Sepsis-related mortality in China: a descriptive analysis

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.

The Impact of Delayed Transition From Noninvasive to Invasive Mechanical Ventilation on Hospital Mortality in Immunocompromised Patients With Sepsis

OBJECTIVE

To determine whether mortality differed between initial invasive mechanical ventilation (IMV) or noninvasive ventilation (NIV) followed by delayed IMV in immunocompromised patients with sepsis.

DESIGN

Retrospective analysis using the National Data Center for Medical Service claims data in China from 2017 to 2019.

SETTING

A total of 3530 hospitals across China.

PATIENTS

A total of 36,187 adult immunocompromised patients with sepsis requiring ventilation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was hospital mortality. Patients were categorized into NIV initiation or IMV initiation groups based on first ventilation. NIV patients were further divided by time to IMV transition: no transition, immediate (≤ 1 d), early (2-3 d), delayed (4-7 d), or late (≥ 8 d). Mortality was compared between groups using weighted Cox models. Over the median 9-day follow-up, mortality was similar for initial NIV versus IMV (adjusted hazard ratio [HR] 1.006; 95% CI, 0.959-1.055). However, among NIV patients, a longer time to IMV transition is associated with stepwise increases in mortality, from immediate transition (HR 1.65) to late transition (HR 2.51), compared with initial IMV. This dose-response relationship persisted across subgroups and sensitivity analyses.

CONCLUSIONS

Prolonged NIV trial before delayed IMV transition is associated with higher mortality in immunocompromised sepsis patients ultimately intubated.

Association between lactate to hematocrit ratio and 30-day all-cause mortality in patients with sepsis: a retrospective analysis of the Medical Information Mart for Intensive Care IV database

Background

The lactate to hematocrit ratio (LHR) has not been assessed for predicting all-cause death in sepsis patients. This study aims to evaluate the relationship between LHR and 30-day all-cause mortality in sepsis patients.

Methods

This retrospective study used the data from Medical information mart for intensive care IV (MIMIC-IV, version 2.0). Our study focused on adult sepsis patients who were initially hospitalized in the Intensive care unit (ICU). The prognostic significance of admission LHR for 30-day all-cause mortality was evaluated using a multivariate Cox regression model, ROC curve analysis, Kaplan-Meier curves, and subgroup analyses.

Results

A total of 3,829 sepsis patients participated in this study. Among the cohort, 8.5% of individuals died within of 30 days (p < 0.001). The area under the curve (AUC) for LHR was 74.50% (95% CI: 71.6-77.50%), higher than arterial blood lactate (AUC = 71.30%), hematocrit (AUC = 64.80%), and shows no significant disadvantage compared to qSOFA, SOFA, and SAPS II. We further evaluated combining LHR with qSOFA score to predict mortality in sepsis patients, which shows more clinical significance. ROC curve analysis showed that 6.538 was the optimal cutoff value for survival and non-survival groups. With LHR ≥6.538 vs. LHR <6.538 (p < 0.001). Subgroup analysis showed significant interactions between LHR, age, sex, and simultaneous acute respiratory failure (p = 0.001-0.005).

Conclusion

LHR is an independent predictor of all-cause mortality in sepsis patients after admission, with superior predictive ability compared to blood lactate or hematocrit alone.

CTLA-4 expression on CD4+ lymphocytes in patients with sepsis-associated immunosuppression and its relationship to mTOR mediated autophagic-lysosomal disorder

Background

The aim of this study was to clarify the relationship between expression level of CTLA-4 on CD4+ T cells and sepsis-associated immunosuppression (SAI), and to elucidate the possible mechanism of mTOR pathway mediated autophagic-lysosomal disorder in regulating CTLA-4 expression.

Methods

We enrolled 63 sepsis patients admitted to our ICU between January 1 and June 30, 2023. Peripheral blood mononuclear cells were isolated from the patients within 24 hours of recruitment. Expression levels of mTOR, P62, LC3II, and CTLA-4 on circulating CD4+ T lymphocytes were quantitated using flow cytometry. The association of these markers and relationship between CTLA-4 expression and the incidence of SAI and 28-day mortality were comprehensively analyzed.

Results

Compared with non-immunosuppressed patients with sepsis, patients with SAI had a higher 28-day mortality rate (37.5% vs 13.0%, P=0.039) and higher CTLA-4 mean fluorescence intensity (MFI) on CD4+ T cells (328.7 versus 78.7, P<0.0001). CTLA-4 MFI on CD4+ cells was independently associated with the occurrence of SAI (95% confidence interval: 1.00-1.14, P=0.044). In patients with sepsis and SAI, non-survivors had higher CTLA-4 expression than survivors (sepsis: 427.5 versus 130.6, P=0.002; and SAI: 506.7 versus 225.2, P<0.0001). The sensitivity and specificity of CTLA-4 MFI at predicting 28-day mortality in patients with SAI was 100% and 80% respectively with the cutoff value of 328.7 and the area under the curve of 0.949. The MFI of mTOR, P62, and LC3II on CD4+ T cells were statistically higher in patients with SAI than in non-immunosuppressed patients (267.2 versus 115.9, P<0.0001; 314.8 versus 173.7, P<0.0001; and 184.7 versus 1123.5, P=0.012, respectively); P62 and LC3II were markedly higher in non-survivors than in survivors of sepsis (302.9 versus 208.9, P=0.039; and 244.3 versus 122.8, P<0.0001 respectively). The expression of CTLA-4 statistically correlated with that of LC3II in patients with sepsis, patients with SAI, and patients with SAI who did not survive (correlation coefficient: 0.69, 0.68, and 0.73, respectively, P<0.0001).

Conclusions

CTLA-4 overexpression on CD4+ T cells was markedly associated with the incidence of SAI and had great relevance to 28-day mortality. mTOR pathway mediated autophagic-lysosomal disorder showed significant association with CTLA-4 expression.

The Application Potential of the Regulation of Tregs Function by Irisin in the Prevention and Treatment of Immune-Related Diseases

Irisin is a muscle factor induced by exercise, generated through the proteolytic cleavage of the membrane protein fibronectin type III domain-containing protein 5 (FNDC-5). Numerous studies have shown that irisin plays a significant role in regulating glucose and lipid metabolism, inhibiting oxidative stress, reducing systemic inflammatory responses, and providing neuroprotection. Additionally, irisin can exert immunomodulatory functions by regulating regulatory T cells (Tregs). Tregs are a highly differentiated subset of mature T cells that play a key role in maintaining self-immune homeostasis and are closely related to infections, inflammation, immune-related diseases, and tumors. Irisin exerts persistent positive effects on Treg cell functions through various mechanisms, including regulating Treg cell differentiation and proliferation, improving their function, modulating the balance of immune cells, increasing the production of anti-inflammatory cytokines, and enhancing metabolic functions, thereby helping to maintain immune homeostasis and prevent immune-related diseases. As an important myokine, irisin interacts with receptors on the cell membrane, activating multiple intracellular signaling pathways to regulate cell metabolism, proliferation, and function. Although the specific receptor for irisin has not been fully identified, integrins are considered potential receptors. Irisin activates various signaling pathways, including AMPK, MAPK, and PI3K/Akt, through integrin receptors, thereby exerting multiple biological effects. These research findings provide important clues for understanding the mechanisms of irisin's action and theoretical basis for its potential applications in metabolic diseases and immunomodulation. This article reviews the relationship between irisin and Tregs, as well as the research progress of irisin in immune-related diseases such as multiple sclerosis, myasthenia gravis, acquired immune deficiency syndrome, type 1 diabetes, sepsis, and rheumatoid arthritis. Studies have revealed that irisin plays an important role in immune regulation by improving the function of Tregs, suggesting its potential application value in the treatment of immune-related diseases.

Role of OPG/RANKL/RANK/TLR4 signaling pathway in sepsis-associated acute kidney injury

BACKGROUND

Sepsis-associated acute kidney injury (SA-AKI) has high mortality rates. The osteoprotegerin (OPG)/receptor activator of nuclear factor-κB ligand (RANKL)/receptor activator of nuclear factor-κB (RANK)/Toll-like receptor 4 (TLR4) pathway and its potential role in SA-AKI pathogenesis remain to be fully understood. Herein, we addressed this issue using mouse models.

METHODS

An SA-AKI mouse model was established using the cecal ligation and puncture method (CLP). Mice were grouped into sham, CLP model, CLP + recombinant RANKL, and CLP + anti-RANKL groups. Serum creatinine (Scr) and blood urea nitrogen (BUN) levels were measured to assess kidney function. ELISA was used to detect serum IL-1β, TNF-α, and IL-6 levels. Real-time quantitative PCR and Western blot were used to detect the mRNA and protein expression levels of OPG, RANKL, RANK, and TLR4 in kidney tissues. HE staining was performed to evaluate the pathological changes.

RESULTS

The CLP model group showed higher levels of Scr and BUN, indicating impaired kidney function in SA-AKI, compared to the sham group. Treatment with recombinant RANKL in the CLP + recombinant RANKL group reduced Scr and BUN levels, while anti-RANKL treatment in the CLP + anti-RANKL group elevated their levels. Moreover, the CLP model group had significantly increased IL-1β, TNF-α, and IL-6 than the sham group, indicating elevated inflammation in SA-AKI. The CLP + recombinant RANKL group demonstrated decreased cytokine levels, whereas the CLP + anti-RANKL group showed an increase. Additionally, the histopathological evaluation revealed distinct kidney tissue damage in the CLP model group. Recombinant RANKL treatment reduced this damage, while anti-RANKL treatment exacerbated it. Mechanically, the mRNA and protein expression of RANKL were significantly decreased, while those of OPG, RANK, and TLR4 were significantly increased in the CLP model group and the CLP + anti-RANKL group. Interestingly, treatment with recombinant RANKL reversed these changes, as evidenced by significantly increased RANKL but decreased OPG, RANK, and TLR4.

