Transient abnormal myelopoiesis (TAM) is a phenomenon that can happen in the fetuses or neonates with trisomy 21. The condition can mimic leukemia.
The estimated incidence is at ~10% of newborns with trisomy 21 3.
In the context of known trisomy 21, features that may suggest towards the diagnosis include:
- development of fetal hepatomegaly/fetal hepatosplenomagaly: tends to give hypoechoic hepatomegaly 4-5
Treatment anf prognosis
Although is can closely mimic leukemia most neonates who survive 4 to 8 weeks show complete remission. There is however a very high risk development of acute myeloid leukemia around 2-3 years of age.
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- 4. Kikuchi A, Tamura N, Ishii K et-al. Four cases of fetal hypoechoic hepatomegaly associated with Trisomy 21 and transient abnormal myelopoiesis. Prenat. Diagn. 2007;27 (7): 665-9. doi:10.1002/pd.1738 - Pubmed citation
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