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Aplastic Anemia - The DiseaseAplastic anemia is a rare but extremely serious disorder that results from the unexplained failure of the bone marrow to produce blood cells. In all probability you had never heard of this disease until the time of diagnosis. We hope that this pamphlet helps you deal with your situation by providing basic information about aplastic anemia and the various treatment options. This pamphlet is not intended as a substitute for the advice of a physician. It is important that you ask questions and learn as much as you can about this disease. By contacting the Aplastic Anemia Foundation of America, you can be connected with others in your same situation and receive information free of charge. There are AAFA chapters around the country. You do not need to be alone in dealing with aplastic anemia. Normal Bone Marrow FunctionThe central portion of bones is filled with a spongy red tissue called bone marrow. The bone marrow is essentially a factory producing the cells of the blood: red cells that carry oxygen from the lungs to all areas of the body, white cells that fight infection by attacking and destroying germs, and platelets that control bleeding by forming blood clots in areas of injury. Continuous production of blood cells is necessary all through life because each cell has a finite life span once it leaves the bone marrow and enters the blood: red cells--120 days, platelets--6 days, and white cells--one day or less! Fortunately, the bone marrow is a superb blood cell factory and ordinarily supplies as many cells as needed, increasing production of red cells and platelets when bleeding occurs and of white cells when infection threatens. Bone Marrow Stem Cells and EnvironmentThe bone marrow contains a small number of precious stem cells. Just as plant seeds give rise to both mature plants and new seeds for the next generation of plants, so do the bone marrow stem cells produce blood cells and new stem cells in a lifelong cycle of production and self-renewal. Bone marrow stem cells require a proper environment for normal function. Just as a seed cannot grow in poor soil, bone marrow stem cells cannot survive and multiply in a poor environment. Failure of the bone marrow cell production can result from damage to the stem cells or to the environment. The result is aplastic anemia. Bone Marrow FailureWhen the bone marrow cell production fails, normal blood levels of red cells, white cells and platelets begin to fall. Symptoms of anemia, bleeding and infection develop when blood cell levels fall to dangerously low levels. The DiagnosisThe diagnosis of aplastic anemia begins with a blood test. Blood cell levels are normally maintained within certain ranges. The diagnosis of aplastic anemia is suspected when all three blood cell levels are very low. In aplastic anemia, the bone marrow biopsy shows a great reduction in the number of cells in the bone marrow, with a normal appearance of the few remaining cells. The diagnosis of aplastic anemia is usually made or confirmed by a hematologist- a specialist in blood disorders. Initial TreatmentAplastic anemia is a medical emergency. Patients with severe aplastic anemia require immediate hospital treatment. Platelets are collected from donors through a process called hemapheresis. Donating usually takes three hours. Platelets are collected from a vein in the donor's arm, passed through a blood-separating machine and returned to the donor. The platelets that are removed are then given to the aplastic anemia patient. The donor's body replaces the platelets within a day or two. Antibiotics: Because of their extremely short life span, white cells cannot be effectively replaced by a transfusion. Therefore, control of infection depends on prompt, appropriate intravenous antibiotic therapy as soon as fever or other signs of infection appear. Isolation: To prevent transfer of infection to aplastic anemia patients, they must often be isolated from even healthy people ("reverse quarantine"). Necessary visitors may have to wear masks and gown and must always thoroughly wash hands before touching the patient. Activity: Activity must be restricted to reduce symptoms of anemia, avoid falls or accidents that could provoke bleeding,and reduce contact with other people. What You Can Do:Take charge of your illness! Bone Marrow TransplantationBone marrow transplantation is now being used more and more frequently for aplastic anemia patients who are good candidates and who have a matched donor. Identical twins or perfectly matched siblings are the best choices for bone marrow donors for patients. If a patient does not have a perfect match within the family, a search of existing bone marrow registries may be undertaken to find a matched, unrelated donor. Drug TherapiesDoctors may recommend that the patient start on drug therapy while searching for a donor, or drug therapy may be the best choice for treatment for that patient. New therapies are being developed all the time. Be sure to talk with the doctor about what is available. Another immunosuppressive drug is cyclosporin, which may be given alone or in combination with androgens, antilymphocyte globulin or serum. It is thought that cyclosporin plus androgens may stimulate blood cell production. Hematopoietic growth factors are products of the new genetic engineering. These are copies of substances which occur naturally in the human body, but produced in larger quantities in the laboratory Colony stimulating factors (CSFs) act to stimulate colonies of cells, such as red cells. Interleukin-3 (IL-3) stimulates production of other cells. It is thought that a combination of the growth factors might work in treating aplastic anemia. Other drug therapies are being developed all the time. Your doctor will be able to help you explore these options. Frequently Asked Questions:Who gets aplastic anemia?
