Evaluating the utility of procalcitonin and a clinical decision support tool to determine duration of antimicrobial therapy for respiratory tract infections.

PURPOSE: Procalcitonin (PCT) levels may play a role in decreasing the duration of antimicrobial therapy in institutions that have long durations of therapy for management of community-acquired pneumonia. We assessed the impact of the combination of pharmacist stewardship interventions assisted by a clinical decision support (CDS) tool and PCT assessment on the antimicrobial days of therapy (DOT) prescribed for respiratory tract infections (RTIs). METHODS: We conducted a quasi-experimental study in which patients in the preintervention group were admitted between April and June 2021 and patients in the intervention group were admitted between April and June 2022. In the intervention phase, a CDS tool was utilized to alert clinical pharmacists when patients met specific criteria. This alert was programmed to activate for individual patients when a reported PCT level was less than 0.25 ng/mL and the patient was on antimicrobials prescribed for an RTI as indicated by providers in the electronic health record. Stewardship interventions were made by pharmacists via prospective audit and feedback. The primary endpoint was inpatient antimicrobial DOT for RTIs. RESULTS: There were 90 patients in the preintervention group and 104 patients in the intervention group. Although baseline characteristics were not well matched between the groups, favoring the preintervention group, the median DOT was lower in the intervention group, at 3 days (interquartile range [IQR], 2-4 days), compared to 4 days (IQR, 2.8-5 days) in the preintervention group (P = 0.001). CONCLUSION: The results of our study demonstrate the utility of pharmacist interventions coupled with CDS and PCT in reducing antimicrobial DOT prescribed for RTIs. Antimicrobial stewardship programs may benefit from implementing a PCT bundle.