A novel method to estimate platelet counts from peripheral smears: A study comparing a new method of platelet estimation with existing methods.

Authors

  • Muthu Sudalaimuthu SRM Medical College Hospital and Research Centre, Potheri, Chennai-603203
  • Shivasekar Ganapathy SRM Medical College Hospital and Research Centre, Potheri, Chennai-603203
  • Koshalya Rajendran SRM Medical College Hospital and Research Centre, Potheri, Chennai-603203
  • Sundaram Arunachalam SRM Medical College Hospital and Research Centre, Potheri, Chennai-603203

Keywords:

Platelet, Platelet count, Thrombocytopenia, Hematology

Abstract

Background: Automated hematology analyzers have a low degree of accuracy in predicting platelet counts in patients with thrombocytopenia. Hence automated platelet counts should be crosschecked by reviewing the peripheral blood smear in cases of thrombocytopenia. However existing methods for platelet count estimation from peripheral blood smears have certain drawbacks. Hence we suggest a new method to estimate platelet count from peripheral smear and compared it with the existing methods.

 

Methods: Platelet count was estimated by four different methods in 200 blood samples and compared with the platelet count obtained from automated analyzer Sysmex XT-1800i. Method A was based on the platelet/Red Blood cell (RBC) ratio in ten oil immersion fields and multiplying it by  total RBC count, Methods B, C and D were based on the average number of platelets per oil immersion field. Platelet count was obtained by multiplying by 15000 in Method B, by 20000 in Method C, by hemoglobin value X 1000 in Method D. Results were analyzed by ANOVA, student’s t test and correlation coefficient.

Result: Results of Method A had a strong correlation with the automated blood counts (0.973). The results were not significantly different from the automated blood counts (p value of 0.798). Results of other methods were significantly different from automated platelet counts (p<0.05).

Conclusion: Platelet count estimation based on platelet/RBC ratio in ten oil immersion fields and total RBC count is a simple and reliable method to estimate platelet counts from peripheral smears.

 

DOI: 10.21276/apalm.2017.1159

Author Biographies

Muthu Sudalaimuthu, SRM Medical College Hospital and Research Centre, Potheri, Chennai-603203

Pathology

Shivasekar Ganapathy, SRM Medical College Hospital and Research Centre, Potheri, Chennai-603203

Pathology

Koshalya Rajendran, SRM Medical College Hospital and Research Centre, Potheri, Chennai-603203

Pathology

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Published

19-02-2017

How to Cite

1.
Sudalaimuthu M, Ganapathy S, Rajendran K, Arunachalam S. A novel method to estimate platelet counts from peripheral smears: A study comparing a new method of platelet estimation with existing methods. Ann of Pathol and Lab Med [Internet]. 2017 Feb. 19 [cited 2025 Jan. 14];4(1):A77-82. Available from: https://pacificejournals.com/journal/index.php/apalm/article/view/apalm1159

Issue

Vol. 4 No. 1 (2017)

Section

Original Article

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Copyright (c) 2017 Muthu Sudalaimuthu, Shivasekar Ganapathy, Koshalya Rajendran, Sundaram Arunachalam

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