Acquired amegakaryocytic thrombocytopenia 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 the condition. Although standard treatment guidelines have not been established, various immunosuppressive treatment approaches have been utilized with success in affected people. 

There are many potential causes of acquired amegakaryocytic thrombocytopenia. For example, the condition can be associated with:

• Viral infections
• Bacterial infections
• Chemotherapy
• Exposure to environmental toxins
• Autoimmune diseases (i.e. 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.

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

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.

To determine the best treatment for you or a family member, please speak with a healthcare provider.

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.

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.