title: Composition of Escherichia coli population in the neonatal gut: phylogroups and virulence determinants.
abstract: The composition of Escherichia coli in the neonatal gut has rarely been studied in developing countries. To gain insight into the composition of E. coli in the neonatal gut and to assess factors that could influence colonization by E. coli, analysis of the phylogenetic groups and virulence determinants of E. coli isolated from the guts of neonates in a tertiary care hospital was carried out. The distribution of the phylogroups of 124 E. coli isolates recovered showed that phylogroups A (23 %) and B1 (49 %) accounted for 72 % of the isolates. Isolates of the phylogenetic group B2 were rare (8 %). Virulence factors were also rare with the exception of aerobactin (iucC), which was detected in 45 % of the isolates and was significantly associated with phylogroup B1. Multinomial logistic regression established that colonization with phylogroup B1 was associated with a stay in the neonatal intensive care unit; phylogroup A was associated with a stay on the ward; and phylogroups B2 and D were associated with neonates delivered vaginally. Evaluation of the effect of different E. coli phylogroups, with and without identified virulence determinants, on the gut of neonatal mice showed histopathological changes in the mucosa. The severity of the changes could be correlated with the presence of virulence determinants, irrespective of the phylogroup.
authors.affiliation: Division of Bacteriology, National Institute of Cholera and Enteric Diseases, P33, CIT Road, Scheme XM, Beliaghata, Kolkata 700010, India.
authors.forename: Parijat
authors.initials: P
authors.lastname: Das
authors.affiliation: Department of Neonatology, Institute of Post-Graduate Medical Education & Research and SSKM Hospital, Kolkata 700020, India.
authors.forename: Arun Kumarendu
authors.initials: AK
authors.lastname: Singh
authors.affiliation: Department of Neonatology, Institute of Post-Graduate Medical Education & Research and SSKM Hospital, Kolkata 700020, India.
authors.forename: Suchandra
authors.initials: S
authors.lastname: Mukherjee
authors.affiliation: Data Management, National Institute of Cholera and Enteric Diseases, P33, CIT Road, Scheme XM, Beliaghata, Kolkata 700010, India.
authors.forename: Krishnan
authors.initials: K
authors.lastname: Rajendran
authors.affiliation: Division of Electron Microscopy, National Institute of Cholera and Enteric Diseases, P33, CIT Road, Scheme XM, Beliaghata, Kolkata 700010, India.
authors.forename: Dhira Rani
authors.initials: DR
authors.lastname: Saha
authors.affiliation: Division of Bacteriology, National Institute of Cholera and Enteric Diseases, P33, CIT Road, Scheme XM, Beliaghata, Kolkata 700010, India.
authors.forename: Hemanta
authors.initials: H
authors.lastname: Koley
authors.affiliation: Division of Bacteriology, National Institute of Cholera and Enteric Diseases, P33, CIT Road, Scheme XM, Beliaghata, Kolkata 700010, India.
authors.forename: Sulagna
authors.initials: S
authors.lastname: Basu
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D004195:Disease Models, Animal; D004926:Escherichia coli / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D004927:Escherichia coli Infections / Q000473:pathology; D041981:Gastrointestinal Tract / Q000382:microbiology*; D005838:Genotype; D006801:Humans; D007231:Infant, Newborn; D007413:Intestinal Mucosa / Q000382:microbiology / Q000473:pathology; D051379:Mice; D010802:Phylogeny; D011446:Prospective Studies; D062606:Tertiary Care Centers; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D037521:Virulence Factors