Transient myeloproliferative disorder in a Down's neonate with rearranged T-cell receptor beta gene and evidence of in vivo maturation demonstrated by dual-colour flow cytometric DNA ploidy analysis

Leukemia. 1993 Oct;7(10):1667-71.


Neonates with Down's syndrome may develop a transient myeloproliferative disorder (TMPD) which on presentation is indistinguishable from acute leukemia, with the difference manifest only on follow-up. The clinical course is one of spontaneous remission in TMPD and relentless progression in leukemia. We describe a Down's neonate presenting with hyperleucocytosis and circulating blasts which were positive for CD34, myeloid (CD33), megakaryocytic (CD41, CD42b, CD61), and T-lineage (CD3, CD7), but not B-lineage, associated antigens. Clonal rearrangement of the T-cell receptor beta (TCR beta) gene was found, with the immunoglobulin heavy chain gene in germline configuration, showing the disease to be a clonal proliferation of a multipotential stem cell involving the myeloid and T lineages. Dual-colour flow cytometric DNA ploidy analysis of CD41 positive blasts showed initially a predominant 2N population, but polyploidization to 6N and 8N cells was found on follow-up, concomitant with a progressive decrease in circulating blasts, suggesting maturation of the abnormal clone and a provisional diagnosis of TMPD. This was shown by the eventual resumption of normal haemopoiesis with the disappearance of blasts and the clonally rearranged TCR beta gene.

Publication types

  • Case Reports

MeSH terms

  • Bone Marrow / chemistry
  • Bone Marrow / physiology
  • DNA / genetics*
  • Down Syndrome / blood
  • Down Syndrome / complications*
  • Down Syndrome / genetics*
  • Flow Cytometry / methods
  • Gene Rearrangement / genetics
  • Gene Rearrangement, beta-Chain T-Cell Antigen Receptor / genetics*
  • Genes, Immunoglobulin / genetics
  • Humans
  • Immunophenotyping
  • Infant, Newborn
  • Karyotyping
  • Leukocytosis / blood
  • Male
  • Myeloproliferative Disorders / complications*
  • Myeloproliferative Disorders / diagnosis
  • Myeloproliferative Disorders / genetics*
  • Ploidies*


  • DNA