Abstract: Background:Intestinal perforation in neonates with necrotizing enterocolitis（NEC） may lead to adverse neonatal outcomes. ObjectiveTo analyze the risk factors for intestinal perforation in neonates with necrotizing enterocolitis. Design:Casecontrol study Methods:The retrospective study was conducted in infants with NEC(Bell stage≥Ⅱ) admitted to the neonatal department, Children's Hospital of Chongqing Medical University during January 1st, 2011 to December 31st, 2021. The positive group was 153 NEC with intestinal perforation. By 1:1 random proportioning method,153 NEC with nonintestinal perforation were enrolled in negative group. The clinical characteristics between two groups were compared to analyze the risk factors for intestinal perforation in neonates with necrotizing enterocolitis. 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 intestinal perforation. Main outcome measures:The risk factors of intestinal perforation in neonates with necrotizing enterocolitis. Results:There were significant differences in birth weight, gestational age, small for gestational age infants, fever, hypotension, abdominal distension, bloody stools, thrombocytopenia, hypoproteinemia, hyperbilirubinemia, hypofibrinogenemia, renal impairment, coagulopathy, patent ductus arteriosus, proportion of ibuprofen usage before the diagnosis of NEC and proportion of dopamine usage within 1 week before the diagnosis of NEC in positive group and negative group(P＜0.05). Abdominal distension （OR=17.869，95%CI：4.97264.213）, blood in stool （OR=4.836，95%CI：1.77313.188）, thrombocytopenia （OR=16.657，95%CI：6.17344.943）, hyperbilirubinemia （OR=4.485，95%CI：1.80911.120）, hypofibrinogenia （OR=5.034，95%CI：1.50516.832）, sepsis （OR=12.385，95%CI：4.714~32.537）were the independent risk factors for intestinal perforation. ROC curve analysis showed that the combination of 6 independent risk factors and 6 risk factors had predictive value for intestinal perforation in neonates with necrotizing enterocolitis(P<0.05). The combination of the 6 independent risk factors mentioned above has the highest predictive value for intestinal perforation in neonates with necrotizing enterocolitis. The area under the curve of ROC was 0.961. Conclusions:Abdominal distension, blood in stool, thrombocytopenia, hyperbilirubinemia, hypofibrinogenia, sepsis were the independent risk factors for intestinal perforation.

Key words: Neonatal necrotizing enterocolitis, Intestinal perforation, Risk factors