Megaloblastic anemia

Alternative names:

anemia - megaloblastic

Definition:

A blood disorder characterized by red blood cells that are larger than normal, low white blood count, and low platelet count resulting from a deficiency of folic acid or vitamin B-12.

Causes, incidence, and risk factors:

Deficiencies of vitamin B-12 and folic acid are the most common causes of megaloblastic anemia. Other causes are leukemia, myelofibrosis, multiple myeloma, certain hereditary disorders, drugs that affect nucleic acid metabolism such as chemotherapy agents (methotrexate), and other causes. Risk factors relate to the causes. (See also pernicious anemia).