Disseminated Intravascular Coagulation (ISTH 2025)

Algorithm Steps

1. ▶

   Start

   Suspected DIC

   Patient with underlying condition and signs of coagulopathy

   1. ◆

      Decision

      Underlying Disorder Present?

      DIC requires an inciting cause

      • Sepsis/severe infection
      • Trauma/surgery
      • Malignancy (especially APL)
      • Obstetric complications
      • Vascular abnormalities
      • Severe toxic/immunologic reactions
      1. ✓

         Outcome

         DIC Unlikely

         Consider alternative diagnoses

         • TTP/HUS
         • Liver disease
         • Primary fibrinolysis
         • Heparin effect
      2. ●

         Action

         Calculate ISTH DIC Score

         Sum points from 4 parameters

         • Platelet count: >100=0, 50-100=1, <50=2
         • D-dimer: Normal=0, Moderate↑=2, Strong↑=3
         • Prolonged PT: <3s=0, 3-6s=1, >6s=2
         • Fibrinogen: >1.0g/L=0, <1.0g/L=1
         1. ◆

            Decision

            ISTH DIC Score Result

            Interpret total score

            1. ●

               Action

               Score <5: Non-Overt DIC

               May be early or compensated DIC

               • Repeat scoring daily
               • Treat underlying cause aggressively
               • Monitor for progression
               • Consider prophylactic anticoagulation if indicated
               1. ●

                  Action

                  Serial Monitoring

                  Repeat DIC score every 12-24 hours

                  • CBC with platelets
                  • PT/PTT
                  • Fibrinogen
                  • D-dimer
                  • Clinical reassessment
                  1. ✓

                     Outcome

                     DIC Resolving

                     Score decreasing, clinical improvement

                  2. ✓

                     Outcome

                     DIC Ongoing

                     Reassess treatment, consider specialist consult

            2. ⚠

               Warning

               Score ≥5: Overt DIC

               Confirmed DIC - initiate treatment

               1. ●

                  Action

                  Treat Underlying Cause

                  Cornerstone of DIC management

                  • Antibiotics for sepsis
                  • Surgical debridement if needed
                  • Delivery for obstetric DIC
                  • Chemotherapy for APL (with ATRA)
                  • Supportive care
                  1. ◆

                     Decision

                     Predominant Phenotype?

                     Bleeding vs thrombotic manifestations

                     1. ●

                        Action

                        Bleeding Predominant

                        Replacement therapy

                        • Platelets if <20 or <50 with bleeding
                        • FFP if PT/PTT prolonged with bleeding
                        • Cryoprecipitate if fibrinogen <1.5 g/L
                        • Tranexamic acid may be considered
                        • Avoid heparin typically
                     2. ●

                        Action

                        Thrombosis Predominant

                        Consider anticoagulation

                        • UFH or LMWH if no contraindication
                        • Lower prophylactic doses typically
                        • Balance bleeding risk
                        • Protein C concentrate in severe sepsis (purpura fulminans)