Info
thrombotic thrombocytopenic purpura
- Pathophys:
↓↓ ADAMTS13 protease activity (hereditary [ Upshaw Schulman Syn.] or autoAb) → vWF multimers persist on endothelial surface → plt adhesion/aggregation → thrombosis
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Clinical: pentad of thrombotic thrombocytopenic purpura (all 5 in only ~5%) = ↓ plts + MAHA (100%) ± Δ MS (65%) ± renal failure (50%, late feature) ± fever (25%)
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PLASMIC score to discriminate TTP from other TMAs (Lancet Haematol. 2017;4:157)
Rx
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urgent plasma exchange ± glucocorticoids;
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FFP if delay to plasma exchange,
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caplacizumab (NEJM 2019;380:335),
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rituximab for 2° prevention (Blood Adv. 2017;1:1159),
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plt transfusions contraindic. → ↑ microvascular thromb (J Thromb Haemost. 2020;18:2496)