A STUDY OF EDTA DEPENDENT PSEUDOTHROMBOCYTOPENIA

Abstract

Objective: To find out the frequency of Ethylenediaminetetraaceticacid (EDTA) Dependent   Pseudothrombocytopenia   (EDTA-PTCP)   in   all   blood counts

Material and Methods: 130 cases of suspected EDTA-PTCP were assessed for its correctness using manual platelet count as the gold standard, and compared the platelet counts in two different anticoagulants (EDTA and CPT) at different times from the time of collection of blood sample. The collected data was analysed and statistics were made accordingly.

Result: Total 151750 haemograms were done during the study period of which 2428 cases showed thrombocytopenia, accounting for 1.6%. Amongst these, the pseudothrombocytopenia was suspected in 130 cases and was found to be correct in 119 cases, thus accounting for the incidence of EDTA-PTCP in 0.07% cases of total haemograms and 4.9 % cases of total thrombocytopenia. In 11 cases, the suspicion of Pseudothrombocytopenia was found to be incorrect. Of the total 130 cases included in the study, with M: F ratio of 1:1.3. The age of the patients varied from 3-85 years with the mean age of 36.78 ± 20.33 years

Conclusion: In all the cases of thrombocytopenia showed by automated blood cell counters,  the  examination  of  peripheral  blood  film  is  must  for  the presence of platelet clumps to detect the cases of EDTA- dependent Pseudothrombocytopenia. To get correct platelet count in these cases, the manual platelet count is the ‘gold standard’. CPT is the better alternative anticoagulant for EDTA in cases of EDTA –PTCP for automated platelet counts.

Keywords: EDTA-PTCP,  haemogram, CPT,  exvivo agglutination