Support Tool for Antibiotic Allergy deLabeling (STAAL)

Impact Assessment of a Clinical Decision Support Tool for Non-invasive Antibiotic Allergy Label Delabeling and Refinement

Antibiotic allergy labels (AAL) are reported in 7% of inpatient's charts, especially for beta-lactams (86% of AAL, i.e., prevalence of 6%). They are associated with increased length of hospital stay, and use of second-line and broad-spectrum antibiotics. Allergy workups are able to invalidate the majority of these AAL but are time-consuming and require invasive skin and provocation testing. The investigators recently evaluated, for the first time in Europa, a strictly non-invasive delabeling protocol using a questionnaire, medical file search and contact with primary care health care workers in 200 adult internal medicine inpatients with a beta-lactam AAL. Up to half of the AAL could be removed or refined, demonstrating the potential of this strategy. In this project, they aim to assess the impact of using the non-invasive 'AAL-fact-check' tool in a multicenter study, on antibiotic selection, and clinical, antimicrobial, and economic endpoints, as compared with the standard of care (i.e., no AAL-fact-check tool).

Study Overview

• Status: Recruiting
• Conditions: Antibiotic Allergy
• Intervention / Treatment: Other: EPR search

• Study Type: Interventional
• Enrollment (Estimated): 3000
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Liesbeth Gilissen, PhD; Phone Number: +32 16 71 00 84; Email: liesbeth.gilissen@kuleuven.be

Study Locations

• Belgium
  • Leuven, Belgium
    • Recruiting
    • University Hospitals Leuven
    • Contact: Rik Schrijvers; Email: rik.schrijvers@uzleuven.be
    • Contact: Liesbeth Gilissen; Email: liesbeth.gilissen@kuleuven.be
    • Principal Investigator: Rik Schrijvers
    • Sub-Investigator: Liesbeth Gilissen
    • Sub-Investigator: Dries Wets

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Hospitalized patients
2. AAL for one or more beta-lactams

Exclusion Criteria:

1. Age younger than 18
2. Previous enrolment in this study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Non-Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: AAL fact-check; Semi-automated EPR search for re-exposure	Other: EPR search; A stored query in the EPR, that checks for re-exposure to the culprit antibiotic or class-member, from the date of AAL registration to the date of patient inclusion; Other Names: AAL-fact-check tool
No Intervention: Standard of care (no AAL fact-check)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
First line antibiotic use: yes (1)/no (0)	First line and/or narrow-spectrum beta-lactam antibiotic use (depending on the index indication, and following the guidelines of the Belgian Antibiotic Policy Coordination Commission BAPCOC), as a binary outcome.	Until 100 days after discharge

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Antibiotic allergy label removed: yes (1)/no (0)		Until 100 days after discharge
Antibiotic allergy label refined: yes (1)/no (0)		Until 100 days after discharge
Beta-lactam antibiotic tolerance: yes (1)/no (0)		Until 100 days after discharge
Need to switch antibiotics: yes (1)/no (0)		Until 100 days after discharge
Days until clinical recovery (days)		Until 14 days after discharge
In-hospital mortality: yes (1)/no (0)		Until 14 days after discharge of discharge/death
3 months post-hospitalization mortality: yes (1)/ no (0)		Until 14 days after discharge
Length of hospital stay (days)	Calculated as (date of discharge) - (date of admission) + 1	Until 14 days after discharge
Admission to ICU: yes (1)/no (0)		Until 14 days after discharge
Readmission within 3 months after discharge: yes (1)/no (0)		Until 100 days after discharge
Colonization with MRSA: yes (1)/no (0)		Until 100 days after discharge
Infection with MRSA: yes (1)/no (0)		Until 100 days after discharge
Colonization with VRE: yes (1)/no (0)		Until 100 days after discharge
Infection with VRE: yes (1)/no (0)		Until 100 days after discharge
Colonization with C.Diff: yes (1)/no (0)		Until 100 days after discharge
Infection with C.Diff: yes (1)/no (0)		Until 100 days after discharge
Cost of antibiotic treatment (euro)		Until 14 days after discharge
Cost of hospitalization (euro)		Until 14 days after discharge
Time needed to perform the AAL fact-check (minutes)	AAL fact-check procedure will be timed by the investigator	Until 14 days after discharge
Cost of human resources needed for AAL-fact-check (euro)		Until 14 days after discharge

Collaborators and Investigators

• Sponsor: Universitaire Ziekenhuizen KU Leuven
• Collaborators: AZ Turnhout; AZ Herentals; Heilig Hartziekenhuis, Mol; Noorderhart Pelt; Sint-Jozefskliniek Izegem
• Investigators: Principal Investigator: Rik Schrijvers, MD, PhD, Universitaire Ziekenhuizen KU Leuven

Study record dates

Study Major Dates

• Study Start (Actual): March 10, 2025
• Primary Completion (Estimated): December 1, 2025
• Study Completion (Estimated): May 1, 2026

Study Registration Dates

• First Submitted: December 20, 2024
• First Submitted That Met QC Criteria: January 10, 2025
• First Posted (Actual): January 13, 2025

Study Record Updates

• Last Update Posted (Actual): December 16, 2025
• Last Update Submitted That Met QC Criteria: December 15, 2025
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Keywords: clinical decision support; electronic health records; beta-lactam; drug allergy; Penicillin allergy; Delabeling; Antibiotic allergy
• Additional Relevant MeSH Terms: Chemically-Induced Disorders; Drug-Related Side Effects and Adverse Reactions; Drug Hypersensitivity
• Other Study ID Numbers: S68439

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No