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Anemias |
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Anemias DefinitionAnemia is a condition characterized by abnormally low levels of healthy red blood cells or hemoglobin (the component of red blood cells that delivers oxygen to tissues throughout the body). DescriptionThe tissues of the human body need a regular supply of oxygen to stay healthy. Red blood cells, which contain hemoglobin that allows them to deliver oxygen throughout the body, live for only about 120 days. When they die, the iron they contain is returned to the bone marrow and used to create new red blood cells. Anemia develops when heavy bleeding causes significant iron loss or when something happens to slow down the production of red blood cells or to increase the rate at which they are destroyed. Types of anemiaAnemia can be mild, moderate, or severe enough to lead to life-threatening complications. More than 400 different types of anemia have been identified. Many of them are rare. IRON DEFICIENCY ANEMIA. The onset of iron deficiency anemia is gradual and, at first, there may not be any symptoms. The deficiency begins when the body loses more iron than it derives from food and other sources. Because depleted iron stores cannot meet the red blood cell's needs, fewer red blood cells develop. In this early stage of anemia, the red blood cells look normal, but they are reduced in number. Then the body tries to compensate for the iron deficiency by producing more red blood cells, which are characteristically small in size. Symptoms develop at this stage. FOLIC ACID DEFICIENCY ANEMIA. Folic acid anemia is especially common in infants and teenagers. Although this condition usually results from a dietary deficiency, it is sometimes due to inability to absorb enough folic acid from such foods as:
![]() 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. (Illustration by John Bavosi, Custom Medical Stock Photo. Reproduced by permission.) Smoking raises the risk of developing this condition by interfering with the absorption of Vitamin C, which the body needs to absorb folic acid. Folic acid anemia can be a complication of pregnancy, when a woman's body needs eight times more folic acid than it does otherwise. VITAMIN B12 DEFICIENCY ANEMIA. Less common in this country than folic acid anemia, vitamin B12 deficiency anemia is another type of megaloblastic anemia that develops when the body doesn't absorb enough of this nutrient. Necessary for the creation of red blood cells, B12 is found in meat and vegetables. Large amounts of B12 are stored in the body, so this condition may not become apparent until as much as four years after B12 absorption stops or slows down. The resulting drop in red blood cell production can cause:
The most common form of B12 deficiency is pernicious anemia. Since most people who eat meat or eggs get enough B12 in their diets, a deficiency of this vitamin usually means that the body is not absorbing it properly. This can occur among people who have had intestinal surgery or among those who do not produce adequate amounts of intrinsic factor, a chemical secreted by the stomach lining that combines with B12 to help its absorption in the small intestine. Pernicious anemia usually strikes between the ages of 50-60. Eating disorders or an unbalanced diet increase the risk of developing pernicious anemia. So do:
VITAMIN C DEFICIENCY ANEMIA. A rare disorder that causes the bone marrow to manufacture abnormally small red blood cells, Vitamin C deficiency anemia results from a severe, long-standing dietary deficiency. HEMOLYTIC ANEMIA. Some people are born with hemolytic anemia. Some acquire this condition, in which infection or antibodies destroy red blood cells more rapidly than bone marrow can replace them. Hemolytic anemia can enlarge the spleen, accelerating the destruction of red blood cells (hemolysis). Other complications of hemolytic anemia include:
Key termsAplastic — Exhibiting incomplete or faulty development. Hemoglobin — An iron-containing pigment of red blood cells composed of four amino acid chains (alpha, beta, gamma, delta) that delivers oxygen from the lungs to the tissues of the body. Megaloblast — A large erythroblast (a red marrow cell that synthesizes hemoglobin). THALASSEMIAS. An inherited form of hemolytic anemia, thalassemia stems from the body's inability to manufacture as much normal hemoglobin as it needs. There are two categories of thalassemia, depending on which of the amino acid chains is affected. (Hemoglobin is composed of four chains of amino acids.) In alpha-thalassemia, there is an imbalance in the production of the alpha chain of amino acids; in beta-thalassemia, there is an imbalance in the beta chain. Alpha-thalassemias most commonly affect blacks (25% have at least one gene); beta-thalassemias most commonly affect people of Mediterranean ancestry and Southeast Asians. Characterized by production of