ABSTRACT
The etiology of venous thromboembolic disease has been the subject of several recent
discoveries, particularly on genetic predisposing factors. The laboratory investigation
that may help to evaluate the risk for individual patients includes the measurements
of coagulation inhibitors (antithrombin, protein C, and protein S) in plasma assays,
the search for the factor V Leiden mutation by the plasma activated protein C resistance
test (always to be confirmed by DNA analysis when abnormal), and the search for the
prothrombin gene mutation by DNA analysis. Among acquired abnormalities, the most
frequently involved are phospholipid-dependent autoantibodies associated or not with
a subset of antibodies having an anticoagulant effect in vitro (lupus anticoagulant).
Other coagulation abnormalities such as increased FVIII, FIX, or FXI levels or hyperhomocysteinemia
have been suggested to be risk factors for thrombosis, although additional studies
are required to definitively assess their role.
KEYWORD
Thrombophilia - deep vein thrombosis - laboratory investigation
