The pathophysiologic classification system of anemia is divided into two broad categories. These categories are based on the underlying cause of the decrease in red blood cells (RBCs) in the circulation. The categories are:
- Anemia caused by decreased production of red blood cells.
- Anemia caused by increased destruction or loss of red blood cells.
Destruction of RBCs after release from the bone marrow occurs as a result of either an intracorpuscular abnormality or an extracorpuscular abnormality. Intracorpuscular abnormalities are the consequence of an abnormality in the red cell membrane, an enzyme, or globin chain (inherited condition). Extracorpuscular abnormalities are those that are secondary to a clinical condition (acquired condition).
The table below summarizes the pathophysiologic classification of anemia and provides examples in each category.