title: Fecal microbiota in premature infants prior to necrotizing enterocolitis.
abstract: Intestinal luminal microbiota likely contribute to the etiology of necrotizing enterocolitis (NEC), a common disease in preterm infants. Microbiota development, a cascade of initial colonization events leading to the establishment of a diverse commensal microbiota, can now be studied in preterm infants using powerful molecular tools. Starting with the first stool and continuing until discharge, weekly stool specimens were collected prospectively from infants with gestational ages ≤32 completed weeks or birth weights≤1250 g. High throughput 16S rRNA sequencing was used to compare the diversity of microbiota and the prevalence of specific bacterial signatures in nine NEC infants and in nine matched controls. After removal of short and low quality reads we retained a total of 110,021 sequences. Microbiota composition differed in the matched samples collected 1 week but not <72 hours prior to NEC diagnosis. We detected a bloom (34% increase) of Proteobacteria and a decrease (32%) in Firmicutes in NEC cases between the 1 week and <72 hour samples. No significant change was identified in the controls. At both time points, molecular signatures were identified that were increased in NEC cases. One of the bacterial signatures detected more frequently in NEC cases (p<0.01) matched closest to γ-Proteobacteria. Although this sequence grouped to the well-studied Enterobacteriaceae family, it did not match any sequence in Genbank by more than 97%. Our observations suggest that abnormal patterns of microbiota and potentially a novel pathogen contribute to the etiology of NEC.
authors.affiliation: Department of Microbiology and Cell Sciences and Emerging Pathogens Institute, University of Florida, Gainesville, Florida, United States of America. vmai@ufl.edu
authors.forename: Volker
authors.initials: V
authors.lastname: Mai
authors.forename: Christopher Michael
authors.initials: CM
authors.lastname: Young
authors.forename: Maria
authors.initials: M
authors.lastname: Ukhanova
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Wang
authors.forename: Yijun
authors.initials: Y
authors.lastname: Sun
authors.forename: George
authors.initials: G
authors.lastname: Casella
authors.forename: Douglas
authors.initials: D
authors.lastname: Theriaque
authors.forename: Nan
authors.initials: N
authors.lastname: Li
authors.forename: Renu
authors.initials: R
authors.lastname: Sharma
authors.forename: Mark
authors.initials: M
authors.lastname: Hudak
authors.forename: Josef
authors.initials: J
authors.lastname: Neu
mesh_terms: D016022:Case-Control Studies; D020345:Enterocolitis, Necrotizing / Q000382:microbiology*; D005243:Feces / Q000382:microbiology*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007422:Intestines / Q000382:microbiology; D008297:Male; D054892:Metagenome