ANEMIAS

DEFINITION

Anemia is a condition characterized by abnormally low levels of red blood cells.

DESCRIPTION

Cells require a constant supply of oxygen in order to stay healthy. Oxygen is delivered to cells by red blood cells, which pick up oxygen in the lungs. They carry the oxygen to cells through the bloodstream.

The oxygen-carrying molecule in red blood cells is hemoglobin (pronounced HEE-muh-glo-bin). Hemoglobin is a large, complex molecule. It contains an atom of iron at its center. Iron attaches itself easily to oxygen atoms. It is the iron in hemoglobin that actually carries oxygen to cells.

Anemia develops when the body has an insufficient supply of red blood cells and hemoglobin. When that happens, cells do not get the oxygen they need and begin to die off. A variety of medical problems may develop.

Types of Anemia

More than four hundred different kinds of anemia have been identified. Many of them are rare. Some are mild medical problems, while others are moderate or serious. Some are so serious that they may cause death. A few of the most common forms of anemia include the following.

IRON DEFICIENCY ANEMIA. Iron deficiency anemia is the most common form of anemia in the world. In the United States the condition primarily affects young children and women. About 240,000 children between the ages of one and two have the condition. About 3.3 million women of child-bearing age have iron deficiency anemia.

The onset (beginning) of iron deficiency anemia is gradual. There may be no symptoms at first. As the name suggests, iron deficiency anemia occurs when the body does not have enough iron to make all the red blood cells it needs. Red blood cells die off faster than they can be made by the body.

FOLIC ACID DEFICIENCY ANEMIA. Folic acid is a member of the vitamin B family. It is used in the production of new red blood cells. Some people do not get enough folic acid in their normal diet, so their bodies are unable to produce enough red blood cells. In other cases, the body may not be able to properly use the folic acid eaten.

Folic acid deficiency anemia occurs most often in infants and teenagers. Some important sources of folic acid are cheese, eggs, fish, green vegetables, meat, milk, and yeast. Smoking can also interfere with the body's ability to use folic acid.

VITAMIN B₁₂ DEFICIENCY ANEMIA. Like folic acid, vitamin B₁₂ is used to make red blood cells. The vitamin is found in meat and vegetables. Some symptoms of vitamin B₁₂ deficiency anemia are loss of muscle control, loss of feeling in the arms and legs, soreness of the tongue, and weight loss.

The most common form of vitamin B₁₂ deficiency anemia is called pernicious anemia. People between the ages of fifty and sixty are at highest risk for pernicious anemia. Some conditions that can lead to pernicious anemia are eating disorders (see anorexia nervosa and bulimia entries), poor nutrition, diabetes mellitus (pronounced DI-uh-BEE-teez MEH-luh-tuss; see diabetes mellitus entry), stomach problems, and thyroid disease.

HEMOLYTIC ANEMIA. Hemolytic (pronounced HEE-muh-lit-ik) anemia occurs when red blood cells are destroyed faster than they are made. In some cases, an infection can cause this problem. In other cases, the body's own immune system destroys the red blood cells. Some symptoms of hemolytic anemia include pain, shock, gallstones, an enlarged spleen, and other serious health problems.

An illustration of normal red blood cells (left) and those in three different types of anemia (from left), iron deficiency anemia, megaloblastic anemia, and sickle cell anemia. (Reproduced by permission of

John Bavosi and Custom Medical Stock Photo

)

THALASSEMIAS. Thalassemias (pronounced thal-uh-SEE-mee-uhs) are caused by the body's inability to manufacture enough red blood cells. The condition is a genetic disorder, meaning that parents who have a gene for the condition may pass it to their children. Genes are chemical units in the body that tell cells what functions to perform. In people who have defective thalassemia genes, cells have lost the instructions needed to produce red blood cells.

AUTOIMMUNE HEMOLYTIC ANEMIAS. An autoimmune disorder is one in which a person's immune system attacks its own body. The normal function of the immune system is to protect the body against foreign invaders, such as bacteria and viruses. But the immune system can sometimes become confused. It thinks that parts of the body are a foreign invader. In the case of autoimmune hemolytic anemias, the immune system attacks red blood cells, killing them just as it would destroy bacteria or viruses.

