Global, regional, and national sepsis incidence and mortality, 1990-2017: analysis for the Global Burden of Disease Study

Jinhong decoction ameliorates injury in septic mice without disrupting the equilibrium of gut microbiota

Sepsis is a life-threatening condition and usually be treated with antibiotics, which however often has severe side effects. This work proposed a novel Chinese traditional medicine JINHONG (JH) decoction for therapy of sepsis. We first identified the chemical constituents of JH decoction by using high-performance liquid chromatography and mass spectrometry (HPLC-MS). Then, we constructed a model mouse for sepsis by using cecal ligation and puncture (CLP). Metagenomic sequencing method was used to compare the diversity and abundance of the gut microbiota between normal, disease model, JH decoction-treatment and antibiotic-treatment mice. Many indices including the number of platelets, CD62p and CD63 content, AQP2 and AQP8 level, as well as the expression level of protein C confirmed that the sepsis resulted in serious pathological damage, while all of these indices could be reversed by JH decoction and antibiotics. The diversity and abundance of intestinal flora decreased in CLP mice, and the decrements aggravated after antibiotic treatment while can be recovered by JH decoction treatment. The abundance of anti-inflammatory Ruminococcaceae increased after JH decoction treatment, indicating that JH decoction could ameliorate pathology associated with sepsis in CLP model via modulating the intestinal flora. This study demonstrates that JH decoction could treat sepsis clinically without obvious adverse effects on gut microbiota.

Echinocystic acid inhibits sepsis-associated renal inflammation and apoptosis by targeting protein tyrosine phosphatase 1B

Thefruits of Gleditsia sinensis Lam. have been utilized to treat inflammatory diseases in China. Echinocystic acid (EA), one pentacyclic triterpenoid isolated from thefruits of G. sinensis, exhibits an anti-inflammatory effect. However, its anti-sepsis activity and mechanism of action, especially the protective effect against sepsis-associated acute kidney injury (SA-AKI), are not investigated yet. This study is to explore the efficacy and potential mechanism of EA on SA-AKI. EA elevated the function of multiple organs and effectively reduced the increased inflammation and apoptosis of kidney tissue and HK-2 cells. DARTS, CETSA, and molecular docking experiments revealed that EA could directly bind to protein tyrosine phosphatase 1B (PTP1B), a widespread prototype non-receptor tyrosine phosphatase. Collectively, EA can alleviate murine SA-AKI though restraining inflammation and apoptosis and may be a potential natural drug for remedying SA-AKI.

Could P2X7 receptor be a potencial target in neonatal sepsis?

The United Nations Inter-Agency Group for Child Mortality Estimation (UNIGME) estimates that every year 2.5 million neonates die in their first month of life, accounting for nearly one-half of deaths in children under 5 years of age. Neonatal sepsis is the third leading cause of neonatal mortality. The worldwide burden of bacterial sepsis is expected to increase in the next decades due to the lack of effective molecular therapies to replace the administration of antibiotics whose efficacy is compromised by the emergence of resistant strains. In addition, prolonged exposure to antibiotics can have negative effects by increasing the risk of infection by other organisms. With the global burden of sepsis increasing and no vaccine nor other therapeutic approaches proved efficient, the World Health Organization (WHO) stresses the need for new therapeutic targets for sepsis treatment and infection prevention (WHO, A73/32). In response to this unresolved clinical issue, the P2X7 receptor (P2X7R), a key component of the inflammatory cascade, has emerged as a potential target for treating inflammatory/infection diseases. Indeed numerous studies have demonstrated the relevance of the purinergic system as a pharmacological target in addressing immune-mediated inflammatory diseases by regulating immunity, inflammation, and organ function. In this review, we analyze key features of sepsis immunopathophysiology focusing in neonatal sepsis and on how the immunomodulatory role of P2X7R could be a potential pharmacological target for reducing the burden of neonatal sepsis.

Medicinal evaluation and molecular docking study of osajin as an anti-inflammatory, antioxidant, and antiapoptotic agent against sepsis-associated acute kidney injury in rats

Despite efforts to find effective drugs for sepsis-associated acute kidney injury (SA-AKI), mortality rates in patients with SA-AKI have not decreased. Our study evaluated the protective effects of isoflavone osajin (OSJ) on SA-AKI in rats by targeting inflammation, oxidative stress, and apoptosis, which represent the cornerstones in the pathophysiological mechanism of SA-AKI. Polymicrobial sepsis was induced in rats via the cecal ligation and puncture (CLP) technique. Markers of oxidative stress were evaluated in kidney tissues using biochemical methods. The expression of interleukin-33 (IL-33), 8-hydroxydeoxyguanosine (8-OHdG), caspase-3, and kidney injury molecule-1 (KIM-1) was evaluated as indicators of inflammation, DNA damage, apoptosis, and SA-AKI respectively in the kidney tissues using immunohistochemical and immunofluorescent detection methods. The CLP technique significantly (p < 0.001) increased lipid peroxidation (LPO) levels and significantly (p < 0.001) decreased the activities of superoxide dismutase and catalase in kidney tissues. In the renal tissues, strong expression of IL-33, 8-OHdG, caspase-3, and KIM-1 was observed with severe degeneration and necrosis in the tubular epithelium and intense interstitial nephritis. In contrast, the administration of OSJ significantly (p < 0.001) reduced the level of LPO, markedly improved biomarkers of antioxidant status, decreased the levels of serum creatinine and urea, lowered the expression of IL-33, 8-OHdG, caspase-3, and KIM-1 and alleviated changes in renal histopathology. A promising binding score was found via a molecular docking investigation of the OSJ-binding mode with mouse IL-33 (PDB Code: 5VI4). Therefore, OSJ protects against SA-AKI by suppressing the IL-33/LPO/8-OHdG/caspase-3 pathway and improving the antioxidant system.

Association between the triglyceride glucose index and short-term mortality in septic patients with or without obesity: a retrospective cohort study

BACKGROUND

Sepsis is a significant contributor to both intensive care unit (ICU) admissions and mortality among patients in ICU, with a rising prevalence of obesity. There is a lack of extensive research on the correlation between TyGI and findings in patients with sepsis, especially in obese patients.

METHODS

This study used a retrospective cohort design and included patients with sepsis (≥18 years) from the Medical Information Mart for Intensive Care IV database. The association between TyGI and outcome was examined using multivariable logistic regression analysis.

RESULTS

8,840 patients with sepsis were included in the analysis. The in-ICU mortality rate was 9.7%. Non-survivors exhibited significantly greater TyGI levels than survivors [9.19(8.76-9.71) vs. 9.10(8.67-9.54), p < 0.001]. The adjusted multivariate regression model showed that elevated TyGI values were linked to a greater likelihood of death in ICU (odds ratio [OR] range 1.072-1.793, p < 0.001) and hospital (OR range 1.068-1.445, p = 0.005). Restricted Cubic Spline analysis revealed a nonlinear association between TyGI and in-ICU and in-hospital mortality risks within specified ranges. Subgroup analysis revealed interaction effects in the general obesity, abdominal obesity, and impaired fasting glucose subgroups (p = 0.014, 0.016, and < 0.001, respectively).

CONCLUSION

TyGI was associated with an increased sepsis-related short-term mortality risk and adverse outcomes after ICU admission.

Influence of contrast medium on long-term renal function and outcomes in patients with septic acute kidney injury: A propensity-matched cohort study

PURPOSE

To investigate the relationship between contrast medium administration and long-term mortality and renal function in patients with septic acute kidney injury (AKI).

MATERIALS AND METHODS

We performed a retrospective, propensity-matched cohort study involving 1521 adult patients admitted with septic shock. Patients with septic AKI who underwent contrast or non-contrast CT scans were enrolled. The primary outcomes were the rates of 90-day mortality and dialysis within 90 days. The secondary outcomes included worsening of AKI, in-hospital mortality, and maintenance of dialysis after 90 days.

RESULTS

During the study period, 609 patients with septic AKI were identified; 220 (36.1%) underwent contrast CT and 389 (63.9%) underwent non-contrast CT. After propensity score matching, 133 pairs were obtained. There were no significant differences between the contrast and non-contrast CT groups in 90-day mortality (54.9% vs. 58.6%, P = 0.579), dialysis within 90 days (6.8% vs. 8.3%, P = 0.655), worsening AKI (2.3% vs. 3.0%, P = 0.706), in-hospital mortality (10.6% vs. 14.4%, P = 0.369), or maintenance of dialysis after 90 days (0.0% vs. 0.8%, P > 0.99).

CONCLUSIONS

The administration of intravenous contrast medium was not associated with long-term mortality, deterioration of renal function, or dialysis in patients with septic AKI.

Simulating the clinical manifestations and disease progression of human sepsis: A monobacterial injection approach for animal modeling

Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection, with great clinical heterogeneity, high morbidity, and high mortality. At the same time, there are many kinds of infection sources, the pathophysiology is very complex, and the pathogenesis has not been fully elucidated. An ideal animal model of sepsis can accurately simulate clinical sepsis and promote the development of sepsis-related pathogenesis, treatment methods, and prognosis. The existing sepsis model still uses the previous Sepsis 2.0 modelling standard, which has some problems, such as many kinds of infection sources, poor repeatability, inability to take into account single-factor studies, and large differences from clinical sepsis patients. To solve these problems, this study established a new animal model of sepsis. The model uses intravenous tail injection of a single bacterial strain, simplifying the complexity of multibacterial infection, and effectively solving the above problems.

