Pathogenicity of Species of the Achromobacter Genus in Patients From Reunion Island With Cystic Fibrosis (ACHROMO-MUCO)

Pathogenicity of Species of the Achromobacter Genus in Patients With Cystic Fibrosis: a Prospective Multicentre Exploratory Study of a Cohort in Réunion Island.

The pathogenicity of Achromobacter bacteria is not yet well established, but studies show a decline in respiratory function and an increase in mortality associated with chronic colonisation (Tetart et al. 2019, Somayaji et al. 2017, Recio et al. 2018), making it possible to classify the Achromobacter genus as an emerging pathogen in cystic fibrosis. It is possible that certain species or clones are more virulent or resistant, requiring the adaptation of measures to prevent cross-transmission in the centres concerned.

However, until now, the identification of Achromobacter species has involved the use of molecular biology techniques that are not routinely applicable in diagnostic laboratories, limiting studies and the collection of epidemiological data. Recently, a database using MALDI-TOF mass spectrometry has been built for rapid and accurate species identification.

In view of the local epidemiology and the current lack of data, it would be necessary and interesting to use this tool to study a cohort of cystic fibrosis patients in Réunion island (North and South sites) to see whether one species has a greater clinical impact than another (pathogenicity), and/or is more responsible for chronic colonisation.

Study Overview

• Status: Recruiting
• Conditions: Cystic Fibrosis
• Intervention / Treatment: Other: Biological analyses

Detailed Description

The research hypotheses are: What is the pathogenicity of Achromobacter species in cystic fibrosis patients? Is the pathogenicity of one species of the genus Achromobacter greater than that of other species in cystic fibrosis patients, depending on the colonization status of this bacterial species? Colonization with a species of the genus Achromobacter is associated with an increased frequency of pulmonary exacerbations in cystic fibrosis patients.

We will therefore assess the frequency of pulmonary exacerbations as a function of the Achromobacter species colonizing/infecting cystic fibrosis patients.

As this is an exploratory study carried out mainly on bacterial strains from patients, it presents no risk to patients.

the results of the study will enable clinicians to improve their knowledge of the different species of bacteria in the Achromobacter genus, in terms of pathogenicity, ability to colonize the respiratory tract, resistance and virulence.

As far as patients are concerned, the knowledge gained from this study will help improve the overall management of their disease. It will also provide food for thought on the establishment of guidelines and recommendations for dealing with Achromobacter spp. colonization and therapeutic strategy.

• Study Type: Observational
• Enrollment (Estimated): 35

Contacts and Locations

• Study Contact: Name: Thomas GARRIGOS, Pharm D, PhD; Phone Number: +262 (0)2 62 90 62 67; Email: thomas.garrigos@chu-reunion.fr
• Study Contact Backup: Name: Bénédicte Artarit; Email: benedicte.artarit@chu-reunion.fr

Study Locations

• Réunion
  • Saint-Denis, Réunion
    • Recruiting
    • CHU la Réunion North
    • Contact: VERHILLE Juliette, MD; Email: Juliette.verhille@chu-reunion.fr
    • Principal Investigator: Juliette VERHILLE, MD
  • Saint-Pierre, Réunion
    • Recruiting
    • CHU la Réunion South
    • Contact: PERISSON Caroline, MD; Email: Caroline.perisson@chu-reunion.fr
    • Principal Investigator: Caroline PERISSON, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

Cohort of cystic fibrosis patients from Reunion island with Achromobacter spp colonisation

Description

Inclusion Criteria:

• Minor or major cystic fibrosis patients
• Patients with at least one sputum cytobacteriological test positive for Achromobacter spp. during the inclusion period.
• Patients living in La Réunion island.
• Patients for whom a non-opposition was obtained orally (if applicable from both one of the child's legal guardians and the child him/herself)

Exclusion Criteria:

• Patients without cystic fibrosis.
• Patients with cystic fibrosis but no Achromobacter-positive ECBC during the study inclusion period

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Frequency of pulmonary exacerbations according to the species of the Achromobacter genus colonising/infecting cystic fibrosis patients.	The occurrence of pulmonary exacerbations as a function of the species of the genus Achromobacter spp. Colonising/infecting patients.	2 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Frequency of pulmonary exacerbations as a function of Achromobacter spp. colonisation status.	The occurrence of pulmonary exacerbations according to the colonisation statuses defined according to the French National Diagnostic and Care Protocol (PNDS)-Mucoviscidose of the French National Authority for Health (HAS) July 2017.	2 years
Emergence or existing presence of clones within the species of the genus Achromobacter circulating among cystic fibrosis patients in Réunion, using genomic analyses.	Clonality between strains: whole genome sequencing with genotyping between strains	2 years
Presence of virulence factors in these strains using genomic analyses	Study of the virulome: whole genome sequencing in search of virulence genes	2 years
Search for genes responsible for antibiotic resistance by genomic analysis of these strains	Study of the resistome: whole genome sequencing in search of resistance genes, antibiotic sensitivity tests	2 years
To describe the epidemiology of Achromobacter spp. in cystic fibrosis patients in Réunion	Prevalence of chronic colonisation with Achromobacter spp. and prevalence of colonisation according to Achromobacter species	2 years

Collaborators and Investigators

• Sponsor: Centre Hospitalier Universitaire de la Réunion
• Investigators: Study Director: Thomas GARRIGOS, Pharm D, PhD, CHU La Réunion

Study record dates

Study Major Dates

• Study Start (Actual): February 29, 2024
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): March 1, 2027

Study Registration Dates

• First Submitted: April 2, 2024
• First Submitted That Met QC Criteria: April 12, 2024
• First Posted (Actual): April 17, 2024

Study Record Updates

• Last Update Posted (Actual): April 17, 2024
• Last Update Submitted That Met QC Criteria: April 12, 2024
• Last Verified: April 1, 2024

More Information

Terms related to this study

• Keywords: Achromobacter species; MALDI-TOF mass spectrometry; Réunion Island
• Additional Relevant MeSH Terms: Digestive System Diseases; Pathologic Processes; Respiratory Tract Diseases; Lung Diseases; Infant, Newborn, Diseases; Genetic Diseases, Inborn; Pancreatic Diseases; Fibrosis; Cystic Fibrosis
• Other Study ID Numbers: 2023/CHU/07

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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