Pseudothrombocytopenia in Patients with Scrub Typhus Infection

  • Tanuj Moses Lamech
  • Margaret ChellarajEmail author
  • Ratakonda Penchalaiah
  • Damodaran Dhanasekaran
Short Communication


Pseudothrombocytopenia is an ex vivo EDTA-dependent artefactual thrombocytopenia, that has been described in association with several conditions. When EDTA-blood samples are drawn from patients with pseudothrombocytopenia and analysed by automated cell counters, low platelet counts are obtained (often below 50,000/mm3). However, simultaneous heparinised samples show normal platelet counts, and peripheral smears show no reduction in numbers of platelets. We report a series of 12 patients with scrub typhus infections and pseudothrombocytopenia. An association between these two entities has only recently been appreciated. It appears that pseudothrombocytopenia may sometimes accompany acute scrub typhus infections. The distinction between pseudothrombocytopenia and true thrombocytopenia is of great clinical relevance, as the former is merely a laboratory artefact, and does not require blood product transfusions despite apparently severe reductions in platelet counts. It is therefore important to recognise that apparent thrombocytopenia, especially in patients with an acute febrile illness due to scrub typhus, is not always true thrombocytopenia.


Scrub typhus Pseudothrombocytopenia Orientia Eschar 


Compliance with Ethical Standards

Conflict of interest

The authors declare that there is no conflict of interest.


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Copyright information

© Indian Society of Hematology and Blood Transfusion 2019

Authors and Affiliations

  1. 1.Institute of Internal MedicineMadras Medical CollegeChennaiIndia
  2. 2.Department of HematologyMadras Medical CollegeChennaiIndia

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