et al. Five-year follow-up by transesophageal echocardiographic studies in primary antiphospholipid syndrome. Am J Cardiol. Aug 15 2005;96(4):574-9. [Medline].
Hojnik M, George J, Ziporen L, Shoenfeld Y. Heart valve involvement (Libman-Sacks endocarditis) in the antiphospholipid syndrome. Circulation. Apr 15 1996;93(8):1579-87. [Medline].
Cervera R. Recent advances in antiphospholipid antibody-related valvulopathies. J Autoimmun. Sep 2000;15(2):123-5. [Medline].
Tenedios F, Erkan D, Lockshin MD. Cardiac manifestations in the antiphospholipid syndrome. Rheum Dis Clin North Am. Aug 2006;32(3):491-507. [Medline].
Soltész P, Szekanecz Z, Kiss E, Shoenfeld Y. Cardiac manifestations in antiphospholipid syndrome. Autoimmun Rev. Jun 2007;6(6):379-86. [Medline].
Yadav D, Chandra J, Sharma S, Singh V. Essential thrombocytosis and antiphospholipid antibody syndrome causing chronic budd-Chiari syndrome. Indian J Pediatr. Apr 2012;79(4):538-40. [Medline].
Espinosa G, Cervera R, Font J, Asherson RA. Adrenal involvement in the antiphospholipid syndrome. Lupus. 2003;12(7):569-72. [Medline].
Brey RL. Differential diagnosis of central nervous system manifestations of the antiphospholipid antibody syndrome. J Autoimmun. Sep 2000;15(2):133-8. [Medline].
Frances C, Piette JC. The mystery of Sneddon syndrome: relationship with antiphospholipid syndrome and systemic lupus erythematosus. J Autoimmun. Sep 2000;15(2):139-43. [Medline].
Muscal E, Brey RL. Neurologic manifestations of the antiphospholipid syndrome: integrating molecular and clinical lessons. Curr Rheumatol Rep. Jan 2008;10(1):67-73. [Medline].
Muscal E, Brey RL. Neurological manifestations of the antiphospholipid syndrome: risk assessments and evidence-based medicine. Int J Clin Pract. Sep 2007;61(9):1561-8. [Medline].
Bertolaccini ML, Hughes GR. Antiphospholipid antibody testing: which are most useful for diagnosis?. Rheum Dis Clin North Am. Aug 2006;32(3):455-63. [Medline].
Carreras LO, Forastiero RR, Martinuzzo ME. Which are the best biological markers of the antiphospholipid syndrome?. J Autoimmun. Sep 2000;15(2):163-72. [Medline].
Derksen RH, de Groot PG. Tests for lupus anticoagulant revisited. Thromb Res. 2004;114(5-6):521-6. [Medline].
Exner T. Conceptions and misconceptions in testing for lupus anticoagulants. J Autoimmun. Sep 2000;15(2):179-83. [Medline].
Galli M. Should we include anti-prothrombin antibodies in the screening for the antiphospholipid syndrome?. J Autoimmun. Sep 2000;15(2):101-5. [Medline].
Gilman-Sachs A, Lubinski J, Beer AE, et al. Patterns of anti-phospholipid antibody specificities. J Clin Lab Immunol. Jun 1991;35(2):83-8. [Medline].
Mcintyre JA, Wagenknecht DR. Anti-phosphatidylethanolamine (aPE) antibodies: a survey. J Autoimmun. Sep 2000;15(2):185-93. [Medline].
Merrill JT. Which antiphospholipid antibody tests are most useful?. Rheum Dis Clin North Am. Aug 2001;27(3):525-49. [Medline].
Petri M. Diagnosis of antiphospholipid antibodies. Rheum Dis Clin North Am. May 1994;20(2):443-69. [Medline].
Pierangeli SS, Harris EN. Advances in antiphospholipid antibody testing. Clin Appl Immunol Rev. 2000;1:59-72.
Rapizzi E, Ruffatti A, Tonello M, et al. Correction for age of anticardiolipin antibodies cut-off points. J Clin Lab Anal. 2000;14(3):87-90. [Medline].
Tincani A, Allegri F, Balestrieri G. Minimal requirements for antiphospholipid antibodies ELISAs proposed by the European Forum on antiphospholipid antibodies. Thromb Res. 2004;114(5-6):553-8. [Medline].
Tincani A, Balestrieri G, Allegri F, et al. Overview on anticardiolipin ELISA standardization. J Autoimmun. Sep 2000;15(2):195-7. [Medline].
Triplett DA. Antiphospholipid-protein antibodies: laboratory detection and clinical relevance. Thromb Res. Apr 1 1995;78(1):1-31. [Medline].
Triplett DA. Use of the dilute Russell viper venom time (dRVVT): its importance and pitfalls. J Autoimmun. Sep 2000;15(2):173-8. [Medline].
Wong RC. Consensus guidelines for anticardiolipin antibody testing. Thromb Res. 2004;114(5-6):559-71. [Medline].
