Clark et al reported modified criteria for disseminated intravascular coagulation (DIC) for use in a pregnant or recently pregnant woman. These are based on a modification of the ISTH criteria. The authors are from Baylor College of Medicine in Houston, National Institute of Child Health and Human Development, Columbia University, CDC, Banner Health in Phoenix and the University of Texas Medical Branch in Galveston.
Patient selection: pregnant or formerly pregnant woman with suspected DIC
Differences from ISTH criteria:
(1) fibrin degradation products not included (because of physiologic increase in fibrin breakdown products), resulting in a lower total score
(2) inclusion of INR, with scoring based on percent increase from baseline (the normal INR is 0.8 to 1.2 but an increase would seem to be from baseline).
(3) different cutoffs for plasma fibrinogen (see note)
NOTE: Table 3 reports fibrinogen concentration cutoff of 200 mg/L, or 20 mg/dL. In the text they reference the ISTH cutoff of "100 mg/L". In actuality the ISTH cutoff is 100 mg/dL. A plasma fibrinogen of 20 mg/dL is very low. The text says that fibrinogen is elevated during the third trimester, indicating that 200 mg/dL should be the true cutoff.
NOTE: Table 3 reports the platelet count per mL when it should be per microliter. The breakpoints in Table 3 show "<" and ">" for the platelet count and fibrinogen concentration but not "=".
Parameters:
(1) platelet count per microliter
(2) INR, as ratio to baseline
(3) plasma fibrinogen concentration in mg/dL
|
Parameter
|
Finding
|
Points
|
|
platelet count
|
> 100,000 per µL
|
0
|
|
|
50,000 to 100,000
|
1
|
|
|
< 50,000 per µL
|
2
|
|
INR
|
< 25% increase
|
0
|
|
|
25 to 50% increase
|
1
|
|
|
> 50% increase
|
2
|
|
fibrinogen
|
>= 200 mg/dL
|
0
|
|
|
< 200 mg/dL
|
1
|
total score =
= SUM(points for all 3 parameters)
Interpretation:
• minimum score: 0
• maximum score: 5
• A score >= 3 is compatible with overt DIC.
• A diagnosis of DIC should exclude dilutional coagulopathy or shock- related DIC secondary to massive hemorrhage.
