Disseminated Intravascular Coagulation

Page 1 2 3

What is Disseminated Intravascular Coagulation?

Disseminated intravascular coagulation (DIC) is a disorder that affects the blood clotting cascade. This disorder occurs when your body's clotting mechanisms are activated inappropriately. DIC can occur in the short or long term, and is the end complication of a variety of diseases such as cancers and some infections. Clots form throughout the whole body, instead of localizing only to the site of injury. Eventually, all the blood clotting factors are used up and unavailable to be used when needed at actual sites of injury. In the image on the right severe bleeding has occured in an infant, leading to gangrene within the affected limb.

Who gets Disseminated Intravascular Coagulation?

Disseminated intravascular coagulation often presents with a subacute thrombotic picture in cancer patients, and is associated with high mortality rates when this acutely develops into the haemorrhagic form.

Disseminated intravascular coagulation occurs in 7-10% of patients with malignant disease. Adenocarcinomas and leukaemias are the most common cancer associations.

Predisposing Factors

About 50% of individuals with disseminated intravascular coagulation are patients with complications from pregnancy. Widespread infection and trauma are responsible for the majority of the remaining cases.

There are many causes of disseminated intravascular coagulation. These can be classified as acute or chronic, systemic or localized. The disorder may be the result of single or multiple conditions.

Acute DIC:

Infectious:

Bacterial (eg: gram-negative infections, meningococcal disease)
Viral (eg, HIV,
cytomegalovirus [CMV], varicella)
Fungal (eg, histoplasma)
Parasitic (eg, malaria )

Malignant disease:

Those originating in cells of the bloodstream (eg, acute myelocytic leukemias)
Spread of cancers

Obstetric:

Placental abruption (early separation of a normal placenta from the wall of the uterus
Eclampsia (a serious complication of pregnancy characterized by convulsions.)

Trauma

Burns

Surgery

Acute liver failure

Snake bites

Transfusion reactions of blood

Chronic DIC:

Malignancies

Leukaemia

Obstetric:

Retained products of conception (eg - dead fetus, post miscarriage).

Vascular:

Rheumatoid arthritis

Inflammatory:

Ulcerative colitis,
Crohn's disease (inflammatory conditions affecting the bowels).

Progression

Disseminated intravascular coagulation begins with over-activation of your body's coagulation system and excessive clotting. The excessive clotting is usually stimulated by a substance that enters the blood, with possible causes as listed above. As the clotting factors and platelets are consumed, there are less clotting factors available to be used at real sites of bleeding and excessive bleeding occurs. The results of this process (ie. abnormal small clots (microthrombi) and/or bleeding) are found in many organs and tissues. Significant changes may occur in some of your body's organs such as the kidney, lungs, brain, adrenals or placenta.

Page 1 2 3