Airway Microbial Community Turnover Differs by BPD Severity in Ventilated Preterm Infants

• Published in: PloS one Vol. 12; no. 1; p. e0170120
• Main Authors: Wagner, Brandie D., Sontag, Marci K., Harris, J. Kirk, Miller, Joshua I., Morrow, Lindsey, Robertson, Charles E., Stephens, Mark, Poindexter, Brenda B., Abman, Steven H., Mourani, Peter M.
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 27.01.2017; Public Library of Science (PLoS)
• Subjects: Abundance; Age; Asthma; Bacteria; Bacterial diseases; Biology and Life Sciences; Birth Weight; Bronchopulmonary dysplasia; Bronchopulmonary Dysplasia - genetics; Bronchopulmonary Dysplasia - microbiology; Bronchopulmonary Dysplasia - pathology; Chronic obstructive pulmonary disease; Chronology; Communities; Congenital diseases; Development and progression; Dysplasia; Ecological monitoring; Ecology; Ecology and Environmental Sciences; Enrollments; Epidemiology; Female; Gastroenterology; Gestational Age; Health aspects; Humans; Infant, Newborn; Infant, Premature; Infants; Infections; Inflammation; Intubation; Intubation, Intratracheal - adverse effects; Lung - microbiology; Lung - pathology; Lung diseases; Lungs; Male; Medicine; Medicine and Health Sciences; Metadata; Microbial activity; Microbiomes; Microbiota; Microbiota (Symbiotic organisms); Microorganisms; Newborn babies; Oxygen; Pathogenesis; Pediatrics; People and Places; Pregnancy; Premature babies; Premature birth; Premature Birth - microbiology; Premature Birth - pathology; Premature infants; Public health; Relative abundance; Research and analysis methods; Respiration; Respiration, Artificial; Respiratory tract; Ribosomal DNA; RNA, Ribosomal, 16S - genetics; rRNA 16S; Staphylococcus; Staphylococcus - genetics; Staphylococcus - isolation & purification; Staphylococcus - pathogenicity; Studies; Trachea - microbiology; Trachea - pathology; Ureaplasma; Ventilation; Ventilators
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0170120

Preterm birth exposes the developing lung to an environment with direct exposure to bacteria, often facilitated by endotracheal intubation. Despite evidence linking bacterial infections to the pathogenesis of bronchopulmonary dysplasia (BPD), systematic studies of airway microbiota are limited. The objective was to identify specific patterns of the early respiratory tract microbiome from tracheal aspirates of mechanically ventilated preterm infants that are associated with the development and severity of BPD. Infants with gestational age ≤34 weeks, and birth weight 500-1250g were prospectively enrolled. Mechanically ventilated infants had tracheal aspirate samples collected at enrollment, 7, 14, and 21 days of age. BPD was determined by modified NIH criteria with oxygen reduction tests; infants without BPD were excluded due to low numbers. Aspirates were processed for bacterial identification by 16S rRNA sequencing, and bacterial load by qPCR. Cross-sectional analysis was performed using 7 day samples and longitudinal analysis was performed from subjects with at least 2 aspirates. Microbiome analysis was performed on tracheal aspirates from 152 infants (51, 49, and 52 with mild, moderate, and severe BPD, respectively). Seventy-nine of the infants were included in the cross-sectional analysis and 94 in the longitudinal. Shannon Diversity, bacterial load, and relative abundance of individual taxa were not strongly associated with BPD status. Longitudinal analysis revealed that preterm infants who eventually developed severe BPD exhibited greater bacterial community turnover with age, acquired less Staphylococcus in the first days after birth, and had higher initial relative abundance of Ureaplasma. In conclusion, longitudinal changes in the airway microbial communities of mechanically ventilated preterm infants may be associated with BPD severity, whereas cross-sectional analysis of airway ecology at 7 days of age did not reveal an association with BPD severity. Further evaluation is necessary to determine whether the observed longitudinal changes are causal or in response to clinical management or other factors that lead to BPD.