TY - JOUR T1 - Trisomy 21 associated transient neonatal myeloproliferation in the absence of Down’s syndrome JF - Archives of Disease in Childhood - Fetal and Neonatal Edition JO - Arch Dis Child Fetal Neonatal Ed SP - F215 LP - F217 DO - 10.1136/fn.79.3.F215 VL - 79 IS - 3 AU - M Richards AU - J Welch AU - A Watmore AU - D Readett AU - A J Vora Y1 - 1998/11/01 UR - http://fn.bmj.com/content/79/3/F215.abstract N2 - Although usually associated with Down’s syndrome, transient neonatal myeloproliferation (TMD) can occur in the absence of a constitutional trisomy 21. This report describes two such cases, both of whom had a trisomy 21 restricted to clonal cells. Unlike in previous such reported cases, spontaneous morphological, cytogenetic, and molecular remission in both cases was followed by re-emergence, in one case, of an evolved clone with a more malignant phenotype which required pharmacological intervention. Awareness that trisomy 21 bearing leukaemia in the neonatal period can be transient even in the absence of Down’s syndrome is important to prevent unnecessary treatment. Equally, such cases require indefinite follow up as a proportion may have a recurrence which may require treatment. ER -