Community-acquired Pneumonia Due to Chlamydia Pneumoniae

NCT07679789 | Not Yet Recruiting DMC

• 1 other identifier: 0079_MIR_CHLAMPAC
• Study Type: observational
• Target: 200
• Locations: 1 country
• Sites: 1

Brief Summary

This international retrospective Franco-Swiss study focuses on community-acquired pneumonia (CAP) caused by Chlamydia pneumoniae. The working hypothesis is that the prevalence of C. pneumoniae pneumonia is overestimated by the medical community. The primary objective is to determine the true prevalence of C. pneumoniae infections among patients with pneumonia who underwent simplex or multiplex PCR testing. Secondary objectives include;

1. 1.Outpatient management
2. 2.Hospitalization in a medical ward
3. 3.Admission to the intensive care unit
4. 4.In-hospital mortality
5. 5.Radiological presentation of patients with community-acquired pneumonia (CAP) caused by Chlamydia pneumoniae
6. 6.Prevalence of viral or bacterial co-infections associated with C. pneumoniae CAP

Conditions

Community-Acquired Pneumonia

Keywords

Chlamydia pneumoniae; Community-acquired pneumonia; Prevalence; PCR; Co-infection; Respiratory infection; Atypical pneumonia

Outcome Measures

Primary Outcomes (1)

• Prevalence of Chlamydia pneumoniae Among Pneumonia Cases Tested by PCR

  Proportion of pneumonia cases with a positive simplex or multiplex PCR for Chlamydia pneumoniae among all patients who underwent respiratory PCR testing during the study period.

  January 2015 to December 2025

Secondary Outcomes (5)

• Clinical Severity of Chlamydia pneumoniae Pneumonia

  From hospital admission through hospital discharge (up to 90 days)

• Radiological Characteristics

  Baseline (at the time of pneumonia diagnosis)

• Viral Co-Infection Rate

  Baseline (at the time of PCR testing)

• Bacterial Co-Infection Rate

  Baseline (at the time of PCR testing)

• Length of Hospital Stay

  From hospital admission through hospital discharge (up to 90 days)

Eligibility Criteria

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

Study Population

The study population consists of pediatric and adult patients from participating French and Swiss centers who had a positive simplex or multiplex PCR result for Chlamydia pneumoniae on an upper or lower respiratory tract specimen between January 2015 and December 2025. Eligible patients must have a documented diagnosis of pneumonia and available clinical data allowing characterization of disease presentation, management, radiological findings, co-infections, and outcomes. Patients who objected to the use of their medical data for research purposes or who did not have pneumonia are excluded.

You may qualify if:

• Positive simplex or multiplex PCR for Chlamydia pneumoniae on an upper or lower respiratory tract specimen between January 2015 and December 2025.
• Availability of clinical data allowing confirmation of pneumonia diagnosis.

You may not qualify if:

• Patient opposition to the use of medical data for research purposes.
• Absence of pneumonia diagnosis.
• Insufficient clinical data for analysis.

Sponsors & Collaborators

• Centre Hospitalier de Saint-Denis: lead

Study Sites (1)

Centre Hospitalier de Saint-Denis

Saint-Denis, 93200, France

Location

Related Publications (4)

• Garin N, Hugli O, Genne D, Greub G. Lack of Chlamydia-related bacteria among patients with community-acquired pneumonia. New Microbes New Infect. 2015 Oct 22;8:164-5. doi: 10.1016/j.nmni.2015.10.002. eCollection 2015 Nov. No abstract available.

  PMID: 27257497 RESULT

• Garin N, Marti C, Skali Lami A, Prendki V. Atypical Pathogens in Adult Community-Acquired Pneumonia and Implications for Empiric Antibiotic Treatment: A Narrative Review. Microorganisms. 2022 Nov 24;10(12):2326. doi: 10.3390/microorganisms10122326.

  PMID: 36557579 RESULT

• Miyashita N. Atypical pneumonia: Pathophysiology, diagnosis, and treatment. Respir Investig. 2022 Jan;60(1):56-67. doi: 10.1016/j.resinv.2021.09.009. Epub 2021 Nov 5.

  PMID: 34750083 RESULT

• Cunha BA. The atypical pneumonias: clinical diagnosis and importance. Clin Microbiol Infect. 2006 May;12 Suppl 3:12-24. doi: 10.1111/j.1469-0691.2006.01393.x.

  PMID: 16669925 RESULT

MeSH Terms

Conditions

Community-Acquired Pneumonia; Coinfection; Respiratory Tract Infections; Pneumonia, Mycoplasma

Condition Hierarchy (Ancestors)

Community-Acquired Infections; Infections; Pneumonia; Respiratory Tract Diseases; Mycoplasma Infections; Mycoplasmatales Infections; Gram-Negative Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Pneumonia, Bacterial; Lung Diseases

Central Study Contacts

Yacine Tandjaoui-Lambiotte, Principal Investigator

CONTACT

+33 1 42 35 61; yacine.tandjaouilambiotte@ch-stdenis.fr

Clinical Research Unit Coordinator Clinical Research Unit Coordinator, GHT Plaine de France Clinical

CONTACT

+33 1 42 35 61 40; coordination.rechercheclinique@ghtpdfr.fr

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 24, 2026
• First Posted: July 1, 2026
• Study Start: June 1, 2026
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): June 1, 2027
• Last Updated: July 1, 2026

Record last verified: 2026-06

Locations

FR (1)