red blood cells that are unusually small and fragile, thalassemia only affects people who inherit the gene for it from each parent (autosomal recessive inheritance). AUTOIMMUNE HEMOLYTIC ANEMIAS. Warm antibody hemolytic anemia is the most common type of this disorder. This condition occurs when the body produces autoantibodies that coat red blood cells. The coated cells are destroyed by the spleen, liver, or bone marrow. Warm antibody hemolytic anemia is more common in women than in men. About one-third of patients who have warm antibody hemolytic anemia also have lymphoma, leukemia, lupus, or connective tissue disease. In cold antibody hemolytic anemia, the body attacks red blood cells at or below normal body temperature. The acute form of this condition frequently develops in people who have had pneumonia, mononeucleosis, or other acute infections. It tends to be mild and short-lived, and disappears without treatment. Chronic cold antibody hemolytic anemia is most common in women and most often affects those who are over 40 and who have arthritis. This condition usually lasts for a lifetime, generally causing few symptoms. However, exposure to cold temperatures can accelerate red blood cell destruction, causing fatigue, joint aches, and discoloration of the arms and hands. SICKLE CELL ANEMIA. Sickle cell anemia is a chronic, incurable condition that causes the body to produce defective hemoglobin, which forces red blood cells to assume an abnormal crescent shape. Unlike normal oval cells, fragile sickle cells can't hold enough hemoglobin to nourish body tissues. The deformed shape makes it hard for sickle cells to pass through narrow blood vessels. When capillaries become obstructed, a life-threatening condition called sickle cell crisis is likely to occur. Sickle cell anemia is hereditary. It almost always affects blacks and people of Mediterranean descent. A child who inherits the sickle cell gene from each parent will have the disease. A child who inherits the sickle cell gene from only one parent carries the sickle cell trait, but does not have the disease. APLASTIC ANEMIA. Sometimes curable by bone marrow transplant, but potentially fatal, aplastic anemia is characterized by decreased production of red and white blood cells and platelets (disc-shaped cells that allow the blood to clot). This disorder may be inherited or acquired as a result of:
ANEMIA OF CHRONIC DISEASE. Cancer, chronic infection or inflammation, and kidney and liver disease often cause mild or moderate anemia. Chronic liver failure generally produces the most severe symptoms. People infected with the Human immunodeficiency virus (HIV) that causes AIDS often face severe fatigue. Causes and symptomsAnemia is caused by bleeding, decreased red blood cell production, or increased red blood cell destruction. Poor diet can contribute to vitamin deficiency and iron deficiency anemias in which fewer red blood cells are produced. Hereditary disorders and certain diseases can cause increased blood cell destruction. However, excessive bleeding is the most common cause of anemia, and the speed with which blood loss occurs has a significant effect on the severity of symptoms. Chronic blood loss is usually a consequence of:
Acute blood loss is usually the result of:
When a lot of blood is lost within a short time, blood pressure and the amount of oxygen in the body drop suddenly. Heart failure and death can follow. Loss of even one-third of the body's blood volume in the space of several hours can be fatal. More gradual blood loss is less serious, because the body has time to create new red blood cells to replace those that have been lost. SymptomsWeakness, fatigue, and a run-down feeling may be signs of mild anemia. Skin that is pasty or sallow, or lack of color in the creases of the palm, gums, nail beds, or lining of the eyelids are other signs of anemia. Someone who is weak, tires easily, is often out of breath, and feels faint or dizzy may be severely anemic. Other symptoms of anemia are:
In pernicious anemia, the tongue feels unusually slick. A patient with pernicious anemia may have:
Pernicious anemia can damage the spinal cord. A doctor should be notified whenever symptoms of this condition occur. A doctor should also be notified if a patient who has been taking iron supplements develops:
