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Pseudothrombocytopenia in Patients with Scrub Typhus Infection

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

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.

Keywords

Scrub typhus Pseudothrombocytopenia Orientia Eschar 

Notes

Compliance with Ethical Standards

Conflict of interest

The authors declare that there is no conflict of interest.

References

  1. 1.
    Kasper DL, Fauci AS, Hauser SL, Longo DL, Jameson JL, Loscalzo J (2015) Harrison’s principles of internal medicine, 19th edn. McGraw-Hill Education, New York, p 725Google Scholar
  2. 2.
    Sinha SK, Mandal PK, Mallick J (2011) Pseudothrombocytopenia: a caveat. J Indian Med Assoc 109(7):476–478Google Scholar
  3. 3.
    Sahin C, Kirli I, Sozen H, Canbek TD (2014) EDTA-induced pseudothrombocytopenia in association with bladder cancer. BMJ Case Rep 2014:bcr2014205130CrossRefPubMedCentralGoogle Scholar
  4. 4.
    Holmes MB, Kabbani S, Watkins MW, Battle RW, Schneider DJ (2000) Images in cardiovascular medicine: abciximab-associated pseudothrombocytopenia. Circulation 101:938–939CrossRefGoogle Scholar
  5. 5.
    Choe WH, Cho YU, Chae JD, Kim SH (2013) Pseudothrombocytopenia or platelet clumping as a possible cause of low platelet count in patients with viral infection: a case series from single institution on hepatitis A virus infection. Int J Lab Hematol 35(1):70–76CrossRefGoogle Scholar
  6. 6.
    Mohan BP, Sheeja S, Prabhalekshmy KK (2016) EDTA dependent pseudothrombocytopenia in a patient with scrub typhus: a case report. BMH Med J 3(1):15–18Google Scholar
  7. 7.
    Rajajee S, Subbiah E, Krishnamurthy N, Paranjothi S, Lohiya N (2018) Pseudothrombocytopenia and usefulness of platelet aggregates in peripheral smear in the diagnosis of scrub typhus. Indian J Pediatr.  https://doi.org/10.1007/s12098-018-2712-2 Google Scholar
  8. 8.
    Farrar J, Hotez PJ, Junghanss T, Kang G, Lalloo D, White NJ (2013) Manson’s tropical diseases, 23rd edn. Elsevier Saunders, Philadelphia, pp 273–285Google Scholar
  9. 9.
    Lippi G, Plebani M (2012) EDTA-dependent pseudothrombocytopenia: further insights and recommendations for prevention of a clinically threatening artifact. Clin Chem Lab Med 50(8):1281–1285Google Scholar
  10. 10.
    Nagler M, Keller P, Siegrist D, Alberio L (2014) A case of EDTA-dependent pseudothrombocytopenia: simple recognition of an underdiagnosed and misleading phenomenon. BMC Clin Pathol 1(14):19CrossRefGoogle Scholar

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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