Amegakaryocytic Thrombocytopenia

Excerpt

Thrombocytopenia, a platelet count of less than 150,000 cells/μL for adults and children, is a common clinical finding with multiple potential etiologies. Amegakaryocytic thrombocytopenia is a severe form marked by reduced or absent megakaryocytes and no additional abnormalities on bone marrow evaluation. First described by Greenwald and Sherman in the pediatric literature in 1929, there are both congenital and acquired forms.

Congenital amegakaryocytic thrombocytopenia (CAMT) is an autosomal recessive disorder presenting with severe thrombocytopenia at birth. An almost universal progression to bone marrow failure with impaired production of all three hematopoietic cell lines occurs.

Acquired amegakaryocytic thrombocytopenia (AAMT) is likely immune-mediated and presents later in life. Generally, the other cell lines remain intact, but progression to bone marrow failure is possible.