Clinical question: Can serum procalcitonin reliably detect bloodstream infections upon hospital admission?
Background: Hospitalists frequently manage patients with bacteremia, which is often associated with sepsis and an elevated mortality risk. Rapid initiation of treatment is crucial for improving outcomes. It is also imperative that we incorporate diagnostic stewardship into our decisions. The Surviving Sepsis Campaign has not previously supported procalcitonin use for sepsis diagnosis. This study wanted to look at the performance of procalcitonin for detecting bloodstream infections on admission in a real-world setting.
Study design: Retrospective, observational, cohort study
Setting: Cerner HealthFacts database, electronic health record data from 65 U.S. hospitals
Synopsis: This study looked at 74,958 patients at 65 U.S. hospitals, analyzing real-world data on the utilization of procalcitonin in patients admitted with potential bloodstream infections. They included patients 18 years or older who had blood cultures and procalcitonin ordered within 24 hours of admission. The procalcitonin cutoff used was 0.5 ng/mL for positivity. Procalcitonin levels differed by bloodstream pathogen and between disease severities. For detecting bloodstream infections overall, procalcitonin had a sensitivity of 68.2%, a specificity of 65.6%, a positive predictive value of 23.1%, and a negative predictive value of 93.2%. Although the negative predictive value was high, the authors note this should be interpreted with caution keeping in mind the prevalence of bloodstream infections and the possibility of pretreatment with antibiotics impacting blood culture results. Empiric antibiotic administration was similar despite negative or positive procalcitonin levels, and therefore testing did not influence the treatment decision.
Bottom line: The use of procalcitonin at a cutoff of 0.5 ng/mL on admission to detect bloodstream infections is not reliable given the risk of missed infection and the fact that procalcitonin results did not seem to alter the treatment decision for antibiotic administration.
Citation: Lawandi A, et al. Reliability of admission procalcitonin testing for capturing bacteremia across the sepsis spectrum: Real-world utilization and performance characteristics, 65 U.S. hospitals, 2008–2017. Crit Care Med. 2023;51(11):1527-37.
Dr. McCutcheon
Dr. McCutcheon is a hospitalist at Atrium Health in Charlotte, N.C.