Difference between revisions of "Disseminated intravascular coagulation"

(Causes)
(Clinical Features)
Line 22: Line 22:
  
 
==Clinical Features==
 
==Clinical Features==
*In given pt either bleeding or thrombosis will predominate
+
''In given pt either bleeding or thrombosis will predominate (Bleeding is more common ~65%)''
**Bleeding is more common (65% of pts)
+
*Shock (15%)
***Ranges from petechiae/ecchymosis to life-threatening GI/CNS/pulm bleeding
+
*[[Acute renal failure]] (25-40%)
***Shock occurs in 15%
+
*Hepatic dysfunction (19%)
**Renal failure (25-40%)
+
*Respiratory dysfunction (16%)
**Hepatic dysfunction (19%)
+
*[[Thromboembolism]] (7%)
**Respiratory dysfunction (16%)
+
*CNS involvement (2%)
**Thromboembolism (7%)
+
*Purpura fulminans (widespread arterial and venous thromboses)
**CNS involvement (2%)
+
**Associated with significant bacteremia
**Purpura fulminans (widespread arterial and venous thromboses)
 
***Associated w/ significant bacteremia
 
  
 
==Differential Diagnosis==
 
==Differential Diagnosis==

Revision as of 05:20, 6 June 2015

Background

  • Widespread and inappropriate activation of the coagulation and fibrinolytic systems
    • Exposure of blood to procoagulants such as tissue factor and cancer procoagulant
    • Formation of fibrin within the circulation
    • Fibrinolysis
    • Depletion of clotting factors
    • End-organ damage
  • Chronic DIC occurs when hepatic/bone marrow production balances coag factor consumption

Causes

Clinical Features

In given pt either bleeding or thrombosis will predominate (Bleeding is more common ~65%)

  • Shock (15%)
  • Acute renal failure (25-40%)
  • Hepatic dysfunction (19%)
  • Respiratory dysfunction (16%)
  • Thromboembolism (7%)
  • CNS involvement (2%)
  • Purpura fulminans (widespread arterial and venous thromboses)
    • Associated with significant bacteremia

Differential Diagnosis

  • TTP-HUS
    • Pts usually have little or no prolongation of PT or PTT
  • Severe liver disease
    • Also a/w prolonged PT/PTT, thrombocytopenia, incr D-dimer, incr FDPs
      • However, D-dimer is usually only mildly elevated
  • Heparin-induced thrombocytopenia

Thrombocytopenia

Decreased production

Increased platelet destruction or use

Drug Induced

Comparison by Etiology

ITP TTP HUS HIT DIC
↓ PLT Yes Yes Yes Yes Yes
↑PT/INR No No No +/- Yes
MAHA No Yes Yes No Yes
↓ Fibrinogen No No No No Yes
Ok to give PLT Yes No No No Yes

Diagnosis

  • Acute DIC
    • Platlets
      • Low (or dropping)
      • Sn, not Sp
    • PT
      • Prolonged
    • Fibrinogen
      • Low
      • <100 correlates w/ severe DIC
      • May be normal (acute phase reactant)
    • PTT
      • Prolonged
    • FDP
      • Elevated
    • D-dimer
      • Elevated
      • Sn but not Sp: may also see in pts w/ chronic liver or renal disease
    • RBCs
      • Fragmented (not specific)
  • Chronic DIC
    • FDP: Elevated
    • D-dimer: Elevated
    • Platelet: Variable
    • Fibrinogen: Normal-elevated
    • PT: Normal
    • PTT: Normal
    • RBCs
      • Fragmented

Treatment

  • Treat underlying illness
  • Replacement tx
    • Only indicated in pts w/ documented DIC + bleeding or impending procedure
      • Fibrinogen
        • Consider repletion w/ cryoprecipitate to raise level to 100-150
      • Platelets
        • Consider repletion if <50K w/ bleeding or <20K without bleeding
      • FFP
      • Vitamin K
      • Folate
    • Heparin
      • Consider only in pts w/ thromboembolic predominant symptoms from chronic DIC

See Also

References