DIC

Question 1

Causes of DIC?

Answer 1

• Infection and severe sepsis
• Malignancy - solid tumours or haem malignancies
• Trauma e.g. major surgery, burns, shock, dissecting aortic aneurysm
• Liver disease
• Obstetric complications - e.g. amnotic fluid embolism, HELLP, placental abruption, preeclampsia
• (Multiple organ failure)
• ABO transfusion incompatibilty

Note: Acute promyelocytic leukaemia (APL) is an uncommon subtype of acute myelogenous leukaemia that is associated with DIC. This comes up frequently in written exams

Question 2

Pathophsiology of DIC?

Answer 2

Normally = coagulation and fibrinolysis are coupled.
In DIC = dysregulated process of coag and fibrinolysis
* causes widespread clotting with bleeding
* mediated by release of tissue factor (TF) - normally on surface in cells, but not in general circulation.
* In DIC, there is vascular damage = this exposes TF to circulation
* once activated, TF binds with coag factors that trigger extrinisc pathway, which then triggers intrinsic pathway of coagulation.

Question 3

What are inv findings for DIC?

Answer 3

• Low platelets
• Prolonged APTT, prothrombin and bleeding time
• Fibrin degradation products are often raised
• Schistocytes due to microangiopathic haemolytic anaemia

Question 4

Management of DIC if bleeding is predominant feature

Answer 4