"Over the past four decades there has been an explosive increase in allergy and asthma in westernized countries, which correlates with widespread use of antibiotics alterations and gastrointestinal (GI) microflora," says Mairi Noverr, a researcher on the study. "We propose that the link between antibiotic use and dysregulated pulmonary immunity is through antibiotic-induced long term alterations in the bacterial and fungal GI microflora."
Noverr and colleagues treated mice with a short course of antibiotics for 5 days to weaken the naturally occurring bacteria in the GI tract before experimentally introducing the yeast Candida albicans. Increased growth of C. albicans is a common side effect of antibiotic therapy. The mice were then exposed to mold spores. Those that had received antibiotic therapy and C. albicans colonization in the GI tract had increased hypersensitivity in the pulmonary tract compared with untreated mice.
"The studies presented here are the first direct demonstration that antibiotic therapy can promote the development of an allergic airway response," says Noverr. "While it remains to be tested whether human allergies result from altered microflora, we have demonstrated in an animal model that antibiotic use can promote the development of an airway allergic response following allergen exposure via the nose," says Noverr.
This release is a summary of a presentation from the 104th General Meeting of the American Society for Microbiology, May 23-27, 2004, in New Orleans, Louisiana. Additional information on these and other presentations at the 104th ASM General Meeting can be found online at http://www.