What patient groups is Thrombotic thrombocytopenic purpura most common?

rare, typically adult females

What are the main clinical features of Thrombotic thrombocytopenic purpura?

• fever
• fluctuating neuro signs (microemboli)
• microangiopathic haemolytic anaemia
• thrombocytopenia
• renal failure

What is the management of Thrombotic thrombocytopenic purpura?

• no antibiotics - may worsen outcome
• plasma exchange is the treatment of choice
• steroids, immunosuppressants
• vincristine

What are the main causes of Thrombotic thrombocytopenic purpura?

• post-infection e.g. urinary, gastrointestinal
• pregnancy
• drugs: ciclosporin, oral contraceptive pill, penicillin, clopidogrel, aciclovir
• tumours
• SLE
• HIV

What is the pathophysiology of Thrombotic thrombocytopenic purpura?

• abnormally large and sticky multimers of von Willebrand's factor cause platelets to clump within vessels
• caused by a deficiency of ADAMTS13 (a metalloprotease enzyme) which breakdowns ('cleaves') large multimers of von Willebrand's factor