What is the white blood cell count and differential?
The white blood cell count and differential determine the number of white blood cells and the percentage of each type of white blood cell in a person's blood.
Why is differential white blood cell count more valuable than a total white blood cell count when trying to pin down the specific source of pathology?
A total white blood count gives a single number - how many white blood cells were present per milliliter of sample. A differential white blood count breaks the number down among the different white blood cell types - neutrophil, lymphocyte, monocyte, basophil, eosinophil. Different white blood cells will respond to different types of pathology - neutrophils are associated with bacterial infections, eosinophils with parasite infestation, monocytes with chronic infections, etc.
Most analysers provide an automated differential with the white cell count, red cell count, and indices. If for some reason, the differential is rejected, or flagged on the automated differential provided, the differential must be performed manually by properly trained technologists. A manual differential involves making a smear on a glass slide and staining the slide with Wright's stain which is a combination of acid and basic dyes. The stain results in white blood cells…
That indicates the bacterial infections, which are accessible to the white blood cells for phagocytosis. The viruses are always inside the cells. The white blood cell count is low. The malaria parasite is inside the red blood cell. The white blood cell count is low. The typhoid bacillus is inside the cell. The white blood cell count is low.