A high absolute monocyte count can be the result of a viral infection such as
mononucleosis or measles. ... Monocytes are made in the
bone marrow of all bones. They account for approximately 1 to 10 percent of all the white blood cells found within the body.
Monocytes are a type of white blood cell that fight certain infections and help other white blood cells remove dead or damaged tissues, destroy cancer cells, and regulate immunity against foreign substances.
An increased number of monocytes in the blood (monocytosis) occurs in response to chronic infections, in
autoimmune disorders, in blood disorders, and in certain cancers. An increase in the number of macrophages in parts of the body other than in the blood (such as the lungs, skin, and other organs) can occur in response to infections, sarcoidosis, and
Langerhans cell histiocytosis.
The most common cause of an elevated RDW is anemia.
Higher RDW values indicate greater variation in size. Normal reference range of RDW-CV in human red blood cells is 11.5-14.5%. If anemia is observed, RDW test results are often used together with
mean corpuscular volume (MCV) results to determine the possible causes of the anemia.