Left shift
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Overview
Left shift or blood shift is an increase in the number of immature leukocytes in the peripheral blood, particularly neutrophil band cells.[1]
Less commonly, left shift may also refer to a similar phenomenon in severe erythroanemia, when reticulocytes and immature erythrocyte precursors appear in the peripheral circulation.[2]
Definition
Definition
The standard definition of a left shift is an absolute band form count greater than 700/microL.[3] The term itself refers to the historical practice, in paper laboratory reports, of recording band form counts on the far left side of the page.[reference needed]
Morphology
Morphology
It is usually noted on microscopic examination of a blood smear. This systemic effect of inflammation is most often seen in the course of an active infection and during other severe illnesses such as hypoxia and shock. Döhle bodies may also be present in the neutrophil’s cytoplasm in the setting of sepsis or severe inflammatory responses.[4]
Pathogenesis
Pathogenesis
It is believed that cytokines (including IL-1 and TNF) accelerate the release of cells from the postmitotic reserve pool in the bone marrow, leading to an increased number of immature cells.[1]
References
References
- ↑ 1.0 1.1 Kumar, Vinay; Fausto, Nelso; Abbas, Abul (2004). Robbins & Cotran Pathologic Basis of Disease (7th ed.). Philadelphia, PA: Saunders. pp. 84–85. ISBN 978-0-7216-0187-8.
- ↑ Rodak, Bernadette F.; Fritsma, George A.; Doig, Kathryn (2007). Hematology: clinical principles and applications (3rd ed.). Elsevier Health Sciences. p. 171. ISBN 978-1-4160-3006-5.
- ↑ Coates, Thomas D (December 22, 2008), “Approach to the patient with neutrophilia”, UpToDate Online, 17.3, Wolters Kluwer, retrieved December 21, 2009
- ↑ Kumar, Vinay; Fausto, Nelso; Abbas, Abul (2004). Robbins & Cotran Pathologic Basis of Disease (7th ed.). Philadelphia, PA: Saunders. pp. 663–664. ISBN 978-0-7216-0187-8.
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