Prognostic and predictive enrichment in sepsis

Ferroptosis targeting offers a therapeutic target for septic cardiomyopathy

Sepsis-induced cardiac dysfunction, usually termed sepsis-induced cardiomyopathy or septic cardiomyopathy(SCM), is developed in approximately 70 % of the patients with sepsis, making it is a major concern for sepsis patients. However, the pathogenesis of SCM remain incompletely understood. Ferroptosis, a newly identified mechanism of regulated cell death, characterized by a decline in antioxidant capacity, iron accumulation, and lipid peroxidation(LPO), is involved in sepsis and SCM. Moreover, ferroptosis inhibitors confer a novel therapeutic regimen in SCM. In this Review, we first summarizes the core mechanism of ferroptosis, with an emphasis on how best to interpret ferroptosis leads to the genesis of SCM. We then highlights our focus on the emerging different types of therapeutic ferroptosis inhibitors and summarizes their pharmacological beneficial effect to treat SCM. This review highlights a novel potential therapeutic strategy for SCM by pharmacologically inhibiting ferroptosis.

Microcirculation properties of 20 % albumin in sepsis; a randomised controlled trial

INTRODUCTION

Sepsis and septic shock are associated with microcirculatory dysfunction, significantly impacting patient outcomes. This study aimed to evaluate the effects of a 20 % albumin bolus on microcirculation compared to crystalloid resuscitation in fluid-responsive patients (ClinicalTrials.govID:NCT05357339).

METHODS

We conducted a single-centre randomised controlled trial, enrolling 103 patients (Albumin n = 52, Control n = 51). Fluid responsiveness was assessed, and fluid was administered in boluses of 100 ml to clinical effect. Microcirculation was measured using the Side stream Dark Field camera and AVA 4.3 software. Baseline characteristics, macrohaemodynamics, and microcirculation parameters were recorded. Three patients were excluded from analysis.

RESULTS

The final cohort comprised 100 patients, 35 (35 %) females with a mean age of 58 years (range: 18-86). The mean APACHE score was 28 (range: 7-45), and the mean SOFA score was 9.4 (range: 1-17). No significant differences in APACHE (26.24 vs. 29.4, p = 0.069) or SOFA (9.08 vs. 9.78, p = 0.32) scores were found for albumin and control group respectively. The albumin group had worse microcirculation at baseline but demonstrated significant improvements in microvascular density and activity at 15 min and 60 min (p < 0.005), while the control group exhibited no significant changes. Additionally, both groups were fluid responsive, with a mean pulse pressure variability of 17 % at admission. There were no significant differences in overall fluid balances, vasopressor days, length of ICU stay, or mortality between groups.

CONCLUSION

This study demonstrates that a 20 % albumin bolus significantly enhances microcirculation in fluid-responsive patients with septic shock. These findings underscore the potential benefits of targeted microcirculation therapy in critically ill patients.

Sepsis and high-density lipoproteins: Pathophysiology and potential new therapeutic targets

In 2020, sepsis has been defined a worldwide health major issue (World Health Organization). Lung, urinary tract and abdominal cavity are the preferred sites of sepsis-linked infection. Research has highlighted that the advancement of sepsis is not only related to the presence of inflammation or microbial or host pattern recognition. Clinicians and researchers now recognized that a severe immunosuppression is also a common feature found in patients with sepsis, increasing the susceptibility to secondary infections. Lipopolysaccharides (LPS) are expressed on the cell surface of Gram-negative, whereas Gram-positive bacteria express peptidoglycan (PGN) and lipoteichoic acid (LTA). The main mechanism by which LPS trigger host innate immune responses is binding to TLR4-MD2 (toll-like receptor4-myeloid differentiation factor 2), whereas, PGN and LTA are exogenous ligands of TLR2. Nucleotide-binding oligomerization domain (NOD)-like receptors are the most well-characterized cytosolic pattern recognition receptors, which bind microbial molecules, endogenous by-products and environmental triggers. It has been demonstrated that high-density lipoproteins (HDL), besides their major role in promoting cholesterol efflux, possess diverse pleiotropic properties, ranging from a modulation of the immune system to anti-inflammatory, anti-apoptotic, and anti-oxidant functions. In addition, HDL are able at i) binding LPS, preventing the activating of TLR4, and ii) inducing the expression of ATF3 (Activating transcription factor 3), a negative regulator of the TLR signalling pathways, contributing at justifying their capacity to hamper infection-based illnesses. Therefore, reconstituted HDL (rHDL), constituted by apolipoprotein A-I/apolipoprotein A-IMilano complexed with phospholipids, may be considered as a new therapeutic tool for the management of sepsis.

Biomarker guided immunomodulatory precision medicine to improve prognostic, predictive and adaptive enrichment strategies in sepsis trials

INTRODUCTION

The aim of this review is to summarize the advances of the last 5 years in the field of biomarker-guided therapeutic approach in sepsis through prognostic, predictive, and adaptive enrichment strategies.

AREAS COVERED

A thorough search of the literature was done based on the existing biomarkers for which clinical trials of integration in the inclusion criteria are available. The authors reviewed the accessible completed and ongoing studies, which use IL-6, ferritin, IL-7, sTREM-1, IL-15, HLA-DR, DPP-3 and/or bioADM for diagnosis of sepsis or septic shock, prognosis of outcome of interest or/and personalized treatment tailored to each patient's endotype classification.

EXPERT OPINION

Inconclusive sepsis trial outcomes highlight the need for strategic protocol design, patient stratification, and biomarker-guided immunomodulatory therapies. Future advancements should focus on real-time biomarker monitoring, personalized treatment, and point-of-care diagnostics to optimize therapeutic efficacy and patient outcomes.

Comprehensive transcriptome profiling in sepsis induced by pyogenic liver abscess

Sepsis is a critical condition characterized by a dysregulated immune response to infection, leading to widespread inflammation, tissue damage, organ failure, and often death. It is a leading cause of morbidity and mortality, particularly in intensive care units, due to its complex pathophysiology involving immune dysregulation, coagulation abnormalities, and metabolic disturbances. Pyogenic liver abscess (PLA) is a significant cause, especially in developing countries where its incidence is rising. PLA, an infectious liver disease, can lead to sepsis, termed sepsis secondary to PLA (SLA). This study aimed to identify key genes and non-coding RNAs involved in the pathogenesis and treatment of SLA. We performed RNA sequencing on peripheral blood samples from healthy individuals, SLA patients, and SLA patients after seven days of therapy. Integrated bioinformatics analysis identified 4549 differentially expressed (DE) mRNAs, 9808 DE lncRNAs, 467 DE circRNAs, and 292 DE miRNAs between SLA patients and healthy controls. Additionally, 3199 mRNAs, 6018 lncRNAs, 161 circRNAs, and 132 miRNAs were differentially expressed between SLA patients before and after seven days of therapy. DE mRNAs in both comparisons were associated with immune responses; DE lncRNAs were linked to the B cell receptor signaling pathway and osteoclast differentiation; DE circRNAs were connected to Chagas disease and the B cell receptor signaling pathway; and DE miRNAs were implicated in the MAPK and estrogen signaling pathways. We constructed lncRNA/circRNA-miRNA-mRNA networks to explore regulatory relationships, validating 16 ceRNAs through RT-PCR. These findings provide new insights into SLA pathogenesis and treatment, potentially guiding the development of novel therapies.

To explore the influencing factors of clinical failure of anti-tumor necrosis factor-α (TNF-α) therapy in sepsis

Sepsis, a condition of significant clinical concern, is characterized by life-threatening organ dysfunction that arises from an infection and is exacerbated by a dysregulated host response. Targeting immune modulation, particularly against tumor necrosis factor-alpha (TNF-α), has emerged as a promising anti-inflammatory therapeutic strategy. However, approaches such as blood purification to eliminate inflammatory mediators or the use of anti-TNF-α therapies have shown limited efficacy in clinical practice. This literature review aims to elucidate the pathogenesis of sepsis and dissect the factors contributing to unfavorable outcomes in TNF-α-targeted treatments. Our analysis highlights several potential reasons for therapeutic failure. Complete blockade of TNF-α may adversely affect both TNFR1 and TNFR2 signaling, thereby reducing the efficacy of TNF-α inhibitors. Additionally, the complex heterogeneity of sepsis, including the etiology of infection, patient-specific factors (e.g., immune responsiveness, body mass index, and obesity), the development of anti-drug antibodies, and treatment duration, significantly influences therapeutic outcomes. Based on these insights, we emphasize the need for precision medicine in sepsis management. This includes stratifying patients into subgroups, using TNFR2 agonists or TNFR1-specific antagonists, refining drug design, implementing multi-target combination therapies, and considering the patient's physiological state at the time of treatment. Collectively, these strategies could enhance the efficacy of sepsis management. This review underscores the multifaceted nature of sepsis treatment and highlights the imperative for personalized, multimodal therapeutic approaches to improve clinical outcomes.

