Clinical trial NCT02884700: Severe Legionellosis Cases Admitted to Grenoble University Hospital, 2006-2011.
Official title: Molecular Epidemiology of Legionellosis in Grenoble Region
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Legionnaires' Disease
Keywords: Legionella
Legionnaires' disease
Diagnosis
Prognosis
Lead sponsor: University Hospital, Grenoble
Sponsor class: OTHER
First posted: 2016-08-31
Enrollment: 82
Sex: ALL
Minimum age (years): 18
Maximum age (years): 99
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: RETROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: 82 unrelated legionellosis cases 64 males, 18 females mean age: 55 years, range: 27-97 years severe legionellosis requiring hospitalization

Brief summary: The study aimed at further describing the epidemiological, clinical, diagnostic and prognostic features in legionellosis cases admitted to Grenoble University Hospital during the 2006-2011period. The investigators also tested lower respiratory samples collected from these patients during their routine medical care, using a number of molecular tools allowing determination of the involved Legionella species, the bacterial load, and the presence of antibiotic resistant mutants. Our primary goal was to define biological markers that could predict severity and outcome of infection in legionellosis cases requiring hospitalization.

Detailed description: Patients admitted to Grenoble University Hospital between 2006 and 2011 for severe legionellosis were retrospectively included in the study.

Clinical, epidemiological, diagnostic and prognostic data of these patients were recorded retrospectively.

Lower respiratory samples collected from these patients on a routine basis for microbiological analysis, especially Legionella culture, were tested using traditional microbiological methods. The remaining part of these samples was stored at -80°C fur further molecular analyses.

The molecular tools developed by our bacteriology laboratory included the following: a real-time polymerase chain reaction (qPCR) test allowing detection and differentiation of L. pneumophila and other Legionella species; a qPCR test allowing determination of the Legionella DNA load in lower respiratory samples; a qPCR allowing detection of gyrA (the gene encoding subunit A of DNA gyrase) mutations that the investigators previously determined to be correlated with fluoroquinolones resistance in L. pneumophila; a high-throughput sequencing approach allowing confirmation of gyrA mutations and determination of the percentage of mutated alleles.

The microbiological data, especially those obtained with the developped molecular tools, were tentatively correlated with the severity and outcome of infection in our patients' cohort.

Eligibility criteria: Inclusion Criteria:

* age higher than 18 years
* proven legionellosis case (positive culture and/or PCR and/or urinary antigen test)
* severe case requiring hospitalization

Exclusion Criteria:

* age under 18 years
* pregnant women

Primary outcomes:
measure: Legionella DNA load in lower respiratory tract samples
timeFrame: through study completion, an average of 1 year
Secondary outcomes:
measure: Fluoroquinolones resistant gyrA mutants in lower respiratory tract samples
timeFrame: through study completion, an average of 1 year
Other outcomes:
Locations:
Study officials:
affiliation: Direction of Research and Medical Innovation (DRCI)
name: Hélène Sabbah-Guillaume, Director
role: STUDY_DIRECTOR
References: