Transfusion medicine
Transfusion side effects
Post transfusion purpura (PTP)

Author: Huy Phu Pham, M.D. (see Authors page)

Revised: 15 November 2017, last major update September 2011

Copyright: (c) 2002-2017, PathologyOutlines.com, Inc.

PubMed Search: Posttransfusion purpura [title]

Cite this page: Pham, H.P. Post transfusion purpura (PTP). PathologyOutlines.com website. http://pathologyoutlines.com/topic/transfusionmedposttransfusionpurpura.html. Accessed November 18th, 2017.
Definition / general
  • Rare complication of transfusion (0.3 of 100,000 components transfused in the UK)
  • Typically occurs 2 - 14 days after transfusion of pRBC, platelets or plasma, resulting in platelet count < 10,000/mcL
  • Most often implicated in transfusion of pRBCs
  • Often seen in multiparous women with prior sensitization from pregancies
Pathophysiology
  • Immune thrombocytopenia from antiplatelet alloantibodies (most commonly anti-HPA-1a)
  • Occurs in both transfused and autologous platelets; mechanism of destroying autologous platelets is unknown
Clinical manifestation
  • Unexplained bruising or bleeding 2 - 14 days after transfusion
  • Mortality of 10% due to bleeding
  • About 30% have major bleeding
  • If disease is limited, platelet count will recover within 21 days
Diagnosis
  • Confirmed by detection of platelet specific alloantibodies
  • Differential diagnosis: ITP, drug induced, DIC / TTP, heparin induced thrombocytopenia (Thromb Res 2000;100:115)
Case reports
Treatment
  • IV immunoglobulin (0.4 g/kg/day for 5 - 8 days)
  • Possibly plasmapheresis or corticosteroids
  • Platelet transfusions usually NOT recommended