CONCLUSION

The OPG/RANKL/RANK/TLR4 pathway is involved in SA-AKI pathogenesis. Recombinant RANKL treatment attenuates the inflammatory response and kidney tissue damage in SA-AKI, possibly via regulating this pathway. This pathway shows promise as a therapeutic target for SA-AKI.

RENAL PROTECTIVE EFFECT AND CLINICAL ANALYSIS OF VITAMIN B 6 IN PATIENTS WITH SEPSIS

ABSTRACT

Objective: To investigate the protective effect and possible mechanisms of vitamin B 6 against renal injury in patients with sepsis. Methods: A total of 128 patients with sepsis who met the entry criteria in multiple centers were randomly divided into experimental (intravenous vitamin B 6 therapy) and control (intravenous 0.9% sodium chloride therapy) groups based on usual care. Clinical data, the inflammatory response indicators interleukin 6 (IL-6), interleukin 8 (IL-8), tumor necrosis factor (TNF-α), and endothelin-1 (ET-1), the oxidative stress response indicators superoxide dismutase, glutathione and malondialdehyde, and renal function (assessed by blood urea nitrogen, serum creatinine, and renal resistance index monitored by ultrasound) were compared between the two groups. Results: After 7 d of treatment, the IL-6, IL-8, TNF-α, and ET-1 levels in the experimental group were significantly lower than those in the control group, the oxidative stress response indicators were significantly improved in the experimental group and the blood urea nitrogen, serum creatinine, and renal resistance index values in the experimental group were significantly lower than those in the control group ( P < 0.05). There was no statistical difference between the two groups in the rate of renal replacement therapy and 28 d mortality ( P > 0.05). However, the intensive care unit length of stay and the total hospitalization expenses in the experimental group were significantly lower than those in the control group ( P < 0.05). Conclusion: The administration of vitamin B 6 in the treatment of patients with sepsis attenuates renal injury, and the mechanism may be related to pyridoxine decreasing the levels of inflammatory mediators and their regulation by redox stress.

Clinical biomarker profiles reveals gender differences and mortality factors in sepsis

Background

Sepsis is a major contributor to global morbidity and mortality, affecting millions each year. Notwithstanding the decline in sepsis incidence and mortality over decades, gender disparities in sepsis outcomes persist, with research suggesting higher mortality rates in males.

Methods

This retrospective study aims to delineate gender-specific clinical biomarker profiles impacting sepsis progression and mortality by examining sepsis cases and related clinical data from the past three years. Propensity score matching was used to select age-matched healthy controls for comparison.

Results

Among 265 sepsis patients, a significantly higher proportion were male (60.8%, P<0.001). While mortality did not significantly differ by gender, deceased patients were significantly older (mean 69 vs 43 years, P=0.003), more likely to have hypertension (54% vs 25%, P=0.019), and had higher SOFA scores (mean ~10 vs 4, P<0.01) compared to survivors. Principal Component Analysis (PCA) showed clear separation between sepsis patients and healthy controls. 48 serum biomarkers were significantly altered in sepsis, with Triiodothyronine, Apolipoprotein A, and Serum cystatin C having the highest diagnostic value by ROC analysis. Gender-stratified comparisons identified male-specific (e.g. AFP, HDLC) and female-specific (e.g. Rheumatoid factor, Interleukin-6) diagnostic biomarkers. Deceased patients significantly differed from survivors, with 22 differentially expressed markers; Antithrombin, Prealbumin, HDL cholesterol, Urea nitrogen and Hydroxybutyrate had the highest diagnostic efficiency for mortality.

Conclusion

These findings enhance our understanding of gender disparities in sepsis and may guide future therapeutic strategies. Further research is warranted to validate these biomarker profiles and investigate the molecular mechanisms underlying these gender differences in sepsis outcomes.

Analysis of ceRNA Network and Identification of Potential Treatment Target and Biomarkers of Endothelial Cell Injury in Sepsis

Background: Sepsis is a complex clinical syndrome caused by a dysregulated host immune response to infection. This study aimed to identify a competing endogenous RNA (ceRNA) network that can greatly contribute to understanding the pathophysiological process of sepsis and determining sepsis biomarkers. Methods: The GSE100159, GSE65682, GSE167363, and GSE94717 datasets were obtained from the Gene Expression Omnibus (GEO) database. Weighted gene coexpression network analysis was performed to find modules possibly involved in sepsis. A long noncoding RNA-microRNA-messenger RNA (lncRNA-miRNA-mRNA) network was constructed based on the findings. Single-cell analysis was performed. Human umbilical vein endothelial cells were treated with lipopolysaccharide (LPS) to create an in vitro model of sepsis for network verification. Reverse transcription-polymerase chain reaction, fluorescence in situ hybridization, and luciferase reporter genes were used to verify the bioinformatic analysis. Result: By integrating data from three GEO datasets, we successfully constructed a ceRNA network containing 18 lncRNAs, 7 miRNAs, and 94 mRNAs based on the ceRNA hypothesis. The lncRNA ZFAS1 was found to be highly expressed in LPS-stimulated endothelial cells and may thus play a role in endothelial cell injury. Univariate and multivariate Cox analyses showed that only SLC26A6 was an independent predictor of prognosis in sepsis. Overall, our findings indicated that the ZFAS1/hsa-miR-449c-5p/SLC26A6 ceRNA regulatory axis may play a role in the progression of sepsis. Conclusion: The sepsis ceRNA network, especially the ZFAS1/hsa-miR-449c-5p/SLC26A6 regulatory axis, is expected to reveal potential biomarkers and therapeutic targets for sepsis management.

Unlocking the potential of senescence-related gene signature as a diagnostic and prognostic biomarker in sepsis: insights from meta-analyses, single-cell RNA sequencing, and in vitro experiments

Cellular senescence is closely associated with the pathogenesis of sepsis. However, the diagnostic and prognostic value of senescence-related genes remain unclear. In this study, 866 senescence-related genes were collected from CellAge. The training cohort, GSE65682, which included 42 control and 760 sepsis samples, was obtained from the Gene Expression Omnibus (GEO). Feature selection was performed using gene expression difference detection, LASSO analysis, random forest, and Cox regression. TGFBI and MAD1L1 were ultimately selected for inclusion in the multivariate Cox regression model. Clustering based on the expressions of TGFBI and MAD1L1 was significantly associated with sepsis characteristics and prognoses (all P < 0.05). The risk signature served as a reliable prognostic predictor across the GSE65682, GSE95233, and GSE4607 cohorts (pooled hazard ratio = 4.27; 95% confidence interval [CI] = 1.63-11.17). Furthermore, it also served as a robust classifier to distinguish sepsis samples from control cases across 14 cohorts (pooled odds ratio = 5.88; 95% CI = 3.54-9.77). Single-cell RNA sequencing analyses from five healthy controls and four sepsis subjects indicated that the risk signature could reflect the senescence statuses of monocytes and B cells; this finding was then experimentally validated in THP-1 and IM-9 cells in vitro (both P < 0.05). In all, a senescence-related gene signature was developed as a prognostic and diagnostic biomarker for sepsis, providing cut-in points to uncover underlying mechanisms and a promising clinical tool to support precision medicine.

The prehospital NEW score to assess septic shock in-hospital, 30-day and 90-day mortality

BACKGROUND

The early identification of sepsis presenting a high risk of deterioration is a daily challenge to optimise patient pathway. This is all the most crucial in the prehospital setting to optimize triage and admission into the appropriate unit: emergency department (ED) or intensive care unit (ICU). We report the association between the prehospital National Early Warning Score 2 (NEWS-2) and in-hospital, 30 and 90-day mortality of SS patients cared for in the pre-hospital setting by a mobile ICU (MICU).

METHODS

Septic shock (SS) patients cared for by a MICU between 2016, April 6th and 2021 December 31st were included in this retrospective cohort study. The NEWS-2 is based on 6 physiological variables (blood pressure, heart rate, respiratory rate, temperature, oxygen saturation prior oxygen supplementation, and level of consciousness) and ranges from 0 to 20. The Inverse Probability Treatment Weighting (IPTW) propensity method was applied to assess the association with in-hospital, 30 and 90-day mortality. A NEWS-2 ≥ 7 threshold was chosen for increased clinical deterioration risk definition and usefulness in clinical practice based on previous reports.

RESULTS

Data from 530 SS patients requiring MICU intervention in the pre-hospital setting were analysed. The mean age was 69 ± 15 years and presumed origin of sepsis was pulmonary (43%), digestive (25%) or urinary (17%) infection. In-hospital mortality rate was 33%, 30 and 90-day mortality were respectively 31% and 35%. A prehospital NEWS-2 ≥ 7 is associated with an increase in-hospital, 30 and 90-day mortality with respective RRa = 2.34 [1.39-3.95], 2.08 [1.33-3.25] and 2.22 [1.38-3.59]. Calibration statistic values for in-hospital mortality, 30-day and 90-day mortality were 0.54; 0.55 and 0.53 respectively.

CONCLUSION

A prehospital NEWS-2 ≥ 7 is associated with an increase in in-hospital, 30 and 90-day mortality of septic shock patients cared for by a MICU in the prehospital setting. Prospective studies are needed to confirm the usefulness of NEWS-2 to improve the prehospital triage and orientation to the adequate facility of sepsis.

