Difference between revisions of "Thrombotic thrombocytopenic purpura"

Line 7: Line 7:
  
 
===Risk Factors===
 
===Risk Factors===
#Congenitally deficient ADAMTS-13 activity and:
+
*Congenitally deficient ADAMTS-13 activity and:
##Pregnancy
+
#Pregnancy
##Infection
+
#Infection
##Inflammation
+
#Inflammation
##Medication use
+
#Medication use (quinolones, ticlopidine, clopidogrel)
###Quinolones, ticlopidine, clopidogrel
 
  
 
==Clinical Features==
 
==Clinical Features==
#Pentad
+
*Pentad
##CNS abnormalities
+
#Microangiopathic hemolytic anemia
###Seizure, CVA, coma
+
#Thrombocytopenia
##Renal pathology
+
#Fever
##Microangiopathic hemolytic anemia
+
#Renal pathology
##Thrombocytopenia
+
#CNS abnormalities (seizure, AMS, CVA, coma)
##Fever
 
  
#TTP pentad mnemonic = FAT RN
+
*TTP pentad mnemonic = FAT RN
##Fever, Anemia, Thrombocytopenia, Renal, Neuro sx
+
**Fever, Anemia, Thrombocytopenia, Renal, Neuro sx
  
 
==DDX==
 
==DDX==
#Other microangiopathic hemolytic anemias (HUS, DIC, malignant HTN)
+
*Other microangiopathic hemolytic anemias (HUS, DIC, malignant HTN)
#ITP
+
*ITP
#Sepsis
+
*Sepsis
#SLE
+
*SLE
#HELLP syndrome
+
*HELLP syndrome
##Difficult to distinguish
+
**Difficult to distinguish
##Anemia, plt count, and LDH tend to be more severe in TTP; LFTs more severe in HELLP
+
**Anemia, plt count, and LDH tend to be more severe in TTP; LFTs more severe in HELLP
  
 
== Work-Up ==
 
== Work-Up ==
  
#CBC with peripheral smear
+
*CBC with peripheral smear (anemia, '''schistocytes''', thrombocytopenia)
##Anemia, '''schistocytes''', thrombocytopenia  
+
*LDH (elevated)
#LDH  
+
*Haptoglobin (decreased)
#Haptoglobin  
+
*Reticulocyte count (appropriate)
#UA  
+
*UA (hemoglobinuria)
##Hemoglobinuria
+
*Creatinine (possibly elevated)
##Creatinine  
+
*LFTs (increased bilirubin)
#LFT
+
*PT/PTT/INR (normal; differentiates from DIC)  
##Increased bilirubin  
+
*Urine pregnancy (significant association between pregnancy and TTP)
#PT/PTT/INR  
 
##Normal (differentiates from DIC)  
 
#Urine pregnancy  
 
##Significant association between pregnancy and TTP
 
  
 
== Treatment ==
 
== Treatment ==
  
#Plasma exchange (plasmapheresis)  
+
*Plasma exchange (plasmapheresis)  
##Replaces defective or insufficient ADAMTS-13 and clears vWF multimers  
+
**Replaces defective or insufficient ADAMTS-13 and clears vWF multimers  
#Transfusion  
+
*Transfusion  
##Indicated if plasma exchange cannot be performed immediately  
+
**Indicated if plasma exchange cannot be performed immediately  
##FFP  
+
**FFP  
##Platelet (only for life-threatening bleeding or intracranial hemorrhage)  
+
**Platelet (only for life-threatening bleeding or intracranial hemorrhage)  
###Platelet infusion may lead to acutely worsened thrombosis, renal failure, and death
+
***Platelet infusion may lead to acutely worsened thrombosis, renal failure, and death
#Splenectomy - 2nd line therapy
+
*Splenectomy - 2nd line therapy
  
 
==Disposition==
 
==Disposition==

Revision as of 17:46, 4 October 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 + low plts is TTP until proven otherwise

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
  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

  • Other microangiopathic hemolytic anemias (HUS, DIC, malignant HTN)
  • ITP
  • Sepsis
  • SLE
  • HELLP syndrome
    • Difficult to distinguish
    • Anemia, plt count, and LDH tend to be more severe in TTP; LFTs more severe in HELLP

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

Source

  • Tintinalli
  • Harwood Nuss