Page 2353 - Hematology_ Basic Principles and Practice ( PDFDrive )

Chapter 141 The Antiphospholipid Syndrome 2095

TABLE Laboratory Interpretation in Antiphospholipid Syndrome Diagnosis and Treatment*
141.4
Risk Laboratory Result a Clinical Manifestation Treatment
High risk Triple positive for LA, aCL Venous thromboembolism Long-term vitamin K antagonist, INR 2.0–3.0
OR>9 (IgG or IgM >40 GPL) Arterial thromboembolism Stroke: Long-term vitamin K antagonist, INR 2.0–3.0 plus aspirin 100 mg
and anti-β 2 GPI (IgG or IgM per day
>99th percentile) Myocardial infarction: Long-term vitamin K antagonist, INR 2.0–3.0 plus
aspirin 100 mg per day
or
Long-term vitamin K antagonist, INR 3.0–4.0
Myocardial infarction with percutaneous coronary interventions and stent
placement: Long-term vitamin K antagonist, INR 2.0–3.0, aspirin
100 mg per day, and clopidogrel 75 mg per day
Pregnant women with history of Unfractionated heparin plus low-dose aspirin
pregnancy complications or
thrombotic events
Asymptomatic Consider anticoagulant prophylaxis for high risk situations, e.g.,
immobilization, surgery, air travel
Consider long-term vitamin K antagonist recommended to prevent
thromboembolic events
Consider low-dose aspirin and possible unfractionated heparin for pregnant
patients
Medium risk Double positive for LA, aCL Venous thromboembolism Long-term vitamin K antagonist, INR 2.0–3.0
OR 5–9 (IgG or IgM >40 GPL) Arterial thromboembolism Long-term vitamin K antagonist, INR 2.0–3.0 plus aspirin 100 mg per day
or anti-β 2 GPI (IgG or IgM
>99th percentile) Pregnant women with history of Unfractionated heparin plus low-dose aspirin
or pregnancy complications
Single positive for LA Asymptomatic No treatment, consider prophylaxis treatment in situations with increased
risk: surgery or prolonged immobilization
Low risk Single positive for aCL (IgG Venous thromboembolism Long-term vitamin K antagonist, INR 2.0–3.0
OR 1–5 or IgM >40 GPL) or Arterial thromboembolism Long-term vitamin K antagonist, INR 2.0–3.0
anti-β 2 GPI (IgG or IgM
>99th percentile) b Pregnant women with history of Early miscarriage (does not meet clinical criteria for obstetric APS): consider
pregnancy complications low-dose aspirin
Late miscarriage: unfractionated heparin plus low-dose aspirin
Asymptomatic No treatment; however, consider prophylaxis treatment in situations with
increased risk: surgery or prolonged immobilization
a Laboratory tests should be deferred until at least 12 weeks after the clinical event to avoid interferences of the acute phase of the disease. Earlier testing may yield false
positive results.
b More information from clinical studies on homogeneous cohort of patients with single positivity is needed.
aCL, Anticardiolipin; β 2GPI, β 2-glycoprotein I; Ig, immunoglobulin; INR, international normalized ratio; LA, lupus anticoagulant; OR, odds ratio.
*Adapted from Sciascia S, Cosseddu D, Montaruli B et al: Risk scale for the diagnosis of antiphospholipid syndrome. Ann Rheum Dis 70:1517–1518, 2011; Pengo V,
Banzato A, Bison E, et al: Antiphospholipid syndrome: critical analysis of the diagnostic path. Lupus 19:428, 2010; Pengo V, Ruffatti A, Legnani C et al: Incidence of a
first throboembolic event in asymptomatic carriers of high risk antiphospholipid antibody profile: a mulitcenter prospective study. Blood 118:4714, 2011; Tripodi A, de
Groot PG, Pengo V: Antiphospholipid syndrome: laboratory detection, mechanisms of action and treatment. J Intern Med 270:110, 2011.

independent risk factors for thrombosis, and 3 other studies showed with APS and LA. Additional studies are needed to confirm these
that antiprothrombin antibodies added to the risk borne by LA or findings.
aCL antibodies. However, 29 of the aforementioned studies did not
demonstrate an association between antiprothrombin antibodies and
risk of thrombosis. CLINICAL MANIFESTATIONS OF THE
ANTIPHOSPHOLIPID SYNDROME
Antiphosphatidylserine Antibody Assay The clinical manifestations of APS can be categorized into criteria
manifestations and noncriteria manifestations. The criteria manifes-
Cardiolipin is normally present in mitochondrial membranes and tations include thrombotic events, obstetric APS, and CAPS, and the
probably does not become exposed to plasma coagulation proteins noncriteria manifestations include other pathologic conditions that
in vivo. It was hypothesized that immunoassays for antibodies have been associated with aPL antibodies but have not been included
against phosphatidylserine may be more relevant because this anionic in the definition of “definite APS” by the expert consensus groups.
phospholipid is expressed on apoptotic cells, activated platelets, and
syncytial cells. Although some studies have shown a relationship
between antiphosphatidylserine antibodies and pregnancy complica- Criteria Manifestations of Antiphospholipid Syndrome
tions, mainly recurrent miscarriages and reproductive failure, others
have not. However, in arterial thrombosis, antiphosphatidylserine Systemic Vascular Thrombosis
antibodies have been shown to correlate with APS better than aCL
antibodies. Additionally, it was reported that antibodies against the Thrombosis in APS may occur spontaneously or in the presence of
phosphatidylserine–prothrombin complex (aPS/PT) were associated predisposing factors such as estrogen therapy, oral contraceptives,