Multidrug-Resistant Sepsis: A Critical Healthcare Challenge

Sepsis globally accounts for an alarming annual toll of 48.9 million cases, resulting in 11 million deaths, and inflicts an economic burden of approximately USD 38 billion on the United States healthcare system. The rise of multidrug-resistant organisms (MDROs) has elevated the urgency surrounding the management of multidrug-resistant (MDR) sepsis, evolving into a critical global health concern. This review aims to provide a comprehensive overview of the current epidemiology of (MDR) sepsis and its associated healthcare challenges, particularly in critically ill hospitalized patients. Highlighted findings demonstrated the complex nature of (MDR) sepsis pathophysiology and the resulting immune responses, which significantly hinder sepsis treatment. Studies also revealed that aging, antibiotic overuse or abuse, inadequate empiric antibiotic therapy, and underlying comorbidities contribute significantly to recurrent sepsis, thereby leading to septic shock, multi-organ failure, and ultimately immune paralysis, which all contribute to high mortality rates among sepsis patients. Moreover, studies confirmed a correlation between elevated readmission rates and an increased risk of cognitive and organ dysfunction among sepsis patients, amplifying hospital-associated costs. To mitigate the impact of sepsis burden, researchers have directed their efforts towards innovative diagnostic methods like point-of-care testing (POCT) devices for rapid, accurate, and particularly bedside detection of sepsis; however, these methods are currently limited to detecting only a few resistance biomarkers, thus warranting further exploration. Numerous interventions have also been introduced to treat MDR sepsis, including combination therapy with antibiotics from two different classes and precision therapy, which involves personalized treatment strategies tailored to individual needs. Finally, addressing MDR-associated healthcare challenges at regional levels based on local pathogen resistance patterns emerges as a critical strategy for effective sepsis treatment and minimizing adverse effects.

The mortality and years of life lost for community-acquired pneumonia before and during COVID-19 pandemic in China

Background

Community-acquired pneumonia (CAP) is a leading cause of mortality worldwide, but disease burden of CAP is not clear so far. We aim to explore the spatial and temporal trends of mortality and years of life lost (YLL) due to CAP during 2013-2021 in mainland China, especially the mortality changes before and during COVID-19 pandemic due to COVID-19 related non-pharmaceutical interventions (NPIs).

Methods

We used data from the National Mortality Surveillance System to estimate the age-standardized rates of death and YLL of CAP at national and provincial level in China during 2013-2021. Monthly and provincial NPIs data were obtained from Oxford COVID-19 Government Response Tracker. The Average annual percentage change (AAPC) and mortality reduction were estimated by log-linear regression and interrupted time series, respectively.

Findings

In China, most CAP that caused deaths had no clear etiology, and bacterial pneumonia and viral pneumonia were the leading 2 causes among CAP deaths with determined etiology before and during COVID-19 pandemic. The age-standardized CAP mortality rate decreased from 11.18 per 100,000 in 2013 to 8.76 per 100,000 in 2019, and to 5.74 per 100,000 in 2021 (AAPC -4.51% vs -7.89%). Trends were similar in age-standardized rate of YLL. Both rates declined more for viral pneumonia, compared with bacterial pneumonia. After adjusting for NPIs at provincial level after 2020, the NPIs for COVID-19 was associated with significant reductions in CAP mortality (-0.34 per 100,000, -0.41 to -0.27; p < 0.0001), and provinces that economically developed and conducted strict regular NPIs against COVID-19 contributed the most reduction.

Interpretation

We observed a decreasing trend of age-standardized CAP mortality from 2013 to 2019, and a dramatical reduction during COVID-19 pandemic, especially for viral pneumonia. Our study provided the evidence for the effectiveness of regular NPIs on the significant reductions in CAP mortality.

Funding

This work has been supported by Beijing Municipal Science and Technology Project Z191100006619101, Chinese Academy of Medical Sciences (CAMS) Innovation Fund for Medical Sciences (CIFMS 2021-I2M-1-048), CAMS Institute of Respiratory Medicine Grant for Young Scholars (2023-ZF-8) and the New Cornerstone Science Foundation.

Adoptive macrophage directed photodynamic therapy of multidrug-resistant bacterial infection

Multidrug-resistant (MDR) bacteria cause severe clinical infections and a high mortality rate of over 40% in patients with immunodeficiencies. Therefore, more effective, broad-spectrum, and accurate treatment for severe cases of infection is urgently needed. Here, we present an adoptive transfer of macrophages loaded with a near-infrared photosensitizer (Lyso700D) in lysosomes to boost innate immunity and capture and eliminate bacteria through a photodynamic effect. In this design, the macrophages can track and capture bacteria into the lysosomes through innate immunity, thereby delivering the photosensitizer to the bacteria within a single lysosome, maximizing the photodynamic effect and minimizing the side effects. Our results demonstrate that this therapeutic strategy eliminated MDR Staphylococcus aureus (MRSA) and Acinetobacter baumannii (AB) efficiently and cured infected mice in both two models with 100% survival compared to 10% in the control groups. Promisingly, in a rat model of central nervous system bacterial infection, we performed the therapy using bone marrow-divided macrophages and implanted glass fiber to conduct light irradiation through the lumbar cistern. 100% of infected rats survived while none of the control group survived. Our work proposes an efaficient and safe strategy to cure MDR bacterial infections, which may benefit the future clinical treatment of infection.

Hypoxia-inducible factor-1α is a biomarker for predicting patients with sepsis

OBJECTIVE

This study aimed to investigate the potential value of serum hypoxia-inducible factor-1α (HIF-1α) concentrations as a biomarker in patients with sepsis.

METHODS

The enrolled patients were divided into the following four groups: the intensive care unit (ICU) control group (n = 33), infection group (n = 29), septic nonshock group (n = 40), and septic shock group (n = 94). An enzyme-linked immunosorbent assay was used to measure serum HIF-1α concentrations on ICU admission. Clinical parameters and laboratory test results were also collected.

RESULTS

Serum HIF-1α concentrations were significantly higher in the infection group, septic nonshock group, and septic shock group than in the ICU control group. Moreover, HIF-1α concentrations were associated with a better predictive ability for diagnosing sepsis than the Acute Physiology and Chronic Health Evaluation II score, procalcitonin concentrations, and lactate concentrations. Patients with sepsis and HIF-1α concentrations >161.14 pg/mL had a poor prognosis.

CONCLUSIONS

Serum HIF-1α concentrations are a useful biomarker for the diagnosis of sepsis and predicting the prognosis of patients.

Temporal trends of sepsis-related mortality in China, 2006-2020: a population-based study

BACKGROUND

The scarcity of sepsis epidemiologic data from most low- and middle-income countries (LMICs) hampered estimation of regional and global burden of the disease, and provided limited guidance for policy makers. We aimed to characterize and analyze the temporal trends of sepsis-related mortality in China, by population groups, underlying causes of death, geographic regions, and sociodemographic index (SDI) levels.

METHODS

Sepsis-related deaths were identified from the National Mortality Surveillance System (NMSS) of China from 2006 to 2020. Trends of sepsis-related mortality and years of life lost (YLLs), stratified by age, sex, underlying diseases, and regions were analyzed using the Jointpoint regression analysis. We investigated the association of SDI with trends of sepsis-related mortality.

RESULTS

In 2020, sepsis was estimated to be responsible for 986,929 deaths and 17.1 million YLLs in China. Age-standardized sepsis-related mortality significantly declined from 130.2 (95%CI, 129.4-131) per 100,000 population in 2006 to 76.6 (76.3-76.9) in 2020. Age-standardized YLLs decreased from 2172.7 (2169.4-2176) per 100,000 population in 2006 to 1271 (1269.8-1272.2) in 2020. Substantial variations of sepsis-related mortality and YLLs were observed between population groups and regions, with higher burden in males, the elderly, and western China. An inverse relation was noted between SDI and sepsis-related mortality or YLLs.

CONCLUSIONS

Despite declining trends of age-standardized mortality and YLLs of sepsis in China, significant disparities between population groups and regions highlight a need for targeted policies and measures to close the gaps and improve the outcome of sepsis.

Influence of gender on age-associated in-hospital mortality in patients with sepsis and septic shock: a prospective nationwide multicenter cohort study

BACKGROUND

Numerous epidemiological studies investigating gender-dependent clinical outcomes in sepsis have shown conflicting evidence. This study aimed to investigate the effect of gender on in-hospital mortality due to sepsis according to age group.

METHODS

This study used data from the Korean Sepsis Alliance, an ongoing nationwide prospective multicenter cohort from 19 participating hospitals in South Korea. All adult patients diagnosed with sepsis in the emergency departments of the participating hospitals between September 2019 and December 2021 were included in the analysis. Clinical characteristics and outcomes were compared between male and female. Eligible patients were stratified by age into 19-50 years, 50-80 years, and ≥ 80 years old individuals.

RESULTS

During the study period, 6442 patients were included in the analysis, and 3650 (56.7%) were male. The adjusted odds ratio (OR) [95% confidence interval (CI)] for in-hospital mortality for male compared with female was 1.15 (95% CI = 1.02-1.29). Interestingly, in the age 19-50 group, the risk of in-hospital mortality for males was significantly lower than that of females [0.57 (95% CI = 0.35-0.93)]. For female, the risk of death remained relatively stable until around age 80 (P for linearity = 0.77), while in males, there was a linear increase in the risk of in-hospital death until around age 80 (P for linearity < 0.01). Respiratory infection (53.8% vs. 37.4%, p < 0.01) was more common in male, whereas urinary tract infection (14.7% vs. 29.8%, p < 0.01) was more common in female. For respiratory infection, male had significantly lower in-hospital mortality than female in the age 19-50 groups (adjusted OR = 0.29, 95% CI = 0.12-0.69).

