Study of Factors Influencing the Dynamics of Colonisation and Decolonisation of the Digestive Tract by Clostridioides Difficile in Infants (BBDIFF)

Study of Factors Influencing the Dynamicsof Colonisation and Decolonisation of the Digestive Tract by Clostridioides Difficile in Infants

Clostridioides difficile (formerly C. difficile) is a bacterium found in the form of spores (a resistant form) to which patients may be exposed in a hospital environment. Once ingested, the spore can germinate in the digestive tract in its vegetative form (active form of the bacterium) and then takes on the appearance of a Gram-positive bacillus that colonizes the digestive microbiota. This preliminary stage of digestive colonization by the bacterium is facilitated by certain factors, in particular exposure to antibiotics, which disrupt the composition of the digestive microbiota (dysbiosis) and thus facilitate the establishment of C. difficile following the removal of the barrier effect of the digestive microbiota. Certain strains (known as "toxinogenic") are then able to produce the main virulence factors (toxins A (TcdA) and B (TcdB)), thereby causing the main clinical signs of digestive infection, particularly in patients with risk factors for C. difficile infection (elderly people, progressive cancer, immunodepression, etc.).The treatment of CDI is mainly based on the oral administration of anti-Clostridioides difficile antibiotics such as Fidaxomicin (FDX) or Vancomycin (VAN) for a period of 10 days, according to the European recommendations of the ESCMID and the American recommendations of the IDSA. Despite effective treatment, CDI is characterized by a high recurrence rate of up to 25% of cases, with multiple recurrences that can be particularly debilitating for patients. The effect of disruption of the gut microbiota (dysbiosis) following exposure to antibiotics can be explained by several non-exclusive hypotheses, such as the disappearance of protective bacterial species in the gut microbiota or, conversely, the appearance of bacterial species that favor the colonization of C. difficile.

Hospitalization, and more generally healthcare, has often been identified as a risk factor for CDI.Indeed, C. difficile is found ubiquitously in the environment and contaminates food products. It is still difficult to assess the frequency of contamination through the ingestion of contaminated food and the potential colonization of the host.

Only the composition of the gut microbiota appears to be an interesting avenue to explore, especially since it changes significantly during the first year of life as important events occur, including dietary diversification with the introduction of the first solid foods.

Study Overview

• Status: Not yet recruiting
• Conditions: Bacteria Infection Mechanism
• Intervention / Treatment: Other: cohort follow up

• Study Type: Interventional
• Enrollment (Estimated): 200
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

For mothers

• Women aged 18 or over who are pregnant
• Patients who have been informed and have consented to participate in the research
• Patient affiliated with a health insurance plan (beneficiary or dependent), For minor patients (children)
• unborn child
• at least one parent of the child included is French-speaking
• written consent from both parents for participation in the study criteria for non-inclusion parents under guardianship or trusteeship parents deprived of their liberty parents under judicial protection children born under X/or in foster care

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: cohort follow-up; The only intervention will be in women with a vaginal swab. For children, stool samples will be collected at specific points.	Other: cohort follow up; The only intervention will be in women with a vaginal swab. For children, stool samples will be collected at specific points.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
characterize the kinetics of digestive colonization and decolonization (clearance) by C. difficile in infants	characterize the kinetics of digestive colonization and decolonization (clearance) by C. difficile in infants from birth to 18 months of age.	18 months

Collaborators and Investigators

• Sponsor: Fondation Hôpital Saint-Joseph

Study record dates

Study Major Dates

• Study Start (Estimated): May 30, 2026
• Primary Completion (Estimated): May 31, 2029
• Study Completion (Estimated): December 31, 2029

Study Registration Dates

• First Submitted: March 27, 2026
• First Submitted That Met QC Criteria: April 3, 2026
• First Posted (Actual): April 6, 2026

Study Record Updates

• Last Update Posted (Actual): April 13, 2026
• Last Update Submitted That Met QC Criteria: April 7, 2026
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Keywords: characterize the kinetics of digestive colonization and decolonization (clearance) by C. difficile
• Other Study ID Numbers: 772_BBDIFF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No