Red cell distribution width as a marker of activity in inflammatory bowel disease: a narrative review.

Red blood cell distribution width is a parameter measured automatically in every complete blood count that actually reflects the degree of anisocytosis of the red blood cell population. It is a cost-effective tool used in everyday clinical practice along with other parameters to define and narrow the cause of anemia. In a series of pathologic entities, such as cardiovascular diseases, autoimmune diseases, malignancy, chronic renal diseases and chronic respiratory diseases, where inflammation and oxidative stress comprise the major pathophysiologic insults, red cell distribution width behaves as a significant and competent marker able to predict and assess disease activity and severity.