Anti-Phospholipid Syndrome

Question 1

Define Anti-Phospholipid Syndrome

Answer 1

Characterised by the presence of antiphospholipid antibodies (APL) in the plasma, with clinical features such as venous and arterial thromboses, recurrent foetal loss and thrombocytopenia

Question 2

Aetiology of Anti-Phospholipid Syndrome

Answer 2

Presence of persistently elevated antiphospholipid antibodies (aPL) to various phospholipid-binding plasma proteins that are bound to anionic phospholipids (beta2-glycoprotein-l)

May develop in susceptible individuals e.g. rheumatic diseases like SLE after exposure infectious agents

Once present, a “second-hit” is needed for development of the syndrome

Question 3

Epidemiology of Anti-Phospholipid Syndrome

Answer 3

More common in young females
Accounts for 20% of strokes in <45 patients
Accounts for 27% of women with >2 miscarriages

Question 4

Symptoms of Anti-Phospholipid Syndrome

Answer 4

History of:
Recurrent miscarriages
Arterial thromboses e.g. stroke
Venous thromboses e.g. DVT, PE

Headaches (migraine)
Chorea
Epilepsy 
Thrombocytopenia: bruising 
Arthralgia/arthritis 
Limb discomfort, swelling, skin discoloration, ulcers

Question 5

Signs of Anti-Phospholipid Syndrome on examination

Answer 5

Livedo reticularis: mottled purplish discoloration of the skin (blanching or non-blanching)
Signs of SLE (malar flush, discoid lesions, photosensitivity)
Signs of valvular heart disease (cardiac murmurs)
Oedema

Question 6

Investigations for Anti-Phospholipid Syndrome

Answer 6

Anti-cardiolipin antibody of IgG or IgM (ELISA): elevated on 2 occasions 12 weeks apart
Anti-beta2-glycoprotein I antibody: elevated on 2 occasions 12 weeks apart

FBC: thrombocytopenia
ESR: normal
U+Es: Cr and U in APL nephropathy 
Clotting: raised APTT
Lupus anticoagulant assay: elevated on 2 occasions 12 weeks apart 
ANA, ds-DNA: SLE