DiagnosisPersonal and family health history may suggest the presence of certain types of anemia. Laboratory tests that measure the percentage of red blood cells or the amount of hemoglobin in the blood are used to confirm diagnosis and determine which type of anemia is responsible for a patient's symptoms. X rays and examinations of bone marrow may be used to identify the source of bleeding. TreatmentAnemia due to nutritional deficiencies can usually be treated at home with iron supplements or self administered injections of vitamin B12. People with folic acid anemia should take oral folic acid replacements. Vitamin C deficiency anemia can be cured by taking one vitamin C tablet a day. Surgery may be necessary to treat anemia caused by excessive loss of blood. Transfusions of red blood cells may be used to accelerate production of red blood cells. Medication or surgery may also be necessary to control heavy menstrual flow, repair a bleeding ulcer, or remove polyps (growths or nodules) from the bowels. Patients with thalassemia usually do not require treatment. However people with a severe form may require periodic hospitalization for blood transfusions and/or bone marrow transplantation. SICKLE CELL ANEMIA. Treatment for sickle cell anemia involves regular eye examinations, immunizations for pneumonia and infectious diseases, and prompt treatment for sickle cell crises and infections of any kind. Psychotherapy or counseling may help patients deal with the emotional impact of this condition. VITAMIN B12 DEFICIENCY ANEMIA. A life-long regimen of B12 shots is necessary to control symptoms of pernicious anemia. The patient may be advised to limit physical activity until treatment restores strength and balance. APLASTIC ANEMIA. People who have aplastic anemia are especially susceptible to infection. Treatment for aplastic anemia may involve blood transfusions and bone marrow transplant to replace malfunctioning cells with healthy ones. ANEMIA OF CHRONIC DISEASE. There is no specific treatment for anemia associated with chronic disease, but treating the underlying illness may alleviate this condition. Erythropoietin is a hormone that stimulates production of red blood cells. It is sometimes used to treat anemia from kidney disease or cancer chemotherapy. This type of anemia rarely becomes severe. If it does, transfusions or hormone treatments to stimulate red blood cell production may be prescribed. A working group met in 2004 to address the specific management of anemia in patients infected with HIV. HEMOLYTIC ANEMIA. There is no specific treatment for cold-antibody hemolytic anemia. About one-third of patients with warm-antibody hemolytic anemia respond well to large doses of intravenous and oral corticosteroids, which are gradually discontinued as the patient's condition improves. Patients with this condition who don't respond to medical therapy must have the spleen surgically removed. This operation controls anemia in about one-half of the patients on whom it's performed. Immune-system suppressants are prescribed for patients whose surgery is not successful. Self-careAnyone who has anemia caused by poor nutrition should modify his or her diet to include more vitamins, minerals, and iron. Vitamin C can stimulate iron absorption. The following foods are also good sources of iron:
Because light and heat destroy folic acid, fruits and vegetables should be eaten raw or cooked as little as possible. Alternative treatmentAs is the case in standard medical treatment, the cause of the specific anemia will determine the alternative treatment recommended. If the cause is a deficiency, for example iron deficiency, folic acid deficiency, B12 deficiency, or vitamin C deficiency, supplementation is the treatment. For extensive blood loss, the cause should be identified and corrected. Other types of anemias should be addressed on a deep healing level with crisis intervention when necessary. Many alternative therapies for iron-deficiency anemia focus on adding iron-rich foods to the diet or on techniques to improve circulation and digestion. Iron supplementation, especially with iron citrate (less likely to cause constipation), is used by alternative practitioners. This can be given in combination with herbs that are rich in iron. Some examples of iron-rich herbs are dandelion (Taraxacum officinale), parsley (Petroselinum crispum), and nettle (Urtica dioica). The homeopathic remedy ferrum phosphoricum can also be helpful. An iron-rich herbal tonic can also me made using the following recipe:
Other herbal remedies used to treat iron-deficiency anemia aim to improve the digestion. Gentian (Gentiana lutea) is widely used in Europe to treat anemia and other nutritionally based disorders. The bitter qualities of gentian help stimulate the digestive system, making iron and other nutrients more available for absorption. This bitter herb can be brewed into tea or purchased as an alcoholic extract (tincture). Other herbs recommended to promote digestion include:
Traditional Chinese treatments for anemia include:
