Daily Sepsis Research Analysis
Analyzed 47 papers and selected 3 impactful papers.
Summary
Analyzed 47 papers and selected 3 impactful articles.
Selected Articles
1. Enhanced autophagy drives endothelial tight junction loss, BBB disruption, and behavioral deficits during inflammation.
Using CLP and LPS models, the study shows that enhanced autophagy in brain endothelium drives tight junction loss and BBB disruption. Pharmacologic inhibition of autophagy (chloroquine, 3‑MA) preserved BBB integrity and reduced lethality, whereas induction (rapamycin) exacerbated leakage and mortality.
Impact: Identifies autophagy as a causal driver of BBB failure in sepsis with pharmacologic reversibility, offering a tractable target for sepsis-associated encephalopathy.
Clinical Implications: While preclinical, the data support testing autophagy modulation to prevent sepsis-associated encephalopathy and delirium, and to preserve neurovascular integrity in systemic inflammation.
Key Findings
- Proteomics of brain microvessels after CLP showed enrichment of autophagy–lysosome pathways and increased endothelial autophagic flux peaking at 24 h.
- LPS increased autophagic flux in bEnd.3 endothelial cells in a time- and dose-dependent manner.
- Autophagy inhibition (chloroquine or 3‑methyladenine) reduced BBB disruption and CLP-induced lethality; autophagy induction (rapamycin) worsened both.
Methodological Strengths
- Multi-system validation combining in vivo CLP/LPS models with in vitro endothelial assays and LC3 reporter imaging.
- Pharmacologic gain- and loss-of-function experiments linked to physiologic outcomes (BBB permeability, survival).
Limitations
- Preclinical murine and cell-line models without human validation.
- Reliance on pharmacologic inhibitors/inducers with potential off-target effects; limited cell-type–specific genetic manipulation reported.
Future Directions: Evaluate endothelial- or brain-targeted autophagy modulation in large-animal models and early-phase human studies of sepsis-associated encephalopathy with biomarker-guided selection.
The blood-brain barrier (BBB) protects the brain but becomes compromised during systemic inflammatory conditions such as sepsis. The mechanisms driving BBB disruption remain incompletely understood. Here, we identified a significant enrichment of the macroautophagy/autophagy-lysosome-related pathway in the upregulated proteome using quantitative proteomics on brain microvessels from mice after cecal ligation and puncture (CLP) that induces polymicrobial sepsis. CLP progressively induced autophagic flux in brain endothelial cells, peaking at 24 h post-procedure before subsiding. Similarly, an mRFP-GFP-LC3 reporter assay and immunoblotting showed that lipopolysaccharide (LPS) treatment increased autophagic flux in bEnd.3 cells in a time- and dose-dependent manner. Mice intraperitoneally (IP) injected with the autophagy inhibitors chloroquine (CQ) or 3-methyladenine (3-MA) were resistant to BBB disruption caused by CLP or IP injection of LPS, whereas those injected with the autophagy inducer rapamycin (Rapa) were more susceptible. CQ and 3-MA reduced, while Rapa increased, CLP-induced lethality in mice. These effects were confirmed
2. Testing the Transportability of Sepsis Subtypes to Patients With ARDS for Postdischarge Outcomes.
In 580 mechanically ventilated ARDS patients from the ROSE trial, both transported and de novo latent class subtypes were significantly associated with mortality and early readmissions. Classification agreement was modest overall but high at the extremes of risk, supporting pragmatic use for prognostic enrichment.
Impact: Demonstrates transportability and operationalization of sepsis-derived subtypes to ARDS with long-term prognostic signal, enabling precision follow-up and trial enrichment strategies.
Clinical Implications: ARDS survivors can be stratified using a parsimonious algorithm to identify high- and low-risk groups for targeted follow-up, rehabilitation, and trial design.
Key Findings
- Transported five-variable subtypes were significantly associated with 12-month mortality (p=0.027) and 3-month readmission (p=0.043).
- De novo LCA identified 5 subtypes associated with mortality at 3, 6, and 12 months (all p<0.001) and 3-month readmission (p=0.008).
- Agreement between transported and de novo classifications was 48% (kappa 0.361), with strong concordance at the lowest- and highest-risk extremes.
Methodological Strengths
- Secondary analysis of a well-characterized RCT cohort with standardized data collection (ROSE trial).
- Comparison of transported vs. de novo latent classes with random-effects modeling and multiple time-point outcomes.
Limitations
- Secondary analysis without intervention; causality cannot be inferred.
- Moderate agreement between methods limits interchangeability; external generalizability beyond ROSE may be constrained.
Future Directions: Prospective validation of assignment algorithms across diverse ARDS/sepsis cohorts and use for enrichment in adaptive trials targeting post-discharge outcomes.
