Identification of Clinical, Genetic and Immunological Factors Involved in the Development of Severe Bacterial Infections in Pediatrics

NCT07111793 | Not Yet Recruiting

• 2 other identifiers: RC25_00612025-A01367-42
• Study Type: interventional
• Target: 1,401
• Locations: 1 country
• Sites: 6

Brief Summary

Severe bacterial infections (SBI) are responsible for significant morbidity and mortality in the paediatric population. There is considerable individual variability in children's susceptibility to developing SBIs. This variability is multifactorial, and the mechanisms at work are not yet fully understood. The investigators of this study therefore propose to study a population of children who had particularly severe bacterial infections requiring hospitalization in a pediatric intensive care unit in France between 2015 and 2018. This study is part of a global approach to understanding the mechanisms favoring the occurrence of IBS in pediatrics. The study will initially focus on analyzing the clinical phenotype of these children in terms of the type of infection presented, as well as immunologically with an immune workup of all these patients. The investigators also plan to contact each family individually to identify other episodes of personal or family IBS or other elements suggestive of immune deficiency (opportunistic infections, autoimmune manifestations, severe atopy). The investigators will also assess the persistent sequelae since their infectious episode, and their quality of life following this IBS. In parallel, the genetic analysis of these patients and their parents will be carried out using whole-exome sequencing. The investigators will compare the results with those obtained in 2 IBS-free control populations (N=70 and N=116). The goal is to identify genetic variants that favor the occurrence of IBS in general, and some that are specific to certain bacteria or clinical presentations.

Conditions

Severe Bacterial Infections

Keywords

Severe bacterial infections; Whole-exome sequencing; Inborn errors of immunity; pediatrics

Outcome Measures

Primary Outcomes (1)

• Identification of innate errors of immunity involved in the development of IBS in pediatrics.

  List of rare genetic variants significantly more frequently found in cases than in controls and/or absent in healthy parents.

  At the enrollment

Secondary Outcomes (6)

• Identification of inborn errors of immunity involved in the development of IBS and their association with abnormalities of the immune balance,

  At the enrollment

• Identification of rare genetic variants favoring certain clinical types of infection, or certain biological and immunological abnormalities.

  At the enrollment

• Identification of immune deficiencies in patients who have developed a severe bacterial infection

  At the enrollment

• Assessment of sequelae with the POPC sequelae score (Pediatric Overall Performance Category) at a distance from the IBS episode.

  At the enrollment

• Assessment of sequelae at a distance from the IBS episode with the Strengths and Weaknesses Questionnaire (SDQ-Fra).

  At the enrollment

Study Arms (2)

Patients with severe childhood bacterial infections

OTHER

Patient inclus dans l'étude DIABACT IV (NCT02167802) entre 2015 et 2018, dans les suites de son hospitalisation en réanimation pédiatrique en France pour une infection bactérienne sévère.

Other: Extended phenotyping; Other: Blood sample for WES; Other: Blood sample for PBMC freezing; Other: POPC score evaluation; Other: Questionnaire completion

Patient's biological parents

OTHER

Other: Blood sample for WES; Other: Questionnaire completion

Interventions

Extended phenotyping OTHER

Extended phenotyping (analysis performed at Nantes University Hospital, MANDATORY DELIVERY WITHIN 24 HOURS) = 1 EDTA 3 mL tube for patients included in Nantes.

Patients with severe childhood bacterial infections

Blood sample for WES OTHER

Blood sample for WES : 1 x 3 mL EDTA tube (if not included in DIABACT IV biocollection)

Patient's biological parents; Patients with severe childhood bacterial infections

Blood sample for PBMC freezing OTHER

Blood sample for PBMC freezing integrated into the biocollection: 1 EDTA tube = 3 mL

Patients with severe childhood bacterial infections

POPC score evaluation OTHER

Assessment of POPC score (Pediatric Overall Performance Category)

Patients with severe childhood bacterial infections

Questionnaire completion OTHER

Questionnaires completed by parents or children: * SDQ * PedSQL4.0

Patient's biological parents; Patients with severe childhood bacterial infections

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• For patients:
• Patient included in the DIABACT IV study between 2015 and 2018, following hospitalization in a pediatric intensive care unit in France for a severe bacterial infection.
• Patient affiliated to a social security system
• Written consent from legal representatives for participation in research. If one of the legal representatives is unable to complete/sign the written consent, it will be sought orally by telephone and recorded in the patient's file. If the patient is over 18, written consent will be obtained. If the patient is a minor, consent will be sought with communication adapted to his/her level of understanding and age.
• For parents:
• Patient's biological parents
• Written consent

You may not qualify if:

• Persons under court protection
• Refusal to participate in research

Sponsors & Collaborators

• Nantes University Hospital: lead

Study Sites (6)

Nantes University Hospital

Nantes, Loire Atlantique, 44093, France

Location

CHU de Brest

Brest, France

Location

Hospices Civils de Lyon

Lyon, France

Location

Hôpital Armand Trousseau

Paris, France

Location

Hôpital Necker enfants malades

Paris, France

Location

CHU de Saint-Étienne

Saint-Etienne, France

Location

MeSH Terms

Conditions

Bacterial Infections

Interventions

Blood Specimen Collection

Condition Hierarchy (Ancestors)

Bacterial Infections and Mycoses; Infections

Intervention Hierarchy (Ancestors)

Specimen Handling; Clinical Laboratory Techniques; Diagnostic Techniques and Procedures; Diagnosis; Punctures; Surgical Procedures, Operative; Investigative Techniques

Central Study Contacts

Elise LAUNAY

CONTACT

2 40 08 31 79; elise.launay@chu-nantes.fr

Sponsor Department

CONTACT

bp-prom-regl@chu-nantes.fr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 17, 2025
• First Posted: August 8, 2025
• Study Start: January 1, 2026
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): June 1, 2029
• Last Updated: January 26, 2026

Record last verified: 2025-12

Locations

FR (6)