Thrombophilia
Thrombophilia is an inherited or acquired tendency to thrombosis. Testing is selective because most heritable results do not change anticoagulation decisions, whereas antiphospholipid syndrome can alter the choice of anticoagulant, pregnancy management and long-term follow-up.
Definition
Thrombophilia is an inherited or acquired tendency to thrombosis caused by altered coagulation, natural anticoagulant or antiphospholipid pathways. It is a risk modifier rather than a diagnosis that, by itself, determines whether a person needs lifelong anticoagulation.
First principles
Thrombosis reflects a balance of risks, not one laboratory label
Venous thrombosis occurs when procoagulant drive outweighs natural anticoagulant and fibrinolytic protection in the context of a person's acquired and inherited risks. Surgery, immobility, cancer, pregnancy, oestrogen and inflammation can combine with a heritable tendency, so a thrombophilia result must be interpreted alongside the clinical event.
This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.

