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Early intestinal Bacteroides fragilis colonisation and development of asthma

Carl Vael1, Vera Nelen, Stijn L Verhulst

  • 1Department of Microbiology, University of Antwerp, Antwerp, Belgium. carl.vael@zna.be

BMC Pulmonary Medicine
|September 30, 2008
PubMed

Insights

Early intestinal colonization with Bacteroides fragilis in infants may indicate a higher risk of developing asthma. This finding highlights the importance of the gut microbiome in early childhood immune development and asthma prediction.

Area of Science:

  • Microbiology
  • Immunology
  • Pediatrics

Background:

  • The hygiene hypothesis posits that reduced microbial exposure increases atopic disease risk.
  • The gut microbiome plays a role in regulating the immune system's Th1/Th2 balance.
  • Early life microbial colonization is crucial for immune development.

Purpose of the Study:

  • To examine the link between early intestinal microbial colonization and asthma development in children.
  • To investigate if specific bacteria in infancy predict later asthma diagnosis.

Main Methods:

  • A prospective birth cohort study of 117 children was conducted.
  • Children were assessed using the Asthma Predictive Index (API).
  • Infant fecal samples at 3 weeks were cultured to identify bacterial colonization.

Main Results:

  • 22% of children had a positive API.
  • Bacteroides fragilis colonization was more prevalent in infants with a positive API (64% vs. 34%).
  • Higher counts of Bacteroides fragilis and Total Anaerobes at 3 weeks correlated with a positive API, showing a significant association (OR: 4.4).

Conclusions:

  • Bacteroides fragilis colonization at 3 weeks is an early predictor of potential childhood asthma.
  • This research may aid in targeted prevention and treatment strategies for asthma.
  • Modulating the early-life gut microbial environment could be key for asthma management.
Abstract

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