Complete blood count (CBC) or full blood count (FBC), is a series of medical laboratory tests designed to provide essential information about the cells in an individual's blood. CBC indicates the amount of red blood cells, white blood cells, and platelets, along with the concentration of hemoglobin and the hematocrit (the volume percentage of red blood cells). Additionally, it assesses the red blood cell indices, indicating the average size and hemoglobin content of these cells. In some cases, a white blood cell differential is included to enumerate the various types of white blood cells.
The CBC is routinely performed as part of a medical evaluation and serves multiple purposes, such as monitoring overall health or identifying underlying diseases. The results are typically interpreted by comparing them to established reference ranges, which can vary according to gender and age. Abnormal CBC results may detect medical conditions like anemia and thrombocytopenia. The red blood cell indices provide clues about the underlying causes of anemia, such as iron deficiency or vitamin B12 deficiency, while the white blood cell differential results aid in diagnosing viral, bacterial, and parasitic infections, as well as blood disorders like leukemia. However, it's important to note that not all results falling outside the reference range necessarily require medical intervention.