Antiphospholipid syndrome

• Antiphospholipid syndrome is an autoimmune disorder caused by antiphospholipid antibodies.
• Antiphospholipid antibodies target the proteins that bind to the phospholipids on the cell surface, causing inflammation and increasing the risk of thrombosis 
• It can occur in isolation or associated with another autoimmune condition, particularly systemic lupus erythematosus.
• The specific antiphospholipid antibodies are:

  • Lupus anticoagulant
  • Anticardiolipin antibodies
  • Anti-beta-2 glycoprotein I antibodies
• The key complications of antiphospholipid syndrome are:

  • Venous thromboembolism (e.g., deep vein thrombosis and pulmonary embolism)
  • Arterial thrombosis (e.g., stroke, myocardial infarction and renal thrombosis)
  • Pregnancy-related complications (e.g., recurrent miscarriage, stillbirth and pre-eclampsia)
• Catastrophic antiphospholipid syndrome is a rare complication with rapid thrombosis in multiple organs within a few days. This has a high mortality rate. 
• look out for the patient with thrombosis (e.g., deep vein thrombosis or stroke) and a history of recurrent miscarriage. The diagnosis is likely antiphospholipid syndrome.
• Associations:

  • Livedo racemosa - purple reticular (lace like) rash
  • Libmann-Sacks endocarditis - non bacterial endocarditis
  • Thrombocytopenia
• Diagnosis is based on clinical features and persistent antiphospholipid antibodies.
• Management:

  • Long term warfarin with a target INR of 2-3
  • LMWH and aspirin are used in pregnancy - warfarin is contraindicated