Transient abnormal myelopoeisis in newborns with Down syndrome.

Transient abnormal myelopoeisis (TAM) is a haematological phenomenon commonly seen in newborns with Down syndrome. Although the majority show spontaneous resolution, this condition should not be dismissed too readily as there have been associated fatalities. Furthermore, even for those who do show spontaneous resolution, a significant percentage will develop acute megakaryoblastic leukaemia within the next few years of life. We report a series of four patients with TAM who presented with hepatosplenomegaly and leucocytosis detected on preliminary investigations.