Effective prevention of pseudothrombocytopenia in feline blood samples with the prostaglandin I 2 analogue Iloprost

BMC Veterinary Research

Hans Lutz¹  Regina Hofmann-Lehmann¹  Sonja Hartnack²  Andrea Katharina Waßmuth¹  Barbara Riond¹ 

[1] Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, 8057, Switzerland;Section of Epidemiology, Vetsuisse Faculty, University of Zurich, Zurich, 8057, Switzerland

关键词: Platelet aggregates;    Pseudothrombocytopenia;    Prostaglandin I2-analogue;    Platelets;    Iloprost;    Feline EDTA blood;   

Others  :  1224399
DOI  :  10.1186/s12917-015-0510-x

 received in 2015-03-10, accepted in 2015-07-28,  发布年份 2015

【 摘 要 】

Background

In vitro platelet aggregation in feline blood samples is a well-known phenomenon in veterinary clinical laboratories resulting in high numbers of pseudothrombocytopenia. Several attempts have been made to prevent or dissolve platelet aggregates in feline blood samples and to increase the reliability of feline platelet counts. Prostaglandin I ₂(PGI ₂ ) is the most powerful endogenous inhibitor of platelet aggregation but unstable. Iloprost is a stable PGI ₂analogue. The aims of the present study were (1) to evaluate the anti-aggregatory effect of Iloprost on feline platelet counts and to determine a useful concentration to inhibit platelet aggregation in EDTA samples from clinically healthy cats, (2) to investigate the effect of Iloprost on hematological blood parameters, and (3) to determine stability of Iloprost in K3-EDTA tubes for up to 16 weeks. From 20 clinically healthy cats blood was drawn from the jugular vein and immediately distributed in a 1.3 ml K ₃ -EDTA tube, and two 1.3 ml K ₃ -EDTA tubes containing 20 ng and 200 ng Iloprost, respectively. A complete blood cell count was performed on the Sysmex XT-2000iV and the Mythic 18 on eight consecutive time points after collection. Blood smears were evaluated for the presence of PLT aggregates.

Results

In the absence of Iloprost, pseudothrombocytopenia was observed in 50 % of the investigated samples that led to significantly decreased optical PLT counts by a mean of 105 x10 ³ /μl, which could be prevented by the addition of 1 μL (20 ng) Iloprost leading to an increase in PLT counts by a mean of 108 x10 ³ /μl.

Conclusion

This is the first study showing an anti-aggregatory effect of the PGI ₂ -analogue Iloprost in feline EDTA blood. In all clinically healthy cats investigated, pseudothrombocytopenia was prevented by adding Iloprost to EDTA tubes prior to blood collection. Furthermore, Iloprost was very useful in preventing falsely increased WBC counts in samples with platelet aggregates analyzed on impedance-based hematological instruments. Iloprost is preferable to PGI ₂or PGE ₁due to its stability and easy and safe handling properties. Cytological evaluations of blood smears as well as other hematological parameters were not influenced to a clinically significant degree by the presence of Iloprost.

【 授权许可】

   
2015 Riond et al.

【 图 表 】

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