Posted on 06 Dec 2010 04:37
Anemia is a condition in which your blood does not carry enough oxygen to the rest of your body because of a shortage of health red blood cells. This is most commonly caused by a shortage of iron in the body, which is needed to make hemoglobin. The iron containing protein that gives blood the its red color, hemoglobin is the actual component of the blood cells which carries the oxygen.
Causes of Anemia
Anemia causes can be broadly separated into iron deficiency anemia, vitamin deficiency anemia and anemia of chronic disease.
Common causes of low iron are heavy periods in females, pregnancy, ulcers, colon polyps, colon cancer, and a diet deficient in iron. Inadequate folic acid or vitamin B12 can also cause anemia. Inherited blood blood disorders that cause anemia include sickle cell anemia and thalassemia. Other conditions which can result in anemia are diabetes cancer, inflammatory bowel disease, kidney disease, heart disease, hepatitis C, HIV/AIDS, and rheumatoid arthritis.
Common Anemia Symptoms
Anemia can make you feel weak, cold, dizzy and irritable. It can cause shortness of breath, making you feel out of breath from performing routine activities. Exercise may difficult to tolerate. Pale skin, chest pain, cold hands and feet, irregular heartbeat, and brittle nails may also be symptoms of anemia. Although many think it is a myth, a desire to eat ice may also be a sign of anemia, along with the desire to eat many other odd items such as paper or clay. It is unkown exactly why these unusual cravings occur. However, ice is the most common craving. 1,2
Having many of the symptoms that are associated with anemia is not proof that you are anemic. Many of these symptoms are general in nature and could be associated with many other disorders. Mild anemia, such as caused by low iron or vitamins, is easily treated but other types may be long-lasting, severe, and life-threatening if not diagnosed and properly treated.
Your doctor will diagnose anemia based on your medical history, a physical exam, and the results from tests and procedures, such as a complete blood count (CBC). Once your doctor knows the cause and severity of the condition, he or she can create a treatment plan for you.
Mild to moderate iron-deficiency anemia may have no signs or symptoms. Thus, you may not know you have it unless your doctor discovers it from a screening test or while checking for other problems.
Primary care doctors often diagnose and treat iron-deficiency anemia. These doctors include pediatricians, family doctors, gynecologists/obstetricians, and internal medicine specialists. A hematologist (a blood disease specialist), a gastroenterologist (a digestive system specialist), and other specialists also may help treat iron-deficiency anemia.
To learn about your medical history, your doctor will ask about your signs and symptoms and any past problems you’ve had with anemia or low iron.
Your doctor also may ask about your diet and whether you’re taking any medicines. If you're a woman, your doctor may ask whether you could be pregnant.
Your doctor will do a physical exam to look for signs of iron-deficiency anemia. He or she may:
- Look at your skin, gums, and nail beds to see whether they're pale or yellowish
- Listen to your heart for a rapid or irregular heartbeat
- Listen to your lungs for rapid or uneven breathing
- Feel your abdomen to check the size of your liver and spleen
- Do a pelvic and rectal exam to check for internal bleeding
Diagnostic Tests and Procedures
A number of tests and procedures are used to diagnose iron-deficiency anemia. They can help confirm a diagnosis, look for a cause, and find out how severe the condition is.
Complete Blood Count (CBC)
Often, the first test used to diagnose anemia is a complete blood count (CBC). The CBC measures many different parts of your blood.
This test checks your hemoglobin and hematocrit (hee-MAT-oh-crit) levels. Hemoglobin is the iron-rich protein in red blood cells that carries oxygen to the body. Hematocrit is a measure of how much space red blood cells take up in your blood. A low level of hemoglobin or hematocrit is a sign of anemia.
The normal range of these levels varies in certain racial and ethnic populations. Your doctor can explain your test results to you.
The CBC also checks the number of red blood cells, white blood cells, and platelets in your blood. Abnormal results may be a sign of infection, a blood disorder, or another condition.
Finally, the CBC looks at mean corpuscular (kor-PUS-kyu-lar) volume (MCV). MCV is a measure of the average size of your red blood cells. The results may be a clue as to the cause of your anemia. In iron-deficiency anemia, for example, red blood cells usually are smaller than normal.