CONCLUSIONS

Gender may influence age-associated sepsis outcomes. Further studies are needed to replicate our findings and fully understand the interaction of gender and age on the outcomes of patients with sepsis.

Predictive value of risk factors for prognosis of patients with sepsis in intensive care unit

Sepsis has emerged as a major global public health concern due to its elevated mortality and high cost of care. This study aimed to evaluate the risk factors associated with the mortality of sepsis patients in the Intensive Care Unit (ICU), and to intervene in the early stages of sepsis in order to improve patient outcomes and reduce mortality. From January 1st, 2021 to December 31st, 2021, Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Huashan Hospital Affiliated to Fudan University, and The Seventh People's Hospital Affiliated to Shanghai University of Traditional Chinese Medicine were designated as sentinel hospitals, and sepsis patients in their respective ICU and Emergency ICU were selected as research subjects, and divided into survivors and non-survivors according to their discharge outcomes. The mortality risk of sepsis patients was subsequently analyzed by logistic regression. A total of 176 patients with sepsis were included, of which 130 (73.9%) were survivors and 46 (26.1%) were non-survivors. Factors identified as having an impact on death among sepsis patients included female [Odds Ratio (OR) = 5.135, 95% confidence interval (CI): 1.709, 15.427, P = .004)], cardiovascular disease (OR = 6.272, 95% CI: 1.828, 21.518, P = .004), cerebrovascular disease (OR = 3.133, 95% CI: 1.093, 8.981, P = .034), pulmonary infections (OR = 6.700, 95% CI: 1.744, 25.748, P = .006), use of vasopressors (OR = 34.085, 95% CI: 10.452, 111.155, P < .001), WBC < 3.5 × 109/L (OR = 9.752, 95% CI: 1.386, 68.620, P = .022), ALT < 7 U/L (OR = 7.672, 95% CI: 1.263, 46.594, P = .027), ALT > 40 U/L (OR = 3.343, 95% CI: 1.097, 10.185, P = .034). Gender, cardiovascular disease, cerebrovascular disease, pulmonary infections, the use of vasopressors, WBC, and ALT are important factors in evaluating the prognostic outcome of sepsis patients in the ICU. This suggests that medical professionals should recognize them expeditiously and implement aggressive treatment tactics to diminish the mortality rate and improve outcomes.

Application Prospect of the SOFA Score and Related Modification Research Progress in Sepsis

In 2016, the SOFA score was proposed as the main evaluation system for diagnosis in the definition of sepsis 3.0, and the SOFA score has become a new research focus in sepsis. Some people are skeptical about diagnosing sepsis using the SOFA score. Experts and scholars from different regions have proposed different, modified versions of SOFA score to make up for the related problems with the use of the SOFA score in the diagnosis of sepsis. While synthesizing the different improved versions of SOFA proposed by experts and scholars in various regions, this paper also summarizes the relevant definitions of sepsis put forward in recent years to build a clear, improved application framework of SOFA score. In addition, the comparison between machine learning and SOFA scores related to sepsis is described and discussed in the article. Taken together, by summarizing the application of the improved SOFA score proposed in recent years in the related definition of sepsis, we believe that the SOFA score is still an effective means of diagnosing sepsis, but in the process of the continuous refinement and development of sepsis in the future, the SOFA score needs to be further refined and improved to provide more accurate coping strategies for different patient populations or application directions regarding sepsis. Against the big data background, machine learning has immeasurable value and significance, but its future applications should add more humanistic references and assistance.

Case report: Concurrent pylephlebitis and subarachnoid hemorrhage in an octogenarian patient with Escherichia coli sepsis

Background

Pylephlebitis refers to an infective suppurative thrombosis that occurs in the portal vein and its branches. Concurrent pylephlebitis and subarachnoid hemorrhage (SAH) are rare but fatal for patients with sepsis. This scenario drives the clinicians into a dilemma of how to deal with coagulation and bleeding simultaneously.

Case summary

An 86-year-old man was admitted to hospital for chills and fever. After admission, he developed headache and abdominal distension. Neck stiffness, Kernig's and Brudzinski's sign were present. Laboratory tests discovered decreased platelet count, elevated inflammatory parameters, aggravated transaminitis, and acute kidney injury. Escherichia coli (E. coli) were identified in blood culture. Computed tomography (CT) revealed thrombosis in the superior mesenteric vein and portal veins. Lumbar puncture and Brain CT indicated SAH. The patient had eaten cooked oysters prior to illness. It was speculated that the debris from oyster shell might have injured his intestinal mucosa and resulted in bacterial embolus and secondary thrombosis in portal veins. The patient was treated with effective antibiotics, fluid resuscitation, and anticoagulation. The dose titration of low molecular weight heparin (LMWH) under close monitoring attributed to diminution of the thrombosis and absorption of SAH. He recovered and was discharged after 33-day treatment. One-year follow-up indicated that the post-discharge course was uneventful.

Conclusion

This report describes a case of an octogenarian with E. coli septicemia who survived from concurrent pylephlebitis and SAH along with multiple organ dysfunction syndrome. For such patients with life-threatening complications, even in the acute stage of SAH, decisive employment of LMWH is essential to resolve thrombosis and confers a favorable prognosis.

Association between hyperuricemia and acute kidney injury in critically ill patients with sepsis

BACKGROUND

Sepsis-related AKI is related to short-term mortality and poor long-term prognoses, such as chronic renal insufficiency, late development of end-stage renal disease, and long-term mortality. In this study, we aimed to investigate the association of hyperuricemia with acute kidney injury (AKI) in patients with sepsis.

METHODS

The retrospective cohort study included 634 adult sepsis patients hospitalized in the intensive care unit (ICU) of the First Affiliated Hospital of Guangxi Medical University from March 2014 to June 2020 and the ICU of the Second Affiliated Hospital of Guangxi Medical University from January 2017 to June 2020. Based on the first serum uric acid level within 24 h of admission to the ICU, patients were divided into groups with or without hyperuricemia, and the incidence of AKI within seven days of ICU admission was compared between the two groups. The univariate analysis analyzed the effect of hyperuricemia on sepsis-related AKI, and the multivariable logistic regression model analysis was used.

RESULTS

Among the 634 patients with sepsis, 163 (25.7%) developed hyperuricemia, and 324 (51.5%) developed AKI. The incidence of AKI in the groups with and without hyperuricemia was 76.7% and 42.3%, respectively, with statistically significant differences (2 = 57.469, P < 0.001). After adjusting for genders, comorbidities (coronary artery disease), organ failure assessment (SOFA) score on the day of admission, basal renal function, serum lactate, calcitonin, and mean arterial pressure, hyperuricemia was showed to be an independent risk factor for AKI in patients with sepsis (OR = 4.415, 95%CI 2.793 ~ 6.980, P < 0.001). For every 1 mg/dL increase in serum uric acid in patients with sepsis, the risk of AKI increased by 31.7% ( OR = 1.317, 95%CI 1.223 ~ 1.418, P < 0.001).

CONCLUSION

AKI is a common complication in septic patients hospitalized in the ICU, and hyperuricemia is an independent risk factor for AKI in septic patients.

Technical Innovation in Critical Care in a World of Constraints: Lessons from the COVID-19 Pandemic

The COVID-19 crisis was characterized by a massive need for respiratory support, which has unfortunately not been met globally. This situation mimicked those which gave rise to critical care in the past. Since the polio epidemic in the 50's, the technological evolution of respiratory support has enabled health professionals to save the lives of critically-ill patients worldwide every year. However, much of the current innovation work has turned around developing sophisticated, complex, and high-cost standards and approaches whose resilience is still questionable upon facing constrained environments or contexts, as seen in resuscitation work outside intensive care units, during pandemics, or in low-income countries. Ventilatory support is an essential life-saving tool for patients with respiratory distress. It requires an oxygen source combined to a ventilatory assistance device, an adequate monitoring system, and properly trained caregivers to operate it. Each of these elements can be subject to critical constraints, which we can no longer ignore. The innovation process should incorporate them as a prima materia, whilst focusing on the core need of the field using the concept of frugal innovation. Having a universal access to oxygen and respiratory support, irrespective of the context and constraints, necessitates: i) developing cost-effective, energy-efficient, and maintenance-free oxygen generation devices; ii) improving the design of non-invasive respiratory devices (for example, with oxygen saving properties); iii) conceiving fully frugal ventilators and universal monitoring systems; iv) broadening ventilation expertise by developing end-user training programs in ventilator assistance. The frugal innovation approach may give rise to a more resilient and inclusive critical care system. This paradigm shift is essential for the current and future challenges.

Heme oxygenase‑1 inhibits renal tubular epithelial cell pyroptosis by regulating mitochondrial function through PINK1

Endotoxin-induced acute kidney injury (AKI) is commonly observed in clinical practice. Renal tubular epithelial cell (RTEC) pyroptosis is one of the main factors leading to the development of endotoxin-induced AKI. Mitochondrial dysfunction can lead to pyroptosis. However, the biological pathways involved in the potential lipopolysaccharide (LPS)-induced pyroptosis of RTECs, notably those associated with mitochondrial dysfunction, are poorly understood. Previous studies have demonstrated that heme oxygenase (HO)-1 confers cell protection via the induction of PTEN-induced putative kinase 1 (PINK1) expression through PTEN to regulate mitochondrial fusion/fission during endotoxin-induced AKI in vivo. Therefore, the present study investigated the role of HO-1/PINK1 in maintaining mitochondrial function and inhibiting the pyroptosis of RTECs exposed to LPS. Primary cultures of RTECs were obtained from wild-type (WT) and PINK1-knockout (PINK1KO) rats. An in vitro model of endotoxin-associated RTEC injury was established following treatment of the cells with LPS. The WT RTECs were divided into the control, LPS, Znpp + LPS and Hemin + LPS groups, and the PINK1KO RTECs were divided into the control, LPS and Hemin + LPS groups. RTECs were exposed to LPS for 6 h to assess cell viability, inflammation, pyroptosis and mitochondrial function. In the LPS-treated RTECs, the mRNA and protein expression levels of HO-1 and PINK1 were upregulated. Cell viability, adenosine triphosphate (ATP) levels and the mitochondrial oxygen consumption rate were decreased, whereas the inflammatory response, pyroptosis and mitochondrial reactive oxygen species (ROS) levels were increased. The cell inflammatory response and the induction of pyroptosis were inhibited, whereas the levels of mitochondrial ROS were decreased. In addition, the cell viability and ATP levels were increased in the WT RTECs following the upregulation of HO-1 expression. These effects were reversed by the downregulation of HO-1 expression. However, no statistically significant differences were noted between the LPS and the Hemin + LPS groups in the PINK1KO RTECs. Collectively, the findings of the present study indicate that HO-1 inhibits inflammation and regulates mitochondrial function by inhibiting the pyroptosis of LPS-exposed RTECs via PINK1.

Safety, tolerability, pharmacokinetics, and efficacy of kukoamine B in patients with sepsis: A randomized phase IIa trial

PURPOSE

To evaluate the safety, tolerability, pharmacokinetics, and efficacy of kukoamine B (KB), an alkaloid compound with high affinity for both lipopolysaccharide (LPS) and oligodeoxynucle-otides containing CpG motifs (CpG DNA), in patients with sepsis-induced organ failure.

MATERIALS AND METHODS

This was a multicenter, randomized, double-blind, placebo-controlled phase IIa trial. Patients with sepsis-induced organ failure were randomized to receive either KB (0.06, 0.12, or 0.24 mg/kg) or placebo, every 8 h for 7 days. Primary endpoint was safety, and secondary endpoints included pharmacokinetic (PK) parameters, changes in inflammatory mediators' level, and prognostic parameters.

RESULTS

Of 44 patients enrolled, adverse events occurred in 28 patients [n = 20, 66.7% (KB pooled); n = 8, 57.1% (placebo)], while treatment emergent adverse events were reported in 14 patients [n = 10, 33.3% (KB pooled); n = 4, 28.6% (placebo)]. Seven patients died at 28-day follow-up [n = 4, 13.3% (KB pooled); n = 3, 21.4% (placebo)], none was related to study drug. PK parameters suggested dose-dependent drug exposure and no drug accumulation. KB did not affect clinical outcomes such as ΔSOFA score, vasopressor-free days or ventilator-free days.

CONCLUSIONS

In patients with sepsis-induced organ failure, KB was safe and well tolerated. Further investigation is warranted.

TRIAL REGISTRATION

http://ClinicalTrials.gov, NCT03237728.

Identification of potential biomarkers and pathways for sepsis using RNA sequencing technology and bioinformatic analysis

Long non-coding RNAs (lncRNAs) has been proven by many to play a crucial part in the process of sepsis. To obtain a better understanding of sepsis, the molecular biomarkers associated with it, and its possible pathogenesis, we obtained data from RNA-sequencing analysis using serum from three sepsis patients and three healthy controls (HCs). Using edgeR (one of the Bioconductor software package), we identified 1118 differentially expressed mRNAs (DEmRNAs) and 1394 differentially expressed long noncoding RNAs (DElncRNAs) between sepsis patients and HCs. We identified the biological functions of these disordered genes using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway analyses. The GO analysis showed that the homophilic cell adhesion via plasma membrane adhesion molecules was the most significantly enriched category. The KEGG signaling pathway analysis indicated that the differentially expressed genes (DEGs) were most significantly enriched in retrograde endocannabinoid signaling. Using STRING, a protein-protein interaction network was also created, and Cytohubba was used to determine the top 10 hub genes. To examine the relationship between the hub genes and sepsis, we examined three datasets relevant to sepsis that were found in the gene expression omnibus (GEO) database. PTEN and HIST2H2BE were recognized as hub gene in both GSE4607, GSE26378, and GSE9692 datasets. The receiver operating characteristic (ROC) curves indicate that PTEN and HIST2H2BE have good diagnostic value for sepsis. In conclusion, this two hub genes may be biomarkers for the early diagnosis of sepsis, our findings should deepen our understanding of the pathogenesis of sepsis.

National incidence and mortality of hospitalized sepsis in China

BACKGROUND

Sepsis is a leading cause of preventable death around the world. Population-based estimation of sepsis incidence is lacking in China. In this study, we aimed to estimate the population-based incidence and geographic variation of hospitalized sepsis in China.

METHODS

We retrospectively identified hospitalized sepsis from the nationwide National Data Center for Medical Service (NDCMS) and the National Mortality Surveillance System (NMSS) by ICD-10 codes for the period from 2017 to 2019. In-hospital sepsis case fatality and mortality rate were calculated to extrapolate the national incidence of hospitalized sepsis. The geographic distribution of hospitalized sepsis incidence was examined using Global Moran's Index.

RESULTS

We identified 9,455,279 patients with 10,682,625 implicit-coded sepsis admissions in NDCMS and 806,728 sepsis-related deaths in NMSS. We estimated that the annual standardized incidence of hospitalized sepsis was 328.25 (95% CI 315.41-341.09), 359.26 (95% CI 345.4-373.12) and 421.85 (95% CI 406.65-437.05) cases per 100,000 in 2017, 2018 and 2019, respectively. We observed 8.7% of the incidences occurred among neonates less than 1 year old, 11.7% among children aged 1-9 years, and 57.5% among elderly older than 65 years. Significant spatial autocorrelation for incidence of hospitalized sepsis was observed across China (Moran's Index 0.42, p = 0.001; 0.45, p = 0.001; 0.26, p = 0.011 for 2017, 2018, 2019, respectively). Higher number of hospital bed supply and higher disposable income per capita were significantly associated with a higher incidence of hospitalized sepsis.

CONCLUSION

Our study showed a greater burden of sepsis hospitalizations than previous estimated. The geographical disparities suggested more efforts were needed in prevention of sepsis.

Spatial, temporal and demographic patterns in asthma mortality in China: A systematic analysis from 2014 to 2020

Background

Asthma is an important contributor to the burden of non-communicable diseases in China. Understanding spatial, temporal, and demographic patterns in asthma mortality is relevant to the design and implementation of targeted interventions.

Methods

This study collected information on asthma deaths occurring across 605 disease surveillance points (DSPs) as recorded in the population-based national mortality surveillance system (NMSS) of China. Asthma was defined according to the International Classification of Diseases, 10th Revision code J45-J46. Estimates of age-standardized mortality rates and total national asthma deaths were calculated based on yearly population data. Statistical analysis was performed to investigate the influence of various factors on asthma mortality.

Results

Between 2014 and 2020, a total of 40 116 asthma deaths occurred in DSPs. Standardized asthma mortality per 100 000 people decreased from 1.79 (95% CI: 1.74-1.83) in 2014 to 1.07 (95% CI: 1.03-1.10) in 2020 in China. In 2020, the overall asthma mortality rate was higher for male patients than for female patients, and asthma mortality rates increased substantially with age. Age-standardized asthma mortality per 100,000 people exhibited significant geographic variation, ranging from 0.93 (95% CI: 0.89-0.98) in Eastern China to 1.04 (95% CI: 0.98-1.10) in Central China and 1.37 (95% CI: 1.29-1.45) in Western China in 2020. Asthma mortality in urban areas appeared to be higher than in rural areas. Socioeconomic factors, including gross domestic product per capita and density of hospital beds per 10,000 population, may be related to asthma mortality. Male asthma patients who lived in rural areas and were aged 65 years and above were generally at high risk of asthma-related mortality.

Conclusions

This study found a spatial and temporal trend for a reduction in asthma deaths over seven years in China; however, there remain important sociodemographic groups that have not secured the same decrease in mortality rates.

Trial registration

This was a purely observational study and thus registration was not required.

CTSB promotes sepsis-induced acute kidney injury through activating mitochondrial apoptosis pathway

Background

Acute kidney injury is a common and severe complication of sepsis. Sepsis -induced acute kidney injury(S-AKI) is an independent risk factor for mortality among sepsis patients. However, the mechanisms of S-AKI are complex and poorly understand. Therefore, exploring the underlying mechanisms of S-AKI may lead to the development of therapeutic targets.

Method

A model of S-AKI was established in male C57BL/6 mice using cecal ligation and puncture (CLP). The data-independent acquisition (DIA)-mass spectrometry-based proteomics was used to explore the protein expression changes and analyze the key proteomics profile in control and CLP group. The methodology was also used to identify the key proteins and pathways. S-AKI in vitro was established by treating the HK-2 cells with lipopolysaccharide (LPS). Subsequently, the effect and mechanism of Cathepsin B (CTSB) in inducing apoptosis in HK-2 cells were observed and verified.