Glucocorticoid therapy for sepsis in the AI era: a survey on current and future approaches

Sepsis, a life-threatening medical condition, manifests as new or worsening organ failures due to a dysregulated host response to infection. Many patients with sepsis have manifested a hyperinflammatory phenotype leading to the identification of inflammatory modulation by corticosteroids as a key treatment modality. However, the optimal use of corticosteroids in sepsis treatment remains a contentious subject, necessitating a deeper understanding of their physiological and pharmacological effects. Our study conducts a comprehensive review of randomized controlled trials (RCTs) focusing on traditional corticosteroid treatment in sepsis, alongside an analysis of evolving clinical guidelines. Additionally, we explore the emerging role of artificial intelligence (AI) in medicine, particularly in diagnosing, prognosticating, and treating sepsis. AI's advanced data processing capabilities reveal new avenues for enhancing corticosteroid therapeutic strategies in sepsis. The integration of AI in sepsis treatment has the potential to address existing gaps in knowledge, especially in the application of corticosteroids. Our findings suggest that combining corticosteroid therapy with AI-driven insights could lead to more personalized and effective sepsis treatments. This approach holds promise for improving clinical outcomes and presents a significant advancement in the management of this complex and often fatal condition.

Machine learning for predicting mortality in adult critically ill patients with Sepsis: A systematic review

INTRODUCTION

Various Machine Learning (ML) models have been used to predict sepsis-associated mortality. We conducted a systematic review to evaluate the methodologies employed in studies to predict mortality among patients with sepsis.

METHODS

Following a pre-established protocol registered at the International Prospective Register of Systematic Reviews, we performed a comprehensive search of databases from inception to February 2024. We included peer-reviewed articles reporting predicting mortality in critically ill adult patients with sepsis.

RESULTS

Among the 1822 articles, 31 were included, involving 1,477,200 adult patients with sepsis. Nineteen studies had a high risk of bias. Among the diverse ML models, Logistic regression and eXtreme Gradient Boosting were the most frequently used, in 22 and 16 studies, respectively. Nine studies performed internal and external validation. Compared with conventional scoring systems such as SOFA, the ML models showed slightly higher performance in predicting mortality (AUROC ranges: 0.62-0.90 vs. 0.47-0.86).

CONCLUSIONS

ML models demonstrate a modest improvement in predicting sepsis-associated mortality. The certainty of these findings remains low due to the high risk of bias and significant heterogeneity. Studies should include comprehensive methodological details on calibration and hyperparameter selection, adopt a standardized definition of sepsis, and conduct multicenter prospective designs along with external validations.

Contributions of individual qSOFA elements to assessment of severity and for prediction of mortality

BACKGROUND

The quick sequential [sepsis-related] organ failure assessment (qSOFA) acts as a prompt to consider possible sepsis. The contributions of individual qSOFA elements to assessment of severity and for prediction of mortality remain unknown.

METHODS

A total of 3974 patients with community-acquired pneumonia were recruited to an observational prospective cohort study. The area under the receiver operating characteristic curve (AUROC), odds ratio, relative risk and Youden's index were employed to assess discrimination.

RESULTS

Respiratory rate ≥22/min demonstrated the most superior diagnostic value, indicated by largest odds ratio, relative risk and AUROC, and maximum Youden's index for mortality. However, the indices for altered mentation and systolic blood pressure (SBP) ≤100 mm Hg decreased notably in turn. The predictive validities of respiratory rate ≥22/min, altered mentation and SBP ≤100 mm Hg were good, adequate and poor for mortality, indicated by AUROC (0.837, 0.734 and 0.671, respectively). Respiratory rate ≥22/min showed the strongest associations with SOFA scores, pneumonia severity index, hospital length of stay and costs. However, SBP ≤100 mm Hg was most weakly correlated with the indices.

CONCLUSIONS

Respiratory rate ≥22/min made the greatest contribution to parsimonious qSOFA to assess severity and predict mortality. However, the contributions of altered mentation and SBP ≤100 mm Hg decreased strikingly in turn. It is the first known prospective evidence of the contributions of individual qSOFA elements to assessment of severity and for prediction of mortality, which might have implications for more accurate clinical triage decisions.

Systematic analysis based on bioinformatics and experimental validation identifies Alox5 as a novel therapeutic target of quercetin for sepsis

PURPOSE

This study investigated the molecular mechanism of quercetin in the treatment of sepsis using network pharmacological prediction and experimentation.

METHODS

Hub genes were identified by intersecting the differentially expressed genes (DEGs) of the GSE131761 and GSE9960 databases with genes from the hub modules of Weighted Gene Co-Expression Network Analysis (WGCNA), targets of quercetin, and ferroptosis. Subsequently, in order to determine the functional characteristics and molecular link of hub gene obtained above, we redetermined the hub-DEGs in GSE131761 according to high or low hub gene expression. Afterward, the main pathways of enrichment analysis were validated using these hub-DEGs. Finally, an experiment was conducted to validate the findings.

RESULTS

By intersecting 1415 DEGs in GSE131761, 543 DEGs in GSE9960, 5784 key modular genes, 470 ferroptosis-related genes, and 154 quercetin-related genes, we obtained one quercetin-related gene, Alox5. Subsequently, 340 hub-DEGs were further validated according to high or low Alox5 expression. The results of the enrichment analysis revealed that hub-DEGs were mainly associated with inflammation and the immune response. Immune infiltration analysis showed that higher expression of Alox5 was related to macrophage infiltration and could be a predictor of diagnosis in patients with sepsis. The expression pattern of Alox5 was then depicted and the upregulation of Alox5 in the vital organs of septic mice was further demonstrated. In vitro and in vivo experiments showed that upregulation of Alox5 and inflammation-related cytokines induced by sepsis could be inhibited by quercetin (p < 0.05).

CONCLUSIONS

Alox5 may be involved in the occurrence and development of multi-organ functional disturbances in sepsis and is a reliable target of quercetin against sepsis.

Relationship between thrombocytopenia and prognosis in children with septic shock: a retrospective cohort study

Septic shock is a life-threatening disease worldwide often associated with thrombocytopenia. Platelets play a crucial role in bridging the gap between immunity, coagulation, and endothelial cell activation, potentially influencing the course of the disease. However, there are few studies specifically evaluating the impact of thrombocytopenia on the prognosis of pediatric patients. Therefore, the study investigates effects of early thrombocytopenia in the prognosis of children with septic shock. Pediatric patients with septic shock from 2015 to 2022 were included monocentrically. Thrombocytopenia was defined as a platelet count of <100 × 109/L during the first 24 hours of septic shock onset. The primary outcome was the 28-day mortality. Propensity score matching was used to pair patients with different platelet counts on admission but comparable disease severity. A total of 419 pediatric patients were included in the analysis. Patients with thrombocytopenia had higher 28-day mortality (55.5% vs. 38.7%, p = .005) compared to patients with no thrombocytopenia. Thrombocytopenia was associated with reduced 28-PICU free days (median value, 0 vs. 13 days, p = .003) and 28-ventilator-free (median value, 0 vs. 19 days, p = .001) days. Among thrombocytopenia patients, those with platelet count ≤50 × 109/L had a higher 28-day mortality rate (63.6% vs. 45%, p = .02). Multiple logistic regression showed that elevated lactate (adjusted odds ratio (OR) = 1.11; 95% confidence interval (CI): 1.04-1.17; P <0.001) and white blood cell (WBC) count (OR = 0.97; 95% CI: 0.95-0.99; p = .003) were independent risk factors for the development of thrombocytopenia. Thrombocytopenia group had increased bleeding events, blood product transfusions, and development of organ failure. In Kaplan-Meier survival estimates, survival probabilities at 28 days were greater in patients without thrombocytopenia (p value from the log-rank test, p = .004). There were no significant differences in the type of pathogenic microorganisms and the site of infection between patients with and without thrombocytopenia. In conclusion, thrombocytopenia within 24 hours of shock onset is associated with an increased risk of 28-day mortality in pediatric patients with septic shock.

Predictive models of sepsis-associated acute kidney injury based on machine learning: a scoping review

BACKGROUND

With the development of artificial intelligence, the application of machine learning to develop predictive models for sepsis-associated acute kidney injury has made potential breakthroughs in early identification, grading, diagnosis, and prognosis determination.

METHODS

Here, we conducted a systematic search of the PubMed, Cochrane Library, Embase (Ovid), Web of Science, and Scopus databases on April 28, 2023, and screened relevant literature. Then, we comprehensively extracted relevant data related to machine learning algorithms, predictors, and predicted objectives. We subsequently performed a critical evaluation of research quality, data aggregation, and analyses.

