Antiphospholipid Syndrome (APS)

Question 1

What is antiphospholipid syndrome (APS)?

Answer 1

Associated with antiphospholipid antibodies where blood becomes prone to clotting = hyper-coagulable state.
Can occur on its own or 2˚ to AI disorder (esp. SLE).

Question 2

Antiphospholipid syndrome is often characterised by 2 key clinical features. What are they?

Answer 2

1. Thrombosis (arterial or venous)
2. Recurrent miscarriages due to blood clots and with positive blood tests for antiphospholipid antibodies (aPL)

Question 3

Briefly describe the pathophysiology of antiphospholipid syndrome (APL).

Answer 3

1. Antiphospholipid antibodies (aPL) play a role in thrombosis by binding to
   phospholipid on the surface of cells such as endothelial cells, platelets and
   monocytes.
2. Once bound, this change alters the functioning of those cells leading to
   thrombosis and/or miscarriage

Question 4

What are the 4 characteristic clinical features of anti-phospholipid syndrome?

Answer 4

Antiphospholipid antibodies (aPL) cause CLOTs:

• C - Coagulation defect
• L - Livedo reticularis - lace-like purplish discolouration of skin
• O - Obstetric issues i.e. miscarriages
• T - Thrombocytopenia (low platelets)

Question 5

Give 4 risk factors for antiphospholipid syndrome.

Answer 5

1. HTN
2. Diabetes
3. Obesity
4. Female sex
5. Underlying systemic AI disease
6. Smoking
7. Oestrogen therapy for menopause

Question 6

Describe the clinical presentation of antiphospholipid syndrome - give 4 symptoms.

Answer 6

Relating to CLOT:
1. Thrombosis
2. Miscarriage
3. Ischaemic stroke, TIA, MI - arteries
4. Deep vein thrombosis, Budd-chiari syndrome - veins
5. Thrombocytopenia
6. Valvular heart disease, migraines, epilepsy

Question 7

What are the 3 diagnostic investigations to be carried out in APS?

Answer 7

1. Lupus anticoagulation test
2. Anti-beta2 glycoprotein test
3. Anticardiolipin test

Indicate +ve blood test for antiphospholipid antibodies.

Question 8

Investigations: what does the lupus anticoagulation test do?

Answer 8

Detects changes in the ability of the blood to clot

Question 9

Investigations: what does the anticardiolipin test do?

Answer 9

Detects IgG or IgM antibodies that bind the negatively charged phospholipid - cardiolipin

Question 10

Investigations: what does the anti-beta2 glycoprotein I test do?

Answer 10

Detects antibodies that bind B2-glycoprotein I, a molecule that interacts
closely with phospholipids

Question 11

How would you manage a patient with antiphospholipid syndrome - not pregnant?

Answer 11

1. Long term WARFARIN
   -To minimise thrombosis

Question 12

How would you manage a patient who has high IgG aPL but is asymptomatic for APS?

Answer 12

Prophylaxis:
- For those with high IgG aPL (antiphospholipid antibody) but asymptomatic
* Give ASPIRIN or CLOPIDOGREL

Question 13

How would you manage a pregnant patient with APS?

Answer 13

1. Long term WARFARIN
   - To minimise thrombosis
2. Pregnant women:
   * ORAL ASPIRIN and SC LMW HEPARIN early on in pregnancy
   - e.g. enoxaparin
   * Reduces chance of miscarriage but pre-eclampsia and poor foetal growth remain common

Question 14

Give some examples of complications of APS.

Answer 14

Venous thromboembolisms (e.g. DVT, pulmonary embolism)
Arterial thrombosis (stroke, MI, renal thrombosis)
Pregnancy complications (recurrent miscarriage, pre-eclampsia)