The typical clinical picture of APS is characterised by:
Deep venous thrombosis (DVT) is the most common clinical sign.
Cerebrovascular accidents are the most frequent signs of arterial thrombosis.
Foetal loss, both early and late, premature delivery and pre-eclampsia are the most common obstetric signs.
Unlike persistent antiphospholipid antibodies, clinical signs are rare.
In addition to thrombotic signs, APS can cause neurological disorders such as impaired cognitive function or signs of demyelination not directly related to thrombotic lesions.
Catastrophic antiphospholipid syndrome is a rare (< 1% of cases of APS) but extremely serious form of APS. It is associated with multiple small vessel thromboses leading to life-threatening multiple organ failure.