RESULTS

We screened 25 studies on predictive models for sepsis-associated acute kidney injury from a total of originally identified 2898 studies. The most commonly used machine learning algorithm is traditional logistic regression, followed by eXtreme gradient boosting. We categorized these predictive models into early identification models (60%), prognostic prediction models (32%), and subtype identification models (8%) according to their predictive purpose. The five most commonly used predictors were serum creatinine levels, lactate levels, age, blood urea nitrogen concentration, and diabetes mellitus. In addition, a single data source, insufficient assessment of clinical utility, lack of model bias assessment, and hyperparameter adjustment may be the main reasons for the low quality of the current research.

CONCLUSIONS

However, studies on the nondeath prognostic outcomes, the long-term clinical outcomes, and the subtype identification models are insufficient. Additionally, the poor quality of the research and the insufficient practicality of the model are problems that need to be addressed urgently.

Single-cell RNA sequencing and immune repertoire analysis revealed dynamic immune characteristics associated with peripheral blood during sepsis

Sepsis is a potentially fatal condition arising from an abnormal immune response to an infection, which can result in organ failure and even death. To explore the mechanism underlying the dysregulated immune response during sepsis and identify potential therapeutic targets, single-cell RNA sequencing (scRNA-seq) and immune repertoire analysis were conducted to depict the cellular landscape of peripheral blood cells in septic mice. We observed significant alterations in the number and proportion of peripheral blood cell populations driven by sepsis. By combining single-cell gene expression profiles and B cell receptor (BCR) repertoire analysis, we discerned that infection inflicted serious damage on the antigen presentation ability of B cells and the diversity of BCR in a short time. In addition, we found that the cecal ligation and puncture procedure in mice inhibited the communication signals of CD4+ and CD8+ T cells and decreased the interactions between B cells and other cells. Our study provides detailed insights into the dynamic changes in the biological characteristics of peripheral blood cells driven by sepsis and provides important advances in our understanding of immune disorders during sepsis.

Combining Aloin with TIENAM ameliorates cecal ligation and puncture-induced sepsis in mice by attenuating inflammation and modulating abdominal cavity microbiota

Despite the high mortality rate, sepsis lacks specific and effective treatment options. Conventional antibiotics, such as TIENAM (TIE; imipenem and cilastatin sodium for injection), face challenges owing to the emergence of bacterial resistance, which reduces their effectiveness and causes adverse effects. Addressing resistance and judicious drug use is crucial. Our research revealed that aloin (Alo) significantly boosts survival rates and reduces inflammation and bacterial load in mice with sepsis, demonstrating strong antimicrobial activity. Using a synergistic Alo + TIE regimen in a cecal ligation and puncture (CLP)-induced sepsis model, we observed a remarkable increase in survival rates from 10 % to 75 % within 72 h compared with the CLP group alone. This combination therapy also modulated inflammatory markers interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α, mitigated tissue damage, regulated immune cells by lowering NK, activated CD8+ and CD4+ T cells while increasing peritoneal macrophages, and decreased the bacterial load in the peritoneal cavity. We noted a significant shift in the abdominal cavity microbiota composition post-treatment, with a decrease in harmful bacteria, such as Lachnospiraceae_NK4A136_group, Klebsiella, Bacillus, and Escherichia, and an increase in beneficial bacteria, such as Lactobacillus and Mucispirillum. Our study emphasizes the efficacy of combining Alo with TIE to combat sepsis, and paves the way for further investigations and potential clinical applications aiming to overcome the limitations of TIE and enhance the therapeutic prospects of Alo.

Combining ulinastatin with TIENAM improves the outcome of sepsis induced by cecal ligation and puncture in mice by reducing inflammation and regulating immune responses

Despite the high mortality associated with sepsis, effective and targeted treatments remain scarce. The use of conventional antibiotics such as TIENAM (imipenem and cilastatin sodium for injection, TIE) is challenging because of the increasing bacterial resistance, which diminishes their efficacy and leads to adverse effects. Our previous studies demonstrated that ulinastatin (UTI) exerts a therapeutic impact on sepsis by reducing systemic inflammation and modulating immune responses. In this study, we examined the possibility of administering UTI and TIE after inducing sepsis in a mouse model using cecal ligation and puncture (CLP). We assessed the rates of survival, levels of inflammatory cytokines, the extent of tissue damage, populations of immune cells, microbiota in ascites, and important signaling pathways. The combination of UTI and TIE significantly improved survival rates and reduced inflammation and bacterial load in septic mice, indicating potent antimicrobial properties. Notably, the survival rates of UTI+TIE-treated mice increased from 10 % to 75 % within 168 h compared to those of mice that were subjected to CLP. The dual treatment successfully regulated the levels of inflammatory indicators (interleukin [IL]-6, IL-1β, and tumor necrosis factor [TNF]-α) and immune cell numbers by reducing B cells, natural killer cells, and TNFR2+ Treg cells and increasing CD8+ T cells. Additionally, the combination of UTI and TIE alleviated tissue damage, reduced bacterial load in the peritoneal cavity, and suppressed the NF-κB signaling pathway. Our findings indicate that UTI and TIE combination therapy can significantly enhance sepsis outcomes by reducing inflammation and boosting the immune system. The results offer a promising therapeutic approach for future sepsis treatment.

Endothelial α1-adrenergic receptor activation improves cardiac function in septic mice via PKC-ERK/p38MAPK signaling pathway

Cardiomyopathy is particularly common in septic patients. Our previous studies have shown that activation of the alpha 1 adrenergic receptor (α1-AR) on cardiomyocytes inhibits sepsis-induced myocardial dysfunction. However, the role of cardiac endothelial α1-AR in septic cardiomyopathy has not been determined. Here, we identified α1-AR expression in mouse and human endothelial cells and showed that activation of α1-AR with phenylephrine (PE) improved cardiac function and survival by preventing cardiac endothelial injury in septic mice. Mechanistically, activating α1-AR with PE decreased the expression of ICAM-1, VCAM-1, iNOS, E-selectin, and p-p38MAPK, while promoting PKC and ERK1/2 phosphorylation in LPS-treated endothelial cells. These effects were abolished by a PKC inhibitor or α1-AR antagonist. PE also reduced p65 nuclear translocation, but this suppression is not blocked by PKC inhibition. Treatment with U0126 (a specific ERK1/2 inhibitor) reversed the effects of PE on p38MAPK phosphorylation. Our results demonstrate that cardiac endothelial α1-AR activation prevents sepsis-induced myocardial dysfunction in mice by inhibiting the endothelial injury via PKC-ERK/p38MAPK signaling pathway and a PKC-independent inhibition of p65 nuclear translocation. These findings offer a new perspective for septic patients with cardiac dysfunction by inhibiting cardiac endothelial cell injury through α1-AR activation.

Review of the therapeutic effects of traditional Chinese medicine in sepsis-associated encephalopathy

ETHNOPHARMACOLOGICAL RELEVANCE

Sepsis-associated encephalopathy (SAE) is a common and serious complication during the acute phase of and after recovery from sepsis that seriously affects the quality of life of patients. Traditional Chinese medicine (TCM) has been widely used in modern medicine for neurological anomalies and has become a therapeutic tool for the treatment of SAE due to its multitargeting effects and low toxicity and side effects.

AIMS OF THE STUDY

This review provides insights into the pathogenesis and treatments of SAE, focusing on the clinical and experimental impacts of TCM formulations and their single components.

METHODS

Several known databases such as PubMed, Web of Science, Google Scholar, China National Knowledge Infrastructure (CNKI), and others were extensively explored with keywords and phrases such as "sepsis-associated encephalopathy", "traditional Chinese medicine", "herbs", "SAE", "sepsis", "cerebral" or other relevant terms to obtain literature between 2018 and 2024.

RESULTS

Extensive evidence indicated that TCM could decrease mortality and normalize neurological function in patients with sepsis; these effects might be associated with factors such as reduced oxidative stress and downregulated expression of inflammatory factors.

CONCLUSIONS

TCM shows notable efficacy in treating SAE, warranting deeper mechanistic studies to optimize its clinical application.

Cardiovascular effects of Roflumilast during sepsis: Risks or benefits?

BACKGROUND

Phosphodiesterase-4 (PDE4) is responsible for terminating cyclic adenosine monophosphate (cAMP) signalling. PDE4 inhibitors, such as roflumilast (RFM), have anti-inflammatory activity and have been studied in inflammation-induced tissue damage in sepsis. However, the role of RFM on cardiovascular derangements induced by sepsis is still unknown. Thus, we aimed to evaluate the potential effects of RFM on cardiovascular collapse and multiorgan damage caused by sepsis.

METHODS

Sepsis was induced by cecal ligation and puncture (CLP) in male rats. Six hours after the CLP or sham procedure, animals were randomly assigned to receive either RFM (0.3 mg/kg) or vehicle subcutaneously, and cardiovascular parameters were assessed 24 h after the surgery and organ/plasma samples were collected for further analyses.

RESULTS

Sepsis induced hypotension, tachycardia, reduced renal blood flow (RBF) and hyporeactivity to vasoconstrictors both in vivo and ex vivo. RFM treatment increased systemic cAMP levels and RBF. RFM also attenuated hypoperfusion and liver damage induced by CLP. Furthermore, RFM reduced systemic nitric oxide (NO) levels in septic rats, while there were no changes in hepatic NOS-2 expression. Nevertheless, RFM exacerbated sepsis-induced hypotension and tachycardia without ameliorating vascular hyporeactivity.

