The onset of DIC can be sudden, as in endotoxic shock or amniotic fluid embolism, or it may be insidious and chronic, as in cancer.

[10] Under homeostatic conditions, the body is maintained in a finely tuned balance of coagulation and fibrinolysis.

Activation of the fibrinolytic system generates plasmin (in the presence of thrombin), which is responsible for the lysis of fibrin clots.

This complex further activates factor IX and X to IXa and Xa, respectively, leading to the common coagulation pathway and the subsequent formation of thrombin and fibrin.

Other malignancies may enhance the expression of various oncogenes that result in the release of TF and plasminogen activator inhibitor-1 (PAI-1), which prevents fibrinolysis.

The excess thrombin cleaves fibrinogen, which ultimately leaves behind multiple fibrin clots in the circulation.

The breakdown of clots results in an excess of FDPs, which have powerful anticoagulant properties, contributing to hemorrhage.

Activation of these systems leads to many of the clinical symptoms that patients experiencing DIC exhibits, such as shock, hypotension, and increased vascular permeability.

The acute form of DIC is considered an extreme expression of the intravascular coagulation process with a complete breakdown of the normal homeostatic boundaries.

The hemorrhage observed in DIC and among some tissues lacking this receptor may therefore be secondary to increased thrombosis with loss of the mechanical vascular barrier.

[14][15] Activation of the intrinsic and extrinsic coagulation pathways causes excess thrombus formation in the blood vessels.

Laboratory markers consistent with DIC include:[3][7][17] A diagnostic algorithm has been proposed by the International Society of Thrombosis and Haemostasis.

Transfusions of platelets or fresh frozen plasma can be considered in cases of significant bleeding, or those with a planned invasive procedure.

[citation needed] Recombinant human activated protein C was previously recommended in those with severe sepsis and DIC, but drotrecogin alfa has been shown to confer no benefit and was withdrawn from the market in 2011.

[21] Recombinant factor VII has been proposed as a "last resort" in those with severe hemorrhage due to obstetric or other causes, but conclusions about its use are still insufficient.