In primary care, urinary tract infections (UTIs) account for the majority of antibiotic prescriptions. Comments from microbiologists on interpreting the antimicrobial susceptibility testing (AST) profile for urinalysis were made to improve the prescription of antibiotics. We aimed to explore the added value of these comments on the quality of antibiotic prescribing by a superior double-blind digital randomized case-vignette trial among French general practitioners (GPs). One case vignette with (intervention) or without (control) a ‘comment’ after AST was randomly assigned to GPs. Among 815 participating GPs, 64.7% were women, at an average age of 37 years. Most (90.1%) used a computerized decision support system for prescribing antibiotics. Empirical antibiotic therapy was appropriate in 71.9% (95% CI, 68.8–75.0) of the cases, without differences between arms. The overall appropriateness of targeted antibiotic therapy (primary outcome) was not significantly increased when providing ‘comments’: 83.4% vs. 79.9% (OR = 1.26, 95% CI, 0.86–1.85). With the multivariate analysis, the appropriateness was improved by 2-folds (OR = 2.38, 95% CI, 1.02–6.16) among physicians working in healthcare facilities. Among digital-affine young general practitioners, the adjunction of a ‘comment’ by a microbiologist to interpret urinalysis in community-acquired UTIs did not improve the overall level of appropriateness of the targeted antibiotic.

BACKGROUND Urinary tract infections account for most antibiotic prescriptions in primary care, with the use of broad-spectrum antibiotics and a high level of inappropriateness. Microbiologists are involved in antimicrobial stewardship programs and could help improve antibiotic prescribing through antimicrobial susceptibility reporting. OBJECTIVE To assess the added value of antimicrobial susceptibility testing (AST) comments issued by microbiologists on the quality of antibiotic prescriptions in community-acquired urinary tract infections (UTI). METHODS We conducted a superiority, double-blind, digital, randomized case-vignette study among French general practitioners (GP’s) between 11-24-2020 and 06-24-2021. Self-questionnaires containing one of the 6 case-vignette with or without comment were broadcasted via French general medical councils and regional residents’ unions. The primary outcome was the overall appropriateness of the antibiotic therapy prescribed according to last 2018 French guidelines for the management of community-acquired UTI. RESULTS Among 815 GP’s who responded to the questionnaire, 64,7% were women, with an average age of 37 years. Most of the GP’s (90,1%) used a Clinical Decision Support System. Empirical antibiotic therapy was appropriate in 71.9% (95CI, 68.8–75.0) of the cases, without differences between arms. The overall level of appropriateness for targeted antibiotic therapy did not differ with (83.4%) or without a comment (79.9%) (OR=1.26 (95CI, 0.86–1.85)). The appropriateness was the highest in asymptomatic bacteriuria in pregnant women (99.0%), and the lowest in indwelling urinary catheter-associated bacteriuria (52.9%). In multivariate analysis, only a hospital practice improved the appropriateness of the prescription by 2-folds (OR=2.38 (95CI, 1.02–6.16)). CONCLUSIONS In a young GPs’ population comments for antimicrobial susceptibility testing in UTI did not improve the appropriateness of targeted antibiotic prescription.