Procalcitonin in Antimicrobial Stewardship: Clinical Utility Across Infections and Healthcare Settings

Antimicrobial resistance (AMR) is a mounting global health threat, largely driven by the overuse and misuse of antibiotics. Procalcitonin (PCT), a biomarker that rises in bacterial infections, has gained attention as a tool for optimizing antibiotic use within antimicrobial stewardship programs (ASPs). This review explores the clinical utility of PCT in guiding antimicrobial decisions across diverse infections and healthcare settings, including intensive care units (ICUs), emergency departments, outpatient clinics, and special patient populations. PCT has demonstrated value in differentiating bacterial from non-bacterial infections, guiding the initiation and discontinuation of antibiotics, and reducing unnecessary antibiotic exposure. In ICU settings, randomized trials such as PRORATA and SAPS have shown that PCT-guided protocols can safely reduce antibiotic duration without compromising patient outcomes. In emergency and outpatient care, PCT supports decision-making in respiratory tract infections and exacerbations of chronic conditions, improving prescribing practices. In immunocompromised, pediatric, and renal patients, PCT shows promise but requires cautious interpretation. Integration of PCT into ASPs has shown positive impacts but faces barriers including cost, clinician confidence, and variability in implementation. PCT is a valuable adjunct to clinical judgment in antimicrobial stewardship, enabling targeted and judicious antibiotic use. Broader adoption of PCT-guided approaches, informed by clinical context and supported by stewardship infrastructure, may help curb AMR and enhance patient care.