Biomarkers of sepsis: time for a reappraisal

LncRNA GAS5 downregulates NLRP3 inflammasome activation-mediated pyroptosis in sepsis-induced myocardial injury by targeting SIRT3/AMPKα

An increasing body of studies has demonstrated the significance of long non-coding RNA (lncRNA) growth arrest specific 5 (GAS5) in inflammation and myocardial injury in septic shock. This research aims to determine whether GAS5 contributes to the pathological development of sepsis-induced cardiac damage and NLRP3 inflammasome-mediated myocardial cell pyroptosis. Cecal ligation and puncture (CLP) surgery was used to cause septic shock in C57BL/6 wild-type mice. After CLP, inflammatory, pyroptosis parameters of myocardial tissue, survival rate, and Murine Sepsis Score (MSS) were assessed to evaluate the involvement of GAS5 in the mouse myocardial depression. To investigate GAS5's function in lipopolysaccharide (LPS) induced myocardial cell pyroptosis, gain- and loss-of-function experiments were conducted in vitro on HL-1 cells. Our findings indicated that CLP dramatically reduced survival rates, MSS, SIRT3 and p-AMPK expression, and activated the Nuclear factor-κB (NF-κB) pathway and NLRP3 inflammasome-mediated pyroptosis. The NF-κB and pyroptosis pathways were greatly elevated while SIRT3/p-AMPKα was dramatically decreased as a result of GAS5 being downregulated. Meanwhile, the regulatory effect could be suppressed by SIRT3 and AMPKα activator. Our observations supported the idea that GAS5 has a crucial protective impact against myocardial inflammation and pyroptosis in sepsis.

Interdisciplinary perspectives on computed tomography in sepsis: survey among medical doctors at a large university medical center

OBJECTIVES

This study aims to describe physicians' perspectives on the use of computed tomography (CT) in patients with sepsis.

METHODS

In January 2022, physicians of a large European university medical center were surveyed using a web-based questionnaire asking about their views on the role of CT in sepsis. A total of 371 questionnaires met the inclusion criteria and were analyzed using work experience, workplace, and medical specialty of physicians as variables. Chi-square tests were performed.

RESULTS

Physicians considered the ability to detect an unknown focus as the greatest benefit of CT scans in sepsis (70.9%, n = 263/371). Two clinical criteria - "signs of decreased vigilance" (89.2%, n = 331/371) and "increased catecholamine demand" (84.7%, n = 314/371) - were considered highly relevant for a CT request. Elevated procalcitonin (82.7%, n = 307/371) and lactate levels (83.6%, n = 310/371) were consistently found to be critical laboratory values to request a CT. As long as there is evidence of infection in one organ region, most physicians (42.6%, n = 158/371) would order a CT scan based on clinical assessment. Combined examination of the chest, abdomen, and pelvis was favored (34.8%, n = 129/371) in cases without clinical clues of an infection source. A time window of ≥ 1-6 h was preferred for both CT examinations (53.9%, n = 200/371) and CT-guided interventions (59.3%, n = 220/371) in patients with sepsis.

CONCLUSION

Despite much consensus, there are significant differences in attitudes towards the use of CT in septic patients among physicians from different workplaces and medical specialties. Knowledge of these perspectives may improve patient management and interprofessional communication.

KEY POINTS

Despite interdisciplinary consensus on the use of CT in sepsis, statistically significant differences in the responses are apparent among physicians from different workplaces and medical specialties. The detection of a previously unknown source of infection and the ability to plan interventions and/or surgery based on CT findings are considered key advantages of CT in septic patients. Timing of CT reflects the requirements of specific disciplines.

Analysis of Protein Biomarkers From Hospitalized COVID-19 Patients Reveals Severity-Specific Signatures and Two Distinct Latent Profiles With Differential Responses to Corticosteroids

OBJECTIVES

To identify and validate novel COVID-19 subphenotypes with potential heterogenous treatment effects (HTEs) using electronic health record (EHR) data and 33 unique biomarkers.

