Screening for EDTA-dependent deviations in platelet counts and abnormalities in platelet distribution histograms in pseudothrombocytopenia

Abstract

Screening for pseudothrombocytopenia caused by in vitro platelet clumping has been performed in 45,000 subjects attending a general hospital. In our region, the observed prevalence of EDTA-induced pseudothrombocytopenia in blood samples with an initial platelet count below 150 x 10(9)/l was estimated to amount to 0.1%. EDTA-induced pseudothrombocytopenia was confirmed by detection of platelet aggregates by means of microscopic evaluation from the blood smear. In routine investigations, pseudothrombocytopenia could be highly suspected when the Sysmex NE 8000 showed characteristic peculiarities in the white blood cell (WBC) scattergram and histogram. Platelet aggregation is avoided in such cases by the use of citrate as an anticoagulant instead of EDTA. Pseudothrombocytopenia was detected in 46 subjects. As a screening test for pseudothrombocytopenia, increased cut-off values derived from the WBC histogram demonstrated 90% sensitivity and 100% specificity. Automated flagging for platelet clumps, deviations reflecting MPV, or PDW abnormalities revealed lower scores with respect to sensitivity.

EDTA-Dependent Pseudothrombocytopenia and Unnecessary Transfusion in a Patient with Crimean-Congo Haemorrhagic Fever

“…Hastaya refrakter trombositopeni tanısıyla steroid tedavisi verildi. Ancak genel durumu çok iyi olmasına rağmen trombositopenisi sürdüğünden tedavinin beşinci gününde periferik kan yayması yapıldı ve her alanda [10][11][12] …”

“…Psödotrombositope-niye yol açma mekanizması tam olarak netleşmemiştir; ancak glikoprotein IIb/IIIa kompleksinin EDTA varlığında antikorlar tarafından tanındığına dair bir hipotez ileri sürülmüştür (4,9). EDTA'ya bağlı psödotrombositopeni rutin sağlık hizmeti veren hastanelerde %0.1 oranında saptanabilirken, trombositopeni etyolojisinin araştırıldığı merkezlerde bu oran %15-17'leri bulabilmektedir (7,10,11). Bu sonucun bu kadar yüksek olması, periferik yaymanın yapılmamasına ve kanların uzun süre bekletildikten sonra çalışılmasına bağlanmıştır.…”

High levels of heparin-platelet factor 4 antibodies in patients with pseudothrombocytopenia: risk of misdiagnosis

“…PTCP may be transient and can occur at any time in healthy subjects, or in medical or surgical patients. EDTA-dependant PTCP has an incidence of 0.1% in a general hospital [9]. PTCP has never been associated with a hemorrhagic diathesis, platelet dysfunction or thrombotic events.…”

Ethylenediaminetetraacetic acid-dependent pseudothrombocytopenia associated with neuroendocrine carcinoma: A case report

“…EDTA-PTCP has been observed in a general hospital, with a prevalence of 0.1% (2,3). It has been reported in patients with various diseases, including sepsis, multiple myeloma, acute myocardial infarction and breast cancer (4-7).…”