SICKLE CELL ANEMIA. Sickle cell anemia (see sickle cell anemia entry) is a genetic disorder. Cells receive genes that give them the wrong instructions for making red blood cells. Red blood cells are normally shaped like plump doughnuts. In sickle cell anemia, the cells are curved with sharp points. These cells easily stick to each other. They also stick to the walls of blood vessels. Clumps of sickled red blood cells can collect in a vein or artery and block it. This condition can cause pain, weakness, and, in extreme cases, death.

APLASTIC ANEMIA. Aplastic anemia is a serious form of anemia that can lead to death. The body makes too few of all kinds of blood cells: red blood cells, white blood cells, and platelets (pronounced PLATE-lits). Platelets are blood cells that help blood to clot. Aplastic anemia may be caused by a recent severe illness, long-term exposure to industrial chemicals, and the use of certain types of medication.

CAUSES

Anemia is caused primarily by one of three conditions. The first is bleeding. Bleeding results in the loss of red blood cells from the body. The second condition is a decreased rate of red blood cell production. Red blood cells are not produced as fast as they die off. The third condition is an increased rate of red blood cell destruction. Red blood cells die off faster than they can be replaced by the body.

Magnified red blood cells floating inside a blood vessel. (Photograph by

Dennis Kunkel

. Reproduced by permission of

Phototake NYC

.)

Of these factors, bleeding is the most common cause of anemia. Bleeding can be a chronic or acute problem. A chronic problem is one that lasts for a long period of time. An acute problem is one that comes on suddenly and is quite severe. Some common causes of chronic bleeding include:

• Cancer (see cancer entry)
• Gastrointestinal (digestive system) tumors
• Other diseases and disorders of the digestive system
• Heavy menstrual flow
• Hemorrhoids
• Nosebleeds
• Stomach ulcers (see ulcer entry)
• Long-term alcohol abuse (see alcoholism entry)

Acute blood loss is usually the result of:

• Childbirth
• Injury
• A ruptured blood vessel
• Surgery

SYMPTOMS

Some common symptoms of mild anemia include weakness, fatigue, and a "run-down" feeling. Other signs include pale skin and a lack of color in the creases of the palm, gums, nail beds or lining of the eyelids. Someone who is weak, tires easily, is often out of breath, and feels faint or dizzy may have severe anemia. Other symptoms of anemia include:

• Chest pain, often accompanied by a choking sensation
• A strong desire to eat ice, paint, or dirt
• Headache
• Loss of memory or the ability to concentrate
• Inflammation of the tongue or mouth
• Insomnia (inability to sleep)
• Irregular heartbeat
• Loss of appetite
• Nails that are dry, brittle, or ridged
• Rapid breathing
• Sores in the mouth, throat, or rectum
• Sweating
• Swelling of the hands and feet
• Excessive thirst
• Ringing in the ears
• Unexplained bleeding or bruising

Additional symptoms related to pernicious anemia include:

• Problems with movement or balance
• Tingling in the hands and feet
• Confusion, depression, and memory loss

DIAGNOSIS

The first step in diagnosing anemia is usually to take a medical history. Since some forms of anemia are inherited, a doctor will especially want to discover if the condition has occurred with other members of the family.

The best way of diagnosing anemia is with a blood test. A sample of the patient's blood is taken with a needle. The sample is then studied under a microscope. The number, size, and shape of red blood cells can then be determined. This information tells whether the patient has anemia and, if so, what kind.

