Carbapenemase-Producing Enterobacterales (CPE) Colonization
Conditions
Keywords
Healthcare-Associated Infections, Antimicrobial Resistance, Enterobacteriaceae Infections, Nosocomial Colonization, Infection Control
Brief summary
Purpose: Carbapenemase-producing Enterobacterales (CPE) are a growing cause of healthcare-associated infections, linked to high morbidity, mortality, and cost. Current screening methods rely mainly on culture, which can take up to 48 hours and delay infection control actions. This study aims to evaluate the real-life impact of implementing a rapid PCR-based algorithm for CPE detection compared with the standard culture-based protocol, focusing on time differences in isolation and de-isolation decisions in hospitalized patients. Design: A quasi-experimental, before-and-after, retrospective study conducted at Hospital Italiano de Buenos Aires (HIBA). Primary Outcome: Time (in hours) between rectal swab request and change in isolation status (application or removal of isolation label) before and after PCR implementation. Population: Adult patients (≥18 years) admitted between October 2023-April 2024 (pre-intervention) and October 2024-April 2025 (post-intervention), who had contact isolation initiated or discontinued based on CPE surveillance results. Rationale: The introduction of rapid molecular testing could reduce operational delays and unnecessary isolation days, optimizing resource use in a setting with high CPE endemicity.
Detailed description
Background: Carbapenemase-producing Enterobacterales (CPE) are critical-priority pathogens associated with increased morbidity, mortality, and healthcare costs. Screening and isolation are recommended infection control measures, yet delays inherent to culture-based methods can hinder timely decision-making and overuse limited isolation rooms. Objective: To compare the time to initiation and discontinuation of contact isolation-from swab request to result availability and isolation status update-before and after implementing a rapid PCR-based diagnostic protocol for CPE identification. Design and Setting: Retrospective, quasi-experimental before-after study at the Hospital Italiano de Buenos Aires, Argentina. The pre-intervention period covers October 1, 2023-April 30, 2024; the post-intervention period covers October 1, 2024-April 30, 2025. Intervention: Incorporation of real-time PCR testing (BD MAX™ System) for CPE genes (bla\_KPC, bla\_NDM, bla\_VIM/IMP, bla\_OXA-48-like) into the existing CPE surveillance and isolation reevaluation workflow. The infection control team coordinates sample requests and response actions. Primary Outcomes: Time difference (in hours) from surveillance swab request to isolation implementation. Time difference (in hours) from surveillance swab request to isolation discontinuation. Secondary Outcomes: Time differences stratified by weekday versus weekend. Time differences according to sampling time (08:00-16:00 vs 16:00-08:00). Time differences according to immunosuppression status. Time differences in ICU versus general ward settings. Data Collection: Four timestamps will be extracted from the electronic health record (EHR): swab request, laboratory check-in, final laboratory result, and change in isolation logo. These will allow computation of operational intervals (request → action), collection delay, processing delay, and action delay. Statistical Analysis: Continuous variables will be summarized as medians and interquartile ranges. Median time differences between pre- and post-intervention periods will be compared using mixed-effects linear regression adjusted for immunosuppression, ICU admission, day of the week, and public holidays. Analyses will be conducted using Stata v16. Ethical Considerations: The study is retrospective and minimal-risk, involving only secondary use of clinical data. It has been submitted to the CEPI (Comité de Ética de Protocolos de Investigación), Hospital Italiano de Buenos Aires (PRIISA 15728), with waiver of informed consent under CIOMS 2019 Guideline 10. Expected Impact: By quantifying real-time process improvements after PCR implementation, this study will provide evidence on diagnostic turnaround times and operational efficiency in infection control practices.
Interventions
DIAGNOSTIC_TESTRapid PCR-based algorithm for CPE detection
Implementation of a rapid real-time PCR-based diagnostic algorithm for the detection of carbapenemase-producing Enterobacterales (CPE) integrated into the institutional infection control workflow. The BD MAX™ System detects bla\_KPC, bla\_NDM, bla\_VIM/IMP, and bla\_OXA-48-like genes from rectal swabs. The infection control team manages the process from sample request to result-based isolation decision. The intervention began on November 6, 2024, upon availability of PCR supplies and reagents.
Sponsors
Hospital Italiano de Buenos Aires
Study design
Allocation
NON_RANDOMIZED
Intervention model
SEQUENTIAL
Primary purpose
DIAGNOSTIC
Masking
NONE
Intervention model description
This study follows a sequential, before-after interventional design. The same hospital population and inclusion criteria are applied in two consecutive periods: * Pre-intervention period: standard culture-based algorithm for carbapenemase-producing Enterobacterales (CPE) surveillance and isolation reevaluation. * Post-intervention period: implementation of a rapid PCR-based algorithm (BD MAX™ System) for CPE detection integrated into the same workflow. No randomization or masking is performed. The comparison evaluates real-life time differences in isolation and de-isolation processes before and after PCR implementation.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Adult patients aged ≥18 years * Patients screened for carbapenemase-producing Enterobacterales (CPE) carriage by perianal swab within the first 5 days of hospital admission * Patients newly identified as CPE-colonized, leading to initiation of contact isolation * Patients found to be decolonized, leading to discontinuation of contact isolation * Patients with indication for active surveillance at hospital admission: * Transfer from another healthcare facility * Hospitalization in another healthcare center within the previous month * Patients undergoing active surveillance during hospitalization: * First surveillance swab in high-risk neutropenic patients (HAR flag) * First surveillance swab in immunosuppressed units, such as hematopoietic stem-cell transplant wards * Patients evaluated for discontinuation of contact precautions who meet all of the following: * Prior CPE-positive surveillance sample * At least 3 months since the last positive result and last hospitalization * No systemic antibiotic exposure during that period
Exclusion criteria
* Lost samples * Insufficient samples * Invalid laboratory test results requiring repeat sampling
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Time from surveillance swab request to isolation implementation or discontinuation (hours) | From the date and time of electronic request for perianal swab collection until the date and time of isolation status update in the EHR, assessed up to 168 hours (7 days). | Primary Outcome Measure 1\. Operational time from surveillance swab request to isolation status change (hours) Description: Time elapsed between the electronic request for perianal surveillance swab (clinical suspicion) and the implementation or discontinuation of the carbapenemase-producing Enterobacterales (EPC) isolation logo in the electronic health record (EHR). Unit of Measure: Hours |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Sample collection delay (hours) | From the date and time of electronic request for perianal swab collection until laboratory check-in of the sample, assessed up to 72 hours. | Description: Time elapsed between the electronic request for perianal surveillance swab and laboratory check-in of the sample. Unit of Measure: Hours |
| Laboratory processing delay (hours) | From the date and time of laboratory check-in until the date and time of final laboratory result, assessed up to 96 hours. | Time elapsed between laboratory check-in of the perianal swab sample and availability of the final laboratory result. Unit of Measure: Hours |
| Action delay after laboratory result (hours) | From the date and time of final laboratory result until the date and time of isolation status update in the EHR, assessed up to 72 hours. | Time elapsed between availability of the final laboratory result and update of the EPC isolation status (logo) in the electronic health record. Unit of Measure: Hours |
Contacts
CONTACTEmilio Felipe Huaier Arriazu, MD
Outcome results
None listed