Aplastic anemia

Anemia due to failure of the bone marrow to produce blood cells, including red and white blood cells as well as platelets. Aplastic anemia frequently occurs without a known cause. Causes of aplastic include chemicals (benzene, toluene in glues, insecticides, solvents), drugs (chemotherapy, gold, seizure medications, antibiotics, and others), viruses (HIV, Epstein-Barr), radiation, immune conditions (systemic lupus erythematosus, rheumatoid arthritis), pregnancy, paroxysmal nocturnal hemoglobinuria, and inherited disorders (Fanconi's anemia). Symptoms of aplastic anemia depend upon the severity. Symptoms include fatigue, bruising, bleeding, shortness of breath, fever, chills, and less frequently, bone pain. The diagnosis of aplastic anemia is based on the presence of low red and white blood cell and platelet counts and a decrease in the normal cells of the bone marrow. Treatment of aplastic anemia is based on the severity of the condition and the age of the patient affected. All medications which could suppress the bone marrow are discontinued. Male hormone (androgens) are sometimes given to stimulate the suppressed bone marrow to become more active. Bone marrow stimulating factors are now manufactured in laboratories and are often given intravenously. Blood transfusions can be required. Precautions to avoid infections and even antibiotics are given when the white blood cell counts are severely lowered. Bone marrow transplantation is considered when genetically matched marrows are available. For older patients, suppression of the immune system may be necessary. This immunosuppression therapy can include antithymocyte globulin,

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aplastic anemia n anemia that is characterized by defective function of the blood-forming organs (as the bone marrow) and is caused by toxic agents (as chemicals or X-rays) or is idiopathic in origin called also hypoplastic anemia

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any of a diverse group of anemias characterized by bone marrow failure with reduction of hematopoietic cells and their replacement by fat, resulting in pancytopenia, often accompanied by granulocytopenia and thrombocytopenia. It may be hereditary; it may be secondary to causes such as toxic, radiant, or immunologic injury to bone marrow stem cells or their microenvironment; it may be associated with various diseases; or it may be idiopathic.