First of all – What is anemia?
Anemia, according to Wikipedia’s definition, is “a decrease in normal number of red blood cells or less than the normal quantity of hemoglobin in the blood”.
What does this mean, in plain English?
First, red blood cells: Our body needs oxygen to function. This oxygen has to reach each and every organ in our body. The oxygen is placed inside our red blood cells, which travel throughout the body in our blood vessels and deliver the oxygen to all organs. The oxygen in the blood cells is carried in a special molecule called hemoglobin
Hemoglobin. Oxygen is delivered in it to all body parts. Photo by Zephyris.
As the definition above says, anemia can happen if one of these two things occurs:
- When you don’t have enough red blood cells – This can happen if you have less than the normal amount of blood (for example, when you bleed from somewhere in your body).
- When you have the normal amount of red blood cells, but not enough hemoglobin
How does anemia feel?
When you have anemia, not enough oxygen is delivered to your organs. This can cause fatigue, difficulty breathing when you do physical activity, and if you have a heart condition, it can even bring about angina pectoris.
People with anemia look pale. Their heart rates can be faster (the heart is trying to move more oxygen to the body, so it will move the blood faster). The blood pressure of people with anemia can change as well – it tends to fall when they stand up (“dizzy spells”).
According to the type of anemia (we’ll get to that later), other things can happen as well. This picture sums it up:
What are the causes?
There are many types of anemia. Its causes can be divided into two main groups:
Here’s a rundown of what’s in each group. Please note: Each of the diseases below will be featured in future posts and linked back here, so it’s worth bookmarking this page and returning to it from time to time.
Group 1 – Problems in the production of blood cells
There are a few diseases in this group:
- Iron deficiency anemia: This is a common cause of anemia. Iron is needed by the body to make hemoglobin. If you don’t have enough of it, the body can’t produce enough hemoglobin. Reasons for this include bleeding from somewhere in your body (such as when you hav
e a period), not eating enough foods that contain iron or problems in absorbing the iron, and times at which more iron is needed (such as during pregnancy).
- Thalassemia: This is a genetic disease in which there is a problem with the production of hemoglobin.
- Anemia of chronic inflammation: Sometimes, people with chronic diseases may have anemia due to their illness. Examples of such illnesses include chronic infections, HIV, cancers and others.
- Folate or vitamin B12 deficiency: Folate (folic acid) and B12 are needed for the production of red blood cells (as well as other cells in the body). If you have a deficiency in any of these, you’ll have anemia. Folate is present in leafy green vegetables and fruit, and B12 is present in foods of animal origin (such as meat. This is why vegetarians can have a deficiency).
- Other reasons: Other things can also cause problems in the production of red blood cells. These include liver diseases, alcoholism, problems with the thyroid gland, certain medications and others.
Group 2 – Increased destruction or loss of blood cells
- Blood loss – When you are injured and lose blood, such as after a car accident or a gunshot wound, you lose blood. This causes anemia and your body will not be able to transfer oxygen to your organs efficiently. That is why blood transfusions are often given after an injury.
- Hemolysis– This is a Greek word (hemo = blood, lysis = to break open) which means the destruction of red blood cells. There are a few diseases which cause this:a. G6PD Deficiency – A genetic problem which causes the red blood cells to be more susceptible to damage, which causes their destruction.
b. Sickle cell anemia – Another genetic disease. It causes the hemoglobin to have a strange shape, which causes the red blood cells to get destroyed.
c. Hereditary spherocytosis – Yet another genetic disease. In this disease there’s a change of shape in the cover of the red blood cells, which causes them to be more susceptible to destruction.
d. Paroxysmal nocturnal hemoglobinuria – A disease in which there’s a problem with the cells from which red blood cells are created.
e. Autoimmune hemolytic anemia – In this disease, antibodies (the molecules in our body responsible for fighting infections) attack the red blood cells and destroy them, for unknown reasons.
f. Microangiopathic hemolytic anemia – This is a complicated name for a groups of diseases. The common thing they all have is that the red blood cells are destroyed inside our blood vessels. Diseases here include thrombotic thrombocytopenic purpura (TTP), hemolytic uremic syndrome (HUS), and disseminated intravascular coagulation (DIC).
g. Hypersplenism – Our red blood cells don’t live forever. They live for about 120 days, and then get destroyed, mainly in the spleen. When our spleen gets bigger it tends to trap more red blood cells and so they get destroyed even when they are not old. Reasons for that includes tumors, infections and others.
How can the doctor tell if you have anemia?
First of all, if you have the right symptoms mentioned above, such as feeling tired and being pale.
Second, they will run a blood test, in which the hemoglobin will be low. (The normal values are 12-14 in women and 14-16 in men). Other lab tests help the doctor understand which anemia you have.