CONCLUSION

Our data show that PDE-4 inhibition protects septic rats from hepatic injury and improves renal perfusion. However, RFM worsened hemodynamic parameters and showed no protection against sepsis-induced cardiovascular dysfunction and mortality. Thus, despite the anti-inflammatory benefits of RFM, its application in sepsis should be approached cautiously.

UFMylation is involved in serum inflammatory cytokines generation and splenic T cell activation induced by lipopolysaccharide

UFMylation, a novel ubiquitin-like protein modification system, has been recently found to be activated in inflammation. However, the effects of UFMylation activation on inflammation in vivo remains unclear. In the present study, we generated a UFMylation activated mice using transgenic (TG) techniques. Lipopolysaccharide (LPS) was used to induce systemic inflammation in both TG and non-transgenic (NTG) mice. Serum cytokines were detected using a Mouse Cytokine Array, and the proportions of splenic NK, B and T cells were determined by using flow cytometry. We found that TG mice showed increased serum G-CSF, TNF RII and decreased serum TCA-3, CD30L, bFGF, IL-15 and MIG compared with NTG mice at baseline. Furthermore, serum cytokines in TG mice exhibited different responses to LPS compared to NTG mice. LPS up-regulated serum TNF RII, G-CSF, MCP-5, RANTES, KC, BLC, MIG and down-regulated IL-1b, IL-2, IL-3, IL-4, IL-5, IL-7, IL-10, IL-12p40, IL-15, IL-17, IFN-γ, TCA-3, Eotaxin-2, LIX, MCP-1, TNFα, GM-CSF in NTG mice, whereas LPS up-regulated G-CSF, MCP-5, RANTES, KC, BLC, MIG, ICAM-1, PF4, Eotaxin, CD30L, MIP-1a, TNFRI and down-regulated IL-1b, IL-3, LIX, MCP-1, TNFα, GM-CSF in TG mice. Data from flow cytometry indicated that LPS significantly reduced the percentages of NK and NKT cells in NTG mice, whereas UFMylation activation inhibited LPS-induced NKT cell decrease. The proportions of B cells, total CD4+ and total CD8+ T cells were comparable between TG and NTG mice in response to LPS treatment, whereas the percentages of CD4+CD69+ and CD8+CD69+T cells were lower in TG mice. These findings suggest that UFMylation may alter LPS-induced serum cytokine profile and participate in splenic T cell activation in vivo.

A comparative study of a rapid phenotypic antimicrobial susceptibility testing system directly from positive blood cultures to the disk diffusion and VITEK 2 methods

BACKGROUND

Sepsis is a life-threatening condition that impacts 49 million people annually and causes 11 million deaths worldwide. Surviving bloodstream infections (BSIs) depends on the rapid administration of effective antimicrobial treatment, underscoring a need for rapid antimicrobial susceptibility testing (AST).

AIM

To evaluate the performance of Quantamatrix's dRAST v2.5 system (Seoul, South Korea) for AST directly from positive blood cultures as compared to the Disk-Diffusion (DD) and VITEK 2 methods.

METHODS

The study included 191 positive blood cultures from clinical samples and spiked blood culture bottles. Following Gram staining and species-level identification, AST was performed by VITEK 2 and standard DD methods using CLSI (2021) interpretation.

RESULTS

dRAST demonstrated very good AST performance for a Gram-negative isolate, and good performance for Gram-positive isolates, meeting CLSI criteria for the acceptance of a new method. Antimicrobials that were not considered verified compared to VITEK 2 and DD were cefazolin, ceftazidime, meropenem, and trimethoprim/sulfamethoxazole for Gram-negatives and clindamycin, erythromycin, penicillin, and oxacillin for Gram-positives. dRAST ESBL detection results were strongly correlated with the ESBL phenotypes obtained with other methods. Additional resistance mechanisms were in concordance with traditional tests.

CONCLUSIONS

dRAST demonstrated good AST performance, meeting CLSI criteria for most relevant antibiotics. dRAST was associated with a significant reduction in time-to-results, labor, and the subjectivity of result analyses, making it a valuable addition to efforts supporting the treatment of patients with bacteremia. AST (antimicrobial susceptibility test), blood culture, dRAST, rapid methods, sepsis, turnaround time (TAT).

Functional dependence following intensive care unit-treated sepsis: three-year follow-up results from the prospective Mid-German Sepsis Cohort (MSC)

Background

Surviving sepsis can lead to chronic physical, psychological and cognitive impairments, which affect millions of patients worldwide, including survivors after COVID-19 viral sepsis. We aimed to characterize the magnitude and trajectory of functional dependence and new impairments post-sepsis.

Methods

We conducted a prospective cohort study including sepsis survivors who had been discharged from five German intensive care units (ICUs), until 36 months post-discharge. Primary outcome was functional dependence, defined as ≥1 impaired activity of daily living (ADL; 10-item ADL score <100), self-reported nursing care dependence or nursing care level. Secondary outcome was post-sepsis morbidity in the physical, psychological or cognitive domain. We used a multistate, competing risk model to address competing events in the course of dependence, and conducted multiple linear regression analyses to identify predictors associated with the ADL score.

Findings

Of 3210 sepsis patients screened, 1968 survived the ICU treatment (61.3%). A total of 753 were included in the follow-up assessments of the Mid-German Sepsis cohort. Patients had a median age of 65 (Q1-Q3 56-74) years, 64.8% (488/753) were male and 76.1% (573/753) had a septic shock. Considering competing risk modelling, the probability of still being functional dependent was about 25%, while about 30% regained functional independence and 45% died within the three years post-sepsis. Patients reported a high burden of new and often overlapping impairments until three years post-sepsis. In the subgroup of three-year survivors (n = 330), new physical impairments affected 91.2% (n = 301) while new cognitive and psychological impairments were reported by 57.9% (n = 191) and 40.9% (n = 135), respectively. Patients with pre-existing functional limitations and higher age were at risk for low ADL scores three years after sepsis.

Interpretation

Sepsis survivorship was associated with a broad range of new impairments and led to functional dependence in around one quarter of patients. Targeted measures are needed to mitigate the burden of this Post-Sepsis-Syndrome and increase the proportion of patients that achieve functional improvements.

Funding

This work was supported by the Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC) at the Jena University Hospital funded by the German Ministry of Education and Research and by the Rudolf Presl GmbH & Co, Kreischa, Germany.

Global prevalence and characteristics of infections and clinical outcomes in hospitalised patients with cirrhosis: a prospective cohort study for the CLEARED Consortium

BACKGROUND

Infections have a poor prognosis in inpatients with cirrhosis. We aimed to determine regional variations in infections and their association with clinical outcomes in a global cohort of inpatients with cirrhosis.

METHODS

In this prospective cohort study initiated by the CLEARED Consortium, we enrolled adults (aged >18 years) with cirrhosis who were non-electively admitted to 98 hospitals from 26 countries or regions across six continents between Nov 5, 2021, and Dec 10, 2022. Data at admission, during hospitalisation, and for 30 days after discharge were collected through patient reports and chart reviews. Collected data included demographics; country and country income level per World Bank classifications (high-income countries [HICs], upper-middle-income countries [UMICs], and low-income or lower-middle-income countries [L-LMICs]); comorbidities; characteristics related to cirrhosis and the infections, including types, culture results, and drug resistance profile; antibiotic use; and disease course while hospitalised and for 30 days post-discharge. The primary outcome was in-hospital death or hospice referral in those with versus those without an admission infection (defined by the presence of infection on or within 48 h of admission). Multivariable log-binomial regression for in-hospital death or hospice referral was performed to identify risk factors.

FINDINGS

Of 4550 patients screened, 4238 patients (mean age 56·1 years [SD 13·3]; 2711 [64·0%] male and 1527 [36·0%] female) with complete data were enrolled. 1351 (31·9%) had admission infections. A higher proportion of patients in L-LMICs had infections (318 [41·7%] of 762 vs 444 [58·3%] without infection) than in UMICs (588 [30·6%] of 1922 vs 1334 [69·4%]) or HICs (445 [28·6%] of 1554 vs 1109 [71·4%]). Patients with admission infections had worse severity of cirrhosis and were more likely to have had an infection or been hospitalised in the preceding 6 months. The most common specific infection types were spontaneous bacterial peritonitis (391 [28·9%] of 1351), pneumonia (233 [17·2%]), and urinary tract infections (193 [14·3%]). 549 (40·6%) patients were culture-positive for bacterial or fungal infections, with the lowest culture-positive rates in Africa and mainland China. Most of the isolated organisms were Gram-negative (345 [63%] of 549), then Gram-positive (157 [29%]), and then fungi or mixed (47 [9%]), with Escherichia coli, Klebsiella pneumoniae, and Enterococcus spp being the top three isolated pathogens. The overall rate of drug resistance was 40% (220 of 549 with positive cultures), being highest in UMICs. The most used empirical antimicrobials were third-generation cephalosporins (453 [37%] of 1241), followed by the broad-spectrum β-lactams and β-lactamase inhibitors (289 [23%]). De-escalation was observed in 62 (20%) of 304 patients who had their antibiotics changed. Patients with versus without admission infections had a higher rate of in-hospital death or hospice transfer (299 [22·1%] of 1351 vs 232 [8·0%] of 2887; p<0·0001), a result replicated in multivariable analysis (adjusted risk ratio 1·75 [95% CI 1·42-2·06]; p<0·0001). Older age, self-reported female gender, not being in a HIC, lactulose use, and higher MELD-Na score were also associated with in-hospital death or hospice transfer on multivariable analysis.

