Abstract
Transient abnormal myelopoiesis（TAM）occurs in approximately 5-10％ of newborns with Down syndrome, and approximately 20％ of cases are severe. In recent years, it has been reported that early chemotherapy with low-dose cytarabine improves the prognosis of severe TAM. However, the use of cytarabine to treat newborns with severe TAM and persistent pulmonary hypertension of the newborn（PPHN）has not been reported previously. We report four cases in which infants with Down syndrome presented with TAM and persistent PPHN. Case 1: A female infant was delivered after 40 weeks and 0 days of gestation, with a birth weight of 2,635g. She was treated with a steroid for pericardial effusion. She was discharged from hospital on day 34. Case 2: A female infant was delivered after 32 weeks and 1 day of gestation, with a birth weight of 2,309g. She received chemotherapy from day 11, but died of hepatic failure on day 45. Case 3: A female infant was delivered after 36 weeks and 1 day of gestation, with a birth weight of 2,743g. She showed evidence of advanced hepatic fibrosis and died on day 34. Case 4: A male infant was delivered after 37 weeks and 0 days of gestation, with a birth weight of 3,122g. He received chemotherapy from day 16, but died of multiple organ dysfunction on day 28. At our hospital, only neonatologists treat severe TAM. Three of the 4 abovementioned patients could not be saved, and there is a possibility that low-dose cytarabine treatment was delayed too long. It is difficult for neonatologists to determine whether cytarabine chemotherapy should be administered in the early stages after birth. As it is difficult to treat newborns with severe TAM, it is necessary for neonatologists and pediatric hematologists to cooperate in such cases.
