Implementation of an RT-PCR Assay for the Diagnosis of Rickettsia Spp. Infection

Rickettsia2024 is a multicenter, tissue observational, retrospective and prospective cohort study. Enrollment will take place within the outpatient clinics of the Infectious Diseases and Dermatology Unit of the IRCCS AOUBO and, following an infectious disease consultation in the Bologna Metropolitan area, at the Hospitals and CAUs of the Bologna Local Health Authority. Within these UUOOs, biopsy samples from normal clinical practice are performed on patients with strong clinical suspicion of Rickettsia infection: therefore, it will not be necessary to perform any additional samples for the conduct of this study. Samples from the normal diagnostic process are sent to the Microbiology UOC, where they are subjected to various analyses. RT-PCR analyses (commercial or in-house kit) and assay of species-specific IgG antibodies will be performed according to clinical practice. Additional tests will be performed with a commercial kit for retrospective samples and with a home-made method for prospective samples.

Study Overview

• Status: Not yet recruiting
• Conditions: Infection; Rickettsia Infections

Detailed Description

It is estimated that a total of approximately 800 patients can be recruited, 400 for the retrospective part and the same number for the prospective part (estimated using data collected from requests received to date). For the retrospective cohort: from January 2023 until approval by the ethics committee; For the prospective cohort: from ethics committee approval until December 2027.

• Study Type: Observational
• Enrollment (Estimated): 800

Contacts and Locations

• Study Contact: Name: Silvia Galli; Phone Number: +39 0512144450; Email: silvia.galli@aosp.bo.it
• Study Contact Backup: Name: Giulio Virgili, MD; Email: giulio.virgili@aosp.bo.it

Study Locations

• Italy
  • Bologna
    • Bologna, Bologna, Italy, 40138
      • IRCCS Azienda Ospedaliero-Universitaria di Bologna
    • Bologna, Bologna, Italy
      • AUSL di Bologna
      • Contact: Giulio Virgili; Email: giulio.virgili@aosp.bo.it

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Non-Probability Sample

Study Population

The study population will consist of patients belonging to the UUOOs involved in the study, for whom serum samples, whole blood, skin biopsy, eschar, vesicle buffer underlying the eschar collected through withdrawals that meet the inclusion criteria, performed according to clinical practice, are available:

• For the retrospective cohort: from January 2023 until approval by the ethics committee;
• For the prospective cohort: from ethics committee approval until December 2027. The Microbiology Unit is the operational reference unit. The Infectious Diseases and Dermatology Unit of the IRCCS AOUBO is involved in patient enrollment, as are the Hospitals and CAUs of the Bologna Local Health Authority, following requests for infectious disease counseling in the Bologna Metropolitan Area.

Description

Inclusion Criteria:

• pazienti che presentano escara
• pazienti con richiesta del dosaggio degli anticorpi anti-Rickettsia conorii

Exclusion Criteria:

• None

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
retrospective cohort
prospective cohort

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
To evaluate the early diagnostic capability of molecular testing (RT-PCR) for the diagnosis of Rickettsia infection at the time of first blood sampling in suspected cases.	from January 7, 2026 to June 7, 2028

Secondary Outcome Measures

Outcome Measure	Time Frame
Comparison of the sensitivity and specificity of diagnosis of in-house RT-PCR and commercial kit (Rickettsia spp REAL TIME PCR, Immunospark)	from January 7, 2026 to June 7, 2028
Identification of Rickettsia species by gene sequencing of the 16S rRNA portion of samples tested positive (threshold cycle < 30) by in-house RT-PCR/commercial kit	from January 7, 2026 to June 7, 2028
Estimation of the incidence of Rickettsia conorii infections in the Bologna metropolitan area through serological screening	from January 7, 2026 to June 7, 2028

Collaborators and Investigators

• Sponsor: IRCCS Azienda Ospedaliero-Universitaria di Bologna

Publications and helpful links

General Publications

• Giulieri S, Jaton K, Cometta A, Trellu LT, Greub G. Development of a duplex real-time PCR for the detection of Rickettsia spp. and typhus group rickettsia in clinical samples. FEMS Immunol Med Microbiol. 2012 Feb;64(1):92-7. doi: 10.1111/j.1574-695X.2011.00910.x. Epub 2011 Dec 12.
• Brouqui P, Bacellar F, Baranton G, Birtles RJ, Bjoersdorff A, Blanco JR, Caruso G, Cinco M, Fournier PE, Francavilla E, Jensenius M, Kazar J, Laferl H, Lakos A, Lotric Furlan S, Maurin M, Oteo JA, Parola P, Perez-Eid C, Peter O, Postic D, Raoult D, Tellez A, Tselentis Y, Wilske B; ESCMID Study Group on Coxiella, Anaplasma, Rickettsia and Bartonella; European Network for Surveillance of Tick-Borne Diseases. Guidelines for the diagnosis of tick-borne bacterial diseases in Europe. Clin Microbiol Infect. 2004 Dec;10(12):1108-32. doi: 10.1111/j.1469-0691.2004.01019.x.

Helpful Links

• Related Info
• Related Info

Study record dates

Study Major Dates

• Study Start (Estimated): January 7, 2026
• Primary Completion (Estimated): June 7, 2028
• Study Completion (Estimated): June 7, 2029

Study Registration Dates

• First Submitted: December 15, 2025
• First Submitted That Met QC Criteria: December 15, 2025
• First Posted (Actual): December 29, 2025

Study Record Updates

• Last Update Posted (Actual): December 29, 2025
• Last Update Submitted That Met QC Criteria: December 15, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Vector Borne Diseases; Bacterial Infections; Bacterial Infections and Mycoses; Gram-Negative Bacterial Infections; Rickettsiaceae Infections; Infections; Rickettsia Infections
• Other Study ID Numbers: Rickettsia2024

Drug and device information, study documents

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