Treatment For Aplastic Anemia
Patients with mild or moderate aplastic anemia generally do not require immediate treatment. Indeed, it is not known if they would benefit from early use of any of the therapies described below. They should be watched carefully for any decline in their blood counts. If such patients require transfusions, a decision should be made whether any of the below therapies should be employed even though they do not meet strict criteria for severe aplastic anemia. For the patient with severe aplastic anemia, treatment should begin within 4 weeks after presentation. Spontaneous increase in blood counts after 2-3 weeks is less likely and potential for mortality and morbidity increase rapidly. Three types of therapy are known to have benefit. These are bone marrow transplantation, immunosuppression with medicines such as antithymocyte globulin (ATG) and/or cyclosporine, and hematopoietic growth factors such as granulocyte colony stimulating factors (G-CSF), granulocyte monocyte colony stimulating factor (GM-CSF), or other cytokines.
A bone marrow transplant is the treatment of choice for patients with severe or very severe aplastic anemia less than 55-65 years of age in good medical condition who have an HLA identical family member. In this procedure the patient is given toxic doses of chemo- and/or radiotherapy and then infused with bone marrow from their HLA identical donor. If there is no family member, a search of the unrelated bone marrow transplant donor registries should be initiated even though the patient will initially be treated with another modality. A bone marrow transplant center should be contacted to provide further information and to discuss specific patient needs prior to referral.
The mainstay of initial therapy for the patient without HLA identical sibling donor is immunosuppression. ATG, and anti-T cell agent, is given intravenously over 4 to 10 days according to various inpatient protocols. This medicine frequently results in high fevers, moderate patient discomfort during its administration, and may transiently increase transfusion requirements. More recently, ATG is being given in combination with cyclosporine-A, an oral anti-T cell agent, and sometimes with prednisone as well. The combination of medicines seems to result in a higher frequently of clinical response than any of the medications given alone. However, even in patients who respond to these agents blood cell production, although usually adequate to maintain a reasonable quality of life, frequently is not normal even many years later.
More recently, therapy has been attempted with bioengineered molecules that increase the production of blood cell elements. All of these medications are administered either subcutaneously or intravenously and usually must be continued indefinitely once a response is obtained. G- and GM-CSF stimulate the white blood cells and in a few cases with prolonged use have resulted in small increments in platelets and red blood cells as well. Erythropoietin may increase red blood cell production, but most patients with aplastic anemia already have a very high erythropoietin level. Other cytokines such as interleukin-3 (IL-3), IL-6 and IL-11 may also have a role in raising platelet and white cell counts but these agents are currently available only as part of clinical research trials.
Treatment For Aplastic Anemia
