Distortions in development of intestinal microbiota associated with late onset sepsis in preterm infants.
Late onset sepsis (LOS) is a major contributor to neonatal morbidity and mortality, especially in premature infants. Distortions in the establishment of normal gut microbiota, commensal microbes that colonize the digestive tract, might increase the risk of LOS via disruption of the mucosal barrier with resultant translocation of luminal contents. Correlation of distortions of the intestinal microbiota with LOS is a necessary first step to design novel microbiota-based screening approaches that might lead to early interventions to prevent LOS in high risk infants. Using a case/control design nested in a cohort study of preterm infants, we analyzed stool samples that had been prospectively collected from ten preterm infants with LOS and from 18 matched controls. A 16S rRNA based approach was utilized to compare microbiota diversity and identify specific bacterial signatures that differed in their prevalence between cases and controls. Overall α-diversity (Chao1) was lower in cases two weeks before (p<0.05) but not one week before or at the time of diagnosis of LOS. Overall microbiota structure (Unifrac) appeared distinct in cases 2 weeks and 1 week before but not at diagnosis (p<0.05). Although we detected few operational taxonomic units (OTUs) unique or enriched in cases, we found many OTUs common in controls that were lacking in cases (p<0.01). Bifidobacteria counts were lower in cases at all time points. Our results support the hypothesis that a distortion in normal microbiota composition, and not an enrichment of potential pathogens, is associated with LOS in preterm infants.
Department of Epidemiology, College of Public Health and Health Professions and College of Medicine and Emerging Pathogens Institute, University of Florida, Gainesville, FL, USA. vmai@ufl.edu
Volker
V
Mai
Roberto Murgas
RM
Torrazza
Maria
M
Ukhanova
Xiaoyu
X
Wang
Yijun
Y
Sun
Nan
N
Li
Jonathan
J
Shuster
Renu
R
Sharma
Mark Lawrence
ML
Hudak
Josef
J
Neu
D017668:Age of Onset; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use; D001644:Bifidobacterium / Q000187:drug effects / Q000302:isolation & purification; D015169:Colony Count, Microbial; D005243:Feces / Q000382:microbiology; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007422:Intestines / Q000187:drug effects / Q000382:microbiology* / Q000473:pathology; D008297:Male; D054892:Metagenome / Q000187:drug effects / Q000235:genetics*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D018805:Sepsis / Q000188:drug therapy / Q000382:microbiology* / Q000473:pathology; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents