The Utility of Procalcitonin as a Biomarker to Limit the Duration of Antibiotic Therapy in Adult Sepsis Patients

Ronald S. Chamberlain, Brian J. Shayota, Carl Nyberg, Prasanna Sridharan

Department of Surgery, Saint Barnabas Medical Center, Livingston, USA.

DOI: 10.4236/ss.2014.58057                

Abstract

Introduction: With rising global antibiotic resistance, stewardship programs aimed at controlling multi-drug resistant (MDR) pathogens have begun to gain acceptance. These programs stress appropriate antibiotic selection, dosage and duration. A growing literature suggests serum procalcitonin (PCT) levels may be useful in guiding antibiotic duration and de-escalation. This report sought to evaluate the evidence-based data available from prospective randomized controlled trials (RCT) on the role of PCT in guiding reductions in antibiotic duration in adult sepsis patients. Methods: A comprehensive search of all published prospective RCT(s) on the use of PCT as a tool for guiding antibiotic therapy in adult sepsis patients was conducted using PubMed, Medline Plus and Google Scholar (2007-2013). Keywords searched included, “procalcitonin”, “sepsis-therapy”, “sepsis biomarker”, “antibiotic duration”, “drug de-escalation”, and “antimicrobial stewardship”. Results: Four RCT(s) involving 826 adult sepsis patients have evaluated the role of serum PCT levels to guide criteria for cessation of antibiotic therapy based either on specific PCT levels or PCT kinetics. Bouadma et al. (N = 621) stopped antibiotics when the PCT concentration was <80% of the peak PCT value, or the absolute PCT concentration was <0.5 μg/L. The PCT arm showed a 2.7-day reduction in antibiotics. Schroeder et al. (N = 27) discontinued antibiotics if clinical signs of infection improved and the PCT value decreased to <1 ng/mL or to <35% of the initial value within three days. The PCT arm had a 1.7-day reduction in antibiotics. Hochreiter et al. (N = 110) ceased antibiotics when the PCT decreased to <1 ng/mL, or to 25% - 35% of the initial value over three days if the value was >1 ng/mL. The PCT arm showed a 2-day reduction in antibiotics. Finally, Nobre et al. (N = 68) stopped antibiotics when PCT levels decreased by 90% or more from the initial value, but not prior to Day 3 (if baseline PCT measured <1 μg/L) or Day 5 (if baseline PCT measured ≥1 μg/L). The PCT arm showed a 4-day reduction in antibiotics. Overall, reduction of PCT levels to 10% - 35% of the initial concentration, to <80% of the peak PCT value, or to an absolute PCT value of <1 μg/L warranted antibiotic discontinuation 1.7 to 4 days earlier. No study reported a significant difference in mortality between the PCT arm and the control arm (p< 0.05). Conclusions: PCT-guided early cessation of antibiotic therapy in adult sepsis patients is associated with a significant decrease in antibiotic days, with no effect on overall mortality. Measurement of serum PCT levels may have a role in antimicrobial stewardship programs aimed at limiting antibiotic therapy duration, decreasing the selective pressure on drug-resistant bacterial strains and reducing hospital costs.

Keywords

Procalcitonin, Sepsis Therapy, Sepsis Biomarker, Antibiotic Duration, Antibiotic De-Escalation, Antimicrobial Stewardship

Conflicts of Interest

The authors declare no conflicts of interest.

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