TREATMENT

Treatment differs for each type of anemia. Iron deficiency, folic acid deficiency, and vitamin B₁₂ deficiency anemias are all nutritional problems. That is, the patient is not getting enough of certain essential nutrients through his or her diet. Problems of this kind can often be solved with nutritional supplements. The patient may need to take vitamin or mineral supplements that provide the missing nutrient. Patients should also be sure to eat foods that contain the vitamins and minerals needed to prevent anemia, including:

• Almonds
• Broccoli
• Dried beans
• Dried fruits
• Enriched breads and cereals
• Lean red meat
• Liver
• Potatoes
• Rice
• Shellfish
• Tomatoes

More serious forms of anemia may require surgery. Bleeding ulcers and certain types of stomach disorders are examples of anemias that may be treated surgically. In some cases, blood transfusions may be required. People who have lost large numbers of red blood cells may require a transfusion in order to avoid serious complications of anemia.

The most extreme form of treatment in such cases is a bone marrow transplant. All blood cells are made in bone marrow. Marrow is a fatty tissue found in the center of bones. People whose bodies make too few red blood cells may need a bone marrow transplant. Marrow from a healthy person is injected into the patient's bones. If successful, the healthy marrow begins producing red blood cells.

There is no cure for sickle cell anemia, autoimmune hemolytic anemia, and some other forms of anemia, therefore, treatment for these forms of anemia has two goals. First, steps should be taken to avoid complications. For example, a person with sickle cell anemia may require immunizations (shots) to protect against influenza, pneumonia, and other infectious diseases. Second, efforts should be made to relieve symptoms as much as possible. People with hemolytic anemia, for example, may be given shots of corticosteroids (pronounced kor-tih-ko-STIHR-oids), which help reduce inflammation and swelling that often accompany this condition.

Alternative Treatment

Practitioners often follow traditional medical treatments in dealing with anemia. That is, they may recommend nutritional supplements to replace lost iron or to improve general health. Certain iron-rich herbs may also be recommended. These herbs include yellow dock root, dandelion, parsley, and nettle.

Herbs may also be suggested to improve digestion. Improved digestion ensures that iron in foods is more likely to be absorbed by the body. Some herbs recommended for this purpose include gentian, anise, caraway, cumin, linden, and licorice.

Traditional Chinese treatments for anemia include:

• Acupuncture, which is a therapy technique where fine needles puncture the body, to improve the health of the spleen
• Asian ginseng, to restore energy
• Dong quai, an herb used to control heavy menstrual bleeding
• A mixture of dong quai and Chinese foxglove, to clear a pale complexion

PROGNOSIS

Prognosis differs for various kinds of anemia. Deficiency anemias usually improve after three to six weeks of treatment. Patients should continue taking supplements for six months to make sure the body has enough iron. Periodic tests may be necessary to make sure that the anemia has not returned.

Pernicious anemia cannot be cured. However, its symptoms can be treated with regular shots of vitamin B₁₂. This treatment usually works very quickly, often within a matter of minutes. There is also no cure for sickle cell anemia. Many patients, however, are able to lead reasonably normal lives with proper treatment.

Aplastic anemia can sometimes be cured with a bone marrow transplant. Thalassemias usually require no treatment. People are able to live normal lives with all but the most severe forms of the disease.

PREVENTION

Inherited forms of anemia cannot be prevented. Parents can often find out if they carry the genes for anemia. With this information, they can decide if they want to have children and pass those genes on to them.

Eating a well-balanced diet and avoiding excessive amounts of alcohol is a simple method to protect against deficiency forms of anemia. To be safe, a person can take nutritional supplements to ensure that he or she is getting enough iron.

Some methods of preventing specific types of anemia include:

• Avoiding lengthy exposure to industrial chemicals and drugs known to cause aplastic anemia
• Not taking medications or eating foods that may cause hemolytic anemia
• Receiving regular B₁₂ shots to prevent pernicious anemia

See also: Sickle cell anemia.

FOR MORE INFORMATION

Books

Beshore, George W., ed. Sickle Cell Anemia. New York: Franklin Watts, 1994.

Uthman, Ed. Understanding Anemia. Jackson: University Press of Mississippi, 1998.

Organizations

Aplastic Anemia Foundation of America. P.O. Box 613, Annapolis, MD 21404. (800) 747–2620. http://www.aplastic.org.