Which laboratory test is decreased during a DIC event?

Which laboratory test is decreased during a DIC event?

• A. Fibrinogen
• B. PT
• C. aPTT
• D. Antithrombin

Answer: (A)

In DIC, clotting factors and platelets are consumed as microthrombi form throughout the circulation, creating a consumption coagulopathy. Fibrinogen is one of the factors used up to make fibrin, so its level drops during an active DIC event. That’s why fibrinogen is decreased. In contrast, the time-based clotting tests (prothrombin time and aPTT) are typically prolonged because the clotting factors are depleted, not reduced in activity to a lower level. Antithrombin can also be reduced due to consumption, but the hallmark decrease you’d expect to see in this scenario is fibrinogen.

In DIC, clotting factors and platelets are consumed as microthrombi form throughout the circulation, creating a consumption coagulopathy. Fibrinogen is one of the factors used up to make fibrin, so its level drops during an active DIC event. That’s why fibrinogen is decreased. In contrast, the time-based clotting tests (prothrombin time and aPTT) are typically prolonged because the clotting factors are depleted, not reduced in activity to a lower level. Antithrombin can also be reduced due to consumption, but the hallmark decrease you’d expect to see in this scenario is fibrinogen.