Disseminated Intravascular Coagulation (DIC) Score

The scoring method explained

This is a stratifying tool for risk of disseminated intravascular coagulation that is addressed to patients with a thrombosis associated underlying disorder.

The score was developed in 2009 by The International Society of Thrombosis and Haemostasis (ISTH) (a study by Levi et al.) and is based on the following definition of DIC: an acquired syndrome characterized by intravascular activation of coagulation, due to various causes.

There are four parameters that are monitored:

Result interpretation

Each of the above four parameters are attributed a numeric value. These are summed to provide the final score that varies between 0 and 8.

A cut off of 5 points is applied with 93% sensitivity and 98% specificity for DIC so there are two groups of results:

■ Scores between 0 and 4 are not consistent with disseminated intravascular coagulation, however, if symptoms persist, the score should be reapplied every 24 hours.

■ Scores between 5 and 8 are consistent with DIC and laboratory determinations should continue to be monitored, along with the daily application of the score.

DIC medical guidelines

Intravascular activation of coagulation occurs as a secondary complication to an underlying disorder, the most common being sepsis and malignancy (especially leukemia). Less common DIC triggers include:

■ Trauma (especially brain trauma, crush syndrome);

■ Severe toxic reactions;

■ Organ failure;

■ Incompatible blood transfusion, transplant reactions;

■ Large aortic aneurysms;

■ Obstetric emergencies (amniotic fluid embolism, abruptio placenta, eclampsia).

The thrombin dependent coagulation mechanism is activated in a profuse way which leads to hemorrhage or to thrombosis in the subacute or chronic form.

DIC presentation is consistent with symptoms of the underlying condition but the patient may also have large bruises or spontaneous bleeding at venepuncture. Other characteristic symptoms include confusion, fever, petechia, purpura, adult respiratory distress syndrome (ARDS) or skin necrosis.

There are three criteria that must be met for DIC diagnosis:

■ An underlying disorder associated with DIC;

■ Clinical findings positive for DIC;

■ Laboratory findings* consistent with DIC (evidence of thrombin and plasmin activation).

*Laboratory tests involve a clotting screening that consists of:

■ Prothrombin time (PT);

■ Activated partial thromboplastin time (aPTT);

■ Platelet counts;

■ Fibrinogen level.

The above can be associated with a D-dimer test which is the most specific investigation. Fibrin degradation products test (FDPs) is also used, but has less specificity as it appears in other conditions, such as deep venous thrombosis (DVT).

The D-dimer test is the most specific investigation for DIC while Fibrin degradation products (FDPs) is less specific and appears in other conditions as well, i.e. deep vein thrombosis (DVT).

Prognosis depends on the outcome of the primary condition and on how extensive is the intravascular thrombosis. In serious complications, mortality rates are between 10 and 50% (the latter being recorded in patients with sepsis).

Original source

Levi M, Toh CH, Thachil J, Watson HG. Guidelines for the diagnosis and management of disseminated intravascular coagulation. British Committee for Standards in Haematology. Br J Haematol. 2009; 145(1):24-33.

Other references

1. Voves C, Wuillemin WA, Zeerleder S. International Society on Thrombosis and Haemostasis score for overt disseminated intravascular coagulation predicts organ dysfunction and fatality in sepsis patients. Blood Coagul Fibrinolysis. 2006; 17(6):445-51.

2. Kaneko T, Wada H. Diagnostic criteria and laboratory tests for disseminated intravascular coagulation. J Clin Exp Hematop. 2011; 51(2):67-76.