Purpose : This study determined the prenatal and postnatal factors associated with complications
and prognosis in premature infants with leukemoid reaction.
Methods : We retrospectively reviewed the medical records of premature infants with
gestational ages <37 weeks and low birth weights (<2,500 g) who were admitted immediately
after birth to the neonatal intensive care unit at the Dongguk University Ilsan Hospital between
June 2005 and July 2006. A leukemoid reaction was defined as an absolute neutrophil count
(ANC) >30,000/mm3. The infants who had leukemoid reaction comprised the study group, while
the remainder of infants made up the control group. The relationships between maternal and
neonatal variables and ANC were studied.
Results : Leukemoid reaction was detected in 3.1% of the study infants (8 of 252). Factors more
frequently associated with infants with leukemoid reaction were as follows: maternal chorioamnionitis,
high levels of maternal and infant C-reactive protein, gestational age <37 weeks, birth
weight <2,500 g, low Apgar score, prolonged ventilator support, and a high incidence of bronchopulmonary
dysplasia (BPD). However, there were no significant differences with respect to the
antenatal usage of steroids, the incidences of patent ductus arteriosus, necrotizing enterocolitis,
intraventricular hemorrhage, retinopathy of prematurity, and mortality between the two groups.
Conclusion : Leukemoid reaction in premature infants was associated with chorioamnionitis
and high levels of serum C-reactive protein in mothers and infants, and BPD in infants. These
findings suggest that leukemoid reaction is secondary to inflammation caused by infection.
Purpose : This study determined the prenatal and postnatal factors associated with complications
and prognosis in premature infants with leukemoid reaction.
Methods : We retrospectively reviewed the medical records of premature infants with
gestational ages <37 weeks and low birth weights (<2,500 g) who were admitted immediately
after birth to the neonatal intensive care unit at the Dongguk University Ilsan Hospital between
June 2005 and July 2006. A leukemoid reaction was defined as an absolute neutrophil count
(ANC) >30,000/mm3. The infants who had leukemoid reaction comprised the study group, while
the remainder of infants made up the control group. The relationships between maternal and
neonatal variables and ANC were studied.
Results : Leukemoid reaction was detected in 3.1% of the study infants (8 of 252). Factors more
frequently associated with infants with leukemoid reaction were as follows: maternal chorioamnionitis,
high levels of maternal and infant C-reactive protein, gestational age <37 weeks, birth
weight <2,500 g, low Apgar score, prolonged ventilator support, and a high incidence of bronchopulmonary
dysplasia (BPD). However, there were no significant differences with respect to the
antenatal usage of steroids, the incidences of patent ductus arteriosus, necrotizing enterocolitis,
intraventricular hemorrhage, retinopathy of prematurity, and mortality between the two groups.
Conclusion : Leukemoid reaction in premature infants was associated with chorioamnionitis
and high levels of serum C-reactive protein in mothers and infants, and BPD in infants. These
findings suggest that leukemoid reaction is secondary to inflammation caused by infection.