Sepsis Research Analysis
March’s sepsis literature converged on rapid bedside phenotyping and biomarker-guided triage, biologically stratified immunomodulation, and host-directed therapeutics. A large pragmatic RCT showed that adding procalcitonin to ED triage reduced 28‑day mortality, while a prospective multicenter study operationalized 1-hour ARDS subphenotyping (IL‑6/sTNFR1 + bicarbonate) for precision enrollment. A validated three-biomarker ML score (PCT, sTREM‑1, IL‑6) quantified immune dysregulation and identifie
Summary
March’s sepsis literature converged on rapid bedside phenotyping and biomarker-guided triage, biologically stratified immunomodulation, and host-directed therapeutics. A large pragmatic RCT showed that adding procalcitonin to ED triage reduced 28‑day mortality, while a prospective multicenter study operationalized 1-hour ARDS subphenotyping (IL‑6/sTNFR1 + bicarbonate) for precision enrollment. A validated three-biomarker ML score (PCT, sTREM‑1, IL‑6) quantified immune dysregulation and identified hydrocortisone-responsive patients. Mechanistic host-pathogen work nominated a repurposable STAT1 axis for MRSA sepsis and mapped an ERβ–STOML2 acetylation pathway that drives macrophage pyroptosis, reinforcing host-directed strategies.
Selected Articles
1. Targeting phenol-soluble modulin α3-driven M1 macrophage polarization and necroptosis mitigates MRSA infection in mice.
Mechanistic work shows MRSA virulence factor PSMα3 drives M1 macrophage polarization and necroptosis via an ISGF3–necrosome axis downstream of FPR2. Pharmacologic STAT1 inhibition with the approved drug fludarabine reduced MRSA burden and improved outcomes in murine sepsis and pneumonia models, supporting host-directed anti-virulence strategies.
Impact: Identifies a targetable host–pathogen signaling axis and demonstrates efficacy with a repurposed, clinically available drug in sepsis-relevant models, accelerating translational prospects.
Clinical Implications: Supports adjunctive anti-virulence therapy development for MRSA sepsis; next steps include defining safety, dosing, and patient-selection biomarkers (e.g., PSMα3 activity) prior to human trials.
Key Findings
- PSMα3 triggers M1 polarization and necroptosis via ISGF3–necrosome interactions.
- FPR2 mediates PSMα3 effects; STAT1 is a central downstream node.
- Fludarabine (STAT1 inhibitor) reduced MRSA burden and improved survival in murine sepsis/pneumonia.
2. Procalcitonin testing combined with NEWS2 evaluation compared with usual care based on NEWS2 for identification of sepsis and antibiotic initiation in the emergency department in England and Wales (PRONTO): a multicentre, randomised, controlled, open-label, phase 3 trial.
A pragmatic multicentre phase 3 RCT (n=7,667) found that adding rapid procalcitonin testing to NEWS2 did not alter 3‑hour IV antibiotic initiation but reduced 28‑day mortality (13.6% vs 16.6%). Procalcitonin influenced clinician decision-making in ~65% of cases, indicating mortality benefit from biomarker-guided triage independent of immediate antibiotic timing.
Impact: Delivers high-quality evidence that a biomarker-guided ED workflow can reduce mortality, informing immediate implementation and stewardship strategies.
Clinical Implications: Consider implementing near-patient procalcitonin alongside NEWS2 with evaluation of adherence, antibiotic duration, and de-escalation; integrate into ED triage pathways with ongoing outcomes monitoring.
Key Findings
- No difference in 3-hour IV antibiotic initiation (48.4% vs 48.2%).
- Lower 28-day mortality with PCT-guided care (13.6% vs 16.6%; adjusted risk difference −3.12%).
- PCT altered clinical decisions in ~64.7% of cases; adverse events similar across groups.
3. Quantifying immune dysregulation in pneumonia and sepsis with a parsimonious machine-learning model: a multicohort analysis across care settings and reanalysis of a hydrocortisone randomised controlled trial.
A three-biomarker ML framework (procalcitonin, sTREM-1, IL-6) reproduced an immune dysregulation continuum (DIP/cDIP) originally defined by 35 biomarkers, validated across multiple external cohorts. Post-hoc RCT reanalysis showed hydrocortisone reduced mortality only in severely dysregulated patients, enabling biomarker-stratified immunomodulation.
Impact: Provides a validated, pragmatic tool to operationalize immune status and target immunomodulators to likely responders.
Clinical Implications: Adopt PCT/sTREM-1/IL-6 scoring to stratify sepsis patients for corticosteroids and other immunomodulators, with prospective validation in sepsis-specific RCTs.
Key Findings
- Three-marker model predicted DIP stage with ~91% accuracy and generalized across five external cohorts.
- Higher cDIP associated with increased mortality and secondary infections.
- Hydrocortisone reduced 30-day mortality only in severe dysregulation (DIP3 or cDIP ≥0.63).
4. Estrogen receptor β deficiency increases susceptibility to sepsis through metabolic reprogramming-induced macrophage pyroptosis.
Reduced ERβ expression in sepsis patients was linked mechanistically to fatty-acid-oxidation–driven acetyl-CoA accumulation and Stoml2 K221 acetylation, causing mitochondrial dysfunction and macrophage pyroptosis. Mutating Stoml2 K221 rescued mitochondrial function and improved survival in septic mice, nominating a druggable host-susceptibility axis.
Impact: Defines a concrete ERβ–immunometabolism–pyroptosis pathway with in vivo rescue, yielding biomarker and therapeutic leads for personalized sepsis care.
Clinical Implications: Evaluate ERβ as a susceptibility/prognostic marker and advance selective ERβ modulators or FAO/acetylation pathway inhibitors to prevent macrophage pyroptosis in high-risk patients.
Key Findings
- ERβ expression is reduced in sepsis and inversely correlates with severity.
- ERβ deficiency increases FAO and acetyl-CoA, acetylating Stoml2 K221, triggering mitochondrial dysfunction and pyroptosis.
- Stoml2 K221 mutation mitigates pyroptosis and improves survival in septic mice.
5. Bedside identification of subphenotypes in acute respiratory failure (PHIND): a multicentre, observational cohort study.
A prospective multicentre cohort (n=512) implemented a 1-hour near-patient assay (IL-6, sTNFR1) plus bicarbonate to classify ARDS/AHRF into hyper- vs hypoinflammatory subphenotypes with marked prognostic separation (60-day mortality 51% vs 28%). The study operationalizes rapid bedside subphenotyping suitable for precision enrollment.
Impact: First prospective demonstration that a 1-hour bedside panel can reproducibly stratify ARDS subphenotypes with large prognostic separation, enabling precision critical care.
Clinical Implications: ICUs can implement near-patient IL-6/sTNFR1 + bicarbonate to guide targeted therapies and trial enrollment; immediate operational planning and platform access are key.
Key Findings
- Near-patient IL-6/sTNFR1 with bicarbonate classified hyper- vs hypoinflammatory phenotypes within ~1 hour.
- Hyperinflammatory ARDS had markedly higher 60-day mortality (51% vs 28%; adjusted OR 2.7).
- Feasibility across 30 centers supports bedside precision stratification.