title: Association between positive urine cultures and necrotizing enterocolitis in a large cohort of hospitalized infants.
abstract: OBJECTIVE
  We used a large research database to examine the association between urinary tract infections and necrotizing enterocolitis (NEC) in premature infants.
  
  
  METHODS
  This retrospective data analysis included infants ≤32week gestational age and ≤1500g at birth who had urine cultures obtained at one of 322 neonatal intensive care units managed by the Pediatrix Medical Group from 1997 to 2012. The primary outcome was a diagnosis of NEC within 7days after urine culture. We used multivariable conditional logistic regression conditioned on postnatal age and controlling for gestational age, inotropic support on the day of culture, and mechanical ventilation on the day of culture to evaluate the association between urine culture result and NEC.
  
  
  RESULTS
  We identified 25,816 infants who had 43,556 urine cultures obtained; 6586 (15.1%) of the cultures were positive. A diagnosis of NEC within 7days after culture was made in 334 (5.1%) of the 6586 positive cultures versus 1582 (4.3%) of the 36,970 negative cultures (p<0.01). On multivariable analysis, infants with any positive urine culture had increased risk of NEC (odds ratio [OR] 1.16, 95% confidence interval [CI] 1.02-1.31); the risk was higher when limited to Gram-negative organisms (OR 1.37, 95% CI 1.17-1.59). The risk of surgical NEC was increased in infants with any positive urine culture (OR 1.46, 95% CI 1.18-1.81) and was also higher when limited to Gram-negative organisms (OR 1.99, 95% CI 1.53-2.59).
  
  
  CONCLUSIONS
  Positive urine cultures were associated with increased risk of NEC within 7days of culture.
authors.affiliation: Department of Pediatrics, Duke University School of Medicine, Durham, NC, United States.
authors.forename: Leslie C
authors.initials: LC
authors.lastname: Pineda
authors.affiliation: Department of Pediatrics, Duke University School of Medicine, Durham, NC, United States; Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC, United States.
authors.forename: Christoph P
authors.initials: CP
authors.lastname: Hornik
authors.affiliation: Department of Pediatrics, Duke University School of Medicine, Durham, NC, United States.
authors.forename: Patrick C
authors.initials: PC
authors.lastname: Seed
authors.affiliation: Department of Pediatrics, Duke University School of Medicine, Durham, NC, United States.
authors.forename: C Michael
authors.initials: CM
authors.lastname: Cotten
authors.affiliation: Department of Pediatrics, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States.
authors.forename: Matthew M
authors.initials: MM
authors.lastname: Laughon
authors.affiliation: Department of Pediatrics, Duke University School of Medicine, Durham, NC, United States.
authors.forename: Margarita
authors.initials: M
authors.lastname: Bidegain
authors.affiliation: Pediatrix-Obstetrix Center for Research and Education, Sunrise, FL, United States.
authors.forename: Reese H
authors.initials: RH
authors.lastname: Clark
authors.affiliation: Department of Pediatrics, Duke University School of Medicine, Durham, NC, United States; Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC, United States. Electronic address: brian.smith@duke.edu.
authors.forename: P
authors.initials: P
authors.lastname: Brian Smith
mesh_terms: D020345:Enterocolitis, Necrotizing / Q000150:complications* / Q000382:microbiology; D005260:Female; D005865:Gestational Age; D006760:Hospitalization; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D012189:Retrospective Studies; D012307:Risk Factors; D014552:Urinary Tract Infections / Q000150:complications* / Q000382:microbiology
keywords: Necrotizing enterocolitis; Neonatal; Urinary tract infection