Procalcitonin-Informed Decision-Making in Abdominal and Emergency Surgery: A WSES Position Paper

Background: Procalcitonin (PCT) may support decision-making in abdominal and emergency surgery when infection is difficult to distinguish from non-infectious inflammation. Its interpretation remains challenging because clinical settings, sampling schedules, and proposed thresholds vary. This WSES position paper examines the evidence across six clinical scenarios to provide a practical framework for PCT-informed decision-making. Methods: A structured literature review covering January 1980 to December 2025, with targeted updates through August 2026, informed six PICO-based clinical questions. Evidence appraisal drew on selected GRADE domains, including consistency, directness, and precision. Recommendations were developed through iterative expert review and consensus. Results: The panel formulated six conditional recommendations addressing intra-abdominal infection diagnosis, antibiotic discontinuation after source control, suspected source-control failure, infected pancreatic necrosis, infectious complications after trauma, and postoperative anastomotic leak. The panel's qualitative assessment rated evidence certainty as moderate for antibiotic discontinuation and the pancreatitis domain, and low for the remaining domains. Serial PCT trends may complement clinical assessment in selected patients. Evidence for reduced antibiotic exposure with predefined PCT algorithms is more established than evidence that PCT-informed imaging, reintervention, or discharge decisions improve patient outcomes. Conclusions: PCT-informed decision-making in abdominal surgery may contribute to a more individualized approach to emergency surgical care and precision emergency surgery. When interpreted as part of serial assessment and integrated with clinical judgement, organ-dysfunction trends, microbiology, imaging, and evaluation of source-control adequacy, PCT may support individualized antibiotic discontinuation, potentially earlier recognition of an unfavourable clinical course, and more timely diagnostic and source-control reassessment. Current evidence does not support universal thresholds or routine serial testing in all surgical patients. Biomarker kinetics should strengthen, but not replace, surgical reasoning or independently determine antimicrobial, imaging, or interventional decisions. Future research should validate setting-specific thresholds and sampling schedules, establish whether PCT provides actionable information before clinical deterioration, and evaluate the clinical effects and cost-effectiveness of PCT-informed pathways.