Comparison of the peripheral blood eosinophil count using near-patient testing and standard automated laboratory measurement in healthy, asthmatic and COPD subjects

Abstract

Near-patient testing (NPT) allows clinical decisions to be made in a rapid and convenient manner and is often cost effective. In COPD the peripheral blood eosinophil count has been demonstrated to have utility in providing prognostic information and predicting response to treatment during an acute exacerbation. For this potential to be achieved having a reliable NPT of blood eosinophil count would be extremely useful. Therefore, we investigated the use of the HemoCue^® WBC Diff System and evaluated its sensitivity and specificity in healthy, asthmatic and COPD subjects. This method requires a simple skin prick of blood and was compared to standard venepuncture laboratory analysis. The HemoCue^® WBC Diff System measured the peripheral blood eosinophil count in healthy, asthma and COPD subjects with very close correlation to the eosinophil count as measured by standard venepuncture. The correlations were unaffected by disease status. This method for the measurement of the peripheral blood eosinophil count has the potential to provide rapid near-patient results and thus influence the speed of management decisions in the treatment of airway diseases.

Keywords:

• asthma
• chronic obstructive pulmonary disease
• eosinophils
• near-patient testing

Acknowledgments

The authors would like to acknowledge all the volunteers for their assistance in this study. Mona Bafadhel is funded by a National Institute of Health Research (NIHR) Post-doctoral Fellowship (PDF-2013-06-052). This paper presents independent research funded by the National Institute of Health Research and the views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health.

Author contributions

All authors contributed toward data analysis, drafting and critically revising the paper, gave final approval of the version to be published, and agree to be accountable for all aspects of the work.

Disclosure

MB and REKR have received honoraria from AstraZeneca, Boehringer Ingelheim, Chiesi, Novartis and Pfizer, and report no other conflicts of interest in this work. KH, CMC, CB, JHD, and HPJ report no conflicts of interest in this work.