Anemia is a disorder characterized by an abnormally low number of healthy red blood cells in the blood. Red blood cells carry oxygen throughout the body, so an insufficient number of red blood cells can have serious consequences.
Iron deficiency anemia (caused by iron deficiency) is the most common type of anemia. It is very common among children and women of all ages – especially women who are still menstruating. It is estimated that at least one-fifth of women in North America suffer from iron deficiency. It can also affect men significantly when it is caused by polyps or cancers of the colon or other gastrointestinal malignancies (cancers). Iron deficiency anemia is often one of the first warning signs of gastrointestinal cancer.
Sickle-cell anemia (sickle- shaped red blood cells) is another well-known type of anemia. Many millions of people around the world suffer from it. It is a hereditary condition, passed from parents to their children through defective genes. The people most often affected have ancestors from Africa, the Middle East, Mediterranean countries or India. Every year in the United States, 1 out of 12 African-American babies is born with the genetic potential to transmit sickle cell anemia. It is estimated that in the African-American population, one in 400 births will produce a newborn with Sickle Cell Anemia.
Aplastic anemia is a rare disorder that occurs when the bone marrow no longer produces any of the blood cells. This type of anemia is very serious, but also rare, fortunately. The incidence of this disorder is 2 to 12 new cases per million people per year. Adults and children can be affected by this type of anemia.
Inflammatory anemia is a mild type of anemia affecting people with illnesses lasting for more than 1 to 2 months. The diseases concerned include tuberculosis, HIV, cancer, kidney and liver diseases and rheumatologic disorders.
Pernicious anemia is a more common type of anemia in the elderly and is caused by a dietary vitamin B12 deficiency or poor absorption of this vitamin by the intestines. This condition is also frequently encountered in alcoholics.
Anemia is not a disease in itself, but rather a condition attributable to other health conditions. Anemia can be the consequence of three disorders:
In North America, blood loss is the most common cause of anemia. Many women have borderline anemia, in general, because their diets do not provide enough nutrients to replace the monthly menstrual bleeding. Gastrointestinal bleeding is another common cause of blood loss; these bleeds may be due to diseases such as ulcerative colitis, diverticulitis and colon cancer. Certain medications such as acetylsalicylic acid (ASA) and no steroidal anti-inflammatory drugs can also cause gastrointestinal bleeding.
The following conditions can also cause hemorrhaging:
- gastric ulcers;
- Hookworms (hookworm).
Inadequate production of healthy red blood cells
The body needs iron to produce hemoglobin, the protein found in red cells that carry oxygen from the lungs to the rest of the body. Hemoglobin also gives blood its red color. Similarly, vitamin B12 and folic acid deficiencies are often observed.
Even though these deficiencies are rarer in North America, they still exist. People who need increased iron intake include infants, pregnant women and teens that experience a growth spurt. Poor persistent bleeding can also lead to iron deficiency anemia. Even a healthy person can lose a small amount of blood every day in his stool. A slightly larger blood loss can easily go undetected and cause anemia.
The cause of inflammatory anemia is not fully known. It is linked to a decrease in the production of red blood cells.
The lifespan of a red blood cell is only about four months, and the red blood cells need to be replaced by new ones, which are produced in the bone marrow. You have aplastic anemia if your bone marrow is destroyed or if it has been severely injured and can no longer produce red blood cells. Some medications as well as radiation can destroy the bone marrow, but the most common cause is an autoimmune reaction. Such a reaction occurs when the cells that protect the body against the disease attack the person’s own tissues. In 50% of cases, the cause of the autoimmune reaction is unknown.
Other diseases can destroy bone marrow and cause aplastic anemia, including viral hepatitis and severe rheumatoid arthritis. The Fanconi disease is a rare inherited aplasia, characterized by abnormalities in the bone marrow. Anemia is common in people with severe kidney problems because the kidneys secrete a hormone called erythropoietin, which causes the bone marrow to produce red blood cells when the body needs it. In case of kidney trouble, the kidneys cannot produce enough of this hormone so that the body is properly fed red blood cells, resulting in anemia.
Rapid destruction of red blood cells
When healthy, the bone marrow produces a specific amount of red blood cells every month. If the destruction of red blood cells is faster than the rate of production, anemia sets in. The old red blood cells are mostly degraded by the spleen, the organ that filters the blood, verifies that it is not infected, and eliminates the harmful substances. Some conditions cause an increase in the volume of the spleen. For example, liver disease or lupus is two possible causes of hypersplenism (increased spleen volume); malaria and tuberculosis are two others. When the spleen is larger than normal, it retains and destroys healthy red blood cells, causing anemia.
