Anemia can be classified by cytometric methods, based on the morphology of red blood cells (RBCs), erythrokinetic schemes (the rates of RBCs production and destruction) and biochemical or molecular methods (the etiology of the anemia at the molecular level).

Cytometric Classification

In the morphological approach, anemia is classified by the size of RBCs on microscopic examination of a peripheral blood smear. The size is reflected in the mean corpuscular volume (MCV).Theamount of hemoglobin relative to the size of the cell (hemoglobin concentration) per RBC is known as mean corpuscular hemoglobin concentration (MCHC) and mean cell hemoglobin (MCH), which reflects the hemoglobin amount per RBC. The cytometric classifications are as following:

Erythrokinetic Classification

The erythrokinetic classification is based on the rate of RBCs turnover. If this rate is high, a normoregenerative anemia occurs which are seen in hemolysis (excess destruction of RBCs) or hemorrhage (loss of RBCs from the vascular compartment).

In these cases, the bone marrow responds by increasing the production of RBCs and releasing them into the bloodstream prematurely.

Several lab tests can help to determine the increased RBCs turnover such as:

Biochemical Classification

This categorization is based on the etiology of the anemia (will be discussed below). In a typical case of IDA, the biochemical indicators include serum iron, serum transferrin, transferrin saturation, serum ferritin and serum circulating transferrin receptor.

Generally, biochemical tests are aimed at identifying a depleted cofactor necessary for normal production of RBCs (iron, ferritin, folate and vitamin B₁₂), an abnormally functioning enzyme (glucose-6-phosphate dehydrogenase, pyruvate kinase), or abnormal function of the immune system (Coombs test).

Written by: Healthplus24 team
Date last updated: July 03, 2011