DESIGN

Retrospective cohort study of adults presenting for acute care, with analysis of biomarkers from residual blood collected during routine clinical care. Latent profile analysis (LPA) of biomarker and EHR data identified subphenotypes of COVID-19 inpatients, which were validated using a separate cohort of patients. HTE for glucocorticoid use among subphenotypes was evaluated using both an adjusted logistic regression model and propensity matching analysis for in-hospital mortality.

SETTING

Emergency departments from four medical centers.

PATIENTS

Patients diagnosed with COVID-19 based on International Classification of Diseases , 10th Revision codes and laboratory test results.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Biomarker levels generally paralleled illness severity, with higher levels among more severely ill patients. LPA of 522 COVID-19 inpatients from three sites identified two profiles: profile 1 ( n = 332), with higher levels of albumin and bicarbonate, and profile 2 ( n = 190), with higher inflammatory markers. Profile 2 patients had higher median length of stay (7.4 vs 4.1 d; p < 0.001) and in-hospital mortality compared with profile 1 patients (25.8% vs 4.8%; p < 0.001). These were validated in a separate, single-site cohort ( n = 192), which demonstrated similar outcome differences. HTE was observed ( p = 0.03), with glucocorticoid treatment associated with increased mortality for profile 1 patients (odds ratio = 4.54).

CONCLUSIONS

In this multicenter study combining EHR data with research biomarker analysis of patients with COVID-19, we identified novel profiles with divergent clinical outcomes and differential treatment responses.

The Clinical Performance of Cell Population Data for Diagnosis of Bloodstream Infection in Cancer Patients

Background Bloodstream infection (BSI) induces a change in the number and morphology of blood cells. In this study, we compared cell population data (CPD) parameters between cancer patients with or without BSI to determine whether these parameters could serve as biomarkers of BSI. Methods Between April and June 2021, 43 BSI-negative and 22 BSI-positive cancer patients were enrolled in this study. We compared 18 CPD parameters and biomarkers between cancer patients with BSI-positive and BSI-negative. Results There were significant differences in the levels of several CPD parameters, including MO-WZ (p=0.040), MO-X (p<0.01), MO-Y (p=0.012), NE-SFL (p<0.01), and NE-WX (p=0.037), but not C-reactive protein (p=0.347) and procalcitonin (p=0.237) between BSI-positive and BSI-negative patients. The areas under the receiver-operating characteristic curves (AUCs) were above 0.7 for MO-X (0.762; 95% confidence intervals (CI): 0.624-0.901), NE-SFL (0.766; 95% CI: 0.625-0.880). And LY-WY (p=0.024) showed a significant difference between gram-negative and gram-positive BSI patients with high AUC (0.883; 95% CI: 0.703-1). Conclusion CPD parameters (MO-X and NE-SFL) provide additional information for discriminating between BSI-negative and BSI-positive BSI. And LY-WY provides useful information for discriminating between cancer patients with gram-negative BSI and gram-positive BSI.

Study of Phospholipase A2 Levels and Its Comparison With Procalcitonin Levels in Patients With Sepsis Admitted in a Tertiary Care Hospital, Karnataka, India

INTRODUCTION

Sepsis is a complicated host response to infection involving organ failure which ultimately causes death of the host. Procalcitonin (PCT) is an effective marker used to diagnose sepsis but until now, there has been no ideal marker for sepsis. Phospholipase A2 (PLA2) also increases infections; however, only a few studies have assessed its capacity as a biomarker to diagnose sepsis. Thus, we aimed to examine PLA2 and compare its diagnostic capacity and accuracy with PCT as a biomarker of sepsis.