Integrated multiomics and Mendelian randomization identify CHIT1 as a novel sepsis biomarker and therapeutic target

Sepsis is characterized by severe organ failure due to an impaired response to infection. The underlying pathophysiology of sepsis is characterized by concurrent unbalanced hyperinflammatory and immunoparalysis. This study aimed to identify new key biomarkers that could predict outcomes in sepsis patients and explore theirunderlying molecular mechanisms. Bulk transcriptome data (GSE65682, GSE28750, GSE57065, GSE95233) and scRNA-seq data (GSE167363) of sepsis were obtained from the GEO database. Data for MR analysis were sourced from the eQTLGen Consortium and IEU OpenGWAS project. Prognostic biomarkers and potential drug targets for sepsis were identified through univariate Cox regression and MR analysis. The expression of these biomarkers was further validated using scRNA-seq data to investigate the underlying molecular mechanisms. Significantly higher expression of CHIT1 was found at sepsis non-survivor and associated with 28-day mortality of sepsis. scRNA-seq data of septic samples found that CHIT1 mainly expressed in neutrophils, which was also higher in sepsis non-survivors. The CHIT1 + neutrophils expressed higher inflammation related genes of S100A8, S100A9, S100A11, S100A12, IL1R2, IFNGR2, TLR2 and CXCL8 and reduced expression of HLA related genes of HLA-DMA, HLA-DPA1, HLA-DPB1, HLA-DRA, HLA-DRB1 and HLA-DRB5. Moreover, cell-chat analysis also showed that CHIT1 + neutrophils could interact with other immune cell types, including NK cells, erythroid cells, monocytes/macrophages, and DC by the way of ICAM1-(ITGAM + ITGB2) pathway. We identified CHIT1 as new biomarker and potential drug target for sepsis, which may intensify hyperinflammation and immune suppression of neutrophils. Developing immunotherapeutic strategies aimed at targeting CHIT1 would help to enhance sepsis outcomes.

Association Between Type of Immunosuppression and the Incidence, Microbiology, and Outcomes of Bacterial Ventilator-Associated Lower Respiratory Tract Infections: A Retrospective Multicenter Study

OBJECTIVES

Ventilator-associated lower respiratory tract infections (VALRTIs) are among the most common ICU-acquired infections in patients receiving invasive mechanical ventilation (IMV). Immunocompromised patients may have a lower incidence of VALRTI when compared with nonimmunocompromised patients, but the influence of the type of immunosuppression on the epidemiology of VALRTI has not been investigated. The study objectives were to assess the association of the type of immunosuppression with the incidence, microbiology, and outcomes (ICU mortality, ICU length of stay, and duration of IMV) of VALRTI related to bacterial pathogens.

DESIGN

Multicenter, international retrospective cohort study.

SETTING

One hundred eighteen ICUs (118) in nine countries.

PATIENTS

Eight hundred fifty-four immunocompromised adult patients (median age, 65 yr; 57.6% males) requiring IMV for greater than 48 hours, including 162 with hematologic malignancies.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patients with hematologic malignancies had a lower 28-day cumulative incidence of bacterial VALRTI than patients with other types of immunosuppression (13.6% vs. 20.1%; adjusted cause-specific hazard ratio, 0.61; 95% CI, 0.37-0.97), mostly due to a lower incidence of ventilator-associated pneumonia (9.3% vs. 13.9%). The proportion of VALRTI cases related to multidrug-resistant bacteria was similar between groups. Occurrence of bacterial VALRTI was associated with an increased mortality and a longer ICU length of stay, but this effect was independent of the type of immunosuppression.

CONCLUSIONS

Patients with hematologic malignancies had a lower 28-day cumulative incidence of bacterial VALRTI than patients with other types of immunosuppression, mainly due to a lower incidence of ventilator-associated pneumonia.

ADJUNCTIVE VASOPRESSORS AND SHORT-TERM MORTALITY IN ADULTS WITH SEPTIC SHOCK: A SYSTEMATIC REVIEW AND META-ANALYSIS

ABSTRACT

Background: Adjunctive vasopressors are added to norepinephrine in one-third of adults with septic shock in the United States. However, effectiveness of this approach is unclear, and treatment recommendations are based on indirect evidence. We sought to synthesize the direct evidence for adjunctive vasopressor administration in adults with septic shock. Methods: We searched MEDLINE, Embase, and Cochrane Central Register of Controlled Trials from inception to June 7, 2023. We included randomized clinical trials of adults with septic shock comparing adjunctive treatment with a vasopressin analogue, angiotensin II, methylene blue, hydroxocobalamin, or catecholamine analog to standard care vasopressors. The primary outcome was short-term mortality (at or before 28-30 days or intensive care discharge). Secondary outcomes included kidney replacement therapy, digital/peripheral ischemia, and venous thromboembolism. Random-effects meta-analyses were conducted to derive risk ratios (RRs) and 95% CIs. The certainty of the evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation. Results: Of 6,763 records, 17 trials (3,813 participants) were included. Compared with standard care, adjunctive vasopressor administration may reduce short-term mortality risk (RR, 0.92 [95% CI, 0.85-1.00], low certainty, 17 trials [3618 participants]) and likely reduces kidney replacement therapy receipt (RR, 0.92 [95% CI, 0.84-1.01], moderate certainty, eight trials [2,408 participants]). Adjunctive vasopressor treatment may increase risk of digital/peripheral ischemia (RR, 2.44 [95% CI, 1.17-5.10], low certainty, nine trials [2,981 participants]) and venous thromboembolism (RR, 16.48 [95% CI, 0.96-283.17], low certainty, one trial [321 participants]). There was some evidence that the pooled estimate for short-term mortality was different (interaction P = 0.13) for trials adjudicated as low risk of bias (RR, 0.95 [95% CI, 0.87-1.05]) compared with trials adjudicated as some concerns or high risk of bias (RR, 0.82 [95% CI, 0.69-0.97]). The findings were robust to multiple sensitivity and subgroup analyses. Conclusions: In adults with septic shock, adjunctive vasopressors may lower short-term death risk and likely lower kidney replacement therapy risk, but may increase risk of adverse effects. In the United States, adjunctive vasopressor use prevalence in septic shock is disconnected from the low evidence certainty for a favorable mortality-to-risk profile.

A U shaped association between the HCT-ALB and hospital mortality in patients with sepsis

The difference between hematocrit and serum albumin (HCT-ALB) demonstrates diagnostic significance in infectious diseases, yet the nonlinear relationship between HCT-ALB and hospital mortality in ICU patients with sepsis remains unexplored. This retrospective multicenter cohort study analyzed 7,546 ICU sepsis patients (mean age 66 ± 16 years) to elucidate the HCT-ALB-mortality relationship. Using Cox proportional hazards models with smooth curve fitting, we identified a U-shaped association: Threshold analysis revealed an inflection point at 6.1. Below this threshold, each unit HCT-ALB increase corresponded to reduced mortality risk (adjusted HR 0.986, 95%CI 0.972-0.999; P = 0.036). Conversely, values ≥ 6.1 predicted escalating risk (adjusted HR 1.048 per unit increase, 95%CI 1.037-1.060; P < 0.0001). Significant age interaction was observed (P for interaction < 0.05), with heightened mortality risk in elderly patients (≥ 65 years: HR 1.022, 95%CI 1.014-1.031). These findings establish HCT-ALB as a non-linear predictor of sepsis outcomes, emphasizing its critical threshold dynamics and age-dependent prognostic implications.

Fasting-induced ketogenesis sensitizes bacteria to antibiotic treatment

Fasting metabolism is a commonly observed motivational response to acute infections and is conceptualized as being beneficial for host survival. Here, we show that fasting potentiates antibiotic treatment for murine sepsis caused by Salmonella Typhimurium, Klebsiella pneumoniae, and Enterobacter cloacae, resulting in increased bacterial clearance and improved host immune responses and survival. This effect is mediated by fasting-induced ketogenesis and could be alternatively implemented by combination therapy with antibiotics and ketone bodies. We show that the ketone body acetoacetate is an effector that sensitizes bacteria to antibiotic treatment by increasing antibiotic lethality and outer and inner membrane permeability. Our results demonstrate that acetoacetate depletes bacterial amino acids, particularly positively charged amino acids and putrescine, leading to cell membrane malfunctions and redox-related lethality. This study reveals an unrecognized role of ketogenesis in antibiotic treatment and a potential ketone body-based treatment strategy for bacterial sepsis.

[Acute respiratory distress syndrome-quo vadis : Innovative and individualized treatment approaches]

Acute respiratory distress syndrome (ARDS) is a heterogeneous clinical syndrome characterized by variable pathophysiology and different therapeutic approaches. Recent guidelines emphasize the importance of prone positioning and venovenous extracorporeal membrane oxygenation (VV-ECMO) for the most severe cases, while routine recruitment maneuvers and extracorporeal CO2-removal techniques are no longer recommended. To further advance the personalization of ARDS therapy, the identification of ARDS phenotypes using latent class analysis offers promising approaches for individualized treatment. Additionally, adaptive platform trials and artificial intelligence (AI)-driven decision-support systems may optimize future ARDS management. The future of ARDS treatment is becoming increasingly individualized, based on improved patient stratification, innovative study designs, and the targeted use of modern technologies. This article summarizes recent developments in ARDS therapy, particularly regarding personalized treatment strategies, new study designs, and the application of artificial intelligence.

