Left Shifted Blood

• Left shifted blood is blood that contains an abnormal number of immature blood cells.
  • Immature blood cells include immature neutrophils such as bands, metas, cytes, pros, or blasts.
  • Immature blood cells also include immature RBCs such as reticulocytes or nucleated RBCs (such as erythroblasts).
• These immature blood cells are present because bone marrow production of blood cells is occurring at an abnormally rapid rate.
• Blood cell production occurs at an abnormally rapid rate when the body is trying to increase the number of blood cells.
  • An example of the body trying to increase blood cell numbers is when the body is trying to increase the WBC count to battle infection.
    • Thus, the increased WBC count seen in bacterial infection should be accompanied by a left shift, that is, an increase in the number of immature neutrophils (bands etc.) seen in the blood.
  • Another example of the body trying to increase blood cell numbers is the body trying to increase the RBC count in response to the hemolytic anemia seen in in sickle cell.
    • Thus, blood in the sickle cell patient should show a left shift, that is, an increase in the number of immature RBCs (reticulocytes and Nucleated RBCs) seen in the blood.