Kanamycin treated-ethylenediamine tetraacetic acid (EDTA)-dependent pseudothrombocytopenia in blood specimen of cats

Abstract

Background: Pseudothrombocytopenia is a commonly obtained false negative result when analyzing feline platelet count by automated machine. It is related to ethylenediamine tetra-acetic acid (EDTA), a widely utilized anticoagulant in blood collection tube, resulting in EDTA-dependent pseudothrombocytopenia (EDTA-PTCP). Aim: To investigate whether treated with kanamycin enhanced the quantity of platelet aggregations in feline blood specimens collected using EDTA-PTCP. Methods: Thirty-one blood samples were obtained using EDTA tubes. The complete blood count was analyzed using automated Mindray-BC-5000Vet. Both Manual cell counts and thin blood smears were performed to estimate the amount of RBC, WBC and platelets as well as to evaluate the severity scores of platelet clumping, respectively. Comparisons were made between those pre-treated and treated with kanamycin in EDTA tube. Results: There were significantly different mean platelet counts in the samples before and after they were treated with kanamycin, both on automated (156.6  76.4 vs 260.3  115.5; p < 0.001) and manual (168.5  92.1 vs 262.8  119.6; p < 0.001) readings, with a 95% confidence interval (CI) of 0.19 (0.022–0.365). Conclusion: This study suggests that in clinical laboratory practice, kanamycin should be added to feline blood specimens with EDTA-PTCP.