Prevalence of Discordant Procalcitonin Use at an Academic Medical Center.

Objectives: Despite multiple trials demonstrating that procalcitonin (PCT) is an effective tool for antibiotic stewardship, inconsistent application in real-world settings continues to fuel controversy regarding its clinical utility. We sought to determine rates of concordance between PCT results and antibiotic prescribing in hospitalized patients.

Methods: We performed a retrospective review of all inpatient encounters at an academic tertiary care health system with a PCT result between February 2017 and October 2019. Concordant prescribing was defined as starting or continuing antibiotics following an elevated PCT (>0.5 ng/mL) finding and withholding or stopping antibiotics following a low PCT (< 0.1 ng/mL) finding.

Results: Antibiotic prescribing decisions were discordant from the PCT level in 32.5% of our sample. Among patients not receiving antibiotics at the time of testing, 25.9% (430 of 1,662) were prescribed antibiotics despite a low PCT result. Among patients already receiving antibiotics, treatment was continued despite a low PCT level in 80.4% (728 of 906) of cases. Enhanced decision support tools introduced during the study period had no impact on PCT use for antibiotic decisions.

Conclusions: Overall concordance between PCT results and antibiotic use is relatively low in a real-world setting. The potential value of PCT for antibiotic stewardship may not be fully realized.