Other Blood Tests
If the CBC results confirm you have anemia, you may need other blood tests to find out what's causing the condition, how severe it is, and the best way to treat it.
A reticulocyte (re-TIK-u-lo-site) count measures the number of young red blood cells in your blood. The test shows whether your bone marrow is making red blood cells at the correct rate.
Your doctor also may order a peripheral smear. For this test, a sample of your blood is examined under a microscope. In people who have iron-deficiency anemia, the red blood cells will look smaller and paler than normal.
Your doctor may recommend tests to measure iron levels in your blood and body. These tests can show how much iron has been used from your body's stored iron. These tests include:
- Serum iron. This test measures the amount of iron in your blood. The level of iron in your blood may be normal even if the total amount of iron in your body is low. For this reason, other iron tests also are done.
- Serum ferritin. Ferritin is a protein that helps store iron in your body. A measure of this protein helps your doctor find out how much of your body's stored iron has been used up.
- Transferrin level, or total iron-binding capacity. Transferrin is a protein that carries iron in your blood. Total iron-binding capacity measures how much of the transferrin in your blood isn't carrying iron. If you have iron-deficiency anemia, you'll have a high level of transferrin that has no iron.
Your doctor also may recommend tests to check your hormone levels, especially your thyroid hormone. You also may have a blood test for a chemical called erythrocyte protoporphyrin. This chemical is a building block for hemoglobin.
Tests and Procedures for Gastrointestinal Blood Loss
To check whether internal bleeding is causing your iron-deficiency anemia, your doctor may suggest a fecal occult blood test. This test looks for blood in the stools and can detect bleeding in the intestines.
If the test finds blood, you may have other tests and procedures to find the exact spot of the bleeding. These tests and procedures may look for bleeding in the stomach, upper intestines, and colon or pelvic organs. 4
Prognosis depends on the severity of the anemia and the treatment that is needed to reverse it. For blood disorders requiring blood transfusion the blood cells are replaced directly so symptoms should immediately subside. With other types that are treated through erythropoiesis-stimulating agents (ESAS), iron supplements, or vitamin supplements the body begins to manufacture new red blood cells in 5-7 days and hemoglobin levels rise within 2-3 weeks after treatment is begun. For more information visit National Anemia Action Council FAQ. 2
Iron Deficiency and Anemia
Blood loss, poor diet, or an inability to absorb enough iron from foods can cause iron Iron-deficiency anemia, a common and easily treated anemia condition. This condition develops over time, as your body runs out of stored iron causing less blood cells to be manufactured. Severe iron-deficiency anemia can lead to heart problems, infections, problems with growth and development in children, and other complications.
People at highest risk for iron-deficiency anemia include infants and young children, women, and adults who have internal bleeding. On rare occasions, severe iron-deficiency anemia may require treatment in a hospital, blood transfusions, iron injections, or intravenous iron therapy.
Blood Loss and Iron-Deficiency Anemia
When you lose blood, you lose iron. If you don’t have enough iron stored in your body to make up for the iron loss, you’ll develop iron-deficiency anemia.
In women, low iron levels may be due to blood loss from long or heavy menstrual periods or bleeding fibroids in the uterus. Blood loss that occurs during childbirth is another cause for low iron levels in women.
Internal bleeding (bleeding inside the body) also may lead to iron-deficiency anemia. This type of blood loss isn’t always obvious, and it may occur slowly. Some causes of internal bleeding are:
- A bleeding ulcer, colon polyp, or colon cancer
- Regular use of aspirin or other pain medicines, such as nonsteroidal anti-inflammatory drugs (for example, ibuprofen and naproxen)
- Urinary tract bleeding
Blood loss from severe injuries, surgery, or frequent blood drawings also can cause iron-deficiency anemia.
The best sources of iron are meat, poultry, fish, eggs, and iron-fortified foods (foods that have iron added). If you don’t eat these foods regularly, or if you don’t take an iron supplement, you’re more likely to get iron-deficiency anemia.
Vegetarian diets can provide enough iron if the right foods are eaten. For example, good nonmeat sources of iron include spinach and other dark green leafy vegetables, certain types of beans, dried fruits, and iron-fortified breads and cereals.
During some stages of life, such as pregnancy and childhood, it may be hard to get enough iron in your diet. This is because your need for iron increases during these times of growth and development.