BACKGROUND: Survivors of ARDS experience significant morbidity and mortality after hospital discharge. A latent class analysis (LCA) proposed 5 sepsis survivor subtypes that may be of use for ARDS patients as well, but did not include an operationalization algorithm for assigning patients to subtypes. RESEARCH QUESTION: Can the Taylor sepsis survivor subtypes be operationalized in an ARDS population, and does such operationalizations distinguish patients at varying risk of post-discharge mortality and readmission? STUDY DESIGN AND METHODS: We conducted a secondary analysis of adults with acute respiratory distress syndromes requiring mechanical ventilation enrolled in the Reevaluation of Systemic Early Neuromuscular Blockade (ROSE) trial. We compared two methods of operationalizing subtype to develop an assignment rule: transported subtypes based on an algorithm developed using five variables from the previously published derivation cohort, and de novo subtypes derived from a new latent class analysis (LCA). Random-effect logit models were used to estimate the association between subtype and the primary outcome of mortality at 12 months. RESULTS: 580 participants were assigned to five subtypes using the transported approach. In age-adjusted regression, transported subtype was significantly associated with mortality at 12 months (p=0.027) and readmission at 3 months (p=0.043). A de novo LCA identified 5 distinct subtypes as the optimal solution; subtypes were associated with mortality at 3, 6, and 12 months (p<0.001) and readmission at 3 months (p=0.008). Agreement between the two assignment methods was 48% (kappa 0.361), and concentrated in the lowest (134/145, 92.4%) and highest risk (44/44, 100%) groups. INTERPRETATION: Sepsis survivor subtypes can be transported and operationalized in ARDS patients. Different approaches to operationalization yield similar but not identical subgroups classifications. Both approaches assign individuals to groups that are significantly associated with patient-important outcomes among ARDS survivors. Optimal strategies to transport externally derived subtypes, versus internal rederivation, may depend on the specific use case.
3. Advancing antimicrobial therapy: evaluating the ASTar (Q-linea) System for rapid AST in Gram-negative bloodstream infections.
ASTar delivered MIC-based rapid phenotypic AST directly from positive blood cultures with 98–99% agreement versus standard testing and a median turnaround of 13.1 h vs 51.2 h. These features support earlier optimization of antimicrobial therapy in Gram-negative BSIs.
Impact: Demonstrates high analytical concordance and markedly faster time-to-result for a rapid phenotypic AST system, a key enabler of stewardship and improved sepsis care.
Clinical Implications: Earlier MIC-based susceptibility reporting can shorten broad-spectrum empiric therapy, enable timely de-escalation/escalation, and potentially improve outcomes in Gram-negative sepsis.
Key Findings
- Across 76 clinical and 32 AR bank Gram-negative isolates, essential and categorical agreement versus SoC were 98.4%/99.3% (clinical) and 95.4%/97.0% (AR bank).
- Median turnaround time was 13.1 hours for ASTar compared with 51.2 hours for standard testing, a reduction of ~38 hours.
- Direct-from-positive blood culture MIC reporting supports faster pathogen-specific therapy decisions.
Methodological Strengths
- Direct-from-blood-culture phenotypic MIC testing with head-to-head comparison against current Standard-of-Care using FDA 2021 breakpoints.
- Inclusion of diverse, well-characterized resistant isolates from the CDC & FDA AR Isolate Bank to challenge performance.
Limitations
- Clinical outcome impact (e.g., mortality, LOS, antibiotic days) was not measured.
- Sample size was modest and focused on Gram-negative BSIs; generalizability to other settings requires further evaluation.
Future Directions: Prospective interventional studies to quantify clinical impact (time-to-targeted therapy, mortality, resistance selection) and workflow integration across diverse centers.
UNLABELLED: Bloodstream infections (BSIs) caused by Gram-negative bacteria are a leading cause of sepsis and mortality, underscoring the need for rapid, reliable antimicrobial susceptibility testing (AST) to guide targeted therapy. We evaluated the analytical performance, turnaround time, and potential clinical impact of the ASTar System (Q-linea), an automated rapid phenotypic AST platform that reports minimum inhibitory concentration-based results directly from positive blood cultures. A total of 76 prospective clinical and 32 antibiotic-resistant specimens from the CDC & FDA AR Isolate Bank selected to represent diverse and well-characterized resistance profiles were tested and compared with the Standard-of-Care (SoC) MicroScan-WalkAway method using 2021 FDA STIC breakpoints. ASTar demonstrated essential and categorical agreement of 98.4% and 99.3% with SoC for clinical isolates, and 95.4% and 97.0% for CDC & FDA AR Isolate Bank specimens, respectively. The median turnaround time for ASTar results was 13.1 h compared with 51.2 h for SoC ( IMPORTANCE: Delays in antimicrobial susceptibility testing for Gram-negative bloodstream infections prolong empiric broad-spectrum therapy and can worsen clinical outcomes. This study presents data on the analytical performance, turnaround time, and potential clinical impact of the ASTar System for rapid antimicrobial susceptibility testing of Gram-negative bloodstream infections. The comparison of ASTar results with a Standard-of-Care method offers data to support clinical laboratories in assessing rapid phenotypic AST platforms, such as ASTar, their role in antimicrobial stewardship, and possible workflow adjustments for faster, targeted therapy in the management of Gram-negative bloodstream infections.