Question 3.1

A blood film from a patient is reported as showing a left shift and toxic changes.
a) What is the likely diagnosis?
b) What is meant by a left shift?
c) What constitutes ‘toxic changes’?

(25% marks)

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College answer

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"Left shift and toxic changes" is some anachronistic terminology still used to describe the morphological changes which occur in neutrophils in response to a variety of (usually infectious) stressors.

Causes of this picture:

  • Sepsis
  • Haemorrhage (due to adrenergic mobilisation of marrow neutrophils)
  • Necrosis (of any sort, eg. ischaemia)
  • Bone marrow infiltration (i.e. insufficient space for proper maturation)
  • Anaemia (in an exaggerated haemopoietic reaction, the marrow releases a lot of immature cells, which include neutrophils)

Left shift is an increased proportion of immature granulocytes, predominantly neutrophils.

  • At any given time, one should have no more than 3-5% of one's neutrophils represented by such band forms.
  • If there is any more, that represents a "left shift", a change in the immature:mature ratio.
  • According to Wikipedia, the term originates from some sort of "left-most button arrangement of early cell sorting machines", where the least mature cells (myeloblasts) were assigned to the left-most button of the manual counter.

"Toxic changes" are morphological changes seen in neutrophils, which occur as a part of widespread neutrophil activation (usually in response to systemic infection). To call "toxic changes" on a blood film, the laboratory scientist needs to find at least two out of three of the following morphological changes:

  • Toxic granulation (an indicator of neutrophil immaturity)
  • Toxic vacuolation (an indicator of phagocytosis)
  • Döhle bodies (remnants of the rough endoplasmic reticulum)


Zieve, Philip D., et al. "Vacuolization of the neutrophil: an aid in the diagnosis of septicemia." Archives of internal medicine 118.4 (1966): 356-357.

Zini, G. "Abnormalities in leukocyte morphology and number." Blood and bone marrow pathology. Churchill Livingstone Philadelphia, 2011. 247-261.

Schofield, K. P., et al. "Quantitative cytochemistry of the toxic granulation blood neutrophil." British journal of haematology 53.1 (1983): 15-22.

Weiner, W., and Elizabeth Topley. "Döhle bodies in the leucocytes of patients with burns." Journal of clinical pathology 8.4 (1955): 324-328.

Kulkarni, M., T. Agrawal, and V. Dhas. "Histopathologic bodies: An insight." Journal of the International Clinical Dental Research Organization 3.1 (2011): 43.

Easton, J. A., and Ch Fessas. "The incidence of Döhle bodies in various diseases and their association with thrombocytopenia." British journal of haematology 12.1 (1966): 54-60.

Cawley, J. C., and F. G. J. Hayhoe. "The Inclusions of the May‐Hegglin Anomaly and Dohle Bodies of Infection: an Ultrastructural Comparison." British journal of haematology 22.4 (1972): 491-496.

Nierhaus, Axel, et al. "Revisiting the white blood cell count: immature granulocytes count as a diagnostic marker to discriminate between SIRS and sepsis-a prospective, observational study." BMC immunology 14.1 (2013): 1.