CXCR4+ PD-L1+ neutrophils are increased in non-survived septic mice

The dysregulated host response to infections can lead to sepsis, a complex disease characterized by a spectrum of clinical phenotypes. Using scRNA-seq, we analyzed the immune cell of survived and non-survived CLP-septic mice to gain insights into the immunological mechanisms by which neutrophils contribute to the hyperinflammatory phenotype. Our findings reveal that non-survived mice exhibit increased frequencies of immature CXCR4+ PD-L1+ neutrophils in the bloodstream, accompanied by an accumulation of trafficking-specific CXCR4+ PD-L1+ neutrophils into the lungs. The IFN-gamma and LPS promote the PD-L1 expression on neutrophils and an activation profile associated with inflammation and organ damage. Notably, abrogating the IFN-gamma reduced susceptibility to CLP-sepsis and diminished CXCR4+ PD-L1+ neutrophils frequency. This study provides insights into the immune cell activation profiles associated with the worsening of the CLP-sepsis, and the CXCR4+ PD-L1+ neutrophils population highlighted here represents a promising target for therapeutic modulation in clinical sepsis hyperinflammatory phenotype.

Evidence-based personalised medicine in critical care: a framework for quantifying and applying individualised treatment effects in patients who are critically ill

Clinicians aim to provide treatments that will result in the best outcome for each patient. Ideally, treatment decisions are based on evidence from randomised clinical trials. Randomised trials conventionally report an aggregated difference in outcomes between patients in each group, known as an average treatment effect. However, the actual effect of treatment on outcomes (treatment response) can vary considerably between individuals, and can differ substantially from the average treatment effect. This variation in response to treatment between patients-heterogeneity of treatment effect-is particularly important in critical care because common critical care syndromes (eg, sepsis and acute respiratory distress syndrome) are clinically and biologically heterogeneous. Statistical approaches have been developed to analyse heterogeneity of treatment effect and predict individualised treatment effects for each patient. In this Review, we outline a framework for deriving and validating individualised treatment effects and identify challenges to applying individualised treatment effect estimates to inform treatment decisions in clinical care.

Combining CD64 and CD123 Biomarkers for Sepsis Early Diagnosis and Severity Assessment via PD-L1 Antibody Affinity Microfluidic (PAAM) Chip in Trace Clinical Samples

Sepsis, a lethal organ dysfunction caused by a dysregulated host response to infection, is the leading cause of worldwide in-hospital mortality. However, the early diagnostic methods for sepsis are still urgent for guiding accurate antibiotic usage and improving the survival rate of the patients. Herein, we constructed a PD-L1 antibody affinity microfluidic (PAAM) chip for early sepsis diagnosis and severity assessment. The chip was used to capture PD-L1-expressing leukocytes from whole blood samples obtained from healthy control (HC) volunteers (n = 15) and sepsis patients on day 1 (D1) and day 7 (D7) (n = 20), and there was a statistically significant difference between HC and sepsis patients (p < 0.0001), and the AUC was 0.96. However, there was no significant difference in the number of cells captured on-chip between sepsis patients on D1 and D7 (p = 0.16). Therefore, we performed immunofluorescence staining of PD-L1, CD64, and CD123 on the chip. The results showed that the combination of PD-L1, CD64, and CD123 for sepsis diagnosis had an AUC of 0.98, and there was a significant difference in PD-L1+/CD64+/CD123+ leukocytes between sepsis patients on D1 and on D7 (p < 0.0001). In conclusion, we found that the combination of multiple biomarkers was more precise and dependable for sepsis diagnosis and severity assessment.

Ferroptosis-related protein biomarkers for diagnosis, differential diagnosis, and short-term mortality in patients with sepsis in the intensive care unit

Background

Sepsis is a disease with high mortality caused by a dysregulated response to infection. Ferroptosis is a newly discovered type of cell death. Ferroptosis-related genes are involved in the occurrence and development of sepsis. However, research on the diagnostic value of ferroptosis-related protein biomarkers in sepsis serum is limited. This study aims to explore the clinical value of Ferroptosis-related proteins in diagnosing sepsis and predicting mortality risk.

Methods

A single-center, prospective, observational study was conducted from January to December 2023, involving 170 sepsis patients, 49 non-septic ICU patients, and 50 healthy individuals. Upon ICU admission, biochemical parameters, GCS, SOFA, and APACHE II scores were recorded, and surplus serum was stored at -80°C for biomarker analysis via ELISA. Diagnostic efficacy was evaluated using ROC curve analysis.

Results

Baseline serum levels of ACSL4, GPX4, PTGS2, CL-11, IL-6, IL-8, PCT, and hs-CRP significantly differed among sepsis, non-septic, and healthy individuals (all p-value < 0.01). ACSL4, GPX4, PTGS2, IL-6, IL-8, PCT, and hs-CRP demonstrated high diagnostic and differential diagnostic performance (AUC: 0.6688 to 0.9945). IL-10 and TNF-α showed good diagnostic performance (AUC = 0.8955 and 0.7657, respectively). ACSL4 (AUC = 0.7127) was associated with predicting sepsis mortality. Serum levels of ACSL4, CL-11, and IL-6 above the cut-off value were associated with shorter survival times. ACSL4 levels were positively correlated with SOFA (Rho = 0.354, p-value < 0.0001), APACHE II (Rho = 0.317, p-value < 0.0001), and septic shock (Rho = 0.274, p-value = 0.003) scores but negatively correlated with the GCS score (Rho = -0.218, p-value = 0.018). GPX4 levels were positively correlated with SOFA (Rho = 0.204, p-value = 0.027) and APACHE II (Rho = 0.233, p-value = 0.011) scores.

Conclusion

ACSL4 and GPX4 have strong diagnostic and differential diagnostic value in sepsis, including the ability to predict 28-day mortality in sepsis patients, and may become new potential serum markers for the diagnostic and differential diagnostic of sepsis.

The type of pathogen is associated with organ failure and legacy dysfunction in patients with sepsis

Introduction

Is there a difference in pathogen infection among sepsis patients with different organ dysfunction and Post-sepsis persistent organ dysfunction? Is this related to survival? It is currently unclear.

Methods

This study reviewed 1982 sepsis patients between December 2019 and September 2023, and included 619 patients after removing patients with missing data. Of these, 332 were tested for metagenomic next-generation sequencing (mNGS). First, the pathogens distribution was assessed in all NGS-positive patients, followed by patients with different organ dysfunction (excluding those who died during hospitalization). Lastly, the survival analysis was conducted on patients infected with different pathogens.

Results

The results showed that the mortality rate in our cohort was 27.63% in patients with sepsis, and patients with Respiratory, Liver, Circulatory, Hematologic, Neurological, and Renal dysfunction had poor survival. And patients with post-sepsis persistent organ dysfunction after sepsis have worse survival rates. In addition, we found the infection rates of Legionella and Betapapillomavirus were higher in patients with liver dysfunction. The infection rates of Mastadenovirus, Enterococcus, and Candida were higher in patients with neurological dysfunction. The infection rates of Candida were higher in patients with renal dysfunction and hematologic dysfunction. The infection rates of Moraxella were higher in patients with circulatory dysfunction. The infection rates of Enterococcus, Pneumocystis, and Acinetobacter were higher in patients with Post-sepsis cardiac dysfunction.The infection rates of Enterococcus, Acinetobacter, and Morganella were higher in patients with Post-sepsis liver dysfunction. The infection rates of Enterococcus, Acinetobacter, and Staphylococcus were higher in patients with Post-sepsis respiratory dysfunction. The infection rates of Enterococcus, Candida, Pneumocystis, Staphylococcus, and Listeria were higher in patients with Post-sepsis renal dysfunction. In addition, we found that patients with Escherichia infection in sepsis had the lowest survival rate. The survival rate of patients with Enterococcus infection combined with post-sepsis persistent respiratory dysfunction is also worse.

Discussion

In conclusion, there are differences in the types and proportions of pathogens infected in patients with different organ dysfunction and Post-sepsis persistent organ dysfunction. The combination of Escherichia infection and Enterococcus infection with post-sepsis persistent respiratory dysfunction can affect the survival of patients. We should strengthen the management of sepsis patients, especially those with Post-sepsis persistent organ dysfunction.

Haemoadsorption to remove inflammatory mediators in sepsis: past, present, and future

While a dysregulated immune response is at the center of the sepsis definition, standard care is still solely focussed on prompt administration of antimicrobial therapy, source control, resuscitation and organ supportive therapies. Extracorporeal blood purification therapies, such as haemoadsorption, have been proposed as a possible adjunctive therapy to standard care in sepsis. These adsorption devices aim to rebalance the dysregulated immune response by removal of excessive amounts of circulating inflammatory mediators, including cytokines and endotoxins. Thus far, the effects of haemoadsorption on clinical outcomes have been insufficiently studied and although its routine use is not justified based on the current evidence, multiple centers use these devices in patients with severe septic shock. This narrative review describes the most well-studied adsorption devices as well as a novel selective adsorption device called the 'IL-6-Sieve', including in vitro data showing its capturing potential. Finally, it addresses important considerations for future trials on haemoadsorption in septic patients.

