Antiphospholipid Syndrome (APS)

Question 1

what is antiphospholipid syndrome (APS)?

Answer 1

• an autoimmune disorder that is characterised by arterial, venous, or microvascular thrombosis or recurrent pregnancy loss
• it is caused by antibodies directed against one or more phospholipid-bound proteins (e.g. beta-2 glycoprotein 1, prothrombin, annexin A5)

Question 2

what are the clinical manifestations of APS?

Answer 2

• arterial/venous thrombosis
• recurrent pregnancy loss
• thrombocytopenia
• haemolytic anaemia
• thrombotic microangiopathy

Question 3

what is catastrophic antiphospholipid syndrome (CAPS)?

Answer 3

in a small proportion of patients with APS, widespread thromboses occur in small vessels supplying multiple organs, often including the brain

Question 4

what are the clinical manifestations of CAPS?

Answer 4

• multiorgan failure
• AKI
• encephalopathy
• adrenal haemorrhage
• skin necrosis
• diffuse alveolar haemorrhage

Question 5

what is the treatment for CAPS?

Answer 5

• high-dose corticosteroids
• anticoagulation
• plasmapheresis
• ? rituximab/eculizumab

Question 6

what are the investigations for APS?

Answer 6

• ↑ PTT
• dilute russell viper venom time (DRVVT)
• immunoassays for IgG and IgM antibodies against cardiolipin and beta-2 glycoprotein 1

Question 7

what is the management of APS?

Answer 7

• anticoagulation (e.g. warfarin)
• unfractionated heparin/low-molecular weight heparin + low-dose aspirin (e.g. pregnancy)