Anemias are blood disorders characterized by a reduced number of erythrocytes in a person’s blood. These conditions are also often connected to the low quality of hemoglobin and its deficiency (Huether & McCance, 2017). The most common type of anemia is iron-deficiency anemia (IDA), a microcytic disorder caused by bleeding or a poor diet (Hammer & McPhee, 2014). As a contrast, pernicious anemia is not defined by hemoglobin deficiency, being an autoimmune response of the body to inadequate stores of vitamin B 12. The two anemia types have different pathophysiological processes that result in similar outcomes for affected persons.
Pathophysiology of Anemia
One of the leading causes of IDA is blood loss. For example, menstruating women lose blood regularly, and excessive bleeding (menorrhagia) can lead to them having insufficient levels of stored iron (Hammer & McPhee, 2014). As the body aims to maintain a balance between utilized and stored iron, blood loss increases the need for iron, disrupting the usual processes. At first, the body does not recognize the shortage of iron, using the stored element until its quantity is depleted. Then, when the iron is no longer supplied to the bone marrow in adequate amounts, the body starts producing iron-deficient erythrocytes (Huether & McCance, 2017). As a result, these cells replace normal red cells, and the disorder manifests itself.
Pernicious anemia, on the other hand, is caused by the absence of a transporter, otherwise called intrinsic factor (IF), that is responsible for the absorption of vitamin B 12. The body needs this vitamin to synthesize DNA in erythrocytes (Hammer & McPhee, 2014). When the body is affected by autoimmune gastritis, it leads to the loss of IF and gastric acid and the destruction of parietal cells. As an outcome, the stores of B 12 in the liver start depleting because IF cannot transfer the vitamin. The synthesis of DNA becomes inadequate with time, and the produced erythrocytes become large and thick (Huether & McCance, 2017). Their defectiveness causes them to die quickly, creating a deficiency of red cells.
The two discussed types of anemia both lead to the body producing defective erythrocytes. However, in IDA, red cells are small with low amounts of hemoglobin, while in pernicious anemia, they have sufficient levels of hemoglobin but are large and short-lived (Huether & McCance, 2017). Furthermore, the causes of disorders and the mechanisms of their development differ as well. IDA can occur as a result of blood loss, dietary problems, or parasite infestations. As a contrast, pernicious anemia is an autoimmune condition linked to chronic atrophic gastritis.
Patient Factors
A variety of patient factors can affect both anemic disorders. IDA’s onset is strongly impacted by gender – females with menorrhagia are among the risk groups for developing this type of anemia (Shander et al., 2014). Older people and geriatric patients are also at risk of developing IDA due to blood loss and insufficient dietary intake. Children living in developing countries can be affected by infestations that increase the use of iron and lead to IDA (Huether & McCance, 2017). In the case of pernicious anemia, genetics play a significant role in the progression of this disorder. Both older and younger individuals can be affected by this condition although the majority of cases involve geriatric patients of Scandinavian, European, and African descent (Hammer & McPhee, 2014). One’s behavior is also a vital factor – smoking and exposure to lead or dangerous metals can exacerbate the development of pernicious anemia (Hernandez & Oo, 2015). In the case of IDA, one’s diet is the main behavioral factor that impacts the disorder.
Conclusion
Anemic disorders have different causes and pathophysiological processes while leading to a similar outcome – the deformation of erythrocytes. IDA is characterized by iron deficiency, while pernicious anemia is defined by the lack of B 12 in one’s body. IDA is much more common than pernicious anemia because the second type is an autoimmune condition that is tied to a set of particular body responses. However, both disorders are linked to the body not getting enough necessary resources.
References
Hammer, G. D., & McPhee, S. J. (2014). Pathophysiology of disease: An introduction to clinical medicine (7th ed.). New York, NY: McGraw-Hill Education.
Hernandez, C. M. R., & Oo, T. H. (2015). Advances in mechanisms, diagnosis, and treatment of pernicious anemia. Discovery Medicine, 19(104), 159-168.
Huether, S. E., & McCance, K. L. (2017). Understanding pathophysiology (6th ed.). St. Louis, MO: Mosby.
Shander, A., Goodnough, L. T., Javidroozi, M., Auerbach, M., Carson, J., Ershler, W. B.,… Lew, I. (2014). Iron deficiency anemia — Bridging the knowledge and practice gap. Transfusion Medicine Reviews, 28(3), 156-166.