MATERIAL AND METHODS

Our study was a hospital-oriented cross-sectional study. Our study group included 80 patients of both sexes older than 18 years, meeting the quick sequential organ failure assessment (qSOFA) or systemic inflammatory response syndrome (SIRS) criteria of ≥2, hospitalized in a tertiary care hospital in Karnataka, India from January 2021 to December 2021. Out of them, 59 were found to have sepsis. Samples of all the patients were evaluated for relevant parameters, and data were statistically analyzed using SPSS v21 running on Windows 10. The statistical significance was set at p-value <0.05.

RESULTS

The mean PCT and PLA2 were significantly raised in sepsis patients compared to non-sepsis patients. Out of 59 septic patients, 45.76% had positive blood cultures, and 16.95% had positive urine culture reports. In blood cultures, the most common Gram-positive organism found was Staphylococcus, and the most common Gram-negative organism was Enterobacter. In urine cultures, Escherichia coli was the most common species. PLA2 was significantly higher in patients with bacterial etiology and Gram-positive cultures. The diagnostic capability, sensitivity, specificity, and accuracy of PLA2 were demonstrably higher than those of PCT.

CONCLUSION

Our study proves that PLA2 is a much better and more efficient biomarker in sepsis than PCT. The diagnostic capacity and accuracy of PLA2 clearly surpass PCT, so using PLA2 in sepsis as a biomarker can help clinicians in deciding on timely and appropriate management to speed the recovery of patients.

Predicting the prognosis in patients with sepsis by an endoplasmic reticulum stress gene signature

BACKGROUND

Prognostic stratification of patients with sepsis is important for the development of individualized treatment strategies. Endoplasmic reticulum stress (ERS) plays a key role in sepsis. This study aimed to identify a set of genes related to ER stress to construct a predictive model for the prognosis of sepsis.

METHODS

The transcriptomic and clinical data of 479 sepsis patients were obtained from GSE65682 and divided into a training set (n=288) and a validation set (n=191) at a ratio of 3:2. The external test set was GSE95233 (n=51). LASSO and Cox regression analyses were performed to establish a signature to predict the prognosis of patients with sepsis. Moreover, we developed a nomogram that included the risk signature and clinical features to predict survival probability.

RESULTS

A prognostic signature was constructed with ten endoplasmic reticulum related genes (ADRB2, DHCR7, GABARAPL2, MAOA, MPO, PDZD8, QDPR, SCAP, TFRC, and TLR4) in the training set, which significantly divided patients with sepsis into high- and low-risk groups in terms of survival. This signature was validated using validation and external test sets. A nomogram based on the risk signature was constructed to quantitatively predict the prognosis of patients with sepsis.

CONCLUSIONS

We constructed an ERS signature as a novel prognostic marker for predicting survival in sepsis patients, which could be used to develop novel biomarkers for the diagnosis, treatment, and prognosis of sepsis and to provide new ideas and prospects for future clinical research.

Anti-inflammatory and antioxidant properties of betaine protect against sepsis-induced acute lung injury: CT and histological evidence

The aim of this research was to determine the anti-inflammatory effect of betaine on sepsis-induced acute respiratory distress syndrome (ARDS) in rats through histopathological examination, radiologic imaging, and biochemical analysis. Eight rats were included in the control group, and no procedure was performed. Feces intraperitoneal procedure (FIP) was performed on 24 rats to create a sepsis-induced ARDS model. These rats were separated into three groups as follows: FIP alone (sepsis group, n=8), FIP + saline (1 mL/kg, placebo group, n=8), and FIP + betaine (500 mg/kg, n=8). Computed tomography (CT) was performed after FIP, and the Hounsfield units (HU) value of the lungs was measured. The plasma levels of tumor necrosis factor (TNF)-α, interleukin-1β (IL-1β), IL-6, C-reactive protein, malondialdehyde (MDA), and lactic acid (LA) were determined, and arterial oxygen pressure (PaO2) and arterial CO2 pressure (PaCO2) were measured from an arterial blood sample. Histopathology was used to evaluate lung damage. This study completed all histopathological and biochemical evaluations in 3 months. All evaluated biomarkers were decreased in the FIP + betaine group compared to FIP + saline and FIP alone (all P<0.05). Also, the parenchymal density of the rat lung on CT and histopathological scores were increased in FIP + saline and FIP alone compared to control and these findings were reversed by betaine treatment (all P<0.05). Our study demonstrated that betaine suppressed the inflammation and ameliorated acute lung injury in a rat model of sepsis.