Results

The renal injury scores, serum creatinine, blood urea nitrogen, and kidney injury molecule 1 were higher in septic mice than in non-septic mice. The proteomic analysis identified a total of 449 differentially expressed proteins (DEPs). GO and KEGG analysis showed that DEPs were mostly enriched in lysosomal-related cell structures and pathways. CTSB and MAPK were identified as key proteins in S-AKI. Electron microscopy observed enlarged lysosomes, swelled and ruptured mitochondria, and cytoplasmic vacuolization in CLP group. TUNEL staining and CTSB activity test showed that the apoptosis and CTSB activity were higher in CLP group than in control group. In HK-2 cell injury model, the CTSB activity and mRNA expression were increased in LPS-treated cells. Acridine orange staining showed that LPS caused lysosomal membrane permeabilization (LMP). CA074 as an inhibitor of CTSB could effectively inhibit CTSB activity. CCK8 and Annexin V/PI staining results indicated that CA074 reversed LPS-induced apoptosis of HK-2 cells. The JC-1 and western blot results showed that LPS inhibited mitochondrial membrane potential and activated mitochondrial apoptosis pathway, which could be reversed by CA074.

Conclusions

LMP and CTSB contribute to pathogenesis of S-AKI. LPS treatment induced HK-2 cell injury by activating mitochondrial apoptosis pathway. Inhibition of CTSB might be a new therapeutic strategy to alleviate sepsis-induced acute kidney injury.

Research frontiers and trends in the application of artificial intelligence to sepsis: A bibliometric analysis

Background

With the increasing interest of academics in the application of artificial intelligence to sepsis, thousands of papers on this field had been published in the past few decades. It is difficult for researchers to understand the themes and latest research frontiers in this field from a multi-dimensional perspective. Consequently, the purpose of this study is to analyze the relevant literature in the application of artificial intelligence to sepsis through bibliometrics software, so as to better understand the development status, study the core hotspots and future development trends of this field.

Methods

We collected relevant publications in the application of artificial intelligence to sepsis from the Web of Science Core Collection in 2000 to 2021. The type of publication was limited to articles and reviews, and language was limited to English. Research cooperation network, journals, cited references, keywords in this field were visually analyzed by using CiteSpace, VOSviewer, and COOC software.

Results

A total of 8,481 publications in the application of artificial intelligence to sepsis between 2000 and 2021 were included, involving 8,132 articles and 349 reviews. Over the past 22 years, the annual number of publications had gradually increased exponentially. The USA was the most productive country, followed by China. Harvard University, Schuetz, Philipp, and Intensive Care Medicine were the most productive institution, author, and journal, respectively. Vincent, Jl and Critical Care Medicine were the most cited author and cited journal, respectively. Several conclusions can be drawn from the analysis of the cited references, including the following: screening and identification of sepsis biomarkers, treatment and related complications of sepsis, and precise treatment of sepsis. Moreover, there were a spike in searches relating to machine learning, antibiotic resistance and accuracy based on burst detection analysis.

Conclusion

This study conducted a comprehensive and objective analysis of the publications on the application of artificial intelligence in sepsis. It can be predicted that precise treatment of sepsis through machine learning technology is still research hotspot in this field.

Clinical Characteristics and the Effect of Timing for Metagenomic Next-Generation Sequencing in Critically Ill Patients with Sepsis

Background

Metagenomic next-generation sequencing (mNGS) has a good performance for the identification of pathogens in infectious diseases, but few studies on the clinical characteristics of mNGS and the effect of timing for mNGS in critically ill patients with sepsis.

Methods

We retrospectively included all patients diagnosed with sepsis after admission to the intensive care unit (ICU) of a university-affiliated hospital between Aug 1, 2019 and Apr 1, 2021. During the study period, pathogens for all enrolled subjects were obtained by mNGS. We analyzed the composition and positive rate of different samples type for mNGS. And then we used the univariable and multivariable logistic regression to explore the risk factors associated with all-cause mortality at 28 days.

Results

A total of 87 patients were included and 87 samples were analyzed among these patients. The most common sample for mNGS was bronchoalveolar lavage fluid (BALF), about 84% (73/87). The positive rate of pathogens identification by mNGS was higher than conventional culture (92% vs 36%, p < 0.001). In addition to the pathogens detected by conventional culture, mNGS can detect more viruses and fungi. Based on the mNGS report, clinicians made adjustments to the antibiotic regimen for 72% patients. The multivariate binary logistic regression analysis suggested that age (OR, 1.036; 95% CI, 1.005-1.067; p = 0.021) and the sequential organ failure assessment (SOFA) score on the day of mNGS sampling were independent risk factors of death at 28 days (OR, 1.204; 95% CI, 1.038-1.397; p = 0.014).

Conclusion

In critically ill patients with sepsis, the most common sample type for mNGS was BALF, and the positive rate of mNGS is higher than conventional cultures, especially in viruses and fungi. Meanwhile, mNGS can guide clinicians in adjusting antibiotic regimens. Age and the SOFA score on the day of mNGS sampling were independent risk factors for death.

Epidemiology of sepsis in Beijing from 2012 to 2018: analysis of hospital homepage databases derived from the Beijing Public Health System

BACKGROUND

We aimed to evaluate the epidemiology of sepsis in secondary and tertiary hospitals in Beijing, China between 2012 and 2018 using information derived from the Beijing Public Health System.

METHODS

The Beijing Public Health System accessed hospital homepage databases and identify patients who diagnosed sepsis or associated condition according to the International Classification of Diseases, 10th Edition, Clinical Modification codes. There are 125 hospitals involved in this study, including 61 secondary hospitals, accounting for 49.2%, and 63 tertiary hospitals, accounting for 50.8%. Patients were stratified by age as minors (0-17 years old), adults (18-64 years old), seniors (65-84 years old), and the elderly (≥ 85 years old). Patient's demographic information, treatments, outcomes, and all-cause hospitalization cost were evaluated.

RESULTS

This study involved 8,597 patients. Patients treated in tertiary hospitals or received blood transfusion decreased with age, while patients who were male, received ventilation, or took Traditional Chinese Medicine, and in-hospital mortality and hospitalization cost, increased with age. There were 2,729 (31.7%) deaths in this study. A slight increase in in-hospital mortality occurred from 2012 to 2018. Median hospitalization cost for all patients was ¥29,453 (15,011, 65,237). Hospitalization cost showed no significant change from 2012 to 2016, but increased in 2017 and 2018.

CONCLUSION

Sepsis is associated with high mortality and cost. From 2012 to 2018, in-hospital mortality and hospitalization cost of sepsis in Beijing increased significantly with age, and slightly by year.

Abietic acid attenuates sepsis-induced lung injury by inhibiting nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway to inhibit M1 macrophage polarization

Lung injury is one of the leading causes of death in sepsis. Abietic acid (AA) has demonstrated anti-inflammatory and bacteriostatic properties. Herein, we established a mouse model of sepsis by cecal ligation and puncture, and intraperitoneally injected AA to treat. Lung injury was assessed by H&E staining and the inflammation in bronchoalveolar lavage fluid (BALF) were assessed by counting the number of inflammatory cells and detecting the content of inflammatory factors. Meanwhile, we also designed to study the effect of AA on lipopolysaccharide (LPS)-induced inflammatory response and macrophage marker gene expression in RAW264.7 cells in vitro. In this study, we found that AA inhibited LPS-induced secretion of inflammatory mediators (IL-1β, TNF-α, IL-6 and MIP-2), and decreased the expression of M1 macrophage e markers (CD16 and iNOS) and p-p65 protein, while increased the expression of M2 macrophage markers (CD206 and Arg-1) in RAW264.7 cells in vitro. In vivo, the therapy of AA not only rescued septic animals, but also attenuated lung injury in sepsis mice. Moreover, AA decreased the number of total cells, neutrophils and macrophages, the conceration of total protein, and the levels of inflammatory mediators in BALF of sepsis mice. Further, we found that AA inhibited M1 macrophage polarization and blocked nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway in BALF of sepsis mice. In conclusion, Abietic acid attenuates sepsis-induced lung injury, and its mechanism may be related to reducing inflammation by inhibiting NF-κB signaling to inhibit M1 macrophage polarization.

A Robust and Generalizable Immune-Related Signature for Sepsis Diagnostics

High-throughput sequencing can detect tens of thousands of genes in parallel, providing opportunities for improving the diagnostic accuracy of multiple diseases including sepsis, which is an aggressive inflammatory response to infection that can cause organ failure and death. Early screening of sepsis is essential in clinic, but no effective diagnostic biomarkers are available yet. Here, we present a novel method, Recurrent Logistic Regression, to identify diagnostic biomarkers for sepsis from the blood transcriptome data. A panel including five immune-related genes, LRRN3, IL2RB, FCER1A, TLR5, and S100A12, are determined as diagnostic biomarkers (LIFTS) for sepsis. LIFTS discriminates patients with sepsis from normal controls in high accuracy (AUROC = 0.9959 on average; IC = [0.9722-1.0]) on nine validation cohorts across three independent platforms, which outperforms existing markers. Our analysis determined an accurate prediction model and reproducible transcriptome biomarkers that can lay a foundation for clinical diagnostic tests and biological mechanistic studies.

High-dose vitamin C on sepsis: Protocol of a prospective, multi-centered, double-blinded, randomized, and placebo-controlled superiority study

Background

Sepsis is an inflammatory syndrome with life-threatening organ dysfunction and high mortality. In the recent 10 years, high-dose intravenous injection of vitamin C, the first-line antioxidant of humans, has received highlighted attention in the field of critical care. The study aims to examine the efficacy and safety of high-dose intravenous injection of vitamin C in the treatment of sepsis.