Framework for Kidney Health Follow-Up Among Neonates With Critical Cardiac Disease: A Report From the Neonatal Kidney Health Consensus Workshop

Acute kidney injury is common among neonates with critical cardiac disease. Risk factors and associations with kidney-related outcomes are heterogeneous and distinct from other neonates. As survival of children with critical cardiac disease increases to adulthood, the burden of chronic kidney disease is increasing. Thirty percent to 50% of adults with congenital heart disease have impaired kidney function, even in the absence of prior kidney injury episodes. This may be related to the current standardized acute kidney injury criteria, which may not fully capture clinically meaningful kidney injury and long-term kidney health risks. An improved understanding of which neonates with critical cardiac disease should undergo kidney health follow-up is imperative. During the National Institutes of Health-supported Neonatal Kidney Health Consensus Workshop to Address Kidney Health meeting conducted in February 2024, a panel of 51 neonatal nephrology experts focused on at-risk groups: (1) preterm infants, (2) critically ill infants with acute kidney injury, and (3) infants with critical cardiac disease. The critical cardiac disease subgroup, comprising multidisciplinary experts, used a modified Delphi process to achieve consensus on recommendations for kidney health follow-up. In this report, we review available data on kidney health follow-up in critical cardiac disease and summarize the 2 consensus-based recommendations. We introduce novel diagnostic and risk-stratification tools for acute kidney injury diagnosis in neonates with cardiac disease to guide follow-up recommendations. Finally, we identify important knowledge gaps, representing areas of focus for future research. These should be prioritized to understand and improve long-term kidney health in critical cardiac disease.

Role of plasma and blood-cell co-metagenomic sequencing in precise diagnosis and severity evaluation of sepsis, a prospective cohort study in sepsis patients

PURPOSES

Sepsis caused great clinical burden all over the world. This study clarified the value of plasma metagenomic next-generation sequencing (p-mNGS) and blood cell mNGS (bc-mNGS) in sepsis diagnosis and evaluation.

METHODS

One hundred and fourty-seven blood samples were collected from sepsis patients who met sepsis 3.0 criteria. Blood culture (BC), qPCR, p-mNGS, bc-mNGS and necessary routine assays were conducted. Taking BC and qPCR as reference, diagnosis performance of p-mNGS and bc-mNGS was analyzed. Blood transcriptome was conducted to evaluate the immunological response of patients in groups with different p/bc-mNGS results. Impact of antibiotic use on different methods was also analyzed.

RESULTS

The p-mNGS demonstrated a sensitivity of 100% for bacteria/fungi and 97% for viruses, which was higher than bc-mNGS (88% for bacteria and fungi, 71% for viruses). However, bc-mNGS showed higher concordance with BC results, which indicated that co-mNGS (p-mNGS plus bc-mNGS) protocol increased sensitivity and was helpful to justify viable blood pathogens in sepsis patients. This study showed that p-mNGS(+) & bc-mNGS(+) samples represented more activated immunity response (low expression of interferon-induced genes and high expression of JAK-STAT pathway genes), poorer clinical laboratory indicators (higher Sequential Organ Failure Assessment, higher procalcitonin and higher C-reactive protein) and lower survival rate. This study also proved that the use of broad-spectrum antibiotics affected much less on p/bc-mNGS diagnostic ability than on BC.

CONCLUSIONS

This research highlighted the potential value of plasma and blood-cell co-metagenomic sequencing in precise diagnosis and severity evaluation of sepsis patients, which will benefit the management of sepsis patients.

Transcriptomics in Human Septic Shock: State of the Art

Background: Septic shock is a complex syndrome characterized by signs of intense systemic inflammation and a profound dysregulation of the immune response. Large-scale gene expression analysis is a valuable tool in this scenario because sepsis affects various cellular components and signaling pathways. Results: In this article, we provide an overview of the transcriptomic studies that investigated human sepsis from 2007 to 2024, highlighting their major contributions. Conclusions: The field, however, still faces substantial limitations and several challenges. To advance further, we believe that standardization of sample collection and data analysis, preservation of cell and tissue architecture, and integration with other omics techniques are crucial for a broader understanding of this lethal disease.

Advancements in omics technologies: Molecular mechanisms of acute lung injury and acute respiratory distress syndrome (Review)

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is an inflammatory response arising from lung and systemic injury with diverse causes and associated with high rates of morbidity and mortality. To date, no fully effective pharmacological therapies have been established and the relevant underlying mechanisms warrant elucidation, which may be facilitated by multi‑omics technology. The present review summarizes the application of multi‑omics technology in identifying novel diagnostic markers and therapeutic strategies of ALI/ARDS as well as its pathogenesis.

Early sepsis recognition: a pilot study using a rapid high-multiplex host-response mRNA diagnostic test

BACKGROUND

Early sepsis diagnosis is essential to allow timely initiation of adequate care. The TriVerity™ Test, performed on the Myrna™ Instrument, is the first rapid high-multiplex host-response mRNA diagnostic test that supports clinical decision-making by evaluating the likelihood of bacterial and/or viral infections and severity of illness. We present findings of the first, proof of concept, real-world evaluation in an emergency department (ED).

METHODS

Blood was collected in PAXgene® Blood RNA tubes from adult patients visiting the ED with suspicion of infection between 4th December 2023 and 22nd January 2024. TriVerity was performed within 1 h (RNA extraction and amplification of 29 host mRNAs using LAMP technology on the Myrna Instrument within approximately 30 min). TriVerity generates three diagnostic scores (likelihood of bacterial infection, viral infection, and illness severity), each classified into five discrete interpretation bands (very low, low, moderate, high, and very high). Post hoc chart reviews were performed after hospital discharge to clinically adjudicate the infection status (consensus and forced adjudication).

RESULTS

Among 60 patients, there were 20 (33%) bacterial infections, 15 (25%) viral infections, 11 (18%) bacterial-viral coinfections and 14 (23%) did not have an infection under forced adjudication. Under consensus adjudication, bacterial results demonstrated 95% rule-in specificity and 95% rule-out sensitivity. Viral results demonstrated rule-in specificity 100% and 92% rule-out sensitivity. Since only three patients were admitted to the ICU or died in this cohort, we cannot draw firm conclusions about the predictive value of the test for severe endpoints.

CONCLUSIONS

TriVerity is a rapid whole-blood host-response test to reliably detect the presence or absence of bacterial and/or viral infections, as well as to assess illness severity in patients presenting to the ED. Its quick turnaround time aligns with the ED workflow, offering timely insights for clinical decision-making. Results from upcoming large-scale validation studies will provide more detailed results on the diagnostic and prognostic accuracy of the test.

Mechanisms of sepsis-induced acute liver injury: a comprehensive review

Sepsis is a severe, often life-threatening form of organ dysfunction that arises from an inappropriately regulated host response to infectious pathogen exposure. As the largest gland in the body, the liver serves as a regulatory hub for metabolic, immune, and detoxification activity. It is also an early sepsis target organ such that hepatic dysfunction is observed in 34-46% of patients with sepsis. The precise mechanisms that give rise to sepsis-induced liver injury, however, remain incompletely understood. Based on the research conducted to date, dysregulated systemic inflammation, microbial translocation, microcirculatory abnormalities, cell death, metabolic dysfunction, and liver inflammation may all contribute to the liver damage that can arise in the context of septicemia. This review was developed to provide an overview summarizing the potential mechanisms underlying sepsis-induced liver injury, informing the selection of potential targets for therapeutic intervention and providing a framework for the alleviation of patient symptoms and the improvement of prognostic outcomes.

The effect of therapeutic plasma exchange on the inflammatory response in septic shock: a secondary analysis of the EXCHANGE-1 trial

BACKGROUND

Sepsis and septic shock, defined by a profound immune dysregulation, are among the leading causes of death in the intensive care unit (ICU). Despite advances in understanding the underlying pathophysiology, evidence for specific immunomodulatory treatment does not exist to date. Therapeutic plasma exchange (TPE) represents an adjunctive treatment approach to rebalance immune homeostasis. In the EXCHANGE-1 trial, we recently demonstrated a rapid hemodynamic improvement, possibly caused by the removal of harmful mediators and the replacement of protective plasma proteins. The aim of this secondary analysis is to further characterize the underlying immunomodulatory effects and to identify biomarkers that may predict treatment response.

METHODS

This secondary analysis included patients in early septic shock (< 24 h duration) and a norepinephrine (NE) dose of ≥ 0.4 μg/kg/min. Patients were randomized 1:1 to receive standard of care (SOC) or SOC + one single TPE and plasma samples were collected before and after TPE. Within-group and between group effects of circulating levels of acute-phase proteins [CRP and Pentraxin3 (PTX3)], inflammatory mediators (IL-4, IL-6, IL-8, IL-10, TNF-α, IL-2Rα/CD25) and damage-associated molecular pattern (DAMP) [cell-free DNA (cfDNA)] were analyzed via paired t test or Wilcoxon signed-rank test and a mixed-effects model. Multivariate mixed-effects modeling of NE and lactate reduction was performed to investigate if cfDNA could be associated with treatment response to TPE.

RESULTS

TPE led to a significant reduction in circulating acute-phase protein levels (CRP p = 0.00976, PTX3 p = 0.0001). Pro-inflammatory cytokines, such as circulating TNF-α-, IL-6- und IL-8-levels, were significantly reduced in both groups with no significant difference between treatment groups except for IL-2Rα/CD25 (p ≤ 0.0001). In a multivariate mixed-effects model, rising cfDNA levels over the first 6 h indicated refractoriness to SOC treatment regarding NE (p = 0.004) and lactate (p = 0.001), whereas those receiving TPE demonstrated sustained reductions in both parameters.

CONCLUSIONS

In this secondary analysis of the EXCHANGE-1 trial adjunctive TPE is associated with the reduction of acute-phase proteins and IL-2Rα/CD25, however not with the reduction of pro-inflammatory cytokines. This phenomenon could contribute to the observed enhancement in hemodynamics among patients with septic shock. Furthermore, TPE may be particularly beneficial for patients with septic shock who exhibit rising levels of cfDNA.

