Role of procalcitonin in bacteremic patients and its potential use in predicting infection etiology

ABSTRACT

Introduction: Bloodstream infections (BSI) and their evolution to sepsis or septic shock are one of the most important causes of morbidity and mortality; for this reason, arapid recognition and diagnosis of these infections are crucial to improve patients’ outcome.

Area covered: Procalcitonin (PCT) is considered an important biomarker for diagnosis of infection, routinely used to identify patients developing severe bacterial infections. In this scenario, management of BSI is complicated by the increasing rate of multidrug-resistantstrains, and an early recognition of severe infections is mandatory. Moreover, an appropriate use and prescription of antibiotics is important to reduce the risk of development of further antibiotic resistances.

Expert opinion: we reviewed recent literature about the use of PCT in bacteremic patients to determine its role to predict infections, severity of clinical condition and antibiotic therapy duration; its role was defined in many studies to reduce duration of antibiotic treatment, especially in critically ill patients and for lower respiratory tract infections. Moreover, we reported recent studies in which PCT showed ahigh performance to detect precociously infections due to Gram-negativestrains. Data from the literature confirm that PCT should not be used as astand-alonetest in the absence of clinical judgment.

KEYWORDS:

• Procalcitonin
• C-reactive protein
• bacteremia
• Gram-negative
• Enterobacteriaceae

Article highlights

• PCT levels increase rapidly in plasma during inflammation, faster than the other acute inflammatory biomarkers.

• PCT values were directly associated with the development of severe infections and/or lower respiratory tract infections.

• The usefulness of PCT in clinical practice is not definitively recognized, considering also the high costs and the lack of a point of care test that limit its spread. Recent randomized trials reported different conclusions about its use to guide antibiotic decisions and to reduce unnecessary administration of antimicrobial therapy.

• Recent data reported the association between PCT values and GN etiology, especially Enterobacteriaceae. On this basis, we can hypothesize a potential role for PCT in predicting etiology of infections, especially in critically ill patients.

• In this scenario, the use of algorithms based on PCT values may drive physicians to a more appropriate choice of antibiotic regimes, while awaiting for definitive microbiological results, and decision to stop therapy.

Declaration of interest

In the past five years M Bsssetti has participated in advisory boards and/or received speaker honoraria from Achaogen, Angelini, Astellas, AstraZeneca, Bayer, Basilea, Cidara, Gilead, Melinta, Menarini, MSD, Nabriva, Paratek, Pfizer, Roche, The Medicine Company, Shionogi, Tetraphase, VenatoRX, and Vifor. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript.

Reviewer disclosures

A reviewer on this manuscript has disclosed that they have received support from biomarker companies in the past. Peer reviewers on this manuscript have no other relevant financial relationships or otherwise to disclose.

Additional information

Funding

This paper was not funded.