What is aplastic anemia?

What is aplastic anemia?

• A. A condition where T-cells attack bone marrow stem cells, leading to pancytopenia
• B. A deficiency of iron causing microcytic anemia
• C. A genetic disorder causing increased red blood cell destruction
• D. Overproduction of white blood cells

Answer: (A)

Aplastic anemia is bone marrow failure caused by an autoimmune attack on hematopoietic stem cells, which leads to pancytopenia—low red cells, white cells, and platelets. In this condition the marrow becomes hypocellular and is often fatty, so its ability to produce all blood cell lines drops, resulting in a low reticulocyte count and symptoms like fatigue, infections, and easy bruising or bleeding. The immune mechanism is commonly T-cell–mediated suppression of the stem cells, and various triggers (drugs, chemicals, radiation, infections) can precipitate it. The other descriptions fit different problems: iron deficiency causes a microcytic anemia from impaired hemoglobin synthesis; a genetic disorder causing increased red cell destruction points to hemolytic anemias; and overproduction of white blood cells suggests a leukemia or other myeloproliferative process.

Aplastic anemia is bone marrow failure caused by an autoimmune attack on hematopoietic stem cells, which leads to pancytopenia—low red cells, white cells, and platelets. In this condition the marrow becomes hypocellular and is often fatty, so its ability to produce all blood cell lines drops, resulting in a low reticulocyte count and symptoms like fatigue, infections, and easy bruising or bleeding. The immune mechanism is commonly T-cell–mediated suppression of the stem cells, and various triggers (drugs, chemicals, radiation, infections) can precipitate it. The other descriptions fit different problems: iron deficiency causes a microcytic anemia from impaired hemoglobin synthesis; a genetic disorder causing increased red cell destruction points to hemolytic anemias; and overproduction of white blood cells suggests a leukemia or other myeloproliferative process.