Difference between revisions of "Thrombotic thrombocytopenic purpura"

(Source)
Line 1: Line 1:
 
==Background==
 
==Background==
*Pathophysiology
+
===Pathophysiology===
**Insufficient ADAMTS-13 activity allows vWF multimers to accumulate in microcirculation
+
*Insufficient ADAMTS-13 activity allows vWF multimers to accumulate in microcirculation which leads to platelet aggregation/thrombocytopenia and hemolysis of RBCsPlatelet clots are transient, but the symptoms especially neuro, can be in flux.
***Leads to platelet aggregation/thrombocytopenia and hemolysis of RBCs
+
 
****Platelet clots are transient, symptoms, especially neuro, can be in flux
+
*Similar clinical symptoms but different pathophysiology than [[HUS]]
*Similar to but different from [[HUS]] (which is more common in peds)
+
**[[HUS]] More common in pediatrics
*[[Microangiopathic Hemolytic Anemia (MAHA)]] + low plts is TTP until proven otherwise
+
*'''[[Microangiopathic Hemolytic Anemia (MAHA)]] + [[thrombocytopenia|low Platelets]] 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, especially within the first 2 weeks
  
 
===Risk Factors===
 
===Risk Factors===
*Congenitally deficient ADAMTS-13 activity and:
+
;Congenitally deficient ADAMTS-13 activity AND:
 
#Pregnancy
 
#Pregnancy
 
#Infection
 
#Infection
Line 15: Line 15:
 
#Medication use (quinolones, ticlopidine, clopidogrel)
 
#Medication use (quinolones, ticlopidine, clopidogrel)
  
==Clinical Features==
+
==Clinical Features<ref>George J: Clinical practice. Thrombotic thrombocytopenic purpura. N Engl J Med 2006; 354:1927</ref>==
*Pentad (rarely all present)
+
===Pentad (rarely all present)===
#[[Microangiopathic Hemolytic Anemia (MAHA)]]
+
#'''[[Microangiopathic Hemolytic Anemia (MAHA)]]'''
#Thrombocytopenia
+
#'''Thrombocytopenia'''
#Fever
+
#'''Fever'''
#Renal pathology
+
#'''Renal pathology'''
#CNS abnormalities (seizure, AMS, CVA, coma)
+
#'''CNS abnormalities (seizure, AMS, CVA, coma)'''
*Neuro symptoms are often transient, may not be present in ED
+
#*Neuro symptoms are often transient, may not be present in ED
  
*TTP pentad mnemonic = FAT RN
+
;TTP pentad mnemonic = '''FAT RN'''
**Fever, Anemia, Thrombocytopenia, Renal, Neuro sx
+
*Fever, Anemia, Thrombocytopenia, Renal, Neuro Symptoms
***All features do not need to be present at the same time
 
  
 +
*''All features DO NOT need to be present at the same time''
 
*Consider diagnosis without the full pentad
 
*Consider diagnosis without the full pentad
**MAHA + Thrombocytopenia + any other feature
 
  
==DDX==
+
==Differential Diagnosis==
 
*Other MAHAs (eg, [[HUS]], [[DIC]], [[malignant hypertension]])
 
*Other MAHAs (eg, [[HUS]], [[DIC]], [[malignant hypertension]])
 
*[[ITP]]
 
*[[ITP]]
Line 37: Line 36:
 
*[[SLE]]
 
*[[SLE]]
 
*[[HELLP]] syndrome
 
*[[HELLP]] syndrome
**Difficult to distinguish
+
*Anemia, platelet 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 (anemia, '''schistocytes''', thrombocytopenia are suggestive findings)
*CBC with peripheral smear (anemia, '''schistocytes''', thrombocytopenia)
 
 
*LDH (elevated)
 
*LDH (elevated)
 
*Haptoglobin (decreased)
 
*Haptoglobin (decreased)
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*Urine pregnancy (significant association between pregnancy and TTP)
 
*Urine pregnancy (significant association between pregnancy and TTP)
  
== Treatment ==
+
== Treatment<ref>George J. How I treat patients with thrombotic thrombocytopenic purpura: 2010. Blood 2010; 116:4060</ref> ==
 +
;All treatments should be performed with a hematology consultation
  
*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 of RBCs''' (only severe bleeding)
**Indicated if plasma exchange cannot be performed immediately  
+
#*Generally only indicated if plasma exchange cannot be performed immediately  
**FFP  
+
#'''FFP Transfusion'''
***Contains ADAMTS-13
+
#*Contains ADAMTS-13
**Platelet (only for life-threatening bleeding or intracranial hemorrhage)
+
#*Should only be initiated if delay in plasmapheresis
***Platelet infusion may lead to acutely worsened thrombosis, renal failure, and death
+
#'''Platelet Transfusion is AVOIDED'''
*Splenectomy - 2nd line therapy
+
#*Only used for life-threatening bleeding or intracranial hemorrhage under guidance from hematologist
 +
#*Platelet infusion may lead to acutely worsened thrombosis, renal failure, and death
 +
#'''Splenectomy''' - 2nd line therapy after stabilization
  
 
==Disposition==
 
==Disposition==
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==Source ==
 
==Source ==
 
<references/>
 
<references/>
*Tintinalli
+
*Hirsh J et al. [Antithrombotic and thrombolytic therapy: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest 2008; 133(Suppl):110S-112S http://journal.publications.chestnet.org/pdfaccess.ashx?ResourceID=2124970&PDFSource=13]
*Harwood Nuss
 
*Rosens
 
 
[[Category:Heme/Onc]]
 
[[Category:Heme/Onc]]

Revision as of 21:29, 5 June 2014

Background

Pathophysiology

  • Insufficient ADAMTS-13 activity allows vWF multimers to accumulate in microcirculation which leads to platelet aggregation/thrombocytopenia and hemolysis of RBCs. Platelet clots are transient, but the symptoms especially neuro, can be in flux.

Risk Factors

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

Clinical Features[1]

Pentad (rarely all present)

  1. Microangiopathic Hemolytic Anemia (MAHA)
  2. Thrombocytopenia
  3. Fever
  4. Renal pathology
  5. CNS abnormalities (seizure, AMS, CVA, coma)
    • Neuro symptoms are often transient, may not be present in ED
TTP pentad mnemonic = FAT RN
  • Fever, Anemia, Thrombocytopenia, Renal, Neuro Symptoms
  • All features DO NOT need to be present at the same time
  • Consider diagnosis without the full pentad

Differential Diagnosis

Work-Up

  • CBC with peripheral smear (anemia, schistocytes, thrombocytopenia are suggestive findings)
  • 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[2]

All treatments should be performed with a hematology consultation
  1. Plasma exchange (plasmapheresis)
    • Replaces defective or insufficient ADAMTS-13 and clears vWF multimers
  2. Transfusion of RBCs (only severe bleeding)
    • Generally only indicated if plasma exchange cannot be performed immediately
  3. FFP Transfusion
    • Contains ADAMTS-13
    • Should only be initiated if delay in plasmapheresis
  4. Platelet Transfusion is AVOIDED
    • Only used for life-threatening bleeding or intracranial hemorrhage under guidance from hematologist
    • Platelet infusion may lead to acutely worsened thrombosis, renal failure, and death
  5. Splenectomy - 2nd line therapy after stabilization

Disposition

  • Admit for plasma exchange

See Also

Source

  1. George J: Clinical practice. Thrombotic thrombocytopenic purpura. N Engl J Med 2006; 354:1927
  2. George J. How I treat patients with thrombotic thrombocytopenic purpura: 2010. Blood 2010; 116:4060