NLRP3 Inflammasome Targeting Offers a Novel Therapeutic Paradigm for Sepsis-Induced Myocardial Injury

Cardiac or myocardial dysfunction induced by sepsis, known as sepsis-induced cardiomyopathy or sepsis-induced myocardial injury (SIMI), is a common complication of sepsis and is associated with poor outcomes. However, the pathogenesis and molecular mechanisms underlying SIMI remain poorly understood, requiring further investigations. Emerging evidence has shown that NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasomes contribute to SIMI. Compounds that inhibit NLRP3-associated pyroptosis may exert therapeutic effects against SIMI. In this review, we first outlined the principal elements of the NLRP3 signaling cascade and summarized the recent studies highlighting how NLRP3 activation contributes to the pathogenesis of SIMI. We outlined selective small-molecule modulators that function as NLRP3 inhibitors and delineated their mechanisms of action to attenuate SIMI. Finally, we discuss the major limitations of the current therapeutic paradigm and propose possible strategies to overcome them. This review highlights the pharmacological inhibition of SIMI as a promising therapeutic strategy.

Sepsis subphenotypes: bridging the gaps in sepsis treatment strategies

Sepsis, a heterogeneous illness produced by a dysregulated host response to infection, remains a severe mortality risk. Recent discoveries in sepsis research have stressed phenotyping as a feasible strategy for tackling heterogeneity and enhancing therapy precision. Sepsis phenotyping has moved from traditional stratifications based on severity and prognosis to dynamic, phenotype-driven therapeutic options. This review covers recent progress in connecting sepsis subgroups to personalized treatments, with a focus on phenotype-based therapeutic predictions and decision-support systems. Despite ongoing challenges, such as standardizing phenotyping frameworks and incorporating findings into clinical practice, this topic has enormous promise. By investigating phenotypic variation in therapy responses, we hope to uncover new biomarkers and phenotype-driven therapeutic solutions, laying the groundwork for more effective therapies and, ultimately improving patient outcomes.

Long-term characteristics and outcomes of septic critically ill patients with and without COVID-19

BACKGROUND

In-hospital mortality of septic critically ill patients with COVID-19 is significantly higher than in those without COVID-19. The knowledge on long-term outcomes remains scarce. In this retrospective analysis, we compare clinical characteristics, long-term functional outcomes, and survival in septic critically ill patients with and without COVID-19.

METHODS

Data of septic critically ill patients without COVID-19 were collected as part of the Comprehensive Sepsis Center Dresden-Kreischa registry from 2020 to 2023. The data of septic critically ill patients with COVID-19 were collected as part of the local ARDS/COVID-19 registry over the same period. Diagnosis of sepsis was based on the Sepsis-3 definition. Variables collected for analyses were obtained from electronic health records. Long-term follow-up was performed 6-12 months after sepsis diagnosis. Survival was depicted using Kaplan-Meier curves. Associations between long-term mortality and risk factors were modeled by Cox Regression.

RESULTS

372 septic patients without COVID-19 and 301 with COVID-19 were enrolled. Septic patients with COVID-19 were significantly younger, had a significantly lower Charlson Comorbidity Index, and had a significantly higher SOFA score at ICU admission. Long-term follow-up showed a significantly higher mortality in septic patients with COVID-19 (73.4 % vs. 30.1 %; HR 3.4 (95 % CI 2.73-4.27; p < 0.05)). COVID-19 infection was associated with significant increased mortality (adjusted HR 3.27; 95 % CI 2.48-4.33; p < 0.05) and reduced health-related quality of life, measured by the EQ-5D-3 L Index, (0.56 (0.16-0.79) vs. 0.79 (0.69-0.99); p < 0.05).

CONCLUSIONS

In our cohort of septic critically ill patients, health-related quality of life and long-term survival were considerably reduced in patients with concomitant COVID-19. Furthermore, COVID-19 could be identified as an independent risk factor for higher long-term mortality in these patients.

The efficacy and safety of thymosin α1 for sepsis (TESTS): multicentre, double blinded, randomised, placebo controlled, phase 3 trial

OBJECTIVE

To evaluate whether the immunomodulatory drug thymosin α1 reduces mortality in adults with sepsis.

DESIGN

Multicentre, double blinded, placebo controlled phase 3 trial.

SETTING

22 centres in China, September 2016 to December 2020.

PARTICIPANTS

1106 adults aged 18-85 years with a diagnosis of sepsis according to sepsis-3 criteria and randomly assigned in a 1:1 ratio to receive thymosin α1 (n=552) or placebo (n=554). A stratified block method was used for randomisation, and participants were stratified by age (<60 and ≥60 years) and centre.

INTERVENTIONS

Subcutaneous injection of thymosin α1 or placebo every 12 hours for seven days unless discontinued owing to discharge from the intensive care unit, death, or withdrawal of consent.

MAIN OUTCOME MEASURE

The primary outcome was 28 day all cause mortality after randomisation. All analyses were based on a modified intention-to-treat set, including participants who received at least one dose of study drug.

RESULTS

Of 1106 adults with sepsis enrolled in the study, 1089 were included in the modified intention-to-treat analyses (thymosin α1 group n=542, placebo group n=547). 28 day all cause mortality occurred in 127 participants (23.4%) in the thymosin α1 group and 132 (24.1%) in the placebo group (hazard ratio 0.99, 95% confidence interval 0.77 to 1.27; P=0.93 with log-rank test). No secondary or safety outcome differed statistically significantly between the two groups. The prespecified subgroup analysis showed a potential differential effect of thymosin α1 on the primary outcome based on age (<60 years: hazard ratio 1.67, 1.04 to 2.67; ≥60 years: 0.81, 0.61 to 1.09; P for interaction=0.01) and diabetes (diabetes: 0.58, 0.35 to 0.99; no diabetes: 1.16, 0.87 to 1.53; P for interaction=0.04).

CONCLUSIONS

This trial found no clear evidence to suggest that thymosin α1 decreases 28 day all cause mortality in adults with sepsis.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02867267.

Exploring the Relationship Between Sleep Apnea, Myocardial Infarct Size, and Coronary Collaterals in Acute Myocardial Infarction: A Multidisciplinary Study

Purpose

We designed a study investigating the cardioprotective role of sleep apnea (SA) in patients with acute myocardial infarction (AMI), focusing on its association with infarct size and coronary collateral circulation.

Methods

We recruited adults with AMI, who underwent Level-III SA testing during hospitalization. Delayed-enhancement cardiac magnetic resonance (CMR) imaging was performed to quantify AMI size (percent-infarcted myocardium). Rentrop Score quantified coronary collateralization (scores 0-3, higher scores indicating augmented collaterals). Group differences in Rentrop grade and infarct size were compared using the Wilcoxon Rank-Sum test and Fisher's Exact test as appropriate, with a significance threshold set at p <0.05.

Results

Among 33 adults, mean age was 54.4±11.5 and mean BMI was 28.4±5.9. 8 patients (24%) had no SA, and 25 (76%) had SA (mild n=10, moderate n=8, severe n=7). 66% (n=22) underwent CMR, and all patients had Rentrop scores. Median infarct size in the no-SA group was 22% versus 28% in the SA group (p=0.79). While we did not find statistically significant differences, moderate SA had a trend toward a smaller infarct size (median 15.5%; IQR 9.23) compared to the other groups (no SA [22.0%; 16.8,31.8], mild SA [27%; 23.8,32.5], and severe SA [34%; 31.53], p=0.12). A higher proportion of moderate SA patients had a Rentrop grade >0, with a trend toward significance (moderate SA versus other groups: 62.5% versus 28%, p=0.08).

Conclusion

Our study did not find statistically significant differences in cardiac infarct size and the presence of coronary collaterals by sleep apnea severity among patients with AMI. However, our results are hypothesis-generating, and suggest that moderate SA may potentially offer cardioprotective benefits through enhanced coronary collaterals. These insights call for future research to explore the heterogeneity in ischemic preconditioning by SA severity and hypoxic burden to guide tailored clinical strategies for SA management in patients with AMI.

Drp1-associated genes implicated in sepsis survival

Sepsis is a severe and life-threatening medical syndrome that can lead to organ failure and death. Despite advances in medical treatment, current therapies are often inadequate, with high septic mortality rates. Therefore, there is a critical need for reliable prognostic markers to be used in clinical settings to improve the management and outcomes of patients with sepsis. Recent studies have suggested that mitochondrial dynamics, including the processes of mitochondrial fission and fusion, are closely related to the severity of sepsis and the status of inflammation. By monitoring transcriptomic signals related to mitochondrial dynamics, new and reliable biomarkers can be engineered to more accurately predict sepsis survival risk. Such biomarkers would be invaluable in clinical settings, aiding healthcare providers in the early identification of high-risk patients and improving treatment strategies. To achieve this goal, we utilized the major mitochondrial fission regulatory protein dynamin-related protein 1 (Drp1, gene code DNM1L) and identified Drp1-associated genes that are enriched with sepsis survival genes. A 12-gene signature (GS) was established as a differentially expressed gene (DEG)-based GS. Next, we compared genes of proteins that interact with Drp1 to sepsis survival genes and identified 7 common genes, establishing a GS we term as protein-protein interaction (PPI)-based GS. To evaluate if these GSs can predict sepsis survival, we used publicly available human blood transcriptomic datasets from sepsis patients. We confirmed that both GSs can successfully predict sepsis survival in both discovery and validation cohorts with high sensitivity and specificity, with the PPI-based GS showing enhanced prognostic performance. Together, this study successfully engineers a new and validated blood-borne biomarker (PPI-based 7-gene GS) for sepsis survival risk prediction. This biomarker holds the potential for improving the early identification of high-risk sepsis patients and optimizing personalized treatment strategies to reduce sepsis mortality.

