Safety and efficacy of CURB65-guided antibiotic therapy in community-acquired pneumonia

OBJECTIVES: To determine whether the introduction of a community-acquired pneumonia (CAP) severity assessment tool to guide antibiotic selection could reduce broad-spectrum antibiotic prescribing without compromising patient safety. METHODS: A prospective before and after evaluation study. Empirical antibiotic prescribing was studied for 18 months from June 2006 to January 2008 (pre-intervention) and then for 18 months following the implementation of a CURB65-guided antibiotic therapy guideline in June 2008. The primary outcome was the use of broad-spectrum antibiotics (cephalosporin, amoxicillin plus clavulanic acid and macrolides) in patients with CAP. Safety outcomes were 30 day mortality, requirement for mechanical ventilation and/or vasopressor support (MV/VS), development of complicated pneumonia, time to clinical stability (TCS) and length of hospital stay. RESULTS: The introduction of CURB65-guided therapy resulted in an overall reduction in the prescription of cephalosporins (from 27.1% of patients receiving this agent in the overall pre-intervention cohort to 8.0% in the post-intervention cohort, P < 0.0001) and macrolides (72.8% to 58.7%, P < 0.0001), particularly among low-risk patients. There was a corresponding increase in the prescription of the narrower-spectrum agent amoxicillin (29.7% to 41.7%, P < 0.0001) and an increase in the use of amoxicillin monotherapy (10.4% to 29.9%, P < 0.0001). Co-amoxiclav use increased slightly as this agent replaced cephalosporins as first-line treatment for severe CAP. The guideline had no impact on 30 day mortality, MV/VS, complicated pneumonia, TCS or length of stay. Following the intervention, adherence to national guidelines increased from 25.4% of prescriptions to 61.9%, suggesting the potential for further improvements. CONCLUSIONS: CURB65-guided antibiotic therapy was associated with a significant decrease in broad-spectrum antibiotic use. The intervention was safe with no impact on mortality, treatment failure or clinical response.