Overview of antiphospholipid syndrome

Tektonidou, 2019

Antiphospholipid syndrome is a systemic autoimmune condition characterised by arterial or venous thromboembolism, or pregnancy-related complications, associated with persistent antiphospholipid (aPL) antibodies. It usually affects younger people (under 50 years). There are two syndromes (phenotypes) that may coexist:

  • thrombotic antiphospholipid syndrome—persistent aPL antibodies associated with arterial or venous thromboembolism at a young age
  • obstetric antiphospholipid syndrome—persistent aPL antibodies associated with pregnancy-related complications.

There may be some crossover of these 2 main phenotypes, depending on the person’s aPL-antibody profile or whether the person has concomitant cardiovascular risk factors, or systemic lupus erythematosus (SLE)de Jesus, 2019Jiang, 2021Spaanderman, 2019Tonello, 2021.

Antiphospholipid syndrome may present as a primary condition (ie without any additional disease association) or a secondary condition associated with other inflammatory connective tissue diseases. SLE is the most common condition associated with antiphospholipid syndrome; less frequently Sjögren syndrome, rheumatoid arthritis and systemic sclerosis may be associated.