Impact of PA-100 AST System Rapid Antibiotic Susceptibility Test on Antibiotic Prescription for Community-Acquired Urinary Tract Infections in Spanish Primary Care Settings

Background/Objectives: This intervention study compared the impact of the PA-100 AST System (PA-100) with the standard of care on antibiotic-prescribing behaviour for community-acquired urinary tract infections in a Spanish primary care setting. Methods: Women seeking care for symptoms of uncomplicated urinary tract infections were recruited based on the last digit of their regional personal identification number in a control (no PA-100 result available) or intervention (PA-100 result available) arm. Differences in antibiotic-prescribing behaviour were analysed using Fisher’s exact test, with the sample size powered to detect a change in prescription in ≥6% of patients. Results: Availability of the PA-100 revealed resistance to fosfomycin in 21.5% of confirmed infections. This significantly shifted prescription away from fosfomycin towards nitrofurantoin and amoxycillin/clavulanic acid (p < 0.001). In accordance with local guidelines, fosfomycin was the most frequently prescribed antibiotic in the control arm (65.9%), whereas a significantly lower rate (37.7%) was observed in the intervention arm. Conclusions: The PA-100 shows potential to support antimicrobial stewardship by enabling targeted antibiotic treatment at the first visit and improving care in primary care settings.