Difference between revisions of "Thrombotic thrombocytopenic purpura"

(edit)
(edit)
Line 4: Line 4:
 
***Leads to platelet aggregation/thrombocytopenia and hemolysis of RBCs
 
***Leads to platelet aggregation/thrombocytopenia and hemolysis of RBCs
 
*Similar to but different from [[HUS]] (which is more common in peds)
 
*Similar to but different from [[HUS]] (which is more common in peds)
*[[Microangiopathic hemolytic anemia]] + low plts is TTP until proven otherwise
+
*[[Microangiopathic Hemolytic Anemia (MAHA)]] + low plts is TTP until proven otherwise
 
*Can occur as a result of [[Plavix]] (clopidogrel) use (usually within first 2 wk of starting)
 
*Can occur as a result of [[Plavix]] (clopidogrel) use (usually within first 2 wk of starting)
  
Line 16: Line 16:
 
==Clinical Features==
 
==Clinical Features==
 
*Pentad
 
*Pentad
#[[Microangiopathic hemolytic anemia (MAHA)]]
+
#[[Microangiopathic Hemolytic Anemia (MAHA)]]
 
#Thrombocytopenia
 
#Thrombocytopenia
 
#Fever
 
#Fever
Line 26: Line 26:
  
 
==DDX==
 
==DDX==
*Other microangiopathic hemolytic anemias (eg, [[HUS]], [[DIC]], [[malignant hypertension]])
+
*Other MAHAs (eg, [[HUS]], [[DIC]], [[malignant hypertension]])
 
*[[ITP]]
 
*[[ITP]]
 
*[[Sepsis]]
 
*[[Sepsis]]
Line 61: Line 61:
  
 
==See Also==
 
==See Also==
*[[Microangiopathic hemolytic anemia]], [[HUS]], [[DIC]]
+
*[[Microangiopathic Hemolytic Anemia (MAHA)]], [[HUS]], [[DIC]]
 
*[[HELLP]], [[SLE]], [[antiphospholipid syndrome]]
 
*[[HELLP]], [[SLE]], [[antiphospholipid syndrome]]
 
*[[ITP]]
 
*[[ITP]]

Revision as of 21:59, 29 November 2013

Background

  • Pathophysiology
    • Insufficient ADAMTS-13 activity allows vWF multimers to accumulate in microcirculation
      • Leads to platelet aggregation/thrombocytopenia and hemolysis of RBCs
  • Similar to but different from HUS (which is more common in peds)
  • Microangiopathic Hemolytic Anemia (MAHA) + low plts is TTP until proven otherwise
  • Can occur as a result of Plavix (clopidogrel) use (usually within first 2 wk of starting)

Risk Factors

  • Congenitally deficient ADAMTS-13 activity and:
  1. Pregnancy
  2. Infection
  3. Inflammation
  4. Medication use (quinolones, ticlopidine, clopidogrel)

Clinical Features

  • Pentad
  1. Microangiopathic Hemolytic Anemia (MAHA)
  2. Thrombocytopenia
  3. Fever
  4. Renal pathology
  5. CNS abnormalities (seizure, AMS, CVA, coma)
  • TTP pentad mnemonic = FAT RN
    • Fever, Anemia, Thrombocytopenia, Renal, Neuro sx

DDX

Work-Up

  • CBC with peripheral smear (anemia, schistocytes, thrombocytopenia)
  • LDH (elevated)
  • Haptoglobin (decreased)
  • Reticulocyte count (appropriate)
  • UA (hemoglobinuria)
  • Creatinine (possibly elevated)
  • LFTs (increased bilirubin)
  • PT/PTT/INR (normal; differentiates from DIC)
  • Urine pregnancy (significant association between pregnancy and TTP)

Treatment

  • Plasma exchange (plasmapheresis)
    • Replaces defective or insufficient ADAMTS-13 and clears vWF multimers
  • Transfusion
    • Indicated if plasma exchange cannot be performed immediately
    • FFP
    • Platelet (only for life-threatening bleeding or intracranial hemorrhage)
      • Platelet infusion may lead to acutely worsened thrombosis, renal failure, and death
  • Splenectomy - 2nd line therapy

Disposition

  • Admit for plasma exchange

See Also

Source

  • Tintinalli
  • Harwood Nuss