title: Neonatal enteral feeding tubes as loci for colonisation by members of the Enterobacteriaceae.
abstract: BACKGROUND
  The objective of this study was to determine whether neonatal nasogastric enteral feeding tubes are colonised by the opportunistic pathogen Cronobacter spp. (Enterobacter sakazakii) and other Enterobacteriaceae, and whether their presence was influenced by the feeding regime.
  
  
  METHODS
  One hundred and twenty-nine tubes were collected from two neonatal intensive care units (NICU). A questionnaire on feeding regime was completed with each sample. Enterobacteriaceae present in the tubes were identified using conventional and molecular methods, and their antibiograms determined.
  
  
  RESULTS
  The neonates were fed breast milk (16%), fortified breast milk (28%), ready to feed formula (20%), reconstituted powdered infant formula (PIF, 6%), or a mixture of these (21%). Eight percent of tubes were received from neonates who were 'nil by mouth'. Organisms were isolated from 76% of enteral feeding tubes as a biofilm (up to 107 cfu/tube from neonates fed fortified breast milk and reconstituted PIF) and in the residual lumen liquid (up to 107 Enterobacteriaceae cfu/ml, average volume 250 mul). The most common isolates were Enterobacter cancerogenus (41%), Serratia marcescens (36%), E. hormaechei (33%), Escherichia coli (29%), Klebsiella pneumoniae (25%), Raoultella terrigena (10%), and S. liquefaciens (12%). Other organisms isolated included C. sakazakii (2%),Yersinia enterocolitica (1%),Citrobacter freundii (1%), E. vulneris (1%), Pseudomonas fluorescens (1%), and P. luteola (1%). The enteral feeding tubes were in place between < 6 h (22%) to > 48 h (13%). All the S. marcescens isolates from the enteral feeding tubes were resistant to amoxicillin and co-amoxiclav. Of additional importance was that a quarter of E. hormaechei isolates were resistant to the 3rd generation cephalosporins ceftazidime and cefotaxime. During the period of the study, K. pneumoniae and S. marcescens caused infections in the two NICUs.
  
  
  CONCLUSIONS
  This study shows that neonatal enteral feeding tubes, irrespective of feeding regime, act as loci for the bacterial attachment and multiplication of numerous opportunistic pathogens within the Enterobacteriaceae family. Subsequently, these organisms will enter the stomach as a bolus with each feed. Therefore, enteral feeding tubes are an important risk factor to consider with respect to neonatal infections.
authors.affiliation: School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham, NG11 8NS, UK. edward.hurrell@hotmail.com
authors.forename: Edward
authors.initials: E
authors.lastname: Hurrell
authors.forename: Eva
authors.initials: E
authors.lastname: Kucerova
authors.forename: Michael
authors.initials: M
authors.lastname: Loughlin
authors.forename: Juncal
authors.initials: J
authors.lastname: Caubilla-Barron
authors.forename: Anthony
authors.initials: A
authors.lastname: Hilton
authors.forename: Richard
authors.initials: R
authors.lastname: Armstrong
authors.forename: Craig
authors.initials: C
authors.lastname: Smith
authors.forename: Judith
authors.initials: J
authors.lastname: Grant
authors.forename: Shiu
authors.initials: S
authors.lastname: Shoo
authors.forename: Stephen
authors.initials: S
authors.lastname: Forsythe
mesh_terms: D004750:Enteral Nutrition / Q000009:adverse effects / Q000295:instrumentation*; D004755:Enterobacteriaceae / Q000302:isolation & purification*; D004756:Enterobacteriaceae Infections / Q000382:microbiology*; D004866:Equipment Contamination; D005506:Food Contamination; D005516:Food Microbiology; D006801:Humans; D041943:Infant Formula; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D008826:Microbial Sensitivity Tests; D012307:Risk Factors