This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

Go to /pro/cpd-dashboard page

This page is worth 0.05 CPD credits. CPD dashboard

Go to /account/subscription-details page

This page is worth 0.05 CPD credits. Upgrade to Pro

Thrombotic thrombocytopenia purpura

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

Thrombotic thrombocytopenic purpura is an uncommon syndrome characterised by:

  • fever
  • microangiopathic haemolytic anaemia
  • thrombocytopenia
  • neurologic and renal abnormalities

Thrombotic thrombocytopenic purpura (TTP), a potentially fatal clinical syndrome, is primarily caused by autoantibodies against the von Willebrand factor (VWF)-cleaving metalloprotease ADAMTS13 (2)

  • in general, severe deficiency of plasma ADAMTS13 activity (<10 IU/dL) with or without detectable inhibitory autoantibodies against ADAMTS13 supports the diagnosis of TTP if a patient presents with thrombocytopenia and microangiopathic hemolytic anemia (i.e. schistocytes, elevated serum lactate dehydrogenase, decreased hemoglobin and haptoglobin) without other known etiologies that cause thrombotic microangiopathy (TMA)

TTP often follows infection or in women, oral contraception or pregnancy

TTP is a critical medical condition requiring immediate transfer for treatment. (1)

  • 50% of patients require intensive care admission and without treatment, the mortality in acute TTP is >90%.

TTP results from a deficiency of the enzyme ADAMTS 13, required for Von Willebrand factor (vWF) cleavage

  • severely reduced enzyme levels are caused either by a genetic abnormality or through their destruction by antibodies
  • deficiency of the ADAMTS13 enzyme results in insufficient processing of the large vWF clotting factor which unravels during passage through the microcirculation leading to platelet aggregation and multi-organ microvascular thrombosis involving neurological, cardiac, gastro-intestinal and renal disease
    • occlusion of small vessels also causes a fragmentation haemolysis (microangiopathic haemolytic anaemia) and platelet consumption resulting in thrombocytopenia.

Young adults from 20 to 50 years are predominantly affected, with a slight female preponderance

Prompt differentiation of TTP from other causes of TMA is crucial for the initiation of an appropriate therapy to reduce morbidity and mortality.

Management

  • plasma infusion is often sufficient for prophylaxis or treatment of hereditary TTP due to ADAMTS13 mutations
  • daily therapeutic plasma exchange is the initial treatment of choice for acquired TTP with autoantibodies
  • immunomodulatory therapies, including corticosteroids, rituximab, vincristine, cyclosporine, cyclophosphamide, and splenectomy, etc. should be considered to eliminate autoantibodies for sustained remission (2)

Notes

  • normal to moderately reduced plasma ADAMTS13 activity (>20 IU/dL) in a similar clinical context supports an alternative diagnosis such as atypical hemolytic uremic syndrome (aHUS) or other types of TMA

Reference:


Create an account to add page annotations

Annotations allow you to add information to this page that would be handy to have on hand during a consultation. E.g. a website or number. This information will always show when you visit this page.

The content herein is provided for informational purposes and does not replace the need to apply professional clinical judgement when diagnosing or treating any medical condition. A licensed medical practitioner should be consulted for diagnosis and treatment of any and all medical conditions.

Connect

Copyright 2024 Oxbridge Solutions Limited, a subsidiary of OmniaMed Communications Limited. All rights reserved. Any distribution or duplication of the information contained herein is strictly prohibited. Oxbridge Solutions receives funding from advertising but maintains editorial independence.