Procalcitonin as a biomarker to guide treatments for patients with lower respiratory tract infections

ABSTRACT

Introduction

Lower respiratory tract infections are amongst the main causes for hospital/intensive care unit admissions and antimicrobial prescriptions. In order to reduce antimicrobial pressure, antibiotic administration could be optimized through procalcitonin-based algorithms.

Areas covered

In this review, we discuss the performances of procalcitonin for the diagnosis and the management of community-acquired and ventilator-associated pneumonia. We provide up-to-date evidence and deliver clear messages regarding the purpose of procalcitonin to reduce unnecessary antimicrobial exposure.

Expert opinion

Antimicrobial pressure and resulting antimicrobial resistances are a major public health issue as well as a daily struggle in the management of patients with severe infectious diseases, especially in intensive care units where antibiotic exposure is high. Procalcitonin-guided antibiotic administration has proven its efficacy in reducing unnecessary antibiotic use in lower respiratory tract infections without excess in mortality, hospital length of stay or disease relapse. Procalcitonin-guided algorithms should be implemented in wards taking care of patients with severe infections. However, procalcitonin performances are different regarding the setting of the infection (community versus hospital-acquired infections) the antibiotic management (start or termination of antibiotic) as well as patient’s condition (immunosuppressed or in shock) and we encourage the physicians to be aware of these limitations.

KEYWORDS:

• Lower respiratory tract infections
• antimicrobial pressure
• procalcitonin
• antibiotic stewardship
• ventilator-associated pneumonia
• sepsis
• critical care

Article highlights

• Unnecessary antimicrobial pressure should be reduced, and PCT-guided antibiotic administration could help physician optimize antimicrobials prescription.

• In the context of suspected CAP, particularly in the setting of suspected or proven viral CAP, PCT may be useful to withhold antimicrobial treatment when the likelihood of bacterial infection is low: a serum PCT <0.25 μg/L should encourage physicians to withhold antibiotics

• In patients with CAP, we recommend the use of PCT-guided algorithms to stop antimicrobials when serum PCT is <0.25 μg/L or has decreased by 80% compared to its highest value.

• In case of HAP/VAP suspicion, PCT (single value or kinetics) has low diagnosis performances, and we do not recommend its use for the confirmation of bacterial HAP/VAP, and therefore to the start of antimicrobials.

• We recommend, in patients with HAP or VAP, the use of PCT-guided algorithms to stop antimicrobials when serum PCT is <0.5 μg/L or reduced by 80% compared to its highest value.

• PCT rise in ICU patients, with or without ongoing antibiotic therapy should not encourage antimicrobials escalation.

Declaration of interest

The authors have no 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. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose

Additional information

Funding

This paper was not funded.