Physiological basis
The WBC count and differential determine the total number of white blood cells as well as the percentage and absolute number of each type of white cell in a blood sample. It is typically generated by an automated laboratory hematology analyzer as part of the CBC panel.
Interpretation
Increased in: Acute infections, inflammatory disorders, acute and chronic leukemias, myeloproliferative disorders, solid tumor (paraneoplastic reaction), circulating lymphoma, tissue injury/necrosis, G-CSF stimulation, various drugs, corticosteroids, allergies, hypersensitivity reactions, stress, smoking.
Decreased in: Infections, constitutional and acquired myeloid hypoplasia, myelosuppression (eg, chemotherapy, radiation, various drugs), myelodysplasia, collagen vascular diseases, hypersplenism, cyclic neutropenia, autoimmune neutropenia, alcoholism.
Comments
There are five types of white cells, each with different functions: neutrophils, lymphocytes, monocytes, eosinophils, and basophils. Absolute counts for individual cell populations can be calculated from a combination of the WBC count and the percentage of each cell type from the differential.