Sickle cell anemia and thalassemia are two inherited disorders characterized by an abnormal type of red blood cells. Sickle cell anemia is widespread among people of African American descent, while thalassemia is more common in families of Mediterranean origin. Sickle cell anemia occurs in a person who receives from his father and mother a copy of the gene coding for sickle-cell red blood cells, which results in the production of red blood cells that are grossly abnormal in shape. The spleen recognizes these red blood cells as abnormal, and it must work harder and harder to eliminate these globules, which causes an increase in the volume of this organ. This anomaly causes anemia.
Anemia can be caused by a combination of factors: Anemia is widespread in people with cancer. In fact, about half of people with cancer develop anemia. The causes can be multiple and include bone marrow tumors, blood loss, dietary deficiency, chemotherapy and radiation that destroy the bone marrow where red blood cells are produced, or a combination of these factors.
In people with severe kidney disease, anemia is caused by the combination of decreased red blood cell production, reduced red blood cell lifespan, and blood loss associated with dialysis treatment.
Symptoms and Complications
The symptoms of anemia vary according to the importance of the decrease in the number of red blood cells in the blood.
Menstrual bleeding or iron deficiency tends to cause mild chronic anemia, the symptoms of which are fatigue, pallor and weakness.
If the anemia is caused by severe bleeding, such as severe ulcer gastrointestinal bleeding, you may feel dizzy and very weak, especially if you suddenly go into a standing position.
In case of severe anemia, the tissues and organs may be completely deprived of blood and oxygen. If so, the cells die quickly during a process called ischemia.
As we have explained, in sickle-cell anemia red blood cells, which are normally rounded in shape, look like a sickle. Because of this abnormal type, the cells remain blocked in the small blood vessels and hinder the normal flow of blood. People with this condition can suffer from severe ischemia in the feet, which sometimes leads to amputation, or other organs, which causes pain. People with this type of anemia are at high risk of having a stroke because sickle cells can easily clump together and type a clot that blocks the flow of blood into the vessels of the brain.
In people with cancer, the most common symptoms of anemia are fatigue and shortness of breath. It can be difficult for these people to continue their activities and maintain their usual energy level, which can have very negative effects on activities of daily living.
Your doctor will take a blood sample and send it to the laboratory for hemoglobin levels in the blood. The result is expressed as the number of grams of hemoglobin per liter of blood. The number of white blood cells, platelets and other blood elements will also be measured. The lab technologist will also examine the size and shape of the red blood cells.
The results of these tests tell the doctor about the number of different blood cells in the blood and their shape, which provides clues to the cause of anemia. For example, numbers of white blood cells and red blood cells below normal can be a sign of damage to the bone marrow or spleen. The doctor then looks for other diseases, depending on the results of the first blood test.
Treatment and Prevention
The choice of treatment for anemia is determined by the underlying disease that causes this anemia. Severe bleeding is usually treated with blood transfusions. If you have a serious type of chronic anemia, such as Fanconi’s disease or sickle cell anemia, you may also need to receive regular blood transfusions.
The life expectancy of people with sickle cell anemia has been greatly improved. In the old days, young people often did not reach adulthood.
Iron supplements are given to treat iron deficiency anemia. It is often noted that infants with this type of anemia receive typeula milk bottle. The infant’s body can absorb more iron in breast milk than in cow’s milk. Nursing mothers may take iron supplements. The latter are also useful for treating mild anemia caused by gastrointestinal bleeding or menstrual bleeding.
Vitamin B12, vitamin C and folic acid all play a crucial role in the production of red blood cells. Deficiency of any of these vitamins carries a risk of anemia. Beef and fish are good sources of vitamin B12. Vegetables do not contain this vitamin; a person who does not eat meat, fish or dairy products needs to take a vitamin B12 supplement. Folic acid is present in spinach, green peas, oranges and cantaloupes.
When anemia is caused by a reduction in the production of red blood cells, such as cancer or severe kidney disease, medications called epoetin alfa and darbepoetin alfa may be used. These medications mimic the action of the natural hormone erythropoietin which results in increased production of red blood cells by the bone marrow.
Healthcare Administrator is a website designed to accompany you through the process of reconstructing your life.