What are the other Names for this Condition? (Also known as/Synonyms)

• AAT (Acquired Amegakaryocytic Thrombocytopenia)
• Acquired Pure Megakaryocytic Aplasia
• Severe Thrombocytopenia and Selective, Marked Decrease or Absence of Megakaryocytes

What is Acquired Amegakaryocytic Thrombocytopenia? (Definition/Background Information)

• Acquired Amegakaryocytic Thrombocytopenia (AAT) is a rare blood disorder that causes severe thrombocytopenia with no other blood abnormalities
• It is so named because the level of large bone marrow cells that produce platelets, called megakaryocytes, are significantly lower or absent
• Signs and symptoms of the condition include prolonged bleeding; easy bruising; rash (pinpoint red spots called petechia); bleeding in the mouth and gums; and/or frequent nosebleeds
• There are many potential causes of Acquired Amegakaryocytic Thrombocytopenia
• Although standard treatment guidelines have not been established, various immunosuppressive treatment approaches have been utilized with success in affected people

(Source: Acquired Amegakaryocytic Thrombocytopenia; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

• Acquired Amegakaryocytic Thrombocytopenia can arise from a variety of causes including any disease/condition that affects the bone marrow, medications that can generate an immune response in the body to destroy platelets, and certain nutritional deficiencies

Who gets Acquired Amegakaryocytic Thrombocytopenia? (Age and Sex Distribution)

• Acquired Amegakaryocytic Thrombocytopenia is a rare blood disorder
• Both males and females may be affected
• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for Acquired Amegakaryocytic Thrombocytopenia? (Predisposing Factors)

The risk factors for Acquired Amegakaryocytic Thrombocytopenia may include:

• A viral or bacterial infection
• Pregnancy
• Autoimmune disorders
• Use of certain medications/drugs
• Cancer and cancer treatment

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Acquired Amegakaryocytic Thrombocytopenia? (Etiology)

There are many potential causes of Acquired Amegakaryocytic Thrombocytopenia. The condition may be associated with the following factors:

• Viral and bacterial infections
• Chemotherapy
• Exposure to environmental toxins
• Autoimmune diseases (such as systemic lupus erythematosus)
• Drug sensitivities
• Pregnancy

In some people, the condition is an early sign of a more severe progressive disease, such as aplastic anemia, myelodysplasia, or leukemia.

(Source:Acquired Amegakaryocytic Thrombocytopenia; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

What are the Signs and Symptoms of Acquired Amegakaryocytic Thrombocytopenia?

The signs and symptoms of Acquired Amegakaryocytic Thrombocytopenia vary, but may include:

• Prolonged bleeding, even from minor cuts
• Easy bruising
• Rash (pinpoint red spots called petechia)
• Bleeding in the mouth and gums
• Frequent nosebleeds

(Source: Acquired Amegakaryocytic Thrombocytopenia; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

How is Acquired Amegakaryocytic Thrombocytopenia Diagnosed?

A diagnosis of Acquired Amegakaryocytic Thrombocytopenia is often suspected based on the presence of characteristic signs and symptoms. Additional testing can then be ordered to confirm the diagnosis. This may include:

• Complete blood count (CBC)
• Blood smear
• Blood clotting studies (PTT and PT)
• Bone marrow tests (i.e. a bone marrow aspiration and/or biopsy)

Once the diagnosis is confirmed, a healthcare provider will likely recommend other tests in an attempt to determine the underlying cause of the condition.

(Source: Acquired Amegakaryocytic Thrombocytopenia; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Acquired Amegakaryocytic Thrombocytopenia?

The complications of Acquired Amegakaryocytic Thrombocytopenia may include:

• Severe blood loss leading to anemia
• Bone marrow failure
• Heart abnormalities
• Bleeding within the gastrointestinal tract and other organs
• Hemorrhage in the brain
• In pregnant women, the condition can result in excessive bleeding in a newborn

Complications may occur with or without treatment, and in some cases, due to treatment also.

How is Acquired Amegakaryocytic Thrombocytopenia Treated?

• Standard treatment guidelines have not been established for Acquired Amegakaryocytic Thrombocytopenia. However, various immunosuppressive treatment approaches have been utilized in affected people
• In several case reports, affected people were successfully treated with cyclosporine either alone or in combination with other immunosuppressive medications (i.e. antithymocyte globulin)
• Other therapies for Acquired Amegakaryocytic Thrombocytopenia have included rituximab, danazol, azathioprine, and bone marrow transplant with variable success

(Source: Acquired Amegakaryocytic Thrombocytopenia; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

How can Acquired Amegakaryocytic Thrombocytopenia be Prevented?

The following are some methods for prevention of Acquired Amegakaryocytic Thrombocytopenia:

• Discontinuing use of medication/drug that is identified as the causative agent of AAP
• Avoid physical injuries or trauma that could result a bleeding episode
• Seek medical attention immediately following incidences of spontaneous bleeding or bruising
• Seek medical attention for any underlying condition that can cause AAP
• Avoiding indiscriminate use of certain drugs such as painkillers

Regular medical screening at periodic intervals with tests and physical examinations are recommended.

What is the Prognosis of Acquired Amegakaryocytic Thrombocytopenia? (Outcomes/Resolutions)

• The long-term outlook (prognosis) for people with Acquired Amegakaryocytic Thrombocytopenia varies based on the underlying cause
• Some people respond well to treatment and long-term remissions have been documented in several case reports
• In others, the condition progresses rapidly to aplastic anemia or myelodysplasia. There are currently no good predictors to aid in assessing the likelihood of response to therapy or overall prognosis

(Source: Acquired Amegakaryocytic Thrombocytopenia; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

Additional and Relevant Useful Information for Acquired Amegakaryocytic Thrombocytopenia:

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/diseases-conditions/rare-disorders/