Inability To Absorb Enough Iron
Even if there's enough iron in your diet, your body may not be able to absorb it. This may be due to intestinal surgery or diseases of the intestine, such as Crohn’s disease or celiac disease. Prescription medicines that reduce acid in the stomach also can interfere with iron absorption.
Infants and Young Children
Infants and young children need a lot of iron to grow and develop. The iron that full-term infants have stored in their bodies is used up in the first 4 to 6 months of life.
Premature and low-birth-weight babies are at even greater risk for iron-deficiency anemia. These babies don’t have as much iron stored in their bodies as other babies do.
Iron-fortified foods for babies or iron supplements, when used properly, can help prevent iron-deficiency anemia in infants and young children. Talk to your child's doctor about your child's diet.
Young children who drink large amounts of cow's milk may be at risk for iron-deficiency anemia. Milk is low in iron, and too much milk may take the place of iron-rich foods in the diet. Too much milk also may prevent children’s bodies from absorbing iron from other foods.
Children who have lead in their blood also may be at risk for iron-deficiency anemia. Lead can interfere with the body’s ability to make hemoglobin. Lead may get into the body from breathing in lead dust, eating lead in paint or soil, or drinking water that contains lead.
Women of childbearing age are at increased risk for iron-deficiency anemia because of blood loss during their monthly periods. About 1 in 5 women of childbearing age has iron-deficiency anemia.
Pregnant women also are at higher risk for the condition because they need twice as much iron as usual. The extra iron is needed for increased blood volume and for the fetus' growth.
About half of all pregnant women develop iron-deficiency anemia. The condition can increase a pregnant woman's risk for a premature or low-birth-weight baby.
Adults Who Have Internal Bleeding
Adults who have internal bleeding, such as intestinal bleeding, can develop iron-deficiency anemia due to blood loss. Certain conditions, such as colon cancer and bleeding ulcers, can cause blood loss. Certain medicines, such as aspirin, also can cause internal bleeding.
Other At-Risk Groups
People who get kidney dialysis treatment may develop iron-deficiency anemia. This is because blood is lost during dialysis. Also, the kidneys are no longer able to make enough of a hormone needed to make red blood cells.
Certain Eating Patterns
Certain eating patterns or habits can put you at higher risk for iron-deficiency anemia. This can happen because of:
- Following a diet that excludes meat and fish, which are the best sources of iron. However, vegetarian diets can provide enough iron if the right foods are eaten. For example, good nonmeat sources of iron include spinach and other dark green leafy vegetables, certain types of beans, dried fruits, and iron-fortified breads and cereals.
- Eating poorly due to money, social, health, or other problems.
- Following a very low-fat diet over a long period. Some higher fat foods, like meat, are some of the best sources of iron.
- Following a high-fiber diet. Large amounts of fiber can slow the absorption of iron.
Signs and Symptoms of Iron-Deficiency Anemia
The signs and symptoms of iron-deficiency anemia are the same as all anemia and include all the symptoms given above. The symptoms depend on how serious the condition is. Mild to moderate iron-deficiency anemia may have no signs or symptoms. When signs and symptoms do occur, they can range from mild to severe. Many of the signs and symptoms of iron-deficiency anemia apply to all types of anemia.
Treatment for Iron-Deficiency Anemia
Treatment for iron-deficiency anemia will depend on the cause and severity of the condition. Treatments may include dietary changes and supplements, medicines, and surgery. Severe iron-deficiency anemia may require treatment in a hospital, blood transfusions, iron injections, or intravenous (IV) iron therapy.
The goals of treating iron-deficiency anemia are to treat its underlying cause and restore normal levels of red blood cells, hemoglobin, and iron.
Dietary Changes and Supplements
The following sections cover some of the dietary changes that may be necessary for anemia. The dietary habits that treat iron-deficiency anemia will help to prevent it. Not that cow's milk is not recommended for infants because it is low in iron, among other reasons.
If you have iron-deficiency anemia you may need iron supplements to build up your iron levels as quickly as possible. Iron supplements can correct low iron levels within months. Supplements come in pill form or in drops for children.
Large amounts of iron can be harmful. Thus, you should take iron supplements only as your doctor prescribes. Keep iron supplements out of reach from children. This will prevent them from taking an overdose of iron.
