Thrombotic Thrombocytopenic Purpura — A Clotting Emergency

Recognition

TTP should be suspected in any patient with thrombocytopenia and haemolysis, especially with neurological or renal symptoms, fever or abdominal pain. The peripheral smear shows schistocytes, and markers of haemolysis are elevated. ADAMTS13 testing supports diagnosis but treatment must not wait for the result.

• Thrombocytopenia with microangiopathic haemolysis
• Schistocytes on peripheral smear
• Elevated LDH, low haptoglobin and raised bilirubin
• Neurological, renal, cardiac or abdominal involvement
• Send ADAMTS13 but do not delay treatment

Emergency treatment

Urgent plasma exchange is the cornerstone of treatment, together with corticosteroids and supportive care. Caplacizumab may be used in selected settings. Platelet transfusion is generally avoided unless there is life-threatening bleeding. Relapse and long-term follow-up require ADAMTS13 monitoring.

• Urgent plasma exchange
• Corticosteroids
• Caplacizumab in selected patients
• Avoid platelet transfusion unless severe bleeding
• Monitor ADAMTS13 for relapse

Guidelines referenced:

• International guideline on the diagnosis and management of TTP
• British Society for Haematology TTP guidelines
• ISTH guidance on thrombotic microangiopathies