Antiphospholipid syndrome

Question 1

What is antiphospholipid syndrome?

Answer 1

An acquired disorder characterised by a predisposition to both venous and arterial thromboses, recurrent fetal loss and thrombocytopenia

Question 2

What can paradoxically rise in antiphospholipid syndrome?

Answer 2

There can be a paradoxical rise in APTT.

This is due to an ex-vivo reaction of the lupus anticoagulant autoantibodies with phospholipids involved in the coagulation cascade

Question 3

Symptoms?

Answer 3

• venous/arterial thrombosis
• recurrent fetal loss
• livedo reticularis
• other features: pre-eclampsia, pulmonary hypertension

Question 4

What is low in the blood?

Answer 4

There is thrombocytopenia aka deficiency of platelets

Question 5

What is this condition associated with?

Answer 5

• SLE
• other autoimmune disorders
• lymphoproliferative disorders
• phenothiazines (rare)

Question 6

Management for primary thromboprophylaxis?

Answer 6

Low-dose aspirin

Question 7

Management for secondary thromboprophylaxis (initial venous thromboembolic events):

Answer 7

Lifelong warfarin with a target INR of 2-3

Question 8

Management for secondary thromboprophylaxis (recurrent venous thromboembolic events):

Answer 8

Lifelong warfarin; if occurred whilst taking warfarin then consider adding low-dose aspirin, increase target INR to 3-4

Question 9

Management for secondary thromboprophylaxis (arterial thrombosis):

Answer 9

Treat with lifelong warfarin with target INR 2-3

Question 10

How may this condition occur?

Answer 10

It may occur as a primary disorder or secondary to other conditions, most commonly systemic lupus erythematosus (SLE)