Iron supplements can cause side effects, such as dark stools, stomach irritation, and heartburn. Iron also can cause constipation, so your doctor may suggest that you use a stool softener.
Your doctor may advise you to eat more foods that are rich in iron. The best source of iron is red meat, especially beef and liver. Chicken, turkey, pork, fish, and shellfish also are good sources of iron. The body tends to absorb the iron from meat better than iron in other foods. However, other foods also can help you raise your iron levels.
Nonmeat foods that are good sources of iron include:
- Spinach and other dark green leafy vegetables
- Peanuts, peanut butter, and almonds
- Peas; lentils; and white, red, and baked beans
- Dried fruits, such as raisins, apricots, and peaches
- Prune juice
Iron is added to some foods, such as cereal, bread, and pasta. You can look at the Nutrition Facts label on a food to find out how much iron it contains. The amount is given as a percentage of the total amount of iron you need every day. 4 The following is a more complete overview of dietary iron and iron-containing foods.
What is Iron?
Iron, one of the most abundant metals on Earth, is essential to most life forms and to normal human physiology. Iron is an integral part of many proteins and enzymes that maintain good health. In humans, iron is an essential component of proteins involved in oxygen transport. It is also essential for the regulation of cell growth and differentiation. A deficiency of iron limits oxygen delivery to cells, resulting in fatigue, poor work performance, and decreased immunity. On the other hand, excess amounts of iron can result in toxicity and even death.
Almost two-thirds of iron in the body is found in hemoglobin, the protein in red blood cells that carries oxygen to tissues. Smaller amounts of iron are found in myoglobin, a protein that helps supply oxygen to muscle, and in enzymes that assist biochemical reactions. Iron is also found in proteins that store iron for future needs and that transport iron in blood. Iron stores are regulated by intestinal iron absorption. 3
What foods provide iron?
There are two forms of dietary iron: heme and nonheme. Heme iron is derived from hemoglobin, the protein in red blood cells that delivers oxygen to cells. Heme iron is found in animal foods that originally contained hemoglobin, such as red meats, fish, and poultry. Iron in plant foods such as lentils and beans is arranged in a chemical structure called nonheme iron. This is the form of iron added to iron-enriched and iron-fortified foods. Heme iron is absorbed better than nonheme iron, but most dietary iron is nonheme iron. A variety of heme and nonheme sources of iron are listed in Tables 1 and 2.
Table One: Good Food Sources of Heme Iron
|Food||Mg. per serv.||% DV*|
|Chicken liver, cooked, 3½ oz.||12.8||70|
|Oysters, breaded and fried, 6 pieces||4.5||25|
|Beef, chuck, lean only, braised, 3 oz.||3.2||20|
|Clams, breaded, fried, ¾ cup||3.0||15|
|Beef, tenderloin, roasted, 3 oz.||3.0||15|
|Turkey, dark meat, roasted, 3½ oz.||2.3||10|
|Beef, eye of round, roasted, 3 oz.||2.2||10|
|Turkey, light meat, roasted, 3½ oz.||1.6||8|
|Chicken, leg, meat only, roasted, 3½ oz.||1.3||6|
|Tuna, fresh bluefin, cooked, 3 oz.||1.1||6|
|Chicken, breast, roasted, 3 oz.||1.1||6|
|Halibut, cooked, dry heat, 3 oz.||0.9||6|
|Crab, blue crab, cooked, 3 oz.||0.8||4|
|Pork, loin, broiled, 3 oz.||0.8||4|
|Tuna, white, canned in water, 3 oz.||0.8||4|
|Shrimp, mixed species, cooked, 4 lrg||0.7||4|
Table 2: Good Food Sources of Nonheme Iron
|Food||Mg. per serving||% DV*|
|Ready-to-eat cereal, 100% iron fortified, ¾ cup||18.0||100|
|Oatmeal, instant, fortified, prepared with water, 1 cup||10.0||60|
|Soybeans, mature, boiled, 1 cup||8.8||50|
|Lentils, boiled, 1 cup||6.6||35|
|Beans, kidney, mature, boiled, 1 cup||5.2||25|
|Beans, lima, large, mature, boiled, 1 cup||4.5||25|
|Beans, navy, mature, boiled, 1 cup||4.5||25|
|Ready-to-eat cereal, 25% iron fortified, ¾ cup||4.5||25|
|Beans, black, mature, boiled, 1 cup||3.6||20|
|Beans, pinto, mature, boiled, 1 cup||3.6||20|
|Molasses, blackstrap, 1 tablespoon||3.5||20|
|Tofu, raw, firm, ½ cup||3.4||20|
|Spinach, boiled, drained, ½ cup||3.2||20|
|Spinach, canned, drained solids ½ cup||2.5||10|
|Black-eyed peas (cowpeas), boiled, 1 cup||1.8||10|
|Spinach, frozen, chopped, boiled ½ cup||1.9||10|
