Related Experiment Video
Updated: May 13, 2026

Multiplex Therapeutic Drug Monitoring by Isotope-dilution HPLC-MS/MS of Antibiotics in Critical Illnesses
Published on: August 30, 2018
Clinical audit on antimicrobial stewardship effectiveness in reducing antimicrobial-resistant bacterial colonisation
Karen Mazzola1, Aliai Lanci1, Silvia Piva1
1Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy.
Background:
International guidelines support the One Health approach and recommend antimicrobial stewardship programmes (ASPs) in veterinary medicine. National data on antimicrobial-resistant bacterial colonisation rates (AMRb CR) in horses remain limited.
Objectives:
To evaluate the effectiveness of an ASP in reducing AMRb CR in a Veterinary Teaching Hospital using a clinical audit.
Study Design:
Clinical audit.
Methods:
In Autumn 2021 active AMR surveillance in Perinatology/Reproduction and Internal Medicine Units planned; January-July 2022-first audit cycle (A1); Autumn 2022-review and implementation of antimicrobial use and biosecurity policies; January-July 2023-re-audit (A2) after ASP application. In total, 328 hospitalised horses (foals and adults) were included. Nasal and rectal swabs collected at admission/birth and discharge/euthanasia/death were tested for methicillin-resistant Staphylococci (MRS), third-generation cephalosporins-resistant Gram-negative bacteria (3GCR-GNB) and carbapenem-resistant Gram-negative bacteria (CR-GNB). Fisher's exact test and Mann-Whitney U test evaluated differences in AMRb CR, antimicrobial use, and hospitalisation length between A1 and A2.
Results:
In A2, there was a significant reduction in overall AMRb CR (foals: OR = 0.27, 95% CI 0-0.87, p = 0.03; adults: OR = 0.39, 95% CI 0-0.77, p = 0.01), in MRS CR (foals: OR = 0.30, 95% CI 0-0.57, p < 0.001; adults OR = 0.42, 95% CI 0-0.83, p = 0.01), in 3GCR-GNB CR (adults: OR = 0.47, 95% CI 0-0.89, p = 0.02; total: OR = 0.53, 95% CI 0-0.87, p = 0.01), and in CR-GNB CR (foals: OR = 0.26, 95% CI 0-0.90, p = 0.03; total: OR = 0.24, 95% CI 0-0.78, p = 0.02). Highest priority critically important antimicrobials use decreased (foals: OR = 0.17, 95% CI 0-0.41, p < 0.001; total: OR = 0.20, 95% CI 0-0.43, p < 0.001), as did antibiotic treatment duration (foals: A1 7.75 ± 11.5, A2 3.70 ± 4.63 days, p < 0.001; adults:A1 3.70 ± 4.63, A2 0.74 ± 2.27 days, p = 0.04), and hospitalisation length (foals ≤30 days old: A1 18.1 ± 18.9, A2 9.77 ± 7.01 days, p = 0.05; total: A1 16.0 ± 15.1, A2 12.6 ± 11.4 days, p = 0.03).
Main Limitations:
Lack of genotypic analysis and exclusion of the surgery unit.
Conclusion:
This clinical audit confirms the effectiveness of the implemented ASP and supports its adoption in comparable veterinary settings.
Related Concept Videos
Clinical Significance of Antibiotic Resistance
Healthcare Associated Infections II: Preventive Measures
The best practices for preventing healthcare-associated infections include hand hygiene, patient risk...
Antimicrobial Effectiveness
