title: Gut microbiota in preterm infants with gross blood in stools: A prospective, controlled study.
abstract: OBJECTIVE
  Gross blood in stools is a peculiar entity in preterm infants, but little is known about its etiology. As gut microbiota can be distorted in preterm infants, we aimed to evaluate the gut microbiota in infants with gross blood in stools.
  
  
  METHODS
  In a prospective, controlled, single-center study, we enrolled all infants born before 34 weeks of gestational age presenting gross blood in stools that was either completely isolated or associated with mild clinical symptoms or radiological signs. Each case was paired with two controls who were hospitalized in the same unit and were matched for gestational age and birth weight. The diversity of the gut microbiota was analyzed using 16S rRNA gene PCR and temporal temperature gel electrophoresis. We calculated a diversity score corresponding to the number of operational taxonomic units present in the microbiota.
  
  
  RESULTS
  Thirty-three preterm infants with gross blood in stools were matched with 57 controls. Clinical characteristics were similar in cases and controls. There was no statistically significant difference in the diversity score between the two groups, but microbiota composition differed. The proportion of infants with Escherichia coli was significantly higher in cases than in controls (p=0.045) and the opposite pattern occurred for Staphylococcus sp. (p=0.047).
  
  
  CONCLUSIONS
  Dysbiosis could be a risk factor for gross blood in stools in preterm infants. Additional, larger studies are needed to confirm the implications of the presence of different genotypes of E. coli and to evaluate preventive actions such as the prophylactic use of probiotics and/or prebiotics.
authors.affiliation: Department of Neonatology, University Hospital Croix Rousse, Hospices Civils de Lyon, F-69004 Lyon, France; Faculty of Medicine of Tunis, University of Tunis El-Manar, 1007 Bab Saâdoun, Tunis, Tunisia.
authors.forename: Mohamed Ben
authors.initials: MB
authors.lastname: Said
authors.affiliation: Department of Neonatology, University Hospital Croix Rousse, Hospices Civils de Lyon, F-69004 Lyon, France; Rhone-Alpes Human Nutrition Research Center, F-69310 Pierre Bénite, France.
authors.forename: Stephane
authors.initials: S
authors.lastname: Hays
authors.affiliation: Department of Biostatistics, Hospices Civils de Lyon, F-69003 Lyon, France; CNRS, Laboratoire Biostatistique Santé, UMR 5558, F-69310 Pierre Bénite, France; Lyon-Sud Charles Merieux Medical School, Claude Bernard University Lyon 1, F-69310 Pierre Bénite, France.
authors.forename: Deplhine
authors.initials: D
authors.lastname: Maucort-Boulch
authors.affiliation: Department of Neonatology, University Hospital Croix Rousse, Hospices Civils de Lyon, F-69004 Lyon, France.
authors.forename: Abdallah
authors.initials: A
authors.lastname: Oulmaati
authors.affiliation: University Montpellier 1, Laboratoire de Bacteriologie-Virologie, EA 3755 UM1, Faculte de Pharmacie, F-34093 Montpellier, France.
authors.forename: Stefanyia
authors.initials: S
authors.lastname: Hantova
authors.affiliation: Department of Neonatology, University Hospital Croix Rousse, Hospices Civils de Lyon, F-69004 Lyon, France.
authors.forename: Claire-Marie
authors.initials: CM
authors.lastname: Loys
authors.affiliation: University Montpellier 1, Laboratoire de Bacteriologie-Virologie, EA 3755 UM1, Faculte de Pharmacie, F-34093 Montpellier, France; Department of Hospital Hygiene, CHU de Montpellier, F-34000 Montpellier, France.
authors.forename: Estelle
authors.initials: E
authors.lastname: Jumas-Bilak
authors.affiliation: Department of Neonatology, University Hospital Croix Rousse, Hospices Civils de Lyon, F-69004 Lyon, France; Rhone-Alpes Human Nutrition Research Center, F-69310 Pierre Bénite, France; Lyon-Sud Charles Merieux Medical School, Claude Bernard University Lyon 1, F-69310 Pierre Bénite, France. Electronic address: jean-charles.picaud@chu-lyon.fr.
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Picaud
mesh_terms: D016022:Case-Control Studies; D004926:Escherichia coli / Q000235:genetics*; D005243:Feces / Q000382:microbiology; D005602:France; D006471:Gastrointestinal Hemorrhage / Q000382:microbiology*; D041981:Gastrointestinal Tract / Q000382:microbiology*; D014644:Genetic Variation; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D011446:Prospective Studies; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013210:Staphylococcus / Q000235:genetics*
chemical_list: D012336:RNA, Ribosomal, 16S
keywords: Gut microbiota; Human milk; Infection; Prematurity; Rectal bleeding; Staphylococcus