|Grits, white, enriched, quick, prepared with water, 1 cup||1.5||8|
|Raisins, seedless, packed, ½ cup||1.5||8|
|Whole wheat bread, 1 slice||0.9||6|
|White bread, enriched, 1 slice||0.9||6|
*DV = Daily Value. DVs are reference numbers developed by the Food and Drug Administration (FDA) to help consumers determine if a food contains a lot or a little of a specific nutrient. The FDA requires all food labels to include the percent DV (%DV) for iron. The percent DV tells you what percent of the DV is provided in one serving. The DV for iron is 18 milligrams (mg). A food providing 5% of the DV or less is a low source while a food that provides 10-19% of the DV is a good source. A food that provides 20% or more of the DV is high in that nutrient. It is important to remember that foods that provide lower percentages of the DV also contribute to a healthful diet. For foods not listed in this table, please refer to the U.S. Department of Agriculture's Nutrient Database Web site: http://www.nal.usda.gov/fnic/cgi-bin/nut_search.pl. 3
Vitamin C helps the body absorb iron. Good sources of vitamin C are fruits and vegetables, especially guava, red sweet pepper, kiwi, oranges and orange juice, green pepper, and grapefruit juice.
If you're taking medicines, ask your doctor or pharmacist whether you can eat grapefruit or drink grapefruit juice. This fruit can affect the strength of a few medicines and how well they work.
Other fruits rich in vitamin C are strawberries, cantaloupe, papaya, pineapple, and mango. Vegetables high in vitamin C include vegetable and tomato juices, Brussels sprouts, kohlrabi, broccoli, sweet potato, cauliflower, and kale. Fresh and frozen fruits, vegetables, and juices usually have more vitamin C than canned ones.
Treatment To Stop Bleeding
If blood loss is causing iron-deficiency anemia, treatment will depend on the cause of the bleeding. For example, if you have a bleeding ulcer, your doctor may prescribe antibiotics and other medicines to treat the ulcer.
If your blood loss is due to a polyp or a cancerous tumor in your intestine, you may need surgery to remove the growth.
If blood loss is due to heavy menstrual flow, your doctor may prescribe oral contraceptives to help reduce your monthly blood flow. In some cases, surgery may be advised.
Treatments for Severe Iron-Deficiency Anemia
If your iron-deficiency anemia is severe, you may get a transfusion of red blood cells. A blood transfusion is a safe, common procedure in which blood is given to you through an IV line in one of your blood vessels. Transfusions require careful matching of donated blood with the recipient's blood.
A transfusion of red blood cells will treat your anemia right away. The red blood cells also give a source of iron that your body can reuse. However, transfusions are only a short-term treatment. Your doctor will need to find and treat the cause of your anemia.
Iron also may be injected into a muscle or through an IV tube into a vein. However, IV iron therapy presents some safety concerns. It must be done in a hospital or clinical setting by experienced staff. This therapy usually is given to people who need iron long-term but can’t take iron supplements by mouth or who need to be treated for iron-deficiency anemia right away. 4
Various Diseases Associated with Anemia
Below will be described a number of chronic diseases and conditions, how they cause anemia, their diagnoses and treatment. These include anemia of inflammation and chronic disease (AI/ACD), plastic Anemia and MDS,
Anemia of inflammation and chronic disease (AI/ACD)
A number of chronic diseases can cause anemia for different reasons. These types of anemia can be easily confused with iron-deficiency anemia because in both forms of anemia, levels of iron circulating in the blood are low. Circulating iron is necessary for red blood cell production. Low blood iron levels occur in iron-deficiency anemia because levels of iron stored in the body’s tissues are depleted. In AI/ACD, however, iron stores are normal or high. Low blood levels occur in AI/ACD, despite normal iron stores, because inflammatory and chronic diseases interfere with the body’s ability to use stored iron and absorb iron from the diet. Certain treatments for chronic diseases may also impair RBC production and contribute to AI/ACD. AI/ACD is the second most common form of anemia, after iron-deficiency anemia, but it is rarely severe.
