A Practical Guide to Haemostasis

The Modified ISTH DIC Scoring Algorithm


The ISTH Overt DIC Scoring algorithm was developed by the SSC committee on DIC and published in 2001. This algorithm is only appropriate for use in patients with an underlying disorder that is known to be associated with DIC.  Such disorders include: sepsis, malignancy, trauma, obstetric complications, various vascular malformations, severe immunological reactions, heat stroke and following cardio-pulmonary resuscitation.

The Modified ISTH DIC score is very similar but removes Fibrinogen from the algorithm - see below:

The Modified ISTH DIC Score:

Select Criteria:

Platelet Count
>100 x 109/L 0 Points
>50 - <100 x 109/L 1 Point
<50 x 109/L 2 Points
Increase in Fibrin-related Markers [D Dimers]
No change 0 Points
Moderate rise 2 Points
Strong rise 3 Points
Prothrombin Time [PT] Prolongation
3 s or less 0 Points
>3 s but <6 s 1 Point
>6 s 2 Points


[Max score 6 points]

Interpretation of Score
< 5 Suggestive of non-overt/low grade DIC. 
Repeat in 1-2 days.
≥ 5 Laboratory evidence consistent with overt DIC. 
Repeat score daily

Click HERE to Reset


A Clinical and Laboratory scoring system for non-overt DIC has been developed - see References Toh et al 2005.

See also the ISTH 'Sepsis-Induced Coagulopathy [SIC] algorithm.