Screening tools for sepsis identification in paramedicine and other emergency contexts: a rapid systematic review

BACKGROUND

Sepsis is a life-threatening condition that contributes significantly to protracted hospitalisations globally. The unique positioning of paramedics and other emergency care cadres in emergency contexts enable the prospect of early identification and management of sepsis, however, a standardised screening tool still does not exist in the emergency setting. The objective of this review was to identify and recommend the most clinically ideal sepsis screening tool for emergency contexts such as emergency departments and out-of-hospital emergency contexts.

METHODS

A rapid review of five databases (Medline, Embase, the Cochrane Library, CINAHL, and ProQuest Central) was undertaken, with searches performed on February 10, 2022. Covidence software was used by two authors for initial screening, and full text review was undertaken independently by each reviewer, with conflicts resolved by consensus-finding and a mediator. Systematic reviews, meta-analyses, randomised controlled trials, and prospective observational studies were eligible for inclusion. Data extraction used an a priori template and focused on sensitivity and specificity, with ROBINS-I and ROBIS bias assessment tools employed to assess risk of bias in included studies. Study details and key findings were summarised in tables. The a priori review protocol was registered on Open Science Framework ( https://doi.org/10.17605/OSF.IO/3XQ5T ).

RESULTS

The literature search identified 362 results. After review, 18 studies met the inclusion criteria and were included for analysis. There were five systematic reviews, with three including meta-analysis, eleven prospective observational studies, one randomised controlled trial, and one validation study.

CONCLUSIONS

The review recognised that a paucity of evidence exists surrounding standardised sepsis screening tools in the emergency context. The use of a sepsis screening tool in the emergency environment may be prudent, however there is currently insufficient evidence to recommend a single screening tool for this context. A combination of the qSOFA and SIRS may be employed to avoid 'practice paralysis' in the interim. The authors acknowledge the inherent potential for publication and selection bias within the review due to the inclusion criteria.

Organotypic heterogeneity in microvascular endothelial cell responses in sepsis-a molecular treasure trove and pharmacological Gordian knot

In the last decades, it has become evident that endothelial cells (ECs) in the microvasculature play an important role in the pathophysiology of sepsis-associated multiple organ dysfunction syndrome (MODS). Studies on how ECs orchestrate leukocyte recruitment, control microvascular integrity and permeability, and regulate the haemostatic balance have provided a wealth of knowledge and potential molecular targets that could be considered for pharmacological intervention in sepsis. Yet, this information has not been translated into effective treatments. As MODS affects specific vascular beds, (organotypic) endothelial heterogeneity may be an important contributing factor to this lack of success. On the other hand, given the involvement of ECs in sepsis, this heterogeneity could also be leveraged for therapeutic gain to target specific sites of the vasculature given its full accessibility to drugs. In this review, we describe current knowledge that defines heterogeneity of organ-specific microvascular ECs at the molecular level and elaborate on studies that have reported EC responses across organ systems in sepsis patients and animal models of sepsis. We discuss hypothesis-driven, single-molecule studies that have formed the basis of our understanding of endothelial cell engagement in sepsis pathophysiology, and include recent studies employing high-throughput technologies. The latter deliver comprehensive data sets to describe molecular signatures for organotypic ECs that could lead to new hypotheses and form the foundation for rational pharmacological intervention and biomarker panel development. Particularly results from single cell RNA sequencing and spatial transcriptomics studies are eagerly awaited as they are expected to unveil the full spatiotemporal signature of EC responses to sepsis. With increasing awareness of the existence of distinct sepsis subphenotypes, and the need to develop new drug regimen and companion diagnostics, a better understanding of the molecular pathways exploited by ECs in sepsis pathophysiology will be a cornerstone to halt the detrimental processes that lead to MODS.

