Clinical trial NCT06602869: Cellular Markers in Treated or Untreated Non-tuberculous Mycobacterial Respiratory Infection in Patients With Cystic Fibrosis
Official title: Cellular Markers During a Non-tuberculous Mycobacterial Respiratory Infection, Treated or Untreated, in Patients With Cystic Fibrosis
Study type: OBSERVATIONAL
Overall status: NOT_YET_RECRUITING
Conditions: Non-Tuberculous Mycobacterial Pneumonia
Keywords: Cystic Fibrosis
Interferon gamma release assay
Diagnostic Test
Lead sponsor: University Hospital, Montpellier
Sponsor class: OTHER
Collaborators: name: Hôpital Cochin
name: Cystic Fibrosis Foundation
First posted: 2024-09-19
Enrollment: 76
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_CONTROL
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Adult patients with cystic fibrosis included in the CIMeNT study (N°ID RCB : 2017-A00025-48)

Brief summary: This study evaluates a diagnostic serological test for Non-Tuberculous Mycobacteria (NTM) infection in cystic fibrosis patients by measuring T cell response. It aims to highlight a dynamic response associated to the pathogen's presence. This multicenter case-control study involves two populations, providing a better understanding of the circulating T-IFNγ-MNT response in these patients.

Detailed description: Background: Evidence shows that Non-tuberculous Mycobacterial (NTM) infections have increased and are 1,000 to 8,000 times more frequent in patients with cystic fibrosis compared to the general population. The diagnosis is based on clinical, radiological, and microbiological criteria. Unfortunately, the first two criteria lack specificity, and microbiological detection of NTM is limited due to frequent sputum contamination by other pathogens in cystic fibrosis patients. Given these factors and the high incidence of NTM infections in this population, alternative diagnostic methods are necessary.

Aim: This study aims to validate an innovative diagnostic test based on the IGRA (Interferon-Gamma Release Assay) method, which measures T lymphocyte response to Interferon gamma (IFNγ). The test will be conducted on a subset of patients selected from the CIMeNT cohort (ID-RCB: 2017-A00025-48). This cohort consists of cystic fibrosis patients whose NTM infection prevalence has been previously assessed.

Method: This research is a multicenter case-control study. It includes two groups: a case group of patients with positive serological and/or microbiological responses indicating NTM infection, and a control group of patients without such responses. The test measures the host's immune response by evaluating circulating T cell activity. Specifically, it measures IFNγ release when T cells are in contact with NTM antigens. This method provides more informative diagnostics of NTM infection dynamics compared to serology or microbiology, which have known technical limitations.

The study involves a single visit, which is part of the routine care for cystic fibrosis patients. During this visit, a routine blood draw will be performed and an additional 7 ml tube will be collected.

Eligibility criteria: Inclusion Criteria:

* Patient ≥18 years
* Patient previously included in the CIMeNT study
* Patient with a confirmed diagnosis of cystic fibrosis regardless of CFTR genotype
* Patient affiliated to the social security system
* Patient registered in the French Cystic Fibrosis Registry
* Adult patient capable of spontaneous expectoration or after induction

Exclusion Criteria:

* Lung transplant patients
* Person placed under judicial protection
* Pregnant and breastfeeding women

Primary outcomes:
measure: Determination of interferon-gamma release assay
timeFrame: day 1 (V1)
Secondary outcomes:
measure: Evaluation of T lymphocyte response
timeFrame: day 1 (V1)
Other outcomes:
Locations:
Study officials:
affiliation: University Hospital, Montpellier
name: Raphael CHIRON, MD
role: PRINCIPAL_INVESTIGATOR
References: