Anaemia due to destruction of red blood cells

Hello there, we are back once again. Today we will be discussing about how the destruction of red blood cells leads to anaemia or to be more specific hemolytic anaemia. Hemolytic anaemia happens when the red blood cells are destroyed prematurely. The usual life span of a healthy red blood cell is about 110-120 days but for hemolytic red blood cells the life span can be as short as five days! The bone marrow, a soft, spongy tissue inside of the bones that produces red blood cells, is unable to keep up with the fast rate at which the red blood cells are being destroyed and thus this leads to a drop in red blood cell count in patients with anaemia.

There are a few problems that causes hemolytic anaemia. These include:

Inherited abnormalise in the red blood cell membrane	The red blood cell membrane holds all the fluid within the cell and helps to maintain it’s biconcave shape. When there is a defect, it causes the red blood cell to change its shape, causing the spleen, the site where red blood cells are being destroyed, to recognise them as abnormal and therefore destroying them. Eg. Hereditary sherocytosis (a genetic disorder of the red blood cells where its surface area is smaller than normal and this causes it to break more easily)
Inherited enzyme deficiencies inside the red blood cells	Abnormal levels of enzyme in the red blood cell causes the red blood cell to be fragile and thus easily destroyed by the spleen. Eg. Glucose-6-phosphate dehydrogenase (G6PD) deficiency (the red blood cells do not produce sufficent G6PD/ the enzyme produced is abnormal and does work well).
Physical damage to red blood cells	Red blood cells might be damanged due to circumstances such as: during a heart and lung surgery when red blood cells flow past devices that are implanted into patient’s body especially artificial heart valves patients who experience server burns might cause red blood cells to be damaged due to exposure of extreme heat
Hypersplenism	Under such conditions, the spleen in patient’s body is overactive and enlarged and it traps the circulating red blood cells and destroys them even before their lifespan is up.
Hemoglobin disorders	Hemoglobin is a protein found within the red blood cell that binds to oxygen. Sometimes patients might obtain a gene that causes the hemoglobin to be abnormal which leads to disorders such as sickle cell anaemia (which was explained in the previous blog post) and thalassemia (a disorder in which red blood cells are rapidly destroyed and the iron is deposited at the vital organs of the body).
Autoimmune hemolytic anaemia	The immune system mistakes the red blood cells as foreign invaders and thus destroys its own red blood cells. This can be caused by conditions such as lupus (inflammatory disease that causes one’s body immune system attack the body’s tissues and organs), certain types of medication and infections.

Having said all these, there are some special cases when the cause is left unknown. But we hope that the past few blog posts has helped you better understand the three main causes of anaemia. Do stay tune for more updates from us as we explore more about the science of anaemia. Till then, take care and all the best in school (:

- ANNEBIGAIL :)

References:

http://www.drugs.com/health-guide/hemolytic-anemia.html

http://kidshealth.org/parent/medical/heart/anemia.html#

http://www.mayoclinic.org/diseases-conditions/lupus/basics/definition/con-20019676

http://www.thecambodiaherald.com/images/upload/health/NGYwMjE4ZDIyMTgzYTRkMTVkZDhlZDZiZDk5ZTRl/760_450/Splenomegaly.jpg