What are the causes of aplastic anemia?Aplastic anemia has been clearly linked to radiation, environmental toxins, insecticides, and drugs in much the same fashion that cancer has been linked to these agents. Benzene-based compounds, airplane glue, and drugs such as chloramphenicol have been linked to aplastic anemia. In some individuals, aplastic anemia is believed to be caused by a virus. To date the exact cause of the disease in over half the cases is unknown, or idiopathic. Are there any experimental treatments available for those who do not respond to ATG and do not have a bone marrow transplant match? How do I find out where in my area there is experimental research going on? What activities should I avoid? Glossaryaplastic anemia: bone marrow failure; for unknown reasons, production of blood cells slows or stops. antibody: a complex molecule produced by lymph tissue in response to the presence of an antigen; antibodies neutralize the effect of the antigen. antigen: foreign substance which is not usually part of the body's makeup, and that stimulates antibody production; this antibody reacts specifically with a particular antigen to destroy or weaken it. bacteria: organism that can cause infection. bone marrow: soft tissue within the bones where blood cells are manufactured. bone marrow aspiration: test in which a sample of bone marrow cells is removed with a needle and examined under a microscope. bone marrow biopsy: procedure in which a small piece of bone marrow tissue is removed with a needle; sample is processed by softening the bone and examining thin slices of the softened bone under a microscope. bone marrow transplant: procedure in which bone marrow filled with disease is destroyed by radiation or chemotherapy and then replaced with healthy cells from a donor. chromosome: a rodlike structure that appears in the nucleus of a cell during division; contains the genes responsible for heredity. complete blood count: CBC; amount or level of blood cells: white cells, red cells and platelets. cross match: type and cross; test in which the blood cells of a donor and a recipient are mixed together to determine if they are compatible. culture: procedure used to identify the source of infection; specimen of blood, urine, sputum or stool is taken and tested to determine the type of infection and the appropriate antibiotic. differential: percent of different types of blood cells in the blood. hemoglobin: Hg; iron-containing coloring in the red cells that combine with oxygen from the lungs and carries it to the body's cells. histocompatibility antigens: HLA; a group of DNA substances in chromosomes that determine whether certain tissues can be transplanted; also can be used to determine the most compatible platelet donors. Histocompatibility: the tissue typing test done on white cells to determine if a donor and recipient are compatible. immunosuppression: decrease in the ability of the body's normal immune response to the invasion of foreign material. lymphocyte: a type of white cell that fights infection by producing antibodies and other defense substances; occurs in 2 forms: B cells that recognize specific antigens and produce antibodies against them, and T cells that are agents of the immune system. neutropenia: low neutrophil (poly) count. pancytopenia: low number of blood cells. petechiae: tiny red dots on the skin due to bleeding under the skin caused by low platelet counts. peripheral blood: blood in the bloodstream. platelet: blood cell that prevents bleeding and bruising. red blood cell: oxygen carrying cell in the blood which contains the pigment hemoglobin, produced in the bone marrow; erythrocyte. stem cell: cell from which platelets, red blood cells and white blood cells grow in the one marrow. white blood cells: blood cells which fight infection. |
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| Last Modified July 23, 2008 | ||||