INTERPRETATION

In the CLEARED Consortium cohort of inpatients with cirrhosis, the rates and types of infections, causative organisms, and culture-positivity varied substantially across regions, and infections were associated with a higher mortality risk. Culture positivity, which guides appropriate antibiotic use, was low. Taking a global perspective, considering regional variations in infections, drug resistance, and resources, could help to alleviate disparities in burden and outcomes.

FUNDING

US Department of Veterans Affairs, the Richmond Institute for Veterans Research, the National Natural Science Foundation of China, Shanghai Rising-Star Program, the National Council for Scientific and Technological Development of Brazil, and Shanghai Municipal Key Clinical Specialty.

Association of TLR4 polymorphisms (Asp299Gly and Thr399Ile) with sepsis: a meta-analysis and trial sequence analysis

Several investigations have been carried out to explore the genetic association of TLR4 codon variants, specifically Asp299Gly and Thr399Ile, and susceptibility to sepsis, but the results have been contradictory. The present study aimed to conduct a meta-analysis to draw a definitive conclusion regarding the role of TLR4 genetic variants (Asp299Gly and Thr399Ile) in sepsis. A thorough literature search was conducted using the PubMed, Scopus, and Science Direct databases. The inclusion and exclusion criteria were established to ensure the accuracy of the data. The Comprehensive Meta-Analysis Software v4 was utilized to perform the meta-analysis and related analyses. A total of 13 studies were analyzed, including 2328 sepsis cases and 2495 healthy controls for the TLR4 Asp299Gly variant. Eight studies provided genotype data for the rs4986791 polymorphism. The Asp299Gly variant showed a marginal protective effect in the allele (p = 0.08, odds ratio = 0.71) and dominant (p = 0.09, odds ratio = 0.71) genetic models, although it was not statistically significant. The trial sequential analysis indicated that further case-control studies are necessary to draw definitive conclusions about the TLR4 polymorphisms in sepsis. The TLR4 Asp299Gly variant may have a protective effect against sepsis. However, additional research with larger sample sizes across diverse populations is required to validate this finding.

Plasma MERTK is causally associated with infection mortality

BACKGROUND

Infectious diseases are a major cause of mortality in spite of existing public health, anti-microbial and vaccine interventions. We aimed to define plasma proteomic associates of infection mortality and then apply Mendelian randomisation (MR) to yield biomarkers that may be causally associated.

METHODS

We used UK Biobank plasma proteomic data to associate 2923 plasma proteins with infection mortality before 31st December 2019 (240 events in 52,520 participants). Since many plasma proteins also predict non-infection mortality, we focussed on those associated with >1.5-fold risk of infection mortality in an analysis excluding survivors. Protein quantitative trait scores (pQTS) were then used to identify whether genetically predicted protein levels also associated with infection mortality. To conduct Two Sample MR, we performed a genome-wide association study (GWAS) of infection mortality using UK Biobank participants without plasma proteomic data (n = 363,953 including 984 infection deaths).

FINDINGS

After adjusting for clinical risk factors, 1142 plasma proteins were associated with risk of infection mortality (false discovery rate <0.05). 259 proteins were associated with >1.5-fold increased risk of infection versus non-infection mortality. Of these, we identified genetically predicted increasing MERTK concentration was associated with increased risk of infection mortality. MR supported a causal association between increasing plasma MERTK protein and infection mortality (odds ratio 1.46 per unit; 95% CI 1.15- 1.85; p = 0.002).

CONCLUSION

Plasma MERTK is causally associated with infection mortality and warrants exploration as a potential therapeutic target.

Derivative spectrophotometry-assisted determination of tryptophan metabolites emerges host and intestinal flora dysregulations during sepsis

Sepsis is a life-threatening condition characterized by organ dysfunction resulting from a dysregulated host response to infection. Dysregulated tryptophan (TRP) metabolites serve as significant indicators for endogenous immune turnovers and abnormal metabolism in the intestinal microbiota during sepsis. Therefore, a high coverage determination of TRP and its metabolites in sepsis is beneficial for the diagnosis and prognosis of sepsis, as well as for understanding the underlying mechanism of sepsis development. However, similar structures in TRP metabolites make it challenging for separation and metabolite identification. Here, high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD) was developed to determine TRP metabolites in rat serum. The first-order derivative spectrophotometry of targeted metabolites in the serum was investigated and proved to be promising for chromatographic peak annotation across different columns and systems. The established method separating the targeted metabolites was optimized and validated to be sensitive and accurate. Application of the method revealed dysregulated TRP metabolites, associated with immune disorders and NAD + metabolism in both the host and gut flora in septic rats. Our findings indicate that the derivative spectrophotometry-assisted method enhances metabolite identifications for the chromatographic systems based on DAD detectors and holds promise for precision medicine in sepsis.

Inferior vena cava-aortic ratio measurement as a promising modality in assessing intravascular volume in children with sepsis

BACKGROUND

Hemodynamic monitoring is crucial for the comprehensive management of children with sepsis, particularly those involving the kidneys. Sepsis-associated acute kidney injury (S-AKI) is closely linked to poor outcomes. Recently, ultrasonography modalities have been widely accepted as a non-invasive, rapid, and reliable tool for assessing volume status. We conducted research to determine intravascular volume based on ultrasound examination in S-AKI patients.

METHODS

A prospective cohort study was conducted between December 2023 and March 2024 in the Pediatric Intensive Care Unit (PICU) at Hasan Sadikin General Hospital. We divided the patients into two groups: those with sepsis without AKI and those with S-AKI. The intravascular volume was measured by the IVC/Ao (inferior vena cava/abdominal aorta) ratio using two-dimensional ultrasonography and USCOM before and 24 h after fluid treatment. The results were analyzed using SPSS 25, with a significance level of p < 0.05.

RESULTS

A total of 36 pediatric patients (aged 1 month-18 years) with sepsis were included. The IVC/Ao ratio before and after the fluid intervention demonstrated significant differences between the two groups (p < 0.001). USCOM Cardiac Index (CI) before and after the intervention also showed significant differences between the two groups (p < 0.001). Patients with S-AKI exhibited a poor hemodynamic response in the IVC/Ao ratio two-dimensional ultrasonography and USCOM examination.

CONCLUSIONS

IVC/Ao ratio measurement is as accurate as USCOM and can be used as a simple and cost-effective alternative for hemodynamic monitoring.

Quercetin protects against sepsis-associated encephalopathy by inhibiting microglia-neuron crosstalk via the CXCL2/CXCR2 signaling pathway

BACKGROUND

Sepsis-associated encephalopathy (SAE) is a common brain lesion associated with severe sepsis, for which ferroptosis is a key driving factor. Thus, suppressing ferroptosis may be an effective strategy for treating SAE. Quercetin (QUE) is a natural flavonoid with antioxidant and anti-inflammatory properties. However, its role on ferroptosis in SAE remains unclear.

PURPOSE

This study aimed to investigate the mechanism underlying the therapeutic effect of QUE on cecal ligation perforation (CLP)-induced SAE.

METHODS

In vivo and in vitro SAE models were established using CLP and lipopolysaccharide (LPS), respectively. Both models underwent pre-treatment with QUE.

RESULTS

QUE attenuated CLP-induced symptoms, including temperature changes, neurological severity scores, learning and memory dysfunction, inflammatory cytokine release, and microglia activation in SAE mice, and inhibited LPS-induced microglia recruitment and chemotaxis. Bioinformatics analysis revealed that the C-X-C motif chemokine ligand 2 (CXCL2)/C-X-C motif chemokine receptor 2 (CXCR2) axis may play a key role in QUE-mediated protection against SAE. Moreover, QUE significantly inhibited LPS-induced CXCL2 up-regulation and protein secretion from microglia. Recombinant mouse-derived CXCL2 (rmCXCL2) promoted inflammatory cytokine secretion, NF-κB/NLRP3 signaling activation, and microglia recruitment and chemotaxis. Furthermore, rmCXCL2 induced ferroptosis in mouse hippocampal neurons, as evidenced by elevated malondialdehyde levels, decreased glutathione levels, excessive iron uptake, and altered ferroptosis-related protein expression. The CXCR2 antagonist SB225002 effectively reversed the effects of rmCXCL2. Importantly, in vivo experiments further demonstrated that the therapeutic effect of QUE on SAE was inhibited by rmCXCL2.

CONCLUSION

This study demonstrates that CXCL2 secreted by activated microglia mediates microglia self-activation and induces hippocampal neuronal ferroptosis via CXCR2 and that QUE exerts neuroprotective effects on SAE by blocking interactions between microglia and neurons via CXCL2/CXCR2 pathway inhibition.

Prognostic accuracy of SOFA, MEWS, and SIRS criteria in predicting the mortality rate of patients with sepsis: A meta-analysis

BACKGROUND

In recent years, some studies classified patients with sepsis and predicted their mortality by using some evaluation scales. Several studies reported significant differences in the predictive values of several tools, and the non-uniformity of the cut-off value.

