page_title: White blood cell differential
section_title: Automated differential
hierarchical_section_title: White blood cell differential / Types / Automated differential
caption_attribution_description: Labelled WBC scattergram from Sysmex automated hematology analyzer.
context_page_description: A white blood cell differential is a medical laboratory test that provides information about the types and amounts of white blood cells in a person's blood. The test, which is usually ordered as part of a complete blood count, measures the amounts of the five normal white blood cell types – neutrophils, lymphocytes, monocytes, eosinophils and basophils – as well as abnormal cell types if they are present. These results are reported as percentages and absolute values, and then they are compared against reference ranges to determine whether the values are normal, low, or high. Changes in the amounts of white blood cells can aid in the diagnosis of many health conditions, including viral, bacterial, and parasitic infections and blood disorders such as leukemia.
  White blood cell differentials may be performed by an automated analyzer – a machine designed to run laboratory tests – or manually, by examining blood smears under a microscope. The test was performed manually until white blood cell differential analyzers were introduced in the 1970s, making the automated differential possible.
context_section_description: Most hematology analyzers provide a five-part differential, enumerating neutrophils, lymphocytes, monocytes, eosinophils and basophils. Some instruments can also count immature granulocytes and nucleated red blood cells. Hematology analyzers measure various properties of white blood cells, such as impedance, light scattering parameters, and staining reactions. This data is analyzed and plotted on a scattergram, forming distinct clusters which correspond to white blood cell types. The number of points in each cluster describes the number of cells, and the shape of the clusters can indicate changes in cellular structure. The analyzer counts many more cells than are counted in a manual differential, resulting in improved precision. If abnormal features or cell populations that the analyzer cannot identify are present, the instrument can flag the results for manual blood smear review.
caption: Example of a white blood cell differential scattergram: differently coloured clusters indicate different cell populations
exif: {"Image Orientation": "Horizontal (normal)"}