Dynamics of Upper and Lower Airway Respiratory Microbiomes Associated With Severe Infant Asthma (Microbiosthme)

Dynamique Des Microbiomes Respiratoires Des Voies supérieures et inférieures associée à l'Asthme sévère Des Nourrissons

The aim of this project is to establish the nature of potential dysbiosis, the interrelation of the different microbiomes of the respiratory tract, and the potential role of the immune system in the pathogenesis of severe asthma in infants, and its evolution under treatment. The aim of exploring and understanding these data is to ultimately improve patient care and discover new therapeutic targets. Indeed, modification of the microbiota was a therapeutic target even before it was discovered, and its immunomodulatory properties reinforce this position. The aim is to open up prospects for therapeutic studies, such as the use of azithromycin as an immunomodulator in infant asthma, the results of which are discordant.

A nasopharyngeal swab will be collected at inclusion and at each follow-up visit after an induced sputum

Inclusion Criteria: Infants less than 24 months old Follow-up by a pneumo-pediatrician for severe asthma in infants Requiring etiological investigations and assessment of severity in day hospitalization, including bronchial fibroscopy (HAS 2009) Parent informed of the research and having signed consent Exclusion Criteria: Prematurity <32 WA Congenital heart disease with significant left to right shunt Chronic respiratory disease other than infant asthma (cystic fibrosis, bronchiolitis obliterans) Antibiotic therapy in progress or administered the seven days preceding the date of inclusion (day hospitalization) Refusal of bronchial fibroscopy