AIM

To determine and compare the prognostic accuracy of Sequential Organ Failure Assessment (SOFA) score, Modified Early Warning Score (MEWS), and Systemic Inflammatory Response Syndrome (SIRS) criteria in predicting the mortality of patients with sepsis.

METHODS

This study comprised of systematic literature review and meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. We searched PubMed, Embase, Web of Science and Cochrane Library databases from their establishment to July 31, 2022. The research articles published in the index journals provide sufficient data (true positive, false positive, true negative, and false negative results) for patients with sepsis. The combined sensitivity and specificity of the 95% confidence interval (CI) were calculated using the bivariate random effect model (BRM). The hierarchical overall subject working characteristics (HSROC) curve was drawn to evaluate the accuracy of the overall prognosis.

RESULTS

Data of 55 088 patients from 32 studies were included in this meta-analysis. SOFA had an intermediate sensitivity of 0.73 (95% CI: 0.67-0.78) and a specificity of 0.70 (0.63-0.76). SIRS criteria had the highest sensitivity of 0.75 (0.66-0.82) and the lowest specificity of 0.40 (0.29-0.52). MEWS had the lowest sensitivity of 0.49 (0.40-0.59) and the highest specificity of 0.82 (0.78-0.86).

CONCLUSIONS

Among SOFA, MEWS, and SIRS criteria, SOFA showed moderate sensitivity and specificity for predicting mortality in patients with sepsis, the highest sensitivity of SIRS and the strongest specificity of MEWS for predicting mortality in patients with sepsis. The future research direction is to combine the relevant indicators of MEWS and SIRS to develop a measurement tool with high reliability and validity.

RELEVANCE TO CLINICAL PRACTICE

The review provides useful insights into the prognostic accuracy of different assessment tools in predicting mortality in sepsis patients, which will help clinicians choose the most appropriate tool for early identification and treatment of sepsis. The findings may also contribute to the development of more accurate and reliable prognostic models for sepsis.

Moderate IV Fluid Resuscitation Is Associated With Decreased Sepsis Mortality

OBJECTIVES

Significant practice variation exists in the amount of resuscitative IV fluid given to patients with sepsis. Current research suggests equipoise between a tightly restrictive or more liberal strategy but data is lacking on a wider range of resuscitation practices. We sought to examine the relationship between a wide range of fluid resuscitation practices and sepsis mortality and then identify the primary driver of this practice variation.

DESIGN

Retrospective analysis of the Premier Healthcare Database.

SETTING

Six hundred twelve U.S. hospitals.

PATIENTS

Patients with sepsis and septic shock admitted from the emergency department to the ICU from January 1, 2016, to December 31, 2019.

INTERVENTIONS

The volume of resuscitative IV fluid administered before the end of hospital day- 1 and mortality.

MEASUREMENTS AND MAIN RESULTS

In total, 190,682 patients with sepsis and septic shock were included in the analysis. Based upon patient characteristics and illness severity, we predicted that physicians should prescribe patients with sepsis a narrow mean range of IV fluid (95% range, 3.6-4.5 L). Instead, we observed wide variation in the mean IV fluids administered (95% range, 1.7-7.4 L). After splitting the patients into five groups based upon attending physician practice, we observed patients in the moderate group (4.0 L; interquartile range [IQR], 2.4-5.1 L) experienced a 2.5% reduction in risk-adjusted mortality compared with either the very low (1.6 L; IQR, 1.0-2.5 L) or very high (6.1 L; IQR, 4.0-9.0 L) fluid groups p < 0.01). An analysis of within- and between-hospital IV fluid resuscitation practices showed that physician variation within hospitals instead of practice differences between hospitals accounts for the observed variation.

CONCLUSIONS

Individual physician practice drives excess variation in the amount of IV fluid given to patients with sepsis. A moderate approach to IV fluid resuscitation is associated with decreased sepsis mortality and should be tested in future randomized controlled trials.

iRhom2 deficiency reduces sepsis-induced mortality associated with the attenuation of lung macrophages in mice

Sepsis has a high mortality rate and leads to multi-organ failure, including lung injury. Inactive rhomboid protease family protein (iRhom2) has been identified as accountable for the release of TNF-α, a crucial mediator in the development of sepsis. This study aimed to evaluate the role of iRhom2 in sepsis and sepsis-induced acute lung injury (ALI). TNF-α and IL-6 secretion in vitro by peritoneal macrophages from wild-type (WT) and iRhom2 knoukout (KO) mice was assessed by enzyme-linked immunosorbent assay. Cecal ligation and puncture (CLP)-induced murine sepsis model was used for in vivo experiments. To evaluate the role of iRhom2 deficiency on survival during sepsis, both WT and iRhom2 KO mice were monitored for 8 consecutive days following the CLP. For histologic and biochemical examination, the mice were killed 18 h after CLP. iRhom2 deficiency improved the survival of mice after CLP. iRhom2 deficiency decreased CD68+ macrophage infiltration in lung tissues. Multiplex immunohistochemistry revealed that the proportion of Ki-67+ CD68+ macrophages was significantly lower in iRhom2 KO mice than that in WT mice after CLP. Moreover, CLP-induced release of TNF-α and IL-6 in the serum were significantly inhibited by iRhom2 deficiency. iRhom2 deficiency reduced NF-kB p65 and IκBα phosphorylation after CLP. iRhom2 deficiency reduces sepsis-related mortality associated with attenuated macrophage infiltration and proliferation in early lung injury. iRhom2 may play a pivotal role in the pathogenesis of sepsis and early stage of sepsis-induced ALI. Thus, iRhom2 may be a potential therapeutic target for the management of sepsis and sepsis-induced ALI.

Co-Delivery of Renal Clearable Cerium Complex and Synergistic Antioxidant Iron Complex for Treating Sepsis

The mononuclear phagocytic system clears the circulating inorganic nanomaterials from the bloodstream, which raises concerns about the chronic toxicity of the accumulated metal species. A better understanding of the behavior of each metal after systemic injection is thus required for clinical translations. This study investigates the significance of the metal-ligand interaction on the accumulation of cerium and demonstrates that only the form in which cerium is coordinated to a multidentate chelator with a strong binding affinity does not accumulate in major organs. Specifically, cerium complexed with diethylenetriamine pentaacetic acid (DTPA) forms renally excretable nanoparticles in vivo to circumvent the leaching of cerium ions, whereas weakly coordinated cerium-based nanomaterials produce insoluble precipitates upon encountering physiological phosphate anions. Ceria-based renally clearable nanoparticles (CRNs) derived from cerium-DTPA are utilized as the antioxidant pair with iron-DTPA, in which their combination leverages the Fenton reaction to synergistically scavenge hydrogen peroxide. This reduces the gene expression of pro-inflammatory factors in the macrophages activated with lipopolysaccharide as well as improves the survival rate of septic mice by alleviating the systemic inflammatory response and its downstream tissue injury in the liver, spleen, and kidneys. This study demonstrates that CRNs combined with iron-DTPA can be utilized as nonaccumulative nanomedicines for treating systemic inflammation, thereby overcoming the limitations of conventional ceria nanoparticle-based treatments.

Mechanism of lactic acidemia-promoted pulmonary endothelial cells death in sepsis: role for CIRP-ZBP1-PANoptosis pathway

BACKGROUND

Sepsis is often accompanied by lactic acidemia and acute lung injury (ALI). Clinical studies have established that high serum lactate levels are associated with increased mortality rates in septic patients. We further observed a significant correlation between the levels of cold-inducible RNA-binding protein (CIRP) in plasma and bronchoalveolar lavage fluid (BALF), as well as lactate levels, and the severity of post-sepsis ALI. The underlying mechanism, however, remains elusive.

METHODS

C57BL/6 wild type (WT), Casp8-/-, Ripk3-/-, and Zbp1-/- mice were subjected to the cecal ligation and puncture (CLP) sepsis model. In this model, we measured intra-macrophage CIRP lactylation and the subsequent release of CIRP. We also tracked the internalization of extracellular CIRP (eCIRP) in pulmonary vascular endothelial cells (PVECs) and its interaction with Z-DNA binding protein 1 (ZBP1). Furthermore, we monitored changes in ZBP1 levels in PVECs and the consequent activation of cell death pathways.

RESULTS

In the current study, we demonstrate that lactate, accumulating during sepsis, promotes the lactylation of CIRP in macrophages, leading to the release of CIRP. Once eCIRP is internalized by PVEC through a Toll-like receptor 4 (TLR4)-mediated endocytosis pathway, it competitively binds to ZBP1 and effectively blocks the interaction between ZBP1 and tripartite motif containing 32 (TRIM32), an E3 ubiquitin ligase targeting ZBP1 for proteasomal degradation. This interference mechanism stabilizes ZBP1, thereby enhancing ZBP1-receptor-interacting protein kinase 3 (RIPK3)-dependent PVEC PANoptosis, a form of cell death involving the simultaneous activation of multiple cell death pathways, thereby exacerbating ALI.