Analysis of 4-Hydroxyphenyllactic Acid and Other Diagnostically Important Metabolites of α-Amino Acids in Human Blood Serum Using a Validated and Sensitive Ultra-High-Pressure Liquid Chromatography-Tandem Mass Spectrometry Method

The profile of and dynamic concentration changes in tyrosine, phenylalanine, and tryptophan metabolites in blood are of great interest since they could be considered potential biomarkers of different disorders. Some aromatic metabolites, such as 4-hydroxyphenyllactic, 4-hydroxyphenylacetic, phenyllactic, and 4-hydroxybenzoic acids have previously demonstrated their diagnostic significance in critically ill patients and patients with post-COVID-19 syndrome. In this study, a sensitive method, including serum protein precipitation with methanol and ultra-high-pressure liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) detection, was developed and validated for six phenyl- and five indole-containing acids in human serum. The liquid-liquid extraction was also examined, but it demonstrated unsatisfactory results based on analyte recoveries and the matrix effect. However, the recoveries for all analytes reached 100% and matrix effects were not observed using protein precipitation. This made it possible to use deionized water as a blank matrix. The lower limits of quantitation (LLOQs) were from 0.02 to 0.25 μmol/L. The validated method was used for the analysis of serum samples of healthy volunteers (n = 48) to reveal the reference values of the target analytes. The concentrations of the most clinically significant metabolite 4-hydroxyphenyllactic acid, which were revealed using UPLC-MS/MS and a previously developed gas chromatography-mass spectrometry method, were completely comparable. The proposed UPLC-MS/MS protocol can be used in the routine clinical practice of medical centers.

Commensal Bacteria Impact on Intestinal Toll-like Receptor Signaling in Salmonella-Challenged Gnotobiotic Piglets

Gnotobiotic (GN) animals with simple and defined microbiota can help to elucidate host-pathogen interferences. Hysterectomy-derived germ-free (GF) minipigs were associated at 4 and 24 h post-hysterectomy with porcine commensal mucinolytic Bifidobacterium boum RP36 (RP36) strain or non-mucinolytic strain RP37 (RP37) or at 4 h post-hysterectomy with Lactobacillus amylovorus (LA). One-week-old GN minipigs were infected with Salmonella Typhimurium LT2 strain (LT2). We monitored histological changes in the ileum, mRNA expression of Toll-like receptors (TLRs) 2, 4, and 9 and their related molecules lipopolysaccharide-binding protein (LBP), coreceptors MD-2 and CD14, adaptor proteins MyD88 and TRIF, and receptor for advanced glycation end products (RAGE) in the ileum and colon. LT2 significantly induced expression of TLR2, TLR4, MyD88, LBP, MD-2, and CD14 in the ileum and TLR4, MyD88, TRIF, LBP, and CD14 in the colon. The LT2 infection also significantly increased plasmatic levels of inflammatory markers interleukin (IL)-6 and IL-12/23p40. The previous colonization with RP37 alleviated damage of the ileum caused by the Salmonella infection, and RP37 and LA downregulated plasmatic levels of IL-6. A defined oligo-microbiota composed of bacterial species with selected properties should probably be more effective in downregulating inflammatory response than single bacteria.

Soluble urokinase plasminogen activator receptor and procalcitonin for risk stratification in patients with a suspected infection in the emergency department: a prospective cohort study

BACKGROUND AND IMPORTANCE

Early identification of patients at risk of clinical deterioration may improve prognosis of infected patients in the emergency department (ED). Combining clinical scoring systems with biomarkers may result in a more accurate prediction of mortality than a clinical scoring system or biomarker alone.

