Perinatal factor and neonatal outcome of very low birth weight infants with leukemoid reaction

Lee, Hyun Ju; Kim, Eun Sun; Shim, Gyu Hong; Choi, Chang Won; Kim, Ee Kyung; Kim, Han Suk; Kim, Beyong Il; Choi, Jung Hwan

Abstract

PURPOSE:Leukemoid reaction (LR) represents inflammatory reaction in very low birth weight (VLBW) infants, and has been reported to relate with the development of bronchopulmonary dysplasia (BPD). This study was done to assess the relationship between perinatal characteristics and neonatal outcome of leukemoid reaction in VLBW infants.
METHODS
Three hundred and seventy two VLBW infants admitted to the NICUs of SNUCH and SNUBH between June 2005 to June 2008 were studied in a retrospective case-controlled manner. Of these VLBW infants, 32 LR (+) infants were compared with 83 LR (-) infants who were matched for gestational age and birth weight with respect to perinatal and neonatal clinical characteristics. LR was defined as a white blood cell (WBC) count of more than 40,000 cells/mm3 or absolute neutrophil count of more than 30.000 cells/mm3 during the first month of life.
RESULTS
Of 413 VLBW infants, There was no significant difference between the LR (+) and LR (-) infants in sex, Apgar scores, maternal peripheral WBC count, the use of antenatal steroids and maternal age. Comparing with LR (-) infants, LR (+) infants had a higher positive rate for amniotic fluid culture (67% vs 11%; P< or =0.01), U. ureaplasma in amniotic fluid (52% vs 10%; P=0.01), histologic chorioamnionitis (81% vs 33%; P=0.01) and funisitis (50% vs 7%; P=0.01). The incidences of respiratory distress syndrome, patent ductus arteriosus, necrotizing enterocolitis, sepsis, intraventricular hemorrhage and BPD showed no significant difference between LR (+) and LR (-) infants.
CONCLUSION
LR during the first month of life in VLBW infants was associated with chorioamnionitis, but not with the incidence of bronchopulmonary dysplasia or other neonatal morbidities. These findings suggest that LR may be a simple reflection of transient accelerated neutrophil production induced by prenatal inflammation without significant neonatal consequences.