Chronic Causes of Disseminated Intravascular Coagulation
Neoplasms (option d) and vascular aneurysms (option b) are the chronic causes of DIC from the listed options, while viral infections, graft rejection, and placental abruption typically cause acute DIC.
Understanding Acute vs. Chronic DIC
The distinction between acute and chronic DIC is critical for identifying the underlying etiology:
Acute DIC Causes (NOT chronic)
Placental abruption (option e) is a classic acute obstetric cause of DIC, associated with sudden release of tissue factor from trophoblastic tissue, maternal decidua, or endothelium, leading to rapid-onset consumptive coagulopathy 1, 2
Viral infections (option a) typically cause acute DIC through sepsis mechanisms, with endotoxin-mediated endothelial dysfunction and systemic inflammation triggering the coagulation cascade 3
Graft rejection (option c) would present as an acute inflammatory process with tissue damage, not a chronic consumptive coagulopathy
Chronic DIC Causes (CORRECT answers)
Neoplasms (option d) represent a major chronic cause of DIC:
Cancer-associated DIC can present in three distinct forms: procoagulant, hyperfibrinolytic, and subclinical (chronic) 4, 3
Pancreatic cancers and adenocarcinomas pose particularly high risks for chronic DIC 4, 3
The subclinical form manifests as persistent laboratory abnormalities (thrombocytopenia, hypofibrinogenemia, elevated D-dimer) without obvious clinical symptoms, remaining long-standing due to continuous thrombin generation 4
Metastatic prostate cancer and hematologic malignancies can cause chronic DIC, with approximately 15% of acute leukemia patients developing overt DIC 5
Vascular aneurysms (option b) cause chronic DIC through:
- Continuous low-grade activation of coagulation within the aneurysm sac
- Chronic endothelial injury and blood stasis leading to ongoing consumption of platelets and coagulation factors 3
Key Clinical Distinction
A mandatory condition for diagnosing DIC is the presence of an underlying disorder known to be associated with DIC 4, 6. The temporal pattern (acute vs. chronic) helps identify the underlying cause:
Acute DIC: Sepsis, trauma, obstetric emergencies (placental abruption, amniotic fluid embolism), acute liver failure 3, 7, 1
Chronic/Subclinical DIC: Malignancies, vascular abnormalities (aneurysms), retained dead fetus 4, 3
Clinical Pitfall to Avoid
Do not confuse chronic liver disease (cirrhosis) with chronic DIC—while cirrhotic patients may have laboratory values resembling DIC, this represents "rebalanced hemostasis" rather than true consumptive coagulopathy unless a secondary trigger (infection, bleeding, shock) is present 4