Consumption Coagulopathy Workup

Updated: Aug 24, 2017
  • Author: Alexander Gozman, MD; Chief Editor: Robert J Arceci, MD, PhD  more...
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Workup

Laboratory Studies

Screening

No single test or combination of tests is adequate to diagnose disseminated intravascular coagulation (DIC). [15] Perform screening tests in all patients, such as platelet count, prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin time, and fibrin degradation products or soluble fibrin monomers. Additional tests that may be useful in aiding in the diagnosis include antithrombin III levels, protein C, D-dimer, fibrinogen, measurements of specific coagulation factors such as factor V and VIII, and plasminogen activator inhibitor type I (PAI-1). Clinical judgment in conjunction with these tests provide a means of working towards a diagnosis of DIC, although no single test results alone are confirmatory. [16]

Thrombocytopenia is an almost universal finding, and the CBC count with smear review may reveal findings suggestive of DIC, such as increased platelet size, schistocytes (see the image below), and helmet cells.

Peripheral blood of a child with disseminated intr Peripheral blood of a child with disseminated intravascular coagulation demonstrates thrombocytopenia and many schistocytes (Wright stain, original magnification X 1000).

The PT and the aPTT are usually prolonged on screening tests but may be normal in an individual in the early phase of DIC ("nonovert DIC").

Fibrin or fibrinogen degradation products and D-dimers are usually elevated due to the rapid generation of fibrin and breakdown of cross-linked fibrin polymers. Although sensitive, these tests are not specific.

Fibrinogen levels are often decreased, as is antithrombin III.

The International Society on Thrombosis and Hemostasis (ISTH) DIC scoring system can help in diagnosis. [17] In the presence of an underlying cause, key tests are performed, and the results are scored as shown in the Table below. A total score of 5 or greater is diagnostic of DIC.

Table. DIC Scoring System (Open Table in a new window)

Measure

Score

0

1

2

3

Platelet count

>100 X 109/L

< 100 X 109/L

< 50 X 109/L

NA

PT prolongation, s

0-3

3-6

6

NA

Fibrinogen level (mg/dL)

>100

< 100

NA

NA

Fibrin split products

NA

NA

+

+++

The most important prognostic factor is the ability to correct the underlying cause and arrest the ongoing derangement of the coagulation system.

A similar scoring system proposed by the Japanese Ministry of Health and Welfare (JMHW) in 1979 used more specific criteria. They numerically categorized the extent of fibrin degradation product, included underlying disease and clinical symptoms as part of the overall scoring system; whereas underlying disease is an essential component in the ISTH system. [11] The ISTH system is useful for predicting overt DIC.

The ISTH DIC scoring system does not precisely define the extent of the increase in fibrin split products or which marker is being measured. Specifying these fibrin products as either D-dimers or soluble fibrin monomers and clearly defining numerical parameters of these products within the scoring system makes the score a more powerful prognostic indicator. [18, 19]

In a retrospective study evaluating prognostic factors influencing mortality in pediatric patients with DIC, multiorgan dysfunction syndrome, acute respiratory distress syndrome, and cardiovascular and respiratory system dysfunction were associated with increased mortality. [10]

A new scoring system used in the pediatric ICU at Texas Children's Hospital used sequential measurement of the same laboratory values along with the clinical condition of the patient to determine if overt DIC is present. This scoring system proved to be more sensitive than ISTH system. [20]

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Other Tests

Because DIC is not the primary disease but a manifestation of underlying illness, diagnosing the initiating disorder is crucial.

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