Aiming for precision: personalized medicine through sepsis subtyping

According to the latest definition, sepsis is characterized by life-threatening organ dysfunction caused by a dysregulated host response to an infection. However, this definition fails to grasp the heterogeneous nature and the underlying dynamic pathophysiology of the syndrome. In response to this heterogeneity, efforts have been made to stratify sepsis patients into subtypes, either based on their clinical presentation or pathophysiological characteristics. Subtyping introduces the possibility of the implementation of personalized medicine, whereby each patient receives treatment tailored to their individual disease manifestation. This review explores the currently known subtypes, categorized by subphenotypes and endotypes, as well as the treatments that have been researched thus far in the context of sepsis subtypes and personalized medicine.

Methods for phenotyping adult patients with acute kidney injury: a systematic review

BACKGROUND

Acute kidney injury (AKI) is a multifaceted disease characterized by diverse clinical presentations and mechanisms. Advances in artificial intelligence have propelled the identification of AKI subphenotypes, enhancing our capacity to customize treatments and predict disease trajectories.

METHODS

We conducted a systematic review of the literature from 2017 to 2022, focusing on studies that utilized machine learning techniques to identify AKI subphenotypes in adult patients. Data were extracted regarding patient demographics, clustering methodologies, discriminators, and validation efforts from selected studies.

RESULTS

The review highlights significant variability in subphenotype identification across different populations. All studies utilized clinical data such as comorbidities and laboratory variables to group patients. Two studies incorporated biomarkers of endothelial activation and inflammation into the clinical data to identify subphenotypes. The primary discriminators were comorbidities and laboratory trajectories. The association of AKI subphenotypes with mortality, renal recovery and treatment response was heterogeneous across studies. The use of diverse clustering techniques contributed to variability, complicating the application of findings across different patient populations.

CONCLUSIONS

Identifying AKI subphenotypes enables clinicians to better understand and manage individual patient trajectories. Future research should focus on validating these phenotypes in larger, more diverse cohorts to enhance their clinical applicability and support personalized medicine in AKI management.

Identifying novel aging-related diagnostic and prognostic models and aging-targeted drugs for sepsis patients

Sepsis is defined as a dysfunctional, life-threatening response to infection leading to multiorgan dysfunction and failure. During the past decade, studies have highlighted the relationship between sepsis and aging. However, the role of aging-related mechanisms in the progression and prognosis of sepsis remains unclear. In the present study, we divided sepsis patients into High- and Low-aging groups based on the gene set variation analysis (GSVA) scores of GOBP-AGING gene set. Sepsis patients in the high-aging group exhibited higher levels of infiltration of innate immune cells, lower levels of infiltration of adaptive immune cells, and a worse prognosis than those in the Low-aging group. Additionally, the MPO to MME ratio (MPO/MME) appears to be an effective biomarker for predicting the prognosis of sepsis patients. Moreover, ARG1/SEC63 and ARG1/CDKN1C appear to be effective and robust biomarkers for the early diagnosis of sepsis patients. Finally, we found that thalidomide (TAL) significantly ameliorated LPS induced inflammation and organ injury and attenuated LPS induced cellular senescence in lung and kidney. Overall, this study provides new insights into the heterogeneity of sepsis, reveals the vital role of aging-related markers in the prognosis and diagnosis of sepsis and demonstrates that TAL is a novel aging-targeted drug for sepsis patients by attenuating LPS induced cellular senescence.

Urinary proteomics identifies distinct immunological profiles of sepsis associated AKI sub-phenotypes

BACKGROUND

Patients with sepsis-induced AKI can be classified into two distinct sub-phenotypes (AKI-SP1, AKI-SP2) that differ in clinical outcomes and response to treatment. The biologic mechanisms underlying these sub-phenotypes remains unknown. Our objective was to understand the underlying biology that differentiates AKI sub-phenotypes and associations with kidney outcomes.

METHODS

We prospectively enrolled 173 ICU patients with sepsis from a suspected respiratory infection (87 without AKI and 86 with AKI on enrollment). Among the AKI patients, 66 were classified as AKI-SP1 and 20 as AKI-SP2 using a three-plasma biomarker classifier. Aptamer-based proteomics assessed 5,212 proteins in urine collected on ICU admission. We compared urinary protein abundances between AKI sub-phenotypes, conducted pathway analyses, tested associations with risk of RRT and blood bacteremia, and predicted AKI-SP2 class membership using LASSO.

MEASUREMENT AND MAIN RESULTS

In total, 117 urine proteins were higher in AKI-SP2, 195 were higher in AKI-SP1 (FDR < 0.05). Urinary proteins involved in inflammation and chemoattractant of neutrophils and monocytes (CXCL1 and REG3A) and oxidative stress (SOD2) were abundant in AKI-SP2, while proteins involved in collagen deposition (GP6), podocyte derived (SPOCK2), proliferation of mesenchymal cells (IL11RA), anti-inflammatory (IL10RB and TREM2) were abundant in AKI-SP1. Pathways related to immune response, complement activation and chemokine signaling were upregulated in AKI-SP2 and pathways of cell adhesion were upregulated in AKI-SP1. Overlap was present between urinary proteins that differentiated AKI sub-phenotypes and proteins that differentiated risk of RRT during hospitalization. Variable correlation was found between top aptamers and ELISA based protein assays. A LASSO derived urinary proteomic model to classify AKI-SP2 had a mean AUC of 0.86 (95% CI: 0.69-0.99).

CONCLUSION

Our findings suggest AKI-SP1 is characterized by a reparative, regenerative phenotype and AKI-SP2 is characterized as an immune and inflammatory phenotype associated with blood bacteremia. We identified shared biology between AKI sub-phenotypes and eventual risk of RRT highlighting potential therapeutic targets. Urine proteomics may be used to non-invasively classify SP2 participants.

MiRNAs and Neutrophil-Related Membrane Proteins from Plasma-Derived Extracellular Vesicles for Early Prediction of Organ Dysfunction and Prognosis in Septic Patients

Purpose

The pathogenesis of sepsis-induced organ dysfunction remains elusive, and the mortality remains alarmingly high. We sought to investigate the profile of extracellular vesicles (EVs)-mediated communication between plasma and polymorphonuclear neutrophils (PMNs) in sepsis, and to elucidate whether miRNAs and PMN-related membrane proteins from plasma-derived EVs (plasma-EVs) are associated with sepsis-induced organ dysfunction and prognosis.

Methods

PMN-derived EVs (PMN-EVs) were isolated from the blood samples of healthy controls (N=3) and patients with septic shock (N=3) after ICU admission. We performed miRNA sequencing of the isolated EVs, followed by bioinformatic analysis. A miRNA model for comparing PMN-EVs and plasma-EVs was successfully established in the training cohort. Furthermore, miRNAs and PMN-related membrane proteins from the plasma-EV model were confirmed in the validation cohort. A logistic regression model, receiver operating characteristic (ROC) curves, and Kaplan-Meier analyses were performed to evaluate the efficiency of diagnostic and/or prognostic performance. Further, in vivo and in vitro experiments were conducted to explore the involvement of plasma-EVs in PMNs autophagy.

Results

Fifty-five miRNAs from PMN-EVs differed significantly between the healthy controls and patients with septic shock. Furthermore, the plasma-EV model (six miRNAs and eight PMN-related membrane proteins) was confirmed in the validation cohort, demonstrating that miR-34a-5p, miR-503-5p, miR-4772-3p, ITGAM, MPO, and MMP9 serve as sepsis biomarkers for distinguishing lung, liver, and kidney dysfunction. Kaplan-Meier survival analysis showed that miR-34a-5p, miR-4772-3p, ITGAM, and MMP9 were potential prognostic predictors. Finally, we found that plasma-EVs from sepsis patients exert an inhibitory effect on PMNs autophagy, which can be reversed by EV inhibitors such as GW4869 and enoxaparin.

Conclusion

These findings suggest that miRNAs and PMN-related membrane proteins from plasma-EVs could be valuable diagnostic tools for identifying sepsis-induced organ dysfunction and predicting prognosis, enabling proactive management of sepsis by physicians and improving the prognosis of sepsis patients.

Identification of severe acute pediatric asthma phenotypes using unsupervised machine learning

RATIONALE

More targeted management of severe acute pediatric asthma could improve clinical outcomes.

OBJECTIVES

To identify distinct clinical phenotypes of severe acute pediatric asthma using variables obtained in the first 12 h of hospitalization.

METHODS

We conducted a retrospective cohort study in a quaternary care children's hospital from 2014 to 2022. Encounters for children ages 2-18 years admitted to the hospital for asthma were included. We used consensus k means clustering with patient demographics, vital signs, diagnostics, and laboratory data obtained in the first 12 h of hospitalization.

