Vesiculopustular eruptions in Down syndrome neonates with myeloproliferative disorders

Background: Infants with Down syndrome are at increased risk for hematologi c abnormalities, including leukemoid reaction, transient myeloproliferative disorder, and congenital leukemia. The differential diagnosis of a vesicul opustular eruption in an infant with Down syndrome and these hematologic ab normalities is broad and includes benign, self-limited disorders as well as life-threatening infections. Observation: We describe 3 newborns with Down syndrome and vesiculopustular eruptions associated with myeloproliferative disorders during the neonatal period. These lesions differ from other neonatal vesicular eruptions in th at they have a unique distribution, display pathergy, and contain immature hematopoietic cells similar to circulating blast cells. Resolution occurs w ithout treatment as the hematologic disorder subsides. Conclusions: Infants with Down syndrome and hematologic abnormalities may h ave a cutaneous eruption that has characteristic clinical and histopatholog ic findings. It is possible that this eruption has been unrecognized in the past because of its self-limited course. Whether this eruption is a progno stic factor for the subsequent development of leukemia is uncertain.