ALTERNATE NAMES

AAT; Acquired Pure Megakaryotic Aplasia; CAMT; Congenital Amegakaryocytic Thrombocytopenia; IBMFS; Inherited Bone Marrow Failure Syndrome; Thrombocytopenia Congenital Amegakaryotic

DESCRIPTION

Amegakaryocytic Thrombocytopenia is a rare, inherited bone marrow failure syndrome (IBMFS) in young children where the bone marrow fails to produce platelets or megakaryocytes. This prohibits the blood from clotting clot if they start to bleed. Over time, the bone marrow may also cease making red blood cells and neutrophils. Mutation of the gene Amega (MPL) is the cause of the disease. Clinical manifestations including petechiae (tiny purplish, red spots of bleeding into the skin), bruising, and bleeding, usually beginning at birth or within the first year of life.

About half of the people with IBMFS have characteristic physical findings including neurologic and cardiac anomalies. Over time, complete failure of the bone marrow to produce other blood products (aplastic anemia) also occurs in nearly half of the children. The diagnosis of this syndrome is usually made by 1 month of age. Some people are at risk for developing leukemia (cancer in the blood forming tissue of bone marrow).

DIAGNOSTIC TESTING, PHYSICAL FINDINGS, AND ICD-9-CM/ICD-10-CM CODING

Diagnostic testing: Definitive diagnostic lab testing includes MPL analysis (genetic testing); bone marrow aspirate, and biopsy specimens showing normal cellularity, with markedly reduced or absent megakaryocytes. Laboratory studies are needed to confirm the diagnosis.

Physical findings: Individuals with this condition may have:

• •

  Bruising;

• •

  Bleeding, which can be life threatening; and

• •

  Petechiae.

Children with IBMFS can also have:

• •

  Central nervous system abnormalities;

• •

  Delays of psychomotor development;

• •

  Cardiac defects; and

• •

  Other rare malformations.

ICD-9: 287.33

ICD-10: D69.6

PROGRESSION

Onset begins within the first month of life. Life-threatening complications include:

• •

  Thrombocytopenic bleeding;

• •

  Aplastic anemia; and

• •

  Malignant myeloid leukemia.

TREATMENT

Stem cell transplant remains the only curative treatment for this disorder. Only small fractions of people have a suitable sibling transplant donor. Children with this disorder are treated with platelet transfusions.

Suggested MER for Evaluation:

• •

  Clinical examination that describes diagnostic features of the impairment; and

• •

  Laboratory tests showing results of chromosomal and gene analysis.

Suggested Listings for Evaluation:

DETERMINATION

LISTING

REMARKS

Meets

107.10

Disorders of bone marrow failure

Equals