Infectious and inflammatory diseases and Anemia
As part of the immune response that occurs with infection and noninfectious inflammatory diseases, cells of the immune system release proteins called cytokines. These proteins help heal and defend the body against infection. But they can also affect normal body functions. In AI/ACD, immune cytokines interfere with the body’s ability to absorb and use iron. Cytokines may also interfere with the production and normal activity of erythropoietin (EPO), a hormone made by the kidneys that stimulates bone marrow to produce RBCs.
Infectious diseases that cause AI/ACD include tuberculosis, HIV, endocarditis—infection in the heart—and osteomyelitis, a bone infection. Sometimes acute infections—those that develop quickly and may not last long—can also cause AI/ACD.
Inflammatory diseases that can lead to AI/ACD include rheumatoid arthritis, lupus, diabetes, heart failure, degenerative joint disease, and inflammatory bowel disease (IBD). IBD, including Crohn’s disease, can also cause iron deficiency due to poor absorption of iron by the diseased intestine and bleeding from the gastrointestinal tract.
Kidney disease and Anemia
People with kidney disease can develop anemia for several different reasons. For one, diseased kidneys often fail to make enough EPO. In addition, kidney disease results in abnormal absorption and use of iron, which is typical of AI/ACD. Because anemia worsens as kidney disease advances, nearly everyone with end-stage kidney disease has anemia.
People with kidney failure can also develop iron deficiency due to blood loss during hemodialysis, a procedure that removes blood from an artery, purifies it, and returns it to a vein, thereby doing the job that the kidneys no longer can. Low levels of iron and of folic acid—another nutrient required for normal RBC production—may also contribute to anemia in people with kidney disease.
Cancer and Anemia
AI/ACD can occur with certain types of cancer, including Hodgkin’s disease, non-Hodgkin’s lymphoma, and breast cancer. Like chronic inflammatory disorders and infections, these types of cancer cause inflammatory cytokines to be released in the body. The anemia of AI/ACD can also be made worse by cancer chemotherapy and radiation treatments that damage the bone marrow—where RBCs are produced—and by the cancer’s invasion of bone marrow.
What are the symptoms of AI/ACD?
AI/ACD typically develops slowly and, because it is usually mild, may cause few or no symptoms. Or its symptoms may be masked by the symptoms of the underlying disease. However as above it can cause or contribute to
- low energy and listlessness
- pale skin
- fast heartbeat
- shortness of breath
- exercise intolerance
How is AI/ACD diagnosed?
Health care providers can test people with chronic illnesses for AI/ACD during their regular appointments. A complete blood count (CBC)—a laboratory test performed on a sample of a patient’s blood—can reveal anemia by determining the hematocrit level, which reflects the number of RBCs in the blood. A CBC also measures the level of blood hemoglobin. Low hematocrit and hemoglobin levels indicate anemia. Blood tests can also show low iron levels in the blood but normal measures of iron stores in the body—a hallmark of AI/ACD.
How is AI/ACD treated?
AI/ACD often is not treated separately from the condition with which it occurs. In general, doctors focus on treating the underlying illness. If this treatment is successful, the anemia usually resolves. For example, antibiotics prescribed for infection and anti-inflammatory drugs prescribed for rheumatoid arthritis or IBD can cause the anemia of AI/ACD to disappear. However, AI/ACD is increasingly being viewed as a medical condition that merits direct treatment.
For people with cancer or kidney disease who have low levels of EPO, a synthetic form of this normal hormone may be prescribed. People with kidney disease and AI/ACD may also be advised to take vitamin B12 and folic acid supplements. If iron deficiency has a role in causing the anemia, iron supplements may be given.5
Aplastic Anemia and MDS
Aplastic anemia and myelodysplastic syndromes (MDS) are rare and serious disorders that affect the bone marrow and blood.
