Routine examination that indicates the cellular composition of the white blood cells (leukocytes) in the blood. The percentages of the individual blood cell types are determined by microscopic counting of a blood smear. The white cells of normal blood include granulocytes (neutrophils, eosinophils, basophils), lymphocytes and monocytes. The differential blood count plays an important role in the diagnosis of blood diseases, but also infections and inflammations. The determination of the differential blood count is necessary, among other things, to clarify leukocytopenia or leukocytosis.