The role of a DEdicated Infectious Disease consultant within an antimicrobial stewardship programme towards better patient CARE (DE-IDCARE Project): results from a quasi-experimental, single-centre study

Background: The DE-IDCARE project aimed to evaluate the impact of dedicated infectious disease consultations (CIDs) compared with traditional on-demand ID consultations (CODs) within a structured antimicrobial stewardship programme (ASP). Methods: A quasi-experimental, single-centre study included hospitalized patients in two high-risk settings (Emergency Surgery (ES) and post-neurosurgery intensive care units (NS-ICU)) receiving antimicrobial therapy during April–June 2023 (COD, pre-intervention, N = 117) and April–June 2024 (CID, post-intervention, N = 172). The CID model introduced tri-weekly systematic evaluations of all patients receiving antimicrobials. The intervention was assessed through 12 antimicrobial stewardship (AMS) indicators categorized into ID stewardship (ID-S), diagnostic stewardship (D-S) and therapeutic stewardship (T-S) and classified into optimal, nearly optimal, neutral, suboptimal and not optimal according to the difference in percentage between CID and COD. Antimicrobial consumption was analysed using the AWaRe classification and the DDD/100 days of hospitalization. New onset of multi-drug resistant (MDR) colonization as well as clinical outcomes were also evaluated. Results: CID led to significant improvements in the majority of AMS indicators, especially antimicrobial discontinuation in cases without infection (+46%), 48–72 h re-evaluation of antimicrobial therapy (+36%) and appropriate duration of treatment (+21.1%). The use of Watch and Reserve antibiotics was reduced. New onset of MDR colonization was also reduced, while clinical outcomes were similar to COD. Conclusion: The DE-IDCARE project underscores the potential of dedicated CIDs within a structured ASP, leading to optimization of antimicrobial prescriptions without significantly affecting patients' outcomes. These findings offer a strong rationale for the wider implementation of CID as a cornerstone of effective AMS strategies.