PrognosisFolic-acid and iron-deficiency anemiasIt usually takes three to six weeks to correct folic acid or iron deficiency anemia. Patients should continue taking supplements for another six months to replenish iron reserves. They should have periodic blood tests to make sure the bleeding has stopped and the anemia has not recurred. Pernicious anemiaAlthough pernicious anemia is considered incurable, regular B12 shots will alleviate symptoms and reverse complications. Some symptoms will disappear almost as soon as treatment begins. Aplastic anemiaAplastic anemia can sometimes be cured by bone marrow transplantation. If the condition is due to immunosuppressive drugs, symptoms may disappear after the drugs are discontinued. Sickle cell anemiaAlthough sickle cell anemia cannot be cured, effective treatments enable patients with this disease to enjoy longer, more productive lives. ThalassemiaPeople with mild thalassemia (alpha thalassemia trait or beta thalassemia minor) lead normal lives and do not require treatment. Those with severe thalassemia may require bone marrow transplantation. Genetic therapy is is being investigated and may soon be available. Hemolytic anemiaAcquired hemolytic anemia can generally be cured when the cause is removed. PreventionInherited anemias cannot be prevented. Genetic counseling can help parents cope with questions and concerns about transmitting disease-causing genes to their children. Avoiding excessive use of alcohol, eating a balanced diet that contains plenty of iron-rich foods, and taking a daily multivitamin can help prevent anemia. Methods of preventing specific types of anemia include:
ResourcesPeriodicals"Biopharmaceuitcal Company Announces Manufacturing Agreement for Anemia Drug." Obesity, Wellness, & Fitness Week (September 4, 2004): 406. "Management Strategy for Anemia in HIV Infection Elucidated." Immunotherapy Weekly (July 7, 2004): 75. Patient discussion about Anemias. Q. Well I’m a vegetarian and I might get anemia. How do I get Iron and protein without meat? My mom my take giant vitamin pills and eat nasty protein bars. It's not as bad killing animals though... Is their any way I can stay healthy? Also being a vegetarian has made me extremely under weight and I am probably going to get anemia if i don't get all my vitamins. HELP! A. You are, at least partially, what you eat, so it's important to take care of your diet. Being underweight, especially during adolescence, may pose substantial risk to the health. If your diet caused you to be underweight I would consider consulting a professional (e.g doctor, dietitian). Iron from vegetables is not as good as iron from meat. Foods rich in iron include whole or enriched breads or grains, iron-fortified cereals, legumes, green leafy vegetables, dried fruits, soy products, blackstrap molasses, bulgur, and wheat germ. Vitamin C helps the body to absorb the iron from the food better. You may read more here: http://www.nlm.nih.gov/medlineplus/vegetariandiet.html Q. What are the Symptoms of Anemia? Lately I've been feeling very tired. My friend suggested I might be anemic. What are the major symptoms of anemia? A. The symptoms of anemia vary according to the type of anemia, the underlying cause, and any underlying health problems. Anemia may be associated with other medical conditions such as hemorrhage, ulcers, menstrual problems or cancer -- and specific symptoms of those conditions may be noticed first. The body also has a remarkable ability to compensate for early anemia. If your anemia is mild or developed over a long period of time, you may not notice any symptoms. Symptoms common to many types of anemia include the following: Easy fatigue and loss of energy Unusually rapid heart beat, particularly with exercise Shortness of breath and headache, particularly with exercise Difficulty concentrating Dizziness Pale skin Leg cramps Insomnia Hope this helps. http://www.webmd.com/a-to-z-guides/understanding-anemia-symptoms Q. What is the Definition of Anemia? My doctor told me I have anemia, based on my latest blood tests. What is anemia? A. Anemia is defined as a deficiency of hemoglobin, a molecule inside the red blood cells (RBC's). The hemoglobin is responsible for carrying the oxygen that we breath from the lungs to the body tissues. Anemia causes lack of oxygen in the organs, in different degrees. A regular blood test can discover anemia, simply if the hemoglobin (Hb) level is lower than 13.0 g/dL in adult men and lower than 12.0 g/dL in adult women. The blood test can also suggest on the cause of the anemia, depending on other values that can be measured. Read more or ask a question about AnemiasHow to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
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| ? Mentioned in | ? References in periodicals archive | |
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" As for sports medicine, he explains, "I
started out researching anemias and bleeding in runners and swimmers;
when I began presenting it at sports medicine meetings, I found I liked
that crowd. The treated diseases have included thalassemia, Fanconi
anemia, Diamond-Blackfan anemia, Wiscott-Aldrich syndrome, and several
other anemias and leukemias. [10,11] In the adult population, steroids are used
successfully to treat certain types of anemias, hereditary angioedema,
some gynecologic conditions, protein anabolism, and male hypogonadism. |
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