CONCLUSIONS

These findings unveil a novel pathway by which lactic acidemia promotes macrophage-derived eCIRP release, which, in turn, mediates ZBP1-dependent PVEC PANoptosis in sepsis-induced ALI. This finding offers new insights into the molecular mechanisms driving sepsis-related pulmonary complications and provides potential new therapeutic strategies.

Sepsis-induced changes in pyruvate metabolism: insights and potential therapeutic approaches

Sepsis is a heterogeneous syndrome resulting from a dysregulated host response to infection. It is considered as a global major health priority. Sepsis is characterized by significant metabolic perturbations, leading to increased circulating metabolites such as lactate. In mammals, pyruvate is the primary substrate for lactate production. It plays a critical role in metabolism by linking glycolysis, where it is produced, with the mitochondrial oxidative phosphorylation pathway, where it is oxidized. Here, we provide an overview of all cytosolic and mitochondrial enzymes involved in pyruvate metabolism and how their activities are disrupted in sepsis. Based on the available data, we also discuss potential therapeutic strategies targeting these pyruvate-related enzymes leading to enhanced survival.

Enhancing insight into ferroptosis mechanisms in sepsis: A genomic and pharmacological approach integrating single-cell sequencing and Mendelian randomization

This research investigated the intricate relationship between ferroptosis and sepsis by utilizing advanced genomic and pharmacological methodologies. Specifically, we obtained expression quantitative trait loci (eQTLs) for 435 genes associated with ferroptosis from the eQTLGen Consortium and detected notable cis-eQTLs for 281 of these genes. Next, we conducted a detailed analysis to assess the impact of these eQTLs on susceptibility to sepsis using Mendelian randomization (MR) with data from a cohort of 10,154 sepsis patients and 452,764 controls sourced from the UK Biobank. MR analysis revealed 16 ferroptosis-related genes that exhibited significant associations with sepsis outcomes. To bolster the robustness of these findings, sensitivity analyses were performed to assess pleiotropy and heterogeneity, thus confirming the reliability of the causal inferences. Furthermore, single-cell RNA sequencing data from sepsis patients offered a detailed examination of gene expression profiles, demonstrating varying levels of ferroptosis marker expression across different cell types. Pathway enrichment analysis utilizing gene set enrichment analysis (GSEA) further revealed the key biological pathways involved in the progression of sepsis. Additionally, the use of computational molecular docking facilitated the prediction of interactions between identified genes and potential therapeutic compounds, highlighting novel drug targets. In conclusion, our integrated approach combining genomics and pharmacology offers valuable insights into the involvement of ferroptosis in sepsis, laying the groundwork for potential therapeutic strategies targeting this cell death pathway to enhance sepsis management.

Forsythiaside A alleviates acute lung injury via the RNF99/TRAF6/NF-κB signaling pathway

The aim of this study was to investigated the effects of forsythiaside A (FA) on acute lung injury (ALI). The lung tissue pathological was detected by hematoxylin-eosin staining (HE) staining. Wet weight/dry weight (w/d) of the lung in mice was measured. Cytokine such as interleukin 1β (IL-1β), IL-6 and tumor necrosis factor-α (TNF-α) were also detected. Compared with the vector group, the protein expression levels of TRAF6 and TAK1 the RNF99 group were significantly reduced. Ubiquitinated TRAF6 protein was increased after knockdown of RNF99. Finally, it was found that FA significantly ameliorated ALI via regulation of RNF99/TRAF6/NF-κB signal pathway. In conclusion, RNF99 was an important biomarker in ALI and FA alleviated ALI via RNF99/ TRAF6/NF-κB signal pathway.

CMTM3 regulates neutrophil activation and aggravates sepsis through TLR4 signaling

Regulation of neutrophil activation plays a significant role in managing sepsis. CKLF-like MARVEL transmembrane domain containing (CMTM)3 is a membrane protein involved in immune response. Here, we find that CMTM3 expression is elevated in sepsis and plays a crucial role in mediating the imbalance of neutrophil migration. Cmtm3 knockout improves the survival rate of septic mice, mitigate inflammatory responses, and ameliorate organ damage. Mechanistically, the deletion of Cmtm3 reduced the expression of Toll-like receptor 4 (TLR4) on neutrophils, leading to a decrease in the expression of C-X-C motif chemokine receptor 2 (CXCR2) on the cell membrane. This resulted in a reduced migration of neutrophils from the bone marrow to the bloodstream, thereby attenuating their recruitment to vital organs. Our findings suggest that targeting CMTM3 holds promise as a therapeutic approach to ameliorate the dysregulation of neutrophil migration and multi-organ damage associated with sepsis.

Unfractionated Heparin Enhances Sepsis Prognosis Through Inhibiting Drp1-Mediated Mitochondrial Quality Imbalance

Unfractionated heparin (UFH) is commonly used as an anticoagulant in sepsis treatment and has recently been found to have non-anticoagulant effects, but underlying mechanisms remain unclear. This retrospective clinical data showed that UFH has significant protective effects in sepsis compared to low-molecular-weight heparin and enoxaparin, indicating potential benefits of its non-anticoagulant properties. Recombinant protein chip screening, surface plasmon resonance, and molecular docking data demonstrated that UFH specifically bound to the cytoplasmic Drp1 protein through its zone 2 non-anticoagulant segment. In-vitro experiments verified that UFH's specific binding to Drp1 suppressed Drp1 translocation to mitochondria following "sepsis" challenge, thereby improving mitochondrial morphology, function and metabolism in vascular endothelial cells. Consequently, UHF comprehensively protected mitochondrial quality, thus reducing vascular leakage and improving prognosis in a sepsis rat model. These findings highlight the potential of UFH as a sepsis treatment strategy targeting non-anticoagulation mechanism.

Association between acetaminophen and risk of mortality in patients with sepsis-associated acute kidney injury: A retrospective cohort study from the MIMIC-IV database

The occurrence of sepsis-associated acute kidney injury (SA-AKI) predicts a worse prognosis. We aimed to assess the impact of acetaminophen use on short-term mortality in patients with SA-AKI. A total of 6563 patients diagnosed with SA-AKI from the 2008 to 2019 Medical Information Mart for Intensive Care IV (MIMIC-IV) database were enrolled in this retrospective cohort study. The Cox regression model was utilized to analyze the associations of acetaminophen with 30-day mortality and in-hospital mortality. Additional propensity score matching (PSM) analysis was performed regarding patients with acetaminophen use versus those without. Of these patients, 30-day mortality occurred in 1421 (21.65%) patients and in-hospital mortality in 1246 (18.99%) patients. Patients who used acetaminophen were associated with a reduced risk of 30-day mortality (hazard ratio (HR) = 0.80, 95% confidence interval (CI): 0.71-0.90) and in-hospital mortality (HR = 0.72, 95% CI: 0.63-0.82). The PSM analysis demonstrated that acetaminophen use was still related to a reduced risk of 30-day mortality and in-hospital mortality. Subgroup analysis showed that the relationships between acetaminophen and 30-day mortality and in-hospital mortality were consistent across subgroups (p < 0.05). The use of acetaminophen has an association with lower short-term mortality in patients with SA-AKI.

Secondhand smoking increased the possibility of hypertension with a significant time and frequency dose-response relationship

In this research, we investigated whether secondhand smoking (SHS) increases the possibility of hypertension. We used data from the Shaanxi baseline survey of the Regional Ethnic Cohort Study in Northwest China (RECS). Active smoking and SHS were determined by questionnaires. Hypertension was defined as self-reported or objectively measured. Multivariable logistic regression model was performed to estimate the risk of hypertension under active smoking and SHS. Compared to never-smokers, exposure to SHS had a 9% (P = 0.005) higher possibility of hypertension. The adjusted OR for exposure time of ≤ 3 h/week, 3-12 h/week, and > 12 h/week were 1.03 (P = 0.545), 1.10 ( P = 0.040), and 1.15 (P = 0.015), respectively. The adjusted OR for frequency of SHS of 1-2 times/week, 3-5 times/week, and nearly every day were 0.94 (P = 0.421), 1.01 (P = 0.846), and 1.14 (P < 0.001), respectively. Compared to smokers, additional exposure to SHS had a more than threefold increased possibility of having hypertension. The adjusted OR for hypertension was 1.07 (P = 0.254), and 1.23 (P = 0.007) in only smokers and smokers with SHS, respectively. Our study provided evidence that SHS could be a risk factor for hypertension, and additional exposure of active smokers to SHS significantly increases the possibility of hypertension. Reducing the frequency or time of SHS may be effective in preventing hypertension.