MEASUREMENTS AND MAIN RESULTS

The study population included 683 encounters divided into derivation (80%) and validation (20%) sets, and two distinct clusters were identified. Compared to Cluster 1 in the derivation set, Cluster 2 encounters (177 [32%]) were older (11 years [8; 14] vs. 5 years [3; 8]; p < .01) and more commonly males (63% vs. 53%; p = .03) of Black race (51% vs. 40%; p = .03) with non-Hispanic ethnicity (96% vs. 84%; p < .01). Cluster 2 encounters had smaller improvements in vital signs at 12-h including percent change in heart rate (-1.7 [-11.7; 12.7] vs. -7.8 [-18.5; 1.7]; p < .01), and respiratory rate (0.0 [-20.0; 22.2] vs. -11.4 [-27.3; 9.0]; p < .01). Encounters in Cluster 2 had lower percentages of neutrophils (70.0 [55.0; 83.0] vs. 85.0 [77.0; 90.0]; p < .01) and higher percentages of lymphocytes (17.0 [8.0; 32.0] vs. 9.0 [5.3; 14.0]; p < .01). Cluster 2 encounters had higher rates of invasive mechanical ventilation (23% vs. 5%; p < .01), longer hospital length of stay (4.5 [2.6; 8.8] vs. 2.9 [2.0; 4.3]; p < .01), and a higher mortality rate (7.3% vs. 0.0%; p < .01). The predicted cluster assignments in the validation set shared the same ratio (~2:1), and many of the same characteristics.

CONCLUSIONS

We identified two clinical phenotypes of severe acute pediatric asthma which exhibited distinct clinical features and outcomes.

Causal inference can lead us to modifiable mechanisms and informative archetypes in sepsis

Medical progress is reflected in the advance from broad clinical syndromes to mechanistically coherent diagnoses. By this metric, research in sepsis is far behind other areas of medicine-the word itself conflates multiple different disease mechanisms, whilst excluding noninfectious syndromes (e.g., trauma, pancreatitis) with similar pathogenesis. New technologies, both for deep phenotyping and data analysis, offer the capability to define biological states with extreme depth. Progress is limited by a fundamental problem: observed groupings of patients lacking shared causal mechanisms are very poor predictors of response to treatment. Here, we discuss concrete steps to identify groups of patients reflecting archetypes of disease with shared underlying mechanisms of pathogenesis. Recent evidence demonstrates the role of causal inference from host genetics and randomised clinical trials to inform stratification analyses. Genetic studies can directly illuminate drug targets, but in addition they create a reservoir of statistical power that can be divided many times among potential patient subgroups to test for mechanistic coherence, accelerating discovery of modifiable mechanisms for testing in trials. Novel approaches, such as subgroup identification in-flight in clinical trials, will improve efficiency. Within the next decade, we expect ongoing large-scale collaborative projects to discover and test therapeutically relevant sepsis archetypes.

Stratification of Experimental LPS-Induced Systemic Inflammatory Response by Expression Level of Hif1a and NFkb Genes

It was previously found that the severity of LPS-induced systemic inflammatory response (SIRS) in rats is determined by resistance to hypoxia and the level of Hif1a expression. Individual differences in the level of Hif1a and NFkb expression in the liver were studied in relation to the severity of inflammatory and immune reactions in LPS-induced SIRS in rats without previous placement in a ventilated decompression chamber. During the early periods after SIRS modeling, rats with high expression of the Hif1a and NFkb genes associated with increased expression of pro- and anti-inflammatory cytokines are identified. These animals have a high blood level of corticosterone, low number of neutrophils in the interalveolar septa, and a predominance of T cells over B cells in the peripheral blood. The obtained data can be used to develop new approaches to the individual prediction of the severity of sepsis and SIRS in intensive care units, which will increase the effectiveness of therapy and reduce mortality rate.

International multi-cohort analysis identifies novel framework for quantifying immune dysregulation in critical illness: results of the SUBSPACE consortium

Progress in the management of critical care syndromes such as sepsis, Acute Respiratory Distress Syndrome (ARDS), and trauma has slowed over the last two decades, limited by the inherent heterogeneity within syndromic illnesses. Numerous immune endotypes have been proposed in sepsis and critical care, however the overlap of the endotypes is unclear, limiting clinical translation. The SUBSPACE consortium is an international consortium that aims to advance precision medicine through the sharing of transcriptomic data. By evaluating the overlap of existing immune endotypes in sepsis across over 6,000 samples, we developed cell-type specific signatures to quantify dysregulation in these immune compartments. Myeloid and lymphoid dysregulation were associated with disease severity and mortality across all cohorts. This dysregulation was not only observed in sepsis but also in ARDS, trauma, and burn patients, indicating a conserved mechanism across various critical illness syndromes. Moreover, analysis of randomized controlled trial data revealed that myeloid and lymphoid dysregulation is linked to differential mortality in patients treated with anakinra or corticosteroids, underscoring its prognostic and therapeutic significance. In conclusion, this novel immunology-based framework for quantifying cellular compartment dysregulation offers a valuable tool for prognosis and therapeutic decision-making in critical illness.

Utility of plasma suPAR to identify AKI and sepsis associated AKI in critically ill children

Current biomarkers for sepsis-associated acute kidney injury (SA-AKI) lack specificity. The role of soluble urokinase plasminogen activator receptor (suPAR) in discriminating AKI and SA-AKI in children remains elusive. This prospective multicenter study was conducted in critically ill children cohorts using a derivation-validation design, and plasma samples were collected within first 24 h after admission. Plasma suPAR was independently associated with AKI, SA-AKI, and PICU mortality, even after adjustment for confounding variables. This multiclass classification model had the micro-average AUC of 0.89 with specificity of 97.6% for discriminating non-septic AKI, and specificity of 99.0% for discriminating SA-AKI, based on the cut-off values of 1.5 and 2.3-fold baseline in serum creatinine (SCr) and 4.5 and 11.2 ng/mL in plasma suPAR. The multiclass classification model provides the cutoffs for plasma suPAR and SCr and specifically discriminates critically ill children at high risk of non-septic AKI and SA-AKI, which can facilitate clinical utility.

Huperzine a ameliorates sepsis-induced acute lung injury by suppressing inflammation and oxidative stress via α7 nicotinic acetylcholine receptor

Sepsis, characterized by high mortality rates, causes over 50 % of acute lung injury (ALI) cases, primarily due to the heightened susceptibility of the lungs during this condition. Suppression of the excessive inflammatory response is critical for improving the survival of patients with sepsis; nevertheless, no specific anti-sepsis drugs exist. Huperzine A (HupA) exhibits neuroprotective and anti-inflammatory properties; however, its underlying mechanisms and effects on sepsis-induced ALI have yet to be elucidated. In this study, we demonstrated the potential of HupA for treating sepsis and explored its mechanism of action. To investigate the in vivo impacts of HupA, a murine model of sepsis was induced through cecal ligation and puncture (CLP) in both wild-type (WT) and α7 nicotinic acetylcholine receptor (α7nAChR) knockout mice. Our results showed that HupA ameliorates sepsis-induced acute lung injury by activating the α7nAChR. We used the CLP sepsis model in wild-type and α7nAChR -/- mice and found that HupA significantly increased the survival rate through α7nAChR, reduced the pro-inflammatory cytokine levels and oxidative stress, ameliorated histopathological lung injury, altered the circulating immune cell composition, regulated gut microbiota, and promoted short-chain fatty acid production through α7nAChR in vivo. Additionally, HupA inhibited Toll-like receptor NF-κB signaling by upregulating the α7nAChR/protein kinase B/glycogen synthase kinase-3 pathways. Our data elucidate HupA's mechanism of action and support a "new use for an old drug" in treating sepsis. Our findings serve as a basis for further in vivo studies of this drug, followed by application to humans. Therefore, the findings have the potential to benefit patients with sepsis.

Diagnostic Validation of the Updated Pediatric Sepsis Biomarker Risk II for Acute Kidney Injury Prediction Model in Pediatric Septic Shock

OBJECTIVES

We previously derived the updated Pediatric Sepsis Biomarker Risk for Acute Kidney Injury (PERSEVERE-II AKI) prediction model, which had robust diagnostic test characteristics for severe AKI on day 3 (D3 severe AKI) of septic shock. We now sought to validate this model in an independent cohort of children to the one in which the model was developed.

DESIGN

A secondary analysis of a multicenter, prospective, observational study carried out from January 2019 to December 2022.

SETTING

Ten PICUs in the United States.

PATIENTS

Children with septic shock 1 week to 18 years old admitted to the PICU.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Seventy-nine of 363 patients (22%) had D3 severe AKI, defined as Kidney Disease Improving Global Outcomes stage 2 or higher. Patients were assigned a probability of D3 severe AKI using the PERSEVERE-II AKI model. The model predicted D3 severe AKI with an area under the receiver operating characteristic curve of 0.89 (95% CI, 0.85-0.93), sensitivity of 77% (95% CI, 66-86%), specificity of 88% (95% CI, 84-92%), positive predictive value of 65% (95% CI, 54-74%), and negative predictive value of 93% (95% CI, 89-96%). These data represent an increase in post-test probability of D3 severe AKI with a positive test from 22% to 65%, and a prevalence threshold of 28%. On multivariable regression, the PERSEVERE-II AKI prediction model demonstrated greater adjusted odds ratio (aOR) for D3 severe AKI (aOR, 11.2; 95% CI, 4.9-25.3) and lesser aOR for failure of D3 renal recovery from early AKI (aOR, 0.31; 95% CI, 0.13-0.69).

