Antiphospholipid syndrome

Antiphospholipid syndrome is a systemic autoimmune disorder. It is usually defined as the clinical complex of vascular occlusion and ischaemic events occurring in patients who have circulating antiphospholipid antibodies.


Patients have circulating antiphospholipid antibodies cross-react with cell membrane phospholipids. This results in a hypercoagulable state leading to vascular thrombosis. It can affect multiple organ systems:


The disorder can be primary (primary antiphospholipid syndrome) or secondary (i.e. associated with systemic lupus erythematosus).


Paradoxically, a patient's coagulation profile will show an elevated aPTT suggesting a propensity to bleeding, however this is not the case. Positive lupus anticoagulant, anticardiolipin antibodies, and anti-beta2-glycoprotein I antibodies are seen but are not specific for antiphospholipid syndrome 6.

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Article information

rID: 26162
Section: Syndromes
Tag: stub, cases
Synonyms or Alternate Spellings:
  • Anti-phopholipid antibody syndrome
  • Antiphospholipid syndrome (APS)
  • Hughes syndrome
  • Anti-phopholipid syndrome
  • APLA syndrome
  • Anti phospholipid antibody syndrome

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Cases and figures

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    Case 1: diffuse alveolar haemorrhage
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