In both disorders, bone marrow doesn’t produce enough healthy red or white blood cells or platelets. Red blood cells contain hemoglobin, an iron-rich protein that gives blood its red color and carries oxygen from the lungs to the tissues of the body. White blood cells help fight infection. Too few functioning red and white blood cells can lead to fatigue and infection. Platelets are cells that help blood clot. Too few platelets can lead to spontaneous or uncontrolled bleeding.
Anemia most often describes a condition in which a person has too few red blood cells or cells that do not carry enough hemoglobin. In aplastic anemia, however, normal production of all blood cells—red cells, white cells, and platelets—slows or stops. Blood cell production declines because bone marrow stem cells—the cells that give rise to all three types of mature blood cells—are damaged. The number of stem cells also declines because they are unable to replicate themselves. Although production of mature blood cells is seriously impaired in aplastic anemia, the few blood cells that mature and enter the bloodstream are normal.
Aplastic anemia most often affects children and young adults. Between 500 and 1,000 people in the United States develop aplastic anemia each year.
In MDS, a shortage of bone marrow stem cells usually doesn’t occur, as it does in aplastic anemia. But the stem cells are defective and do not mature normally. Progenitor cells and immature blood cells are deformed and fail to develop into healthy, mature red or white blood cells or platelets. These cells often die in the bone marrow. Many of the blood cells that do enter the bloodstream don’t survive or function normally.
Some forms of MDS are prone to develop into leukemia, an aggressive blood cancer. Between 7,000 and 12,000 people, mostly older adults, develop MDS each year.
Blood Cell Production
All three types of blood cells begin as unspecialized stem cells. Stem cells divide and produce more stem cells or can evolve through a series of stages into mature, specialized blood cells of any type. Early in the maturation process, “progenitor” cells emerge from stem cells. Unlike stem cells, progenitor cells are committed to develop into only one blood cell type and evolve into mature red or white blood cells or platelets.
What causes Aplastic anemia and MDS?
Although the cause of aplastic anemia or MDS usually can’t be determined, the diseases may be triggered by exposure to
- radiation therapy
- high levels of ionizing radiation—the type produced by high power x-ray machines and in nuclear power plants
- benzene, a chemical used in some manufacturing processes
- toxic chemicals found in some pesticides
- certain viral infections
In most cases of aplastic anemia, these or other unknown triggers provoke the body’s own immune system to destroy the bone marrow stem cells. Certain rare inherited disorders can also lead to aplastic anemia and uncommon forms of MDS seen in children.
What are the symptoms of Aplastic anemia and MDS?
Symptoms vary depending on the individual and the severity and type of disease. Some are similar to all anemia conditions but some are particular. Symptoms may include
- tiredness, or fatigue
- excessive bleeding
- pinpoint red spots on the skin caused by bleeding from small blood vessels
- easy bruising
- frequent infections
- pale skin
- shortness of breath
Because many of these symptoms resemble those of other illnesses, a professional evaluation from a specialist is important. MDS often does not cause symptoms at first and may be discovered through a routine blood test.
How are aplastic anemia and MDS diagnosed?
In addition to a medical history and physical exam, doctors use blood tests and a bone marrow biopsy to diagnose aplastic anemia or MDS. *
Blood tests. A complete blood count (CBC) is usually the first test a doctor uses to detect aplastic anemia or MDS. This test measures the number of red blood cells, white blood cells, and platelets in the blood. It also looks at the amount of hemoglobin in the red blood cells. Lower-than-normal quantities of one or more blood cell types may suggest aplastic anemia or MDS.
In another test called a peripheral blood smear, the doctor examines a sample of blood for unusual changes in the size, shape, and appearance of the blood cells. These cells usually appear normal in aplastic anemia but may be abnormal in MDS.
Biopsy. A bone marrow biopsy is needed to confirm the diagnosis of aplastic anemia or MDS. This test usually involves removing a small sample of bone marrow by inserting a needle into the hip bone. A doctor then examines the bone marrow for the number and type of blood progenitor cells and for the presence of abnormal cells.
How are aplastic anemia and MDS treated?
Aplastic Anemia Treatment
People with mild or moderate aplastic anemia may not need treatment at first. However, people with severe aplastic anemia need immediate medical treatment to prevent or reverse complications from very low blood cell levels.
