Anemia occurs when a decreased number of red blood cells circulate throughout the body. It is the blood condition most common to the general population. Symptoms can include headaches, pale skin and chest pain.
It currently affects more than 3 million Americans worldwide, and an estimated 1.62 billion people.
Sometimes it occurs when certain conditions interfere with the ability of the body to produce healthy red blood cells, or abnormally increase degradation or loss of red blood cells.
Fast facts on anemia
Here are some key points about anemia. More detail is in the main article.
- Anemia affects an estimated 24.8 percent of the world’s population.
- Pre-school children have the highest risk, with an estimated 47 percent developing anemia, globally.
- More than 400 types of Anemia have been identified.
- Anemia is not restricted to humans and can affect cats and dogs.
A sense of exhaustion and a lack of strength are the most common symptoms of all forms of anemia.
Other common symptoms may include:
- paleness of skin
- fast or irregular heartbeat
- shortness of breath
- chest pain
For mild cases, signs can be minimal or no.
Some types of anemia can pose certain symptoms:
- Aplastic anemia: fever, frequent infections, and skin rashes
- Folic acid deficiency anemia: irritability, diarrhea, and a smooth tongue
- Hemolytic anemia: jaundice, dark colored urine, fever, and abdominal pains
- Sickle cell anemia: painful swelling of the feet and hands, fatigue, and jaundice
To live the body needs red blood cells. They bear hemoglobin which is a complex protein containing iron molecules. Those molecules deliver oxygen to the rest of the body from the lungs.
Some illnesses and conditions can lead to low red blood cell levels.
There are several forms of anemia and no common cause has been identified. Identifying the exact trigger can often be difficult.
Below is a general description of the common causes of anemia in the three major groups:
1) Anemia caused by blood loss
The most severe type of anemia – anemia with an iron deficiency – frequently falls into this category. It is caused by an iron deficiency, most likely because of blood loss.
When the body loses blood, in an effort to keep the blood vessels full it responds by removing water from tissues outside the bloodstream. The extra water is diluting the blood. The red blood cells can dilute as a result.
Blood loss can be chronic or acute and rapid.
Rapid loss of blood can involve surgery, conception, trauma or a ruptured blood vessel.
Chronic blood loss in cases of anaemia is more common. It may be caused by an ulcer in the stomach, cancer or tumor.
Causes of blood loss anaemia include:
- gastrointestinal conditions, such as ulcers, hemorrhoids, cancer, or gastritis
- use of non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen
- menstrual bleeding
2) Anemia caused by decreased or faulty red blood cell production
Bone marrow is a thick, spongy tissue that is located in the bone centre. This is important to the production of red blood cells. Bone marrow gives rise to stem cells that turn into red blood cells, white blood cells and platelets.
A variety of diseases can affect the bone marrow, including leukemia, where it produces too many defective white blood cells. That disrupts normal red blood cell development.
Other anemia caused by reduced or defective red blood cells include:
- Sickle cell anemia: Red blood cells fail and break down abnormally quickly. The crescent-shaped blood cells may also get trapped, causing pain, in smaller blood vessels.
- Iron-deficiency anemia: Too few red blood cells are formed because there is not enough iron in the body. This can be attributed to inadequate diet, menstruation, regular donation of blood, physical exercise, other digestive disorders, such as Crohn’s disease, surgical removal of part of the intestine and certain food.
- Problems with the bone marrow and stem cell: Aplastic anemia, for example, occurs when there are few to no stem cells. Thalassemia happens when red blood cells can’t expand properly and mature.
- Vitamin deficiency anaemia: vitamin B-12 and folate are both important to red blood cell growth. When one of these were insufficient, the development of red blood cells will be too poor. Examples include pernicious anemia and megaloblastic anemia.
3) Anemia caused by the destruction of red blood cells
Red blood cells usually have a 120-day life cycle in the bloodstream but can be killed or replaced in advance.
One form of anemia falling into this category is autoimmune hemolytic anemia, in which the body’s immune system mistakenly recognizes and attacks its own red blood cells as a foreign material.
Excessive hemolysis (red blood cell breakdown) can occur for a variety of reasons, including:
- certain drugs, for example, some antibiotics
- snake or spider venom
- toxins produced through advanced kidney or liver disease
- an autoimmune attack, for instance, because of hemolytic disease
- severe hypertension
- vascular grafts and prosthetic heart valves
- clotting disorders
- enlargement of the spleen
Anemia is handled in a number of ways. They all seek to raise the count of red blood cells. This in turn raises the amount of oxygen released by the blood.
Treatment depends on the type of anemia and its origin.
- Iron deficiency anemia: Iron supplements or dietary changes. If the condition is due to loss of blood, the bleeding must be found and stopped.
- Vitamin deficiency anemias: Treatments include dietary supplements and B-12 shots.
- Thalassemia: Treatment includes folic acid supplementation, removal of the spleen, and, sometimes, blood transfusions and bone marrow transplants.
- Anemia of chronic disease: This is anemia associated with a serious, chronic underlying condition. There are no specific treatments, and the focus is on the underlying condition.
- Aplastic anemia: The patient will receive blood transfusions or bone marrow transplants.
- Sickle cell anemia: Treatment includes oxygen therapy, pain relief, and intravenous fluids. There may also be antibiotics, folic acid supplements, and blood transfusions. A cancer drug known as Droxia or Hydrea is also used.
- Hemolytic anemias: Patients should avoid medication that may make it worse and they may receive immunosuppressant drugs and treatment for infections. Plasmapheresis, or blood-filtering, might be necessary in some cases.
There are more than 400 currently recognized forms of Anemia, and these are classified into three major classes according to their cause:
- Anemia caused by blood loss
- Anemia caused by decreased production or production of faulty red blood cells
- Anemia caused by the destruction of red blood cells
Types of anemia within these categories include:
- sickle cell anemia
- vitamin deficiency anemia
- iron deficiency anemia
- blood-loss anemia
- Cooley’s anemia
- pernicious anemia
If nutritional deficiencies cause the anemia, a transfer to an iron-rich diet will help relieve the symptoms. The following nourishments are high in iron:
- iron-fortified cereals and breads
- dark-green leafy vegetables, for instance, curly kale and watercress
- pulses and beans
- brown rice
- white and red meats
- nuts and seeds
- dried fruits, including apricots, raisins, and prunes
Anemia can occur in both male and female humans of all ages and sex. Some factors however increase the risk.
- pregnancy and childbirth
- being born preterm
- being aged 1 to 2 years
- having a diet that is low in vitamins, mineral, and iron
- losing blood from surgery or injury
- long-term or serious illness, such as AIDs, diabetes, kidney disease, cancer, rheumatoid arthritis, heart failure, and liver disease
- family history of inherited anemias, such as sickle cell anemia
- intestinal disorders-affects absorption of nutrients
An individual with anemia has an outlook that depends on the cause. Many cases of anemia may be avoided or cured by a dietary change.
Some types can last a long time and those without treatment can be life threatening.
Anyone who feels sick and exhausted persistently should see a doctor to test for anemia.
There are different ways of diagnosing anemia, but the most common is a blood test known as a full blood count (CBC).
This tests a variety of components of the blood, including hemoglobin and hematocrit levels, or the ratio of red blood cell volume to total blood volume.
A CBC will provide an indication of the general health of the person and whether he or she has any disorders like leukemia or kidney disease.
If the levels of red blood cells, hemoglobins, and hematocrites are all below “normal” levels, then anemia is probable.
It doesn’t have a definitive diagnosis, however. It can be out of the usual range but still safe.