Methods and design

Here, we are conducting a prospective, multi-centered, double-blinded, randomized, and placebo-controlled superiority study named High-Dose Vitamin C on Sepsis (HDVCOS). A total of 620 participants diagnosed with sepsis in four participating sites across China that satisfy the eligibility criteria will be randomized at a ratio of 1:1 to receive treatment with a high-dose intravenous injection of vitamin C (200 mg/kg/24 h) or placebo (saline) for 4 days. The primary outcome is 28 days of mortality. The secondary outcomes include the incidence of organ failure, Sequential Organ Failure Assessment (SOFA) score change, organ support, the relationship between plasma vitamin C concentration and outcomes, and adverse events.

Conclusion

The findings of this study will provide potential evidence for high-dose intravenous injection of vitamin C in the treatment of sepsis.

Clinical trial registration

[http://www.chictr.org.cn/showprojen.aspx?proj=29851], identifier [ChiCTR1800017633].

Epidemiological analysis of septic shock in the plateau region of China

Purpose

Little epidemiological data exist on patients with severe infection in the plateau region of China, and the data that do exist are lacking in quality. Using the medical records of patients with severe infection in the Department of Intensive Medicine (intensive care unit; ICU) of the People's Hospital of Tibet Autonomous Region, this study analyzed the epidemiological and clinical characteristics of patients with septic shock in plateau area (Tibet), with the ultimate aim of reducing the incidence and mortality from this condition.

Methods

Clinical data on 137 patients with septic shock in the studied ICU from November 2017 to October 2019 were retrospectively analyzed using SPSS, Version 21.0.

Results

Among the 137 patients with septic shock, there were 47 survivors and 90 in-hospital or post-discharge deaths. There were 91 male patients and 46 female patients. The incidence of septic shock was 11.3%, and mortality rate was 65.7%. Median age was 55 years old, median APACHE-II score on the day of admission was 17, median SOFA score was 11, and median number of organ injuries was one. APACHE-II score (P = 0.02), SOFA score (P &lt; 0.001), and the number of organ injuries (P &lt; 0.001) were higher among patients who died than among survivors. The infections were mainly pulmonary and abdominal, and the main pathogen was gram-negative bacteria.

Conclusion

The incidence and mortality of septic shock in ICU wards in Tibet are very high. The APACHE-II score, SOFA score, and the number of organ damage on the first day after diagnosis are independent risk factors for septic shock. To some extent, this study reflects the epidemiological characteristics of septic shock in the plateau region of China (≥ 3,650 m above sea level) and provides data that can support the prevention and treatment of sepsis in the future. More and deeper epidemiological studies of septic shock are necessary.

Asthma mortality among children and adolescents in China, 2008-2018

BACKGROUND

Asthma mortality among children and adolescents at the national level in China was unreported. The aim of this study was to analyze the mortality of asthma among children and adolescents in China using a nationally representative database.

METHODS

This was a descriptive study using data from the Disease Surveillance Points (DSPs) system. All asthma-related deaths among children and adolescents aged 0-19 years occurring in DSPs across China from 2008 to 2018 were included. Multilevel Poisson regression models were used to compute the total, age-, gender-, region- and residence-specific asthma mortality rates and to investigate the significance of trends and factors associated with asthma mortality. Data from the National Bureau of Statistics were used to estimate the national asthma deaths.

RESULTS

Total asthma mortality rate among Chinese children and adolescents fluctuated between 0.020 (0.009, 0.045) and 0.059 (0.025, 0.137) per 100,000 and showed an overall downward trend (RR, 0.909; 95% CI 0.854-0.968) during the study period (2008-2018). Asthma mortality rate was higher in the western China (RR 2.356, 95% CI 1.513, 3.669) and varied over a ninefold range among DSPs in China. The estimated number of deaths decreased by 51.38% from 2008 (n = 148; 95% CI 58,379) to 2018 (n = 71; 95% CI 34, 109).

CONCLUSIONS

Asthma mortality rate among children and adolescents in China was at a low level compared to rates worldwide and decreased significantly from 2008 to 2018. Compared with most countries in the world, the number of asthma deaths was higher in China.

Potential clinical impact of metagenomic next-generation sequencing of plasma for cervical spine injury with sepsis in intensive care unit: A retrospective study

Cervical spine injury (CSI) accounts for significant mortality in the intensive care unit (ICU), whereas sepsis remains one of the major causes of death in patients with CSI. However, there is no effective method to diagnose sepsis timely. The aim of this study is to investigate the effect of metagenomic next-generation sequencing (mNGS) on the pathogen features and the prognostic prediction of CSI patients with sepsis. A total of 27 blood samples from 17 included patients were tested by mNGS. Data of mNGS were compared with the conventional culture method. The Kaplan–Meier plots were used to visualize survival curves. A Cox proportional hazards model was used to identify independent prognostic factors for survival. Results showed that mNGS detected a wide spectrum of pathogens in CSI patients with sepsis, including 129 bacterial species, 8 viral species, and 51 fungal species. mNGS indicated 85.2% positive results, while the conventional culture method only showed 11.1% positive results in the blood samples. Further analyses revealed that mNGS had no prognostic effect on the septic CSI patients in ICU, whereas positive results of blood culture were closely correlated with an increased hazard ratio (HR) (HR 77.7067, 95%CI 2.860–2641.4595, p = 0.0155). Our results suggested that the mNGS application may provide evidence for clinicians to use antibiotics when a CSI case is diagnosed with sepsis.

Evaluation Value of Serum miR-4299 and miR-16-5p in Risk Stratification of Sepsis-Induced Acute Kidney Injury

Objective

This study was designed to determine the evaluation value of serum miR-4299 and miR-16-5p in risk stratification of sepsis-induced acute kidney injury (SI-AKI).

Methods

A total of 115 sepsis patients were enrolled and assigned to the SI-AKI group (n = 64) or the sepsis-non-AKI group (n = 51) based on the occurrence of AKI, and 72 healthy individuals were enrolled. Fasting venous blood was sampled from every patient before admission, before therapy, and after therapy, followed by quantification of miR-4299 and miR-16-5p by fluorescence quantitative PCR. Receiver operating characteristic (ROC) curves were drawn to evaluate the value of serum miR-16-5p and miR-4299 expression in predicting SI-AKI, and Pearson's correlation analysis was performed to explore the associations of the two with Scr, Cys-C, and KIM-1.

Results

Cases with sepsis, especially SI-AKI, presented significantly downregulated serum miR-4299 and miR-16-5p. After therapy, the expression in them increased. The area under curve (AUC) of serum miR-4299 and miR-16-5p in the prediction value for early diagnosis of SI-AKI was 0.895 (95% CI: 0.839-0.951, cutoff value: 0.780) and 0.838 (95% CI: 0.767-0.909, cutoff value: 0.775), respectively, and the AUC of them in the prediction value for clinical efficacy on the disease were 0.733 (95% CI: 0.645-0.820, cutoff value: 1.115) and 0.776 (95% CI: 0.698-0.855, cutoff value: 1.125), respectively. Serum miR-16-5p and mIR-4299 were negatively correlated with Scr, Cys-C, and KIM-1, separately.

Conclusion

Both miR-16-5p and mIR-4299 are promising factors for early diagnosis of SI-AKI and dynamic evaluation of the efficacy on it.

HSF1 Protects Sepsis-Induced Acute Lung Injury by Inhibiting NLRP3 Inflammasome Activation

As an important transcription factor, heat shock factor 1 (HSF1) plays an endogenous anti-inflammation role in the body and can alleviate multiple organ dysfunction caused by sepsis, which contributes to an uncontrolled inflammatory response. The NLRP3 inflammasome is a supramolecular complex that plays key roles in immune surveillance. Inflammation is accomplished by NLRP3 inflammasome activation, which leads to the proteolytic maturation of IL-1β and pyroptosis. However, whether HSF1 is involved in the activation of the NLRP3 inflammasome in septic acute lung injury (ALI) has not been reported. Here, we show that HSF1 suppresses NLRP3 inflammasome activation in transcriptional and post-translational modification levels. HSF1 can repress NLRP3 expression via inhibiting NF-κB phosphorylation. HSF1 can inhibit caspase-1 activation and IL-1β maturation via promoting NLRP3 ubiquitination. Our finding not only elucidates a novel mechanism for HSF1-mediated protection of septic ALI but also identifies new therapeutic targets for septic ALI and related diseases.

Frequency and mortality of sepsis and septic shock in China: a systematic review and meta-analysis

Background

Sepsis, a life-threatening organ dysfunction induced by infection, is a major public health problem. This study aimed to evaluate the frequency and mortality of sepsis, severe sepsis, and septic shock in China.

Methods

We Searched MEDLINE, Embase, PubMed, and Cochrane Library from 1 January 1992 to 1 June 2020 for studies that reported on the frequency and mortality of sepsis, severe sepsis, and septic shock conducted in China. Random effects models were performed to estimate the pooled frequency and mortality of sepsis, severe sepsis, and septic shock.

Results

Our search yielded 846 results, of which 29 studies were included in this review. The pooled frequency of sepsis was estimated at 33.6% (95% CI 25.9% to 41.3%, I² = 99.2%; p < 0.001), and the pooled mortality of sepsis, severe sepsis and septic shock were 29.0% (95% CI 25.3%–32.8%, I² = 92.1%; p = 0), 31.1% (95% CI 25.3% to 36.9%, I² = 85.8%; p < 0.001) and 37.3% (95% CI 28.6%–46.0%, I² = 93.5%; p < 0.001). There was significant heterogeneity between studies. With a small number of included studies and the changing definition of sepsis, trends in sepsis frequency and mortality were not sufficient for analysis. Epidemiological data on sepsis in the emergency department (ED) are severely lacking, and more research is urgently needed in this area is urgently needed.

