Web Watch - - Aplastic Anemia

By Shirley Butler

 

Aplastic anemia is a rare but extremely serious disorder resulting from the unexplained failure of the bone marrow to produce blood cells. It has been linked to radiation, environmental toxins, insecticides, and drugs in much the same fashion as cancer. Benzene-based compounds, airplane glue, and drugs such as chloramphenicol have been named as links. 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. The disease can strike down literally anyone: men and women, children as well as adults, any race or socioeconomic status.

 

The 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-- 1 20 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.

 

The 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 envirorunent 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.

 

When 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. Confirmation of the diagnosis requires examination of a small sample of bone marrow under the microscope.

 

Aspiration and biopsy of the bone marrow is easily carried out in the examining room or hospital bed by inserting a sturdy needle into the large pelvic bone just beneath the belt line on either side of the spine. This procedure is made more tolerable by the use of Novocain-like drugs to "numb up" the skin and bone.

 

Aplastic anemia is a medical emergency. Patients with severe aplastic anemia require immediate hospital treatment and all, or a combination of the following therapies: 1) Blood, 2) Transfusion, 3) Antibiotics, 4) Isolation (to prevent transfer of infection to aplastic anemia patients from healthy people) and 5) Reduction of Activity. Activity must be restricted to reduce symptoms of anemia, avoid falls or accidents that could provoke bleeding, and to reduce contact with other people-. Drug Therapy with one of several immunosuppressive drugs, i.e. antithymocyte globulin, antilymphocyte globulin, and cyclosporin is important. And finally, it is worthwhile remembering that new therapies are being developed.