Stress leukogram

Eosinopenia, neutrophilia and lymphopenia are commonly observed in patients with stress, including infection. The monocyte count may or may not be increased.
“Cheat sheet” for interpreting white cell differentials in the 2 cases below.
Example 1: Complete blood count from a patient with inflammation. Focus on the total white cell count (WBC, top row) and absolute counts for the white cell subsets (Abs, bottom row, right). AbsNeut, absolute neutrophil count; AbsLymp, absolute lymphocyte count; AbsMono, absolute monocyte count; AbsEos, absolute eosinophil count; AbsBaso, absolute basophil count. All counts are expressed as 109/L. Note that there is leukocytosis, neutrophilia, lymphopenia and eosinopenia. This is a classic profile for a stress response.
Example 2. Complete blood count from a different patient with inflammation. Focus on the total white cell count (WBC, top row) and absolute counts for the white cell subsets (Abs, bottom row). Abbreviations as per Example 1. Note in this case that the total white cell count is normal and that this belies a classic stress response seen in the differential with neutrophilia, lymphopenia and eosinopenia. This is a reminder that the white cell differential may contain helpful information even when the total white cell count is normal!

Effects of stress:

  • Immediate (seconds to minutes), total and differential leukocyte counts tend to increase in proportion to their normal circulating numbers from the effects of epinephrine.
  • Later (minutes to hours), neutrophil counts may be increased, while lymphocyte and eosinophil counts may be decreased, mediated primarily by endogenous glucocorticoids. Indeed, It is well established that corticosteroids can reduce eosinophils, raise neutrophils and reduce lymphocytes.
  • With more mild stressors, only one or two of these leukocyte changes may be observed.

Clinical applications:

  • Many studies have explored the utility of stress leukogram (express as neutrophil-to-lymphocyte-count ratio [NLCR] with or without eosinopenia) for diagnostic, prognostic or monitoring purposes in patients with various inflammatory disorders, including infections.
  • However, the stress leukogram is not specific for any of these conditions. It is also seen those with:
    • Infection
    • Acute pancreatitis
    • Acute myocardial infarction
    • Stroke
    • Acute trauma
    • Emotional stress
  • The lack of specificity limits the applicability of the stress leukogram to clinical practice.