Conclusions

Our findings indicated that the frequency and mortality of sepsis and septic shock in China were much higher than North America and Europe countries. Based on our results, an extremely high incidence and mortality of sepsis and septic shock in China's mainland requires more healthcare budget support. Epidemiological data on sepsis and septic shock in ED are severely lacking, and more research is urgently needed in this area.

Trial registration This systematic review was conducted according to the statement of the preferred reporting items for systematic review (PROSPERO CRD42021243325) and the meta-analysis protocols (PRISMA-P).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07543-8.

Association of annual hospital septic shock case volume and hospital mortality

BACKGROUND

The burden of sepsis remains high in China. The relationship between case volume and hospital mortality among patients with septic shock, the most severe complication of sepsis, is unknown in China.

METHODS

In this retrospective cohort study, we analyzed surveillance data from a national quality improvement program in intensive care units (ICUs) in China in 2020. Association between septic shock case volume and hospital mortality was analyzed using multivariate linear regression and restricted cubic splines.

RESULTS

We enrolled a total of 134,046 septic shock cases in ICUs from 1902 hospitals in China during 2020. In this septic shock cohort, the median septic shock volume per hospital was 33 cases (interquartile range 14-76 cases), 41.4% were female, and more than half of the patients were over 61 years old, with average hospital mortality of 21.2%. An increase in case volume was associated with improved survival among septic shock cases. In the linear regression model, the highest quartile of septic shock volume was associated with lower hospital mortality compared with the lowest quartile (β - 0.86; 95% CI - 0.98, - 0.74; p < 0.001). Similar differences were found in hospitals of respective geographic locations and hospital levels. With case volume modeled as a continuous variable in a restricted cubic spline, a lower volume threshold of 40 cases before which a substantial reduction of the hospital mortality rate was observed.

CONCLUSIONS

The findings suggest that hospitals with higher septic shock case volume have lower hospital mortality in China. Further research is needed to explain the mechanism of this volume-outcome relationship.

Alterations of the Gut Microbiome in Chinese Zhuang Ethnic Patients with Sepsis

Objectives

Sepsis is characterized as a dysregulated host immune response to infection and has been known to be closely associated with the gut microbiome. This study was aimed at investigating the gut microbial profiles of Zhuang ethnic patients with sepsis.

Method

Eleven Zhuang ethnic patients with sepsis and 20 healthy individuals (controls) were recruited at the Baise City People's Hospital, China. Their gut microbial community profiles were analyzed by 16S rRNA gene sequencing using the Illumina MiSeq system.

Results

The gut microbial community of patients with sepsis was significantly altered compared to that of the healthy individuals based on the results of principal coordinate analysis and microbial ecological networks. Additionally, significantly lower microbial alpha diversity was observed in patients with sepsis than in healthy individuals. In particular, the enrichment of Bilophila, Burkholderia, Corynebacterium, and Porphyromonas, along with the reduced abundance of a large number of short-chain fatty acid-producing microbes, including Roseburia, Bifidobacterium, Faecalibacterium, Coprococcus, Blautia, Clostridium, Ruminococcus, and Anaerostipe was observed in patients with sepsis compared to the control group. Moreover, patients with sepsis could be effectively classified based on the abundance of these bacteria using a support vector machine algorithm.

Conclusion

This study demonstrated significant differences in the gut microbiome between Zhuang ethnic patients with sepsis and healthy individuals. In the future, it is necessary to determine whether such alterations are the cause or consequence of sepsis.

Ascorbic acid and hydrocortisone synergistically inhibit septic organ injury via improving oxidative stress and inhibiting inflammation

BACKGROUND

The current study aimed to investigate the effect of the combination of ascorbic acid (AscA) and hydrocortisone (Hyd) on septic organ injury and its potential mechanism.

METHOD

Sepsis was induced in mice by a single intraperitoneal injection of lipopolysaccharides.

RESULTS

AscA and Hyd combined showed more effective protection of the injured liver and kidney in septic mice by decreasing ALT, AST, BUN and SCr and ameliorating pathological manifestations than Hyd or AscA alone. AscA showed a mild inhibitory effect on the secretion of proinflammatory cytokines (TNF-α, IL-1β and IL-6). However, Hyd showed a weak regulatory effect on septic oxidative stress markers (MDA, SOD and GSH-Px). However, the combination of AscA and Hyd showed a more powerful inhibitory effect on the septic inflammatory response and oxidative stress than Hyd or AscA alone by decreasing TNF-α, IL-1β and IL-6 and regulating MDA, SOD and GSH. In an in vitro study, cotreatment of RAW 264.7 macrophages with Hyd and AscA sharply reduced reactive oxygen species (ROS) generation and synergistically inhibited TNF-α, IL-1β and IL-6 secretion, which could be abolished by additional stimulation with the ROS donor 3-nitropropionic acid (3-NP). As expected, cotreatment of macrophages with Hyd and AscA synergistically inhibited the activation of p38 MAPK and p-p65, and the effect could be reversed by additional stimulation with 3-NP.

CONCLUSIONS

AscA and Hyd synergistically protect the kidney and liver from injury by inhibiting the inflammatory response and oxidative stress. The powerful inhibitory effects of AscA on oxidative stress contribute to the synergistic anti-inflammatory action.

Insight Into Regulatory T Cells in Sepsis-Associated Encephalopathy

Sepsis-associated encephalopathy (SAE) is a diffuse central nervous system (CNS) dysfunction during sepsis, and is associated with increased mortality and poor outcomes in septic patients. Despite the high incidence and clinical relevance, the exact mechanisms driving SAE pathogenesis are not yet fully understood, and no specific therapeutic strategies are available. Regulatory T cells (T_regs) have a role in SAE pathogenesis, thought to be related with alleviation of sepsis-induced hyper-inflammation and immune responses, promotion of T helper (Th) 2 cells functional shift, neuroinflammation resolution, improvement of the blood-brain barrier (BBB) function, among others. Moreover, in a clinical point of view, these cells have the potential value of improving neurological and psychiatric/mental symptoms in SAE patients. This review aims to provide a general overview of SAE from its initial clinical presentation to long-term cognitive impairment and summarizes the main features of its pathogenesis. Additionally, a detailed overview on the main mechanisms by which T_regs may impact SAE pathogenesis is given. Finally, and considering that T_regs may be a novel target for immunomodulatory intervention in SAE, different therapeutic options, aiming to boost peripheral and brain infiltration of T_regs, are discussed.

A Standardized Step-by-Step Approach for the Diagnosis and Treatment of Sepsis

Sepsis is the major culprit of death among critically ill patients who are hospitalized in intensive care units (ICUs). Although sepsis-related mortality is steadily declining year-by-year due to the continuous understanding of the pathophysiological mechanism on sepsis and improvement of the bundle treatment, sepsis-associated hospitalization is rising worldwide. Surviving Sepsis Campaign (SSC) guidelines are continuously updating, while their content is extremely complex and comprehensive for a precisely implementation in clinical practice. As a consequence, a standardized step-by-step approach for the diagnosis and treatment of sepsis is particularly important. In the present study, we proposed a standardized step-by-step approach for the diagnosis and treatment of sepsis using our daily clinical experience and the latest researches, which is close to clinical practice and is easy to implement. The proposed approach may assist clinicians to more effectively diagnose and treat septic patients and avoid the emergence of adverse clinical outcomes.

GRK2 regulates group 2 innate lymphoid cell mobilization in sepsis

BACKGROUND

Sepsis induces group 2 innate lymphoid cell (ILC2) expansion in the lung. However, the origin of these lung-recruited ILC2 and the mechanism of ILC2 expansion are unclear. This study aims to determine the origin of lung-recruited ILC2 and its underlying mechanism in sepsis.

METHODS

Sepsis was induced by cecal ligation and puncture (CLP) model in wild-type, IL-33-deficient and ST2-deficient mice. The frequency, cell number and C-X-C chemokine receptor 4 (CXCR4) expression of ILC2 in bone marrow (BM), blood and lung were measured by flow cytometry. In the in vitro studies, purified ILC2 progenitor (ILC2p) were challenged with IL-33 or G protein-coupled receptor kinase 2 (GRK2) inhibitor, the CXCR4 expression and GRK2 activity were detected by confocal microscopy or flow cytometry.

RESULTS

We show that IL-33 acts through its receptor, ST2, on BM ILC2p to induce GRK2 expression and subsequent downregulation of cell surface expression of CXCR4, which results in decreasing retention of ILC2p in the BM and promoting expansion of ILC2 in the lung. Importantly, we demonstrate that reduced IL-33 level in aging mice contributes to impaired ILC2 mobilization from BM and accumulation in the lung following sepsis.

CONCLUSION

This study identifies a novel pathway in regulating ILC2p mobilization and expansion during sepsis and indicates BM as the main source of ILC2 in the lung following sepsis.

Regulatory T Cells: Angels or Demons in the Pathophysiology of Sepsis?

Sepsis is a syndrome characterized by life-threatening organ dysfunction caused by the dysregulated host response to an infection. Sepsis, especially septic shock and multiple organ dysfunction is a medical emergency associated with high morbidity, high mortality, and prolonged after-effects. Over the past 20 years, regulatory T cells (Tregs) have been a key topic of focus in all stages of sepsis research. Tregs play a controversial role in sepsis based on their heterogeneous characteristics, complex organ/tissue-specific patterns in the host, the multi-dimensional heterogeneous syndrome of sepsis, the different types of pathogenic microbiology, and even different types of laboratory research models and clinical research methods. In the context of sepsis, Tregs may be considered both angels and demons. We propose that the symptoms and signs of sepsis can be attenuated by regulating Tregs. This review summarizes the controversial roles and Treg checkpoints in sepsis.