• symptoms and signs

• laboratory findings

• about the disease

• prevention

• treatment

• prognosis

Symptoms and signs.  usually insidious in onset, occurring weeks or months after exposure to the toxin; weakness, fatigue, dyspnea, and waxy pallor of the skin and mucous membranes; hemorrhage into mucous membranes, skin, and optic fundi secondary to thrombocytopenia; frequent and severe infections secondary to agranulocytosis

Laboratory findings. decreased RBCs (normochromic, normocytic), WBCs, and hemoglobin (Hgb); decreased platelet count; increased serum iron; hypocellular/hypoplastic; fatty, fibrous tissue on bone marrow biopsy; markedly decreased reticulocyte count

About the disease. In aplastic anemia, there is a reduction in the number of circulating red blood cells resulting from bone marrow failure and generally accompanied by a decrease in the number of granulocytes (agranulocytosis) and/or decrease in the number of platelets (thrombocytopenia). Common causes implicated include chemicals, drugs, viruses, or radiation; the etiology is unknown in half of diagnosed cases. Exposure to a known or unknown toxin depresses production of erythrocytes, platelets, and granulocytes in the bone marrow. Common toxins include ionizing radiation, chemical agents (e.g., benzene, DDT, carbon tetrachloride), and drugs (e.g., antitumor or antimicrobial agents).

Prevention.  identification and avoidance of causative agent

Treatment.  removal of etiologic agent, e.g., toxin; bone marrow transplant from a human leukocyte antigen (HLA)-matched donor (sibling); prevention of hemorrhage; blood transfusion; antibiotics for infection; androgens to stimulate bone marrow growth; corticosteroids to stimulate granulocyte production

Prognosis. possible complications include hemorrhage and repeated infections, which result in death in about half of those diagnosed