#132 Antiphospholipid Syndrome

Question 1

What % of people with antiphospholipid syndrome are female?

Answer 1

70%

Question 2

What is the role of beta2-glycoprotein I?

Answer 2

Regulatory role in coagulation, fibrinolysis, and other physiologic systems

Question 3

What medical/obstetrical problems are associated with antiphospholipids antibodies?

Answer 3

Arterial thrombosis, venous thrombosis, autoimmune thrombocytopenia, fetal loss, preeclampsia, IUGR, placental insufficiency, preterm delivery, hemolytic anemia, amaurosis fugax, livedo reticularis, SLE, false-positive RPR

Question 4

What antiphospholipid antibodies contribute to the diagnosis of antiphospholipid syndrome?

Answer 4

1. Lupus anticoagulant
2. Anticardiolipin
3. anti-beta2-glycoprotein I

Question 5

Which antibody associated with antiphospholipid syndrome is most specific?

Answer 5

Lupus anticoagulant. But it is less sensitive than the other two.

Question 6

Do you need all three antibodies to be diagnosed with antiphospholipid syndrome?

Answer 6

No.

Question 7

What are laboratory criteria for diagnosis of antiphospholipid syndrome?

Answer 7

1. Lupus anticoagulant present in plasma on two or more occasions at least 12 weeks apart (when no on anticoagulants)
2. Anticardiolipin antibody IgG and/or IgM >99%tile on two or more occasions at least 12wks apart
3. Anti-beta2-glycoprotein I IgG and/or IgM >99%tile on two or more occasions at least 12wks apart

Question 8

How do you screen for lupus anticoagulant?

Answer 8

Combination of sensitive clotting assays, such as lupus anticoagulant-sensitive activated PTT and dilute Russell’s viper venom time

Question 9

Which isotypes of anticardiolipin antibodies matter?

Answer 9

IgG and IgM. Clinical relevance of IgA is uncertain

Question 10

What test is used to measure anticardiolipin antibodies?

Answer 10

Enzyme-linked immunosorbent assay

Question 11

What test is used to measure anti-beta2-glycoprotein I?

Answer 11

Enzyme-linked immunosorbent assay

Question 12

What is considered a positive anti-beta2-glycoprotein antibody test?

Answer 12

> 99th percentile

Question 13

What percentage of patients with venous thrombosis will test positive for lupus anticoagulant antibodies?

Answer 13

2%

Question 14

What is the risk of thrombosis during pregnancy or puerperium in women with antiphospholipid syndrome?

Answer 14

5-12%

Question 15

What is the most common consequence of an arterial occlusion?

Answer 15

Stroke

Question 16

What percentage of individuals <50yo (otherwise healthy) with stroke have antiphospholipid antibodies?

Answer 16

4-6%

Question 17

What percentage of individuals with antiphospholipid syndome will have autoimmune thrombocytopenia?

Answer 17

40-50%

Question 18

Is thombocytopenia from antiphospholipid syndrome vs immune thrombocytopenic purpura treated differently?

Answer 18

No, same therapy. steroids. immune globulin.

Question 19

What is the definition of the fetal period?

Answer 19

Greater than 10wks

Question 20

What % of pregnancy losses occur during the fetal period (>10wk) in women with antiphospholipid antibodies vs general population?

Answer 20

50% vs 10%

Question 21

What % of women with antiphospholipid antibodies had at least one fetal death compared to those without antibodies?

Answer 21

84% vs 24%

Question 22

What percentage of women with recurrent pregnancy loss test positive for antiphospholipid antibodies?

Answer 22

5-20%. Not known if these cases would meet current international criteria for APLS

Question 23

What percentage of women with preeclampsia test positive for antiphospholipid antibodies?

Answer 23

11-17%

Question 24

What percentage of pregnancies in women with APLS are IUGR?

Answer 24

15-30%

Question 25

What are clinical criteria for diagnosis of APLS?

Answer 25

1. vascular thrombosis: one or more clinical episodes of arterial, venous, or small vessel thrombosis or 2. Pregnancy morbidity: - one or more unexplained deaths of normal fetus at or beyond 10wks, or - one or more premature births of normal neonate before 34wks d/t SPEC, eclampsia, placental insufficiency, or - three or more unexplained consecutive spontaneous pregnancy losses before 10th week

Question 26

How should a women with APLS w/ hx thrombosis be managed during pregnancy?

Answer 26

Prophylactic anticoagulation with heparin throughout pregnancy and 6wks postpartum. Many people add ASA, but benefit is unknown

Question 27

How should you treat women with APLS without hx of thrombosis?

Answer 27

Clinical surveillance or prophylactic heparin antepartum in addition to 6wk postpartum

Question 28

How should women with APLS and recurrent pregnancy loss be managed?

Answer 28

Prophylactic heparin and low-dose ASA. May reduce pregnancy loss by 50%

Question 29

Is antepartum surveillance (fetal testing) recommended for patients with APLS?

Answer 29

Many experts recommend serial ultrasound assessment and antepartum testing in 3rd trimester. Data insufficient to support or refute specific practice.

Question 30

Is APLS a contraindication to estrogen-containing contraceptives?

Answer 30

Yes.