Deleting fibroblast growth factor 2 in macrophages aggravates septic acute lung injury by increasing M1 polarization and inflammatory cytokine secretion

Septic lung injury is strongly associated with polarization of M1 macrophages and excessive cytokine release. Fibroblast growth factor (FGF) signaling plays a role in both processes. However, the impact of FGF2 deficiency on macrophage polarization and septic acute lung injury remains unclear. To investigate this, we obtained macrophages from FGF2 knockout mice and examined their polarization and inflammatory cytokine expression. We also eliminated endogenous macrophages using clodronate liposomes and administered FGF2 knockout or WT macrophages intravenously in conjunction with cecal ligation and puncture (CLP) surgery to induce sepsis. In vitro analysis by flow cytometry and real-time PCR analysis demonstrated that FGF2 deficiency resulted in increased expression of M1 markers (iNOS and CD86) and inflammatory cytokines (CXCL1, IL1β, and IL6), especially after LPS stimulation. Additionally, immunofluorescence demonstrated increased nuclear translocation of p65 NF-κB in FGF2 knockout macrophages and RNA-seq analysis showed enrichment of differentially expressed genes in the IL17 and TNFα inflammatory signaling pathways. Furthermore, in vivo experiments revealed that depletion of FGF2 in macrophages worsened sepsis-induced lung inflammation, lung vascular leak, and lung histological injury, accompanied by an increase in CD86-positive cells and apoptosis. Our study suggests that FGF2 deficiency in macrophages plays a critical role in the pathogenesis of septic ALI, possibly because of the enhanced M1 macrophage polarization and production of proinflammatory cytokines. These findings provide empirical evidence for potential therapeutic interventions targeting FGF2 signaling to modulate the polarization of M1 and M2 macrophages in the management of sepsis-induced acute lung injury.

Neutrophil Hitchhiking Enhances Liposomal Dexamethasone Therapy of Sepsis

Sepsis is characterized by a dysregulated immune response and is very difficult to treat. In the cecal ligation and puncture (CLP) mouse model, we show that nanomedicines can effectively alleviate systemic and local septic events by targeting neutrophils. Specifically, by decorating the surface of clinical-stage dexamethasone liposomes with cyclic arginine-glycine-aspartic acid (cRGD) peptides, we promote their engagement with neutrophils in the systemic circulation, leading to their prominent accumulation at primary and secondary sepsis sites. cRGD-targeted dexamethasone liposomes potently reduce immature circulating neutrophils and neutrophil extracellular traps in intestinal sepsis induction sites and the liver. Additionally, they mitigate inflammatory cytokines systemically and locally while preserving systemic IL-10 levels, contributing to lower IFN-γ/IL-10 ratios as compared to control liposomes and free dexamethasone. Our strategy addresses sepsis at the cellular level, illustrating the use of neutrophils both as a therapeutic target and as a chariot for drug delivery.

Screening of hub genes for sepsis-induced myopathy by weighted gene co-expression network analysis and protein-protein interaction network construction

Sepsis-induced myopathy is one of the serious complications of sepsis, which severely affects the respiratory and peripheral motor systems of patients, reduces their quality of life, and jeopardizes their lives, as evidenced by muscle atrophy, loss of strength, and impaired regeneration after injury. The pathogenesis of sepsis-induced myopathy is complex, mainly including cytokine action, enhances free radical production in muscle, increases muscle protein hydrolysis, and decreases skeletal muscle protein synthesis, etc. The above mechanisms have been demonstrated in existing studies. However, it is still unclear how the overall pattern of gene co-expression affects the pathological process of sepsis-induced myopathy. Therefore, we intend to identify hub genes and signaling pathways. Weighted gene co-expression network analysis was our main approach to study gene expression profiles: skeletal muscle transcriptome in ICU patients with sepsis-induced multi-organ failure (GSE13205). After data pre-processing, about 15,181 genes were used to identify 13 co-expression modules. Then, 16 genes (FEM1B, KLHDC3, GPX3, NIFK, GNL2, EBNA1BP2, PES1, FBP2, PFKP, BYSL, HEATR1, WDR75, TBL3, and WDR43) were selected as the hub genes including 3 up-regulated genes and 13 down-regulated genes. Then, Gene Set Enrichment Analysis was performed to show that the hub genes were closely associated with skeletal muscle dysfunction, necrotic and apoptotic skeletal myoblasts, and apoptosis in sepsis-induced myopathy. Overall, 16 candidate biomarkers were certified as reliable features for more in-depth exploration of sepsis-induced myopathy in basic and clinical studies.

The Universal Vital Assessment (UVA) score at 6 hours post-resuscitation predicts mortality in hospitalized adults with severe sepsis in Mbarara, Uganda

Sepsis is the leading cause of global death with the highest burden found in sub-Saharan Africa (sSA). The Universal Vital Assessment (UVA) score is a validated resource-appropriate clinical tool to identify hospitalized patients in sSA who are at risk of in-hospital mortality. Whether a decrease in the UVA score over 6 hours of resuscitation from sepsis is associated with improved outcomes is unknown. We aimed to determine (1) the association between 6-hour UVA score and in-hospital mortality, and (2) if a decrease in UVA score from admission to 6 hours was associated with improved in-hospital mortality. We analyzed data from participants with severe sepsis aged ≥14 years enrolled at the Mbarara Regional Referral Hospital in Uganda from October 2014 through May 2015. Among 197 participants, the median (interquartile range) age was 34 (27-47) years, 99 (50%) were female and 116 (59%) were living with HIV. At 6 hours, of the 65 participants in the high-risk group, 28 (43%) died compared to 28 (30%) of 94 in the medium-risk group (odds ratio [OR] 0.56, 95% confidence interval [CI] 0.29,1.08, p = 0.086) and 3 (9%) of 33 in the low-risk group (OR 0.13, 95% CI 0.03, 0.42, p = 0.002). In a univariate analysis of the 85 participants who improved their UVA risk group at 6 hours, 20 (23%) died compared to 39 (36%) of 107 participants who did not improve (OR 0.54, 95% CI 0.27-1.06, p = 0.055). In the multivariable analysis, the UVA score at 6 hours (adjusted OR [aOR] 1.26, 95%CI 1.10-1.45, p<0.001) was associated with in-hospital mortality. When adjusted for age and sex, improvement in the UVA risk group over 6 hours was associated with a non-statistically significant 43% decrease in odds of mortality (aOR 0.57, 95%CI 0.29-1.07, p = 0.08). Targeting a decrease in UVA score over 6 hours from admission may be a useful clinical endpoint for sepsis resuscitation in sSA, but this would need to be proven in a clinical trial.

High-cost users after sepsis: a population-based observational cohort study

BACKGROUND

High-cost users (HCU) represent important targets for health policy interventions. Sepsis is a life-threatening syndrome that is associated with high morbidity, mortality, and economic costs to the healthcare system. We sought to estimate the effect of sepsis on being a subsequent HCU.

METHODS

Using linked health-administrative databases, we conducted a population-based, propensity score-weighted cohort study of adults who survived a hospitalization in Ontario, Canada between January 2016 and December 2017. Sepsis was identified using a validated algorithm. The primary outcome was being a persistent HCU after hospital discharge (in the top 5% or 1% of total health care spending for 90 consecutive days), and the proportion of follow-up time since discharge as a HCU.

RESULTS

We identified 927,057 hospitalized individuals, of whom 79,065 had sepsis. Individuals who had sepsis were more likely to be a top 5% HCU for 90 consecutive days at any time after discharge compared to those without sepsis (OR 2.24; 95% confidence interval [CI] 2.04-2.46) and spent on average 42.3% of their follow up time as a top 5% HCU compared to 28.9% of time among those without sepsis (RR 1.46; 95% CI 1.45-1.48). Individuals with sepsis were more likely to be a top 1% HCU for 90 consecutive days compared to those without sepsis (10% versus 5.1%, OR 2.05 [95% CI 1.99-2.11]), and spent more time as a top 1% HCU (18.5% of time versus 10.8% of time, RR 1.68 [95% CI 1.65-1.70]).

CONCLUSIONS

The sequelae of sepsis result in higher healthcare costs with important economic implications. After discharge, individuals who experienced sepsis are more likely to be a HCU and spend more time as a HCU compared to individuals who did not experience sepsis during hospitalization.

Senolytics To slOw Progression of Sepsis (STOP-Sepsis) in elderly patients: Study protocol for a multicenter, randomized, adaptive allocation clinical trial

BACKGROUND

Senescent immune cells exhibit altered gene expression and resistance to apoptosis. The prevalence of these cells increases with age and emerging data implicate senescence-associated maladaptive signaling as a potential contributor to sepsis and septic shock. The senolytic drug fisetin promotes clearance of senescent cells and is hypothesized to mitigate septic responses to infection.

METHODS

We are conducting a multi-center, randomized, double-blinded, adaptive allocation phase 2 clinical trial to assess the efficacy of the senolytic drug fisetin in preventing clinical deterioration of elderly patients diagnosed with sepsis. We intend to enroll and randomize 220 elderly patients (age > 65) with the clinical diagnosis of sepsis to receive either fisetin as a single oral dose of 20 mg/kg, fisetin in two oral doses of 20 mg/kg each spaced 1 day apart, or placebo. The primary outcome will be changed in the composite of cardiovascular, respiratory, and renal sequential organ failure assessment scores at 7 days from enrollment. Secondary outcomes include quantification of senescent CD3 + cells at 7 days, and 28-day assessments of organ failure-free days, days in an intensive care unit, and all-cause mortality.

DISCUSSION

This multi-center, randomized, double-blinded trial will assess the efficacy of fisetin in preventing clinical deterioration in elderly patients with sepsis and measure the effects of this drug on the prevalence of senescent immune cells. We intend that the results of this phase 2 trial will inform the design of a larger phase 3 study.

TRIAL REGISTRATION

This trial is registered to ClinicalTrials.gov under identifier NCT05758246, first posted on March 7, 2023.

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.