8. Spurious Counts and Spurious Results on Hematology Analyzers: White Blood Cells, Red Blood Cells, Hemoglobin, Red Cell Indices, and Reticulocytes

  1. Kandice Kottke-Marchant MD, PhD2,3,4 and
  2. Bruce H. Davis MD5
  1. Marc Zandecki PhD,
  2. Franck Genevieve MD,
  3. Jérémie Gérard PhD and
  4. Alban Godon MD

Published Online: 8 AUG 2012

DOI: 10.1002/9781444398595.ch8

Laboratory Hematology Practice

Laboratory Hematology Practice

How to Cite

Zandecki, M., Genevieve, F., Gérard, J. and Godon, A. (2012) Spurious Counts and Spurious Results on Hematology Analyzers: White Blood Cells, Red Blood Cells, Hemoglobin, Red Cell Indices, and Reticulocytes, in Laboratory Hematology Practice (eds K. Kottke-Marchant and B. H. Davis), Wiley-Blackwell, Oxford, UK. doi: 10.1002/9781444398595.ch8

Editor Information

  1. 2

    Pathology & Laboratory Medicine Institute, Cleveland, OH, USA

  2. 3

    Department of Pathology, Cleveland Clinic Lerner College of Medicine, Cleveland, OH, USA

  3. 4

    Hemostasis and Thrombosis, Department of Clinical Pathology, Cleveland Clinic, Cleveland, OH, USA

  4. 5

    Trillium Diagnostics, LLC, Bangor, ME, USA

Author Information

  1. Laboratoire d'Hématologie, Centre Hospitalier Universitaire, Angers, France

Publication History

  1. Published Online: 8 AUG 2012
  2. Published Print: 10 APR 2012

ISBN Information

Print ISBN: 9781405162180

Online ISBN: 9781444398595

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Keywords:

  • hematology analyzers;
  • automated count;
  • complete blood count;
  • spurious count;
  • white blood cells;
  • hemoglobin;
  • red blood cells;
  • mean cell volume

Summary

Hematology analyzers provide quick and accurate results in most situations. However, spurious results, related either to platelets or to other parameters from the complete blood count (CBC) may be observed in several instances. Spuriously low white blood cell counts (WBC) may be observed because of agglutination in the presence of ethylene diamine tetraacetic acid (EDTA). Cryoglobulins, lipids, insufficiently lysed red blood cells, erythroblasts, and platelet aggregates are common situations that increase WBC. In most of these instances flagging and/or an abnormal white cell differential scattergram will alert the operator.

Several situations lead to abnormal hemoglobin measurement or to abnormal red blood cell count (RBC), including lipids, agglutinins, cryoglobulins and elevated WBC counts. Mean cell volume (MCV) may also be subject to spurious determination because of agglutinins, an excess of glucose or salts, and technologic considerations. In turn, an abnormality related to one measured parameter will lead to abnormal calculated red cell indices: mean cell hemoglobin content (MCHC) is the most important to consider.

In many circumstances, several of the measured parameters from the CBC may be altered, and the discovery of a spurious change in one parameter frequently means that the validity of other parameters should be considered. Sensitive flags now allow the identification of several spurious counts, but only the most sophisticated hematology analyzers have optimal flagging and more simple analyzers, especially those without a white cell differential scattergram, do not possess the same sensitivity for detection of anomalous results. Reticulocytes are integrated now into the CBC in many hematology analyzers, and several situations may lead to abnormal counts.