Complete blood count
A laboratory test that measures the numbers and characteristics of red blood cells, white blood cells, and platelets in a blood sample.
Red blood cell: A blood cell that carries oxygen from the lungs to tissues, largely using hemoglobin. Red-cell count and related indices describe this cell population.
Automated hematology analyzer: An instrument that counts and classifies blood cells using techniques such as electrical impedance, light scattering, or fluorescence. It produces most routine complete blood count results from a blood sample.
Anemia: A condition in which blood has reduced oxygen-carrying capacity, commonly reflected by low hemoglobin. Low hemoglobin or hematocrit can prompt evaluation for anemia.
Basic metabolic panel: A blood test measuring substances such as electrolytes, glucose, and kidney-related markers. Unlike a CBC, it evaluates selected chemicals rather than blood-cell populations.
White blood cell: A blood cell involved in immune defense and other functions. The total white-cell count measures this diverse population.
Electrical impedance: A measurement of changes in electrical resistance as particles pass through an aperture. Some analyzers use cell-induced resistance changes to count and size blood cells.
Leukocytosis: An increase in the number of white blood cells above the expected range. An elevated white-cell count is described as leukocytosis.
Comprehensive metabolic panel: A blood test measuring electrolytes, glucose, kidney markers, proteins, and liver-related markers. It assesses chemical and organ-function markers not included in a CBC.
Platelet: A blood component derived from megakaryocytes that helps stop bleeding by forming plugs and supporting clotting. The platelet count reports the concentration of these clot-forming fragments.
Flow cytometry: A technique that measures physical and chemical features of cells as they pass individually through a laser beam. Optical cell analysis helps automated instruments distinguish blood-cell types.