What is Anemia?
Anemia results from a decreased number of red blood cells (RBCs) or a decreased quantity of hemoglobin in the blood. It is the most common blood disorder.
Classification of Anemia
Classification of anemia can be made by studying the morphology of RBCs, the underlying etiology, and the clinical symptoms. Based on the underlying etiology, anemia can be classified into two main types: anemia caused by the inadequate production of RBCs, and anemia caused by the excessive loss of RBCs
Table. Etiological classification of anemia1
INADEQUATE production of red cells
EXCESSIVE loss of red cells
- Caused by inadequate "raw materials"
- Iron deficiency
- Vitamin B12 deficiency
- Folic acid deficiency
- Caused by impaired function of bone marrow factory
- Anemia of chronic disease
- Bone marrow damaged or destroyed (aplastic anemia)
- Bone marrow replaced by foreign or abnormal cells (bone marrow replacement anemia)
EXCESSIVE loss of red cells
- Caused by external blood loss (hemorrhage)
- Caused by shortened survival of red cells in the circulation
Defective red cells (hereditary hemolytic anemia)- Abnormal red cell shape
- Abnormal hemoglobin within red cells
- Defective hemoglobin synthesis within red cells
- Deficient red cell enzymes
- "Hostile environment"
- Anti-red cell antibodies
- Mechanical trauma to circulating red cells
Reproduced from Crowley LV. Essentials of human disease. Sudbury, MA, USA. Jones and Bartlett Publishers; 2011. pp. 226-7 © 2011 Jones and Bartlett Publishers.
About Anemia | What is Anemia? | Iron Health Alliance: