From Biomarkers to Bedside: Guiding Therapeutic Strategies in Refractory Septic Shock of Abdominal Origin

Septic shock of abdominal origin remains one of the most challenging conditions in critical care, with a substantial proportion of patients progressing to a refractory state despite adequate source control and standard resuscitative measures. Molecular biomarkers are established tools for early diagnosis and prognostic stratification and have been proposed as candidate tools for individualizing therapeutic decisions. This narrative review examines the evidence on biomarkers relevant to abdominal sepsis-associated septic shock—including procalcitonin, presepsin, lactate, interleukin-6 and gut-derived markers of intestinal barrier dysfunction—and examines how far they may inform the timing of source control, vasopressor escalation and the use of adjunctive therapies. Every marker is classified as diagnostic, prognostic, treatment-monitoring or predictive (treatment-selection), since a marker associated with outcome is not thereby a marker that predicts benefit from an intervention. We report turnaround time and availability for each assay, and the effect of acute kidney injury and kidney replacement therapy on its interpretation. The review offers a practical, evidence-informed framework and identifies the gaps that warrant investigation. No biomarker-guided strategy in this population has been prospectively validated; biomarkers remain adjuncts to clinical, radiological and surgical assessment and must never delay source control.