Association of Dysbiosis and Immune Response in Bronchiolitis in Under 12 Months -Old Infants

Not Applicable

Recruiting

• Conditions: Bronchiolitis
• Interventions: Other: Sampling

• Registration Number: NCT06161285
• Lead Sponsor: Assistance Publique - Hôpitaux de Paris

Brief Summary

Acute bronchiolitis is a common disease in children under the age of two, caused mainly by the respiratory syncytial virus (RSV). Furthermore, given the same medical history, it is still very difficult to predict the course and severity of the infection at the onset of symptoms, Some studies have highlighted the importance of the microbiota (intestinal, oral or nasopharyngeal) and of the immune response to RSV in children, We will include 80 children under 2 years old with hospitalized bronchiolitis and non-hospitalized bronchiolitis. Oral, nasal and stool samples will be taken to study the various microbiota in search of dysbiosis. A capillary blood sample will be taken for immune studies.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2023-11-30
• Study First Submitted QC: 2023-11-30
• Study First Posted: 2023-12-07
• Study Start: 2024-12-06
• Status Verified: 2025-01
• Last Update Submitted: 2025-02-24
• Last Update Posted: 2025-02-26
• Primary Completion: 2026-03
• Study Completion: 2026-04

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 120

Inclusion Criteria

• Infants <12 months
• With bronchiolitis during RSV epidemic season
• No chronic illness
• No bronchiolitis medical history
• Signed consent from parents or legal guardians

Exclusion Criteria

• Chronic respiratory illness
• Medical history of bronchiolitis or newborn asthma
• Treatment with immunosuppressants
• Patient with no social security affiliation

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Severe bronchiolitis	Sampling	venous blood samples. Buccal, nasopharyngeal and rectal swabs
Non-hospitalized bronchiolitis	Sampling	Capillary blood samples. Buccal, nasopharyngeal and rectal swabs

Primary Outcome Measures

Name	Time	Method
Dysbiosis	Inclusion	comparison of the quantitative and qualitative composition of bacteria (alpha diversity, beta diversity, Shannon and Simpson index) in the digestive and nasopharyngeal microbiota

Secondary Outcome Measures

Name	Time	Method
Measurement of innate and adaptive responses by quantification of cytokines and chemokines in plasma	inclusion	Inflammatory/regulatory cytokines (IL1-\>17, IL-10, TGF-b, EGF, FGF-2, IFN-alpha, IFN-gamma, IFN-beta, MCRP-1 MCP-3, TNF-alpha...), cytokines of adaptative response (Th1, Th17, Th2 and/or Treg), markers of inflammatory response (interferon, TNFa, ...), quantified by Luminex
Identifying the mRNA profile in blood samples and nasal swabs	inclusion	mRNA will be identified by using RNA-Seq (Illumina)
Sequencing viral strains for mutation	Inclusion	Typing of respiratory syncytial virus-A (RSV-A) and B (RSV-B) and sequencing of strains (Amplicons)
Comparison of respiratory syncytial virus (RSV) antibodies levels on newborn screening specimen and on capillary swab during infection	Birth, Inclusion	Levels of RSV antibodies will be measured and compared between newborn screening specimen and capillary swab during infection
Study the load of Streptococcus pneumoniae (Sp) in RSV infections.	Inclusion	Compare the serotypic profiles of pneumococcus (Sp) present during RSV infections

Trial Locations

Locations (3)

Réanimation médico-chirurgicale Necker; 🇫🇷 Paris, France

APHP, Antoine Béclère Hospital; 🇫🇷 Clamart, France

AP-HP,Raymond Poincaré Hospital; 🇫🇷 Garches, France