From the Guidelines
To work up Disseminated Intravascular Coagulation (DIC), order a comprehensive panel including complete blood count with platelet count, prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen level, D-dimer, and fibrin degradation products (FDPs) as recommended by the most recent guidelines 1. These tests should be ordered simultaneously to establish a baseline and may need to be repeated every 6-8 hours to monitor progression. Additional helpful tests include:
- Blood smear examination for schistocytes
- Thrombin time
- Specific factor assays (particularly factors V and VIII) Liver function tests and renal function tests are important to assess organ damage. The diagnosis of DIC relies on demonstrating both consumption of coagulation factors (prolonged PT/aPTT, decreased fibrinogen, thrombocytopenia) and increased fibrinolysis (elevated D-dimer and FDPs) 1. This combination reflects the pathophysiology of DIC, which involves inappropriate, widespread activation of coagulation leading to simultaneous thrombosis and hemorrhage. The International Society on Thrombosis and Hemostasis DIC scoring system uses these laboratory values to calculate a score that helps confirm the diagnosis and assess severity 1. It is also important to consider the sepsis-induced coagulopathy (SIC) scoring system for early detection of DIC in sepsis patients, as it can lead to overt DIC with disease progression 1. Regular monitoring of patients at risk of developing cancer-related DIC is also crucial, including regular blood count and clotting screen, including fibrinogen and D-dimer measurements 1. However, the most recent and highest quality study 1 prioritizes the use of the comprehensive panel and the ISTH DIC scoring system for the diagnosis and management of DIC.
From the Research
Laboratory Tests for Disseminated Intravascular Coagulation (DIC)
To work up DIC, the following laboratory tests are considered:
- Platelet count: A platelet count of <50 x 10(9)/l is considered a threshold for transfusion in patients with DIC and bleeding or at high risk of bleeding 2
- Prothrombin time (PT) and activated partial thromboplastin time (aPTT): Prolonged PT and aPTT may indicate the need for administration of fresh frozen plasma (FFP) in bleeding patients with DIC 2
- Fibrinogen level: Severe hypofibrinogenemia (<1 g/l) may be treated with fibrinogen concentrate or cryoprecipitate 2
- International Society for Thrombosis and Haemostasis (ISTH) DIC scoring system: This system provides an objective measurement of DIC and correlates with key clinical observations and outcomes 2
Additional Considerations
- Repeating laboratory tests is important to monitor the dynamically changing scenario based on laboratory results and clinical observations 2
- Treatment of the underlying condition is the cornerstone of DIC management 2, 3
- Transfusion of platelets or plasma components should not be based solely on laboratory results, but rather on clinical judgment and the presence of bleeding or high risk of bleeding 2