Distinct Fecal Microbiota Pattern Associated with Infant Bronchiolitis

By Christine Judge

Edited by Susan Sadoughi, MD, and André Sofair, MD, MPH

A gut microbiota dominated by Bacteroides is associated with elevated risk for bronchiolitis in infants, suggests a case-control study in Pediatrics.

Investigators matched 40 infants hospitalized with bronchiolitis with 115 healthy control patients (median age, 3 months), recruited from a primary care practice. Using fecal samples collected during hospitalization (cases) or at home prior to a clinic visit (controls), researchers conducted 16S rRNA gene sequencing to identify different microbiota profiles.

Four distinct microbiota profiles were identified: Escherichia-dominant (30%), Bacteroides-dominant (28%), Enterobacter/Veillonella-dominant (22%), and Bifidobacterium-dominant (21%). Following multivariable adjustment, the Bacteroides-dominant profile was significantly associated with increased risk for bronchiolitis, compared with the Enterobacter/Veillonella-dominant profile (odds ratio, 3.9).

Gut microbiota may modulate immune function in distant locations such as the respiratory tract, the authors note.

Dr. Louis M. Bell of NEJM Journal Watch Pediatrics and Adolescent Medicine comments: "The exciting aspect of this research is that the gut microbiota is modifiable. Based on the current study, one could imagine a day when pediatricians may prescribe specific diets and supplements (prebiotics and probiotics) that will protect infants against bronchiolitis."