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Aplastic Anemia

(Hypoplastic Anemia)


Evan M. Braunstein

, MD, PhD, Johns Hopkins University School of Medicine

Last full review/revision Apr 2021| Content last modified Apr 2021
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Aplastic anemia is a disorder in which the cells of the bone marrow that develop into mature blood cells are damaged, leading to low numbers of red blood cells, white blood cells, and/or platelets.

The term aplastic anemia is used to refer to anemia that occurs when production of all types of blood cells is suppressed. If production of only red blood cells is suppressed, the disorder is called pure red blood cell aplasia.

When the cause of aplastic anemia cannot be diagnosed (called idiopathic aplastic anemia), the cause is likely an autoimmune disorder Autoimmune Disorders An autoimmune disorder is a malfunction of the body's immune system that causes the body to attack its own tissues. What triggers autoimmune disorders is not known. Symptoms vary depending on... read more , in which the immune system suppresses bone marrow stem cells.

Other causes include

Symptoms of Aplastic Anemia

Symptoms of aplastic anemia usually develop slowly over weeks to months.

The anemia causes fatigue, weakness, and paleness. The leukopenia causes increased susceptibility to infection. The thrombocytopenia causes easy bruising and bleeding.

Diagnosis of Aplastic Anemia

  • Blood tests

  • Bone marrow examination

Blood tests are done in people who have symptoms of anemia. When blood tests show that all blood cell numbers are reduced , a bone marrow examination is done.

Treatment of Aplastic Anemia

  • Stem cell transplantation

People with severe aplastic anemia may die unless immediately treated. Transfusions Overview of Blood Transfusion A blood transfusion is the transfer of blood or a blood component from one healthy person (a donor) to a sick person (a recipient). Transfusions are given to increase the blood's ability to... read more Overview of Blood Transfusion of red blood cells, platelets, and substances called growth factors may temporarily increase the numbers of red blood cells, white blood cells, and platelets.

Stem cell transplantation Stem Cell Transplantation Stem cell transplantation is the removal of stem cells (undifferentiated cells) from a healthy person and their injection into someone who has a serious blood disorder. (See also Overview of... read more is the usual treatment in aplastic anemia because it may cure the disease, especially in younger people who have a matched stem cell donor. If transplantation is not possible, people are given antithymocyte globulin and cyclosporine to suppress the immune system and allow the bone marrow stem cells to regenerate.

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