Abstract: ObjectiveTo analyze the risk factors for brain injury in preterm infants with necrotizing enterocolits (NEC).MethodsThe retrospective study was conducted in preterm infants with NEC (Bell stage ≥Ⅱ) admitted to the neonatal intensive care unit, Children's Hospital of Fudan University during January 1st, 2012 to August 31st, 2017. The included patients were divided into positive cranial MRI group with white matter grades≥7 or grey matter grades ≥5 and negative group--the rest of the patients, according to MRI grades. Then compare the clinical characteristics between two groups to analyse the risk factors for brain brain injury in preterm infants with NEC. The fitting curve was used to determine the cutoff and the receiver operating characteristics curve (ROC) was used to evaluate the predictive value of risk factors for brain injury.ResultsA total of 110 preterm infants with NEC were enrolled, including 49 in MRI positive group and 61 in negtive group. There were no statistical difference in GA, BW, antenatal steroid use, Apgar 1 min, duration of mechanical ventilation, operation, onset age of NEC, C reaction protein (CRP) and blood culture within 24 h after NEC between the two groups（P>0.05）. However, the incidence of white blood cell (WBC) <4×109·L-1 or > 20 ×109·L-1 and platelet (PLT) level within 24 h after NEC, the rates of Bell stage Ⅲ and intestinal perforation were significantly different （P<0.05）. WBC < 4×109·L-1 or > 20 ×109·L-1 within 24 h after NEC(OR=4.3，95%CI：1.6-11.5) and intestinal perforation(OR=4.7，95%CI：1.3-17.4) were the independent risk factors for brain injury. The area under curve (AUC) of ROC was 0.722 when WBC ≤ 8×109·L-1, and the corresponding cutoff, sensitivity and specificity were 5.2×109·L-1, 68.4% and 71.1%, respectively. While WBC > 8×109·L-1, the AUC was 0.695 and the corresponding cutoff, sensitivity and specificity were 15.5×109·L-1, 61.1% and 77.1%, respectively.ConclusionThe change of WBC within 24 h after NEC and intestinal perforation consist the independent risk factors for brain injury in preterm infants with NEC. WBC < 5.2×109·L-1 or > 15.5×109·L-1 during the 24 h after NEC has certain value to predict brain injury.