Blood transfusions. Transfusions of red blood cells or platelets, in which healthy cells from a donor with the same blood type are injected into a patient’s vein, can raise blood cell counts and relieve symptoms. But transfusions are not a cure.
Most people with aplastic anemia require repeated transfusions, which can lead to complications. Over time, the body may develop antibodies that damage or destroy donor blood cells. And iron from transfused red blood cells can build up in the body and damage organs unless the excess iron is removed with drugs called iron chelators.
Stem cell transplant. Stem cell transplants, which replace damaged stem cells in bone marrow with healthy stem cells from a donor’s blood or bone marrow, can cure aplastic anemia. However, this form of treatment is usually limited to people younger than 40 to 50 with an available donor—usually a brother or sister—whose bone marrow cells are tested and found to “match” those of the patient.
Before the transplant, the patient’s own bone marrow cells are eliminated by chemotherapy and sometimes radiation. Doctors remove stem cells from the donor’s blood or bone marrow and freeze them for storage. After chemotherapy, the doctor gives the patient the thawed stem cells through a blood infusion. The stem cells then travel to the bone marrow where they re-establish and maintain normal blood cell production.
Stem cell transplants are usually reserved for people with severe aplastic anemia and are most successful in children and young adults with matched donors. Older adults are less able to tolerate the treatments used to prepare the body for transplant and are more likely to develop severe post-transplant complications.
Medications. Doctors often prescribe one or more medications that suppress the immune system and reduce damage to bone marrow cells. These drugs may allow the marrow to start making blood cells again and reduce or eliminate the need for transfusions. In some people, blood counts return to normal. These “immunosuppressive” drugs are the preferred form of treatment for older adults and for young patients who don’t have a matched stem cell donor.
Adjunct drug therapy may include erythropoietin (EPO), a man-made version of a natural hormone that stimulates the production of red blood cells, or granulocyte-colony stimulating factor (G-CSF), which stimulates white blood cell production. Antibiotics are often used if infections occur.
Stem cell transplants are not routinely performed for MDS because most people with MDS are older adults and thus ineligible for this form of treatment. For younger people with a matched sibling donor, however, a transplant may offer a cure. No other potential cures for MDS currently exist. Treatment options, which may be used alone or in combination, include the following:
Supportive care. Traditionally the first line of treatment, supportive care aims to manage the symptoms of the disease. This approach may include blood transfusions and drug therapy with EPO, G-CSF, and antibiotics.
Medications. Three recently developed drugs—azacitidine (Vidaza), lenalidomide (Revlimid), and decitabine (Dacogen)—may help the bone marrow function more normally, reducing the need for transfusions. Azacitidine and decitabine are used to treat all forms of MDS, while lenalidomide is used to treat only one specific type of MDS. Some people may also benefit from immunosuppressive drugs.
Chemotherapy. Chemotherapy is sometimes used in an effort to destroy defective blood progenitor cells in severe MDS and allow the few remaining normal blood stem cells to re-establish normal blood cell production. This approach is often not effective over the long term.
Experimental stem cell transplants. New techniques that use a less toxic pretransplant regimen are being developed. Since the regimen may be better tolerated by older adults, it may allow stem cell transplants to be more widely used as a treatment for MDS. 6
Erythropoiesis-Stimulating Agents (ESAs) for Anemia
ESAs are drugs manufactured under names such as Epogen, Procrit, and Aranesp. These drugs work by stimulating the bone marrow to produce red blood cells. ESAs are approved for the treatment of anemia (low red blood cells) resulting from chronic kidney failure, chemotherapy, certain treatments for Human Immunodeficiency Virus (HIV), and also to reduce the number of blood transfusions during and after certain major surgeries.
Erythropoiesis-Stimulating Agents are not without risks. ESAs can increase the risk of tumor growth and shorten survival in patients with cancer who use these products. Studies also show that ESAs can increase the risk of heart attack, heart failure, stroke or blood clots in patients who use these drugs for other conditions. 7
This page is provided by Ground Up Strength for information purposes only and should not take the place of professional medical advice. Although we have done our utmost to provide accurate and safe information, we are not medical professionals and the information on this page should not be taken as professional medical advice, or any other kind of medical advice.