Noda S, Ogura M, Tsutsumi A, Udagawa T, Kamei K, Matsuoka K, et al. Thrombotic microangiopathy due to multiple autoantibodies related to antiphospholipid syndrome. Pediatr Nephrol. Apr 2012;27(4):681-5. [Medline].
Khamashta MA. Primary prevention of thrombosis in subjects with positive antiphospholipid antibodies. J Autoimmun. Sep 2000;15(2):249-53. [Medline].
Khamashta MA, Cuadrado MJ, Mujic F, et al. The management of thrombosis in the antiphospholipid-antibody syndrome. N Engl J Med. Apr 13 1995;332(15):993-7. [Medline].
Petri M. Management of thrombosis in antiphospholipid antibody syndrome. Rheum Dis Clin North Am. Aug 2001;27(3):633-42, viii. [Medline].
Rai R. Obstetric management of antiphospholipid syndrome. J Autoimmun. Sep 2000;15(2):203-7. [Medline].
[Best Evidence] Galie N, Ghofrani HA, Torbicki A, et al. Sildenafil citrate therapy for pulmonary arterial hypertension. N Engl J Med. Nov 17 2005;353(20):2148-57. [Medline].
Humpl T, Reyes JT, Holtby H. Beneficial effect of oral sildenafil therapy on childhood pulmonary arterial hypertension: twelve-month clinical trial of a single-drug, open-label, pilot study. Circulation. Jun 21 2005;111(24):3274-80. [Medline].
Rosenzweig EB, Ivy DD, Widlitz A. Effects of long-term bosentan in children with pulmonary arterial hypertension. J Am Coll Cardiol. Aug 16 2005;46(4):697-704. [Medline].
Derksen RH, de Groot PG. Do we Know which Patients with the Antiphospholipid Syndrome Should Receive Long-term High Dose Anti-coagulation?. J Autoimmun. Sep 2000;15(2):255-259. [Medline].
Wald DS, Bishop L, Wald NJ, et al. Randomized trial of folic acid supplementation and serum homocysteine levels. Arch Intern Med. Mar 12 2001;161(5):695-700. [Medline].
Erkan D, Lockshin MD. New approaches for managing antiphospholipid syndrome. Nat Clin Pract Rheumatol. Mar 2009;5(3):160-70. [Medline].
Lockshin M, Tenedios F, Petri M, McCarty G, Forastiero R, Krilis S. Cardiac disease in the antiphospholipid syndrome: recommendations for treatment. Committee consensus report. Lupus. 2003;12(7):518-23. [Medline].
Levine SR, Brey RL, Tilley BC, et al. Antiphospholipid antibodies and subsequent thrombo-occlusive events in patients with ischemic stroke. JAMA. Feb 4 2004;291(5):576-84. [Medline].
Belizna CC, Richard V, Thuillez C, Levesque H, Shoenfeld Y. Insights into atherosclerosis therapy in antiphospholipid syndrome. Autoimmun Rev. Nov 2007;7(1):46-51. [Medline].
Takemoto CM. Rituximab for ITP: a long-term fix?. Pediatr Blood Cancer. Feb 2009;52(2):155-6. [Medline].
Semple JW. ITP three R's: regulation, routing, rituximab. Blood. Aug 15 2008;112(4):927-8. [Medline].
Marks SD, Patey S, Brogan PA, et al. B lymphocyte depletion therapy in children with refractory systemic lupus erythematosus. Arthritis Rheum. Oct 2005;52(10):3168-74. [Medline].
Asherson RA, Chan JK, Harris EN, et al. Anticardiolipin antibody, recurrent thrombosis, and warfarin withdrawal. Ann Rheum Dis. Dec 1985;44(12):823-5. [Medline].
Lawrie AS, Purdy G, Mackie IJ, Machin SJ. Monitoring of oral anticoagulant therapy in lupus anticoagulant positive patients with the anti-phospholipid syndrome. Br J Haematol. Sep 1997;98(4):887-92. [Medline].
Moll S, Ortel TL. Monitoring warfarin therapy in patients with lupus anticoagulants. Ann Intern Med. Aug 1 1997;127(3):177-85. [Medline].
Pauzner R, Greinacher A, Selleng K, Althaus K, Shenkman B, Seligsohn U. False-positive tests for heparin-induced thrombocytopenia in patients with antiphospholipid syndrome and systemic lupus erythematosus. J Thromb Haemost. Jul 2009;7(7):1070-4. [Medline].
Alarcon-Segovia D, Perez-Ruiz A, Villa AR. Long-term prognosis of antiphospholipid syndrome in patients with systemic lupus erythematosus. J Autoimmun. Sep 2000;15(2):157-61. [Medline].
Amigo MC. Prognosis in antiphospholipid syndrome. Rheum Dis Clin North Am. Aug 2001;27(3):661-9. [Medline].
Erkan D, Asherson RA, Espinosa G, et al. Long term outcome of catastrophic antiphospholipid syndrome survivors. Ann Rheum Dis. Jun 2003;62(6):530-3. [Medline].

