Declining total leucoyte count, an indication of transient abnormal myelopoisis

Neonates with Down syndrome have an increased predisposition to transient abnormal myelopoisis, a haematological abnormality which is characterized by uncontrolled proliferation of myeloblasts. The unique ability of this disorder to spontaneously enter in to a state of remission led to the creation of a new class in 2008 World Health Organization (W.H.O.) classification of haemopoitic and lymphoid tumours. It has now been classified as transient abnormal myelopoisis (TAM). The cause of remission is still not clear although it is possibly linked to the abnormal expression of GATA-1 transcription factor and to a switch from hepatic haematopoesis to medullary haematopoesis. Simple laboratory monitoring by serial complete blood count and peripheral smear can give indication of this rare disorder. As very few cases of this disorder exist we share our experience and report a case of transient myeloproliferative disorder in a male newborn having Down syndrome.