Abstract:

Abstract:Objective To investigate the dissociative effect of amikacin sulfate on platelet aggregation in patients with EDTA-dependent pseudothrombocytopenia (EDTA-PTCP),and develop an effective method for accurate platelet counting in this kind of samples. Methods Amikacin sulfate was added or not to the EDTA-K2 anticoagulated tube before collecting venous blood in an infrequent patient with EDTA-PTCP,and the platelet counts and other blood cell parameters at different time after blood withdrawal were examined by automatic cytoanalyzer. Amikacin was added at different time after collecting EDTA-K2 anticoagulated blood samples,and dissociative effect of amikacin on the platelet aggregation and the platelet morphological changes on the blood smear were observed.Results The platelet counts of EDTA-PTCP blood sample without amikacin were gradually reduced from 117×10⁹ L^-1 to 41×109 L^-1 with extending time (0.5-4.0 h) after blood withdrawal.In the blood sample pre-supplemented with amikacin,the platelet counts were within range of the normal reference values,and the platelet counts were relatively stable within 4 h at room temperature after blood drawn.When amikacin was added within 30 min after blood sampling,the platelet counts （186×10⁹ L^-1 -191×10⁹ L^-1 ）were within the  range of the normal reference values,the obvious platelet dissociation on the blood smear were found.When amikacin was added over 30 min after blood drawn,the platelet counts were gradually reduced from 168×10⁹ L^-1  at 40 min after standing  to 42×10⁹ L^-1 at 4 h after standing,and smear examination revealed significantly the platelet aggregation.Conclusion Amikacin sulfate is added either before blood withdrawal or within 30 min after blood sampling,the platelet counts of the patient with EDTA-PTCP examined by automatic cytoanalyzer are accurate and the determination of other blood cell parameters is not influenced.

Key words: amikacin sulfate;EDTA-dependent pseudothrombocytopenia;dissociation, automated hematology analyzer