CONCLUSIONS

The PERSEVERE-II AKI model demonstrates consistently robust performance for prediction of new or persistent D3 severe AKI in children with septic shock. A major limitation is that actual D3 severe AKI prevalence is below the prevalence threshold for the test, and thus future work should focus on evaluating use in enriched populations.

Shadows and lights in sepsis immunotherapy

INTRODUCTION

Sepsis remains a major global public health challenge. The host's response in sepsis involves both an exaggerated inflammatory reaction and immunosuppressive mechanisms. A better understanding of this response has shed light on the failure of anti-inflammatory therapies administered under the 'one size fits all' approach during the last decades.

AREAS COVERED

To date, patients' management has moved toward a comprehensive precision medicine approach that aims to personalize immunotherapy, whether anti-inflammatory or immunostimulatory. Large Prospective interventional randomized controlled trials validating this approach are about to start. A crucial prerequisite for these studies is to stratify patients based on biomarkers that will help defining the patients' immuno-inflammatory trajectory.

EXPERT OPINION

Some biomarkers are already available in routine clinical care, while improvements are anticipated through the standardized use of transcriptomics and other multi-omics technologies in this field. With these precautions in mind, it is reasonable to anticipate improvement in outcomes in sepsis.

Identification of key biomarkers and therapeutic targets in sepsis through coagulation-related gene expression and immune pathway analysis

Sepsis, characterized by a widespread and dysregulated immune response to infection leading to organ dysfunction, presents significant challenges in diagnosis and treatment. In this study, we investigated 203 coagulation-related genes in sepsis patients to explore their roles in the disease. Through differential gene expression analysis, we identified 20 genes with altered expression patterns. Subsequent correlation analysis, visualized through circos plots and heatmaps, revealed significant relationships among these genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses indicated that these genes are involved in immune response activation, coagulation, and immune receptor activity. Disease Ontology (DO) enrichment analysis further linked these genes to autoimmune hemolytic anemia and tumor-related signaling pathways. Additionally, the CIBERSORT analysis highlighted differences in immune cell composition in sepsis patients, revealing an increase in neutrophils and monocytes and a decrease in inactive NK cells, CD8 T cells, and B cells. We employed machine learning techniques, including random forest and SVM, to construct a diagnostic model, identifying FCER1G and FYN as key biomarkers. These biomarkers were validated through their expression levels and ROC curve analysis in an independent validation cohort, demonstrating strong diagnostic potential. Single-cell analysis from the GSE167363 dataset further confirmed the distinct expression profiles of these genes across various cell types, with FCER1G predominantly expressed in monocytes, NK cells, and platelets, and FYN in CD4+ T cells and NK cells. Enrichment analysis via GSEA and ssGSEA revealed that these genes are involved in critical pathways, including intestinal immune networks, fatty acid synthesis, and antigen processing. In conclusion, our comprehensive analysis identifies FCER1G and FYN as promising biomarkers for sepsis, providing valuable insights into the molecular mechanisms of this complex condition. These findings offer new avenues for the development of targeted diagnostic and therapeutic strategies in sepsis management.

Role of pyruvate kinase M2 in regulating sepsis (Review)

Glycolysis occurs in all living organisms as a form of energy supply. Pyruvate kinase M2 (PKM2) is one of the rate‑limiting enzymes in the glycolytic process. PKM2 is considered to serve an important role in several terminal diseases, including sepsis. However, to the best of our knowledge, the specific mechanistic role of PKM2 in sepsis remains to be systematically summarised. Therefore, the present review aims to summarise the roles of PKM2 in sepsis progression. In addition, potential treatment strategies for patients with sepsis are discussed. The present review hopes to lay the groundwork for studying the role of PKM2 and developing therapeutic strategies against metabolic disorders that occur during sepsis.

The Precision Resuscitation With Crystalloids in Sepsis (PRECISE) Trial: A Trial Protocol

Importance

Intravenous fluids are an essential part of treatment in sepsis, but there remains clinical equipoise on which type of crystalloid fluids to use in sepsis. A previously reported sepsis subphenotype (ie, group D) has demonstrated a substantial mortality benefit from balanced crystalloids compared with normal saline.

Objective

To test the hypothesis that targeting balanced crystalloids to patients with group D sepsis through an electronic health record (EHR) alert will reduce 30-day inpatient mortality.

Design, Setting, and Participants

The Precision Resuscitation With Crystalloids in Sepsis (PRECISE) trial is a parallel-group, multihospital, single-blind, pragmatic randomized clinical trial to be conducted at 6 hospitals in the Emory Healthcare system. Patients with suspicion of group D infection in whom a clinician initiates an order for normal saline in the emergency department (ED) or intensive care unit (ICU) will be randomized to usual care and intervention arms.

Intervention

An EHR alert that appears in the ED and ICUs to nudge clinicians to use balanced crystalloids instead of normal saline.

Main Outcomes and Measures

The primary outcome is 30-day inpatient mortality. Secondary outcomes are ICU admission, in-hospital mortality, receipt of vasoactive drugs, receipt of new kidney replacement therapy, and receipt of mechanical ventilation (vasoactive drugs, kidney replacement therapy, and mechanical ventilation are counted if they occur after randomization and within the 30-day study period). Intention-to-treat analysis will be conducted.

Discussion

The PRECISE trial may be one of the first precision medicine trials of crystalloid fluids in sepsis. Using routine vital signs (temperature, heart rate, respiratory rate, and blood pressure), available even in low-resource settings, a validated machine learning algorithm will prospectively identify and enroll patients with group D sepsis who may have a substantial mortality reduction from used of balanced crystalloids compared with normal saline.

Results

On finalizing participant enrollment and analyzing the data, the study's findings will be shared with the public through publication in a peer-reviewed journal.

Conclusions

With use of a validated machine learning algorithm, precision resuscitation in sepsis could fundamentally redefine international standards for intravenous fluid resuscitation.

Trial Registration

ClinicalTrials.gov Identifier: NCT06253585.

Novel cortisol trajectory sub-phenotypes in sepsis

BACKGROUND

Sepsis is a heterogeneous syndrome. This study aimed to identify new sepsis sub-phenotypes using plasma cortisol trajectory.

METHODS

This retrospective study included patients with sepsis admitted to the intensive care unit of Zhongshan Hospital Fudan University between March 2020 and July 2022. A group-based cortisol trajectory model was used to classify septic patients into different sub-phenotypes. The clinical characteristics, biomarkers, and outcomes were compared between sub-phenotypes.

RESULTS

A total of 258 patients with sepsis were included, of whom 186 were male. Patients were divided into two trajectory groups: the lower-cortisol group (n = 217) exhibited consistently low and slowly declining cortisol levels, while the higher-cortisol group (n = 41) showed relatively higher levels in comparison. The 28-day mortality (65.9% vs.16.1%, P < 0.001) and 90-day mortality (65.9% vs. 19.8%, P < 0.001) of the higher-cortisol group were significantly higher than the lower-cortisol group. Multivariable Cox regression analysis showed that the trajectory sub-phenotype (HR = 5.292; 95% CI 2.218-12.626; P < 0.001), APACHE II (HR = 1.109; 95% CI 1.030-1.193; P = 0.006), SOFA (HR = 1.161; 95% CI 1.045-1.291; P = 0.006), and IL-1β (HR = 1.001; 95% CI 1.000-1.002; P = 0.007) were independent risk factors for 28-day mortality. Besides, the trajectory sub-phenotype (HR = 4.571; 95% CI 1.980-10.551; P < 0.001), APACHE II (HR = 1.108; 95% CI 1.043-1.177; P = 0.001), SOFA (HR = 1.270; 95% CI 1.130-1.428; P < 0.001), and IL-1β (HR = 1.001; 95% CI 1.000-1.001; P = 0.015) were also independent risk factors for 90-day mortality.

CONCLUSION

This study identified two novel cortisol trajectory sub-phenotypes in patients with sepsis. The trajectories were associated with mortality, providing new insights into sepsis classification.

Towards improved point-of-care (POC) testing for patients with suspected sepsis: POC tests for host biomarkers and possible microbial pathogens

INTRODUCTION

Sepsis is a heterogeneous syndrome often misdiagnosed. Point-of-care (POC) diagnostic tests are commonly used to guide decision and include host biomarkers and molecular diagnostics.

AREAS COVERED

The diagnostic and prognostic accuracy of established and emerging biomarkers for sepsis, including procalcitonin (PCT) soluble urokinase plasminogen activator receptor (suPAR), presepsin, TRAIL/IP-10/CRP, MxA, and MxA-CRP, are analyzed in this review. The clinical utility of the two prevalent molecular techniques for pathogens identification using polymerase chain reaction (PCR) assays is also presented: FILMARRAY and QIAstat-Dx RP.

EXPERT OPINION

The rising benefits of the combined use of POC biomarkers with molecular diagnostics in daily clinical routine appear to outperform conventional practices in terms of reduced turnaround time, timely diagnosis, and prompt administration of the appropriate treatment. Yet, this must be further demonstrated in future investigations. However, the cost-effectiveness of POC tests and the high rate of false positive and negative results, indicate the need for a comprehensive clinical evaluation.