OBJECTIVE

The objective of this study is to investigate the performance of the combination of National Early Warning Score-2 (NEWS2) and quick Sequential Organ Failure Assessment (qSOFA) score with soluble urokinase plasminogen activator receptor (suPAR) and procalcitonin to predict 30-day mortality in patients with a suspected infection in the ED.

DESIGN, SETTINGS AND PARTICIPANTS

This was a single-center prospective observational study, conducted in the Netherlands. Patients with suspected infection in the ED were included in this study and followed-up for 30 days. The primary outcome of this study was all cause 30-day mortality. The association between suPAR and procalcitonin with mortality was assessed in subgroups of patients with low and high qSOFA (<1 and ≥1) and low and high NEWS2 (<7 and ≥7).

MAIN RESULTS

Between March 2019 and December 2020, 958 patients were included. A total of 43 (4.5%) patients died within 30 days after ED visit. A suPAR ≥ 6 ng/ml was associated with an increased mortality risk: 5.5 vs. 0.9% ( P  < 0.01) in patients with qSOFA = 0 and 10.7 vs. 2.1% ( P  = 0.02) in patients with qSOFA ≥ 1. There was also an association between procalcitonin ≥0.25 ng/ml and mortality: 5.5 vs. 1.9% ( P  = 0.02) for qSOFA = 0 and 11.9 vs. 4.1% ( P  = 0.03) for qSOFA ≥ 1. Similar associations were found within patients with a NEWS < 7 (5.9 vs. 1.2% for suPAR and 7.0 vs. 1.7% for procalcitonin, P  < 0.001).

CONCLUSION

In this prospective cohort study, suPAR and procalcitonin were associated with increased mortality in patients with either a low or high qSOFA and patients with low NEWS2.

C-Reactive Protein: Pathophysiology, Diagnosis, False Test Results and a Novel Diagnostic Algorithm for Clinicians

The current literature provides a body of evidence on C-Reactive Protein (CRP) and its potential role in inflammation. However, most pieces of evidence are sparse and controversial. This critical state-of-the-art monography provides all the crucial data on the potential biochemical properties of the protein, along with further evidence on its potential pathobiology, both for its pentameric and monomeric forms, including information for its ligands as well as the possible function of autoantibodies against the protein. Furthermore, the current evidence on its potential utility as a biomarker of various diseases is presented, of all cardiovascular, respiratory, hepatobiliary, gastrointestinal, pancreatic, renal, gynecological, andrological, dental, oral, otorhinolaryngological, ophthalmological, dermatological, musculoskeletal, neurological, mental, splenic, thyroid conditions, as well as infections, autoimmune-supposed conditions and neoplasms, including other possible factors that have been linked with elevated concentrations of that protein. Moreover, data on molecular diagnostics on CRP are discussed, and possible etiologies of false test results are highlighted. Additionally, this review evaluates all current pieces of evidence on CRP and systemic inflammation, and highlights future goals. Finally, a novel diagnostic algorithm to carefully assess the CRP level for a precise diagnosis of a medical condition is illustrated.

Prognostic biomarkers for sepsis mortality based on the literature and LC-MS-based metabolomics of sepsis patients

OBJECTIVES

The management of sepsis, a potentially lethal overreaction to infection, is limited by the lack of prognostic tools to guide its treatment. Our aim is to identify a novel metabolic biomarker panel for predicting sepsis mortality based on a literature review and liquid chromatography-mass spectrometry (LC-MS)-based metabolomics.

METHODS

In the literature, we found metabolomics biomarkers reported to predict sepsis mortality. We determined the classifications, reported frequency, and KEGG pathway enrichment of these markers. Using serum samples from 20 sepsis survivors and 20 non-survivors within 28 days after admission to the intensive care unit (ICU), we performed LC-MS-based metabolomics. Based on the literature review and metabolomics, a prognostic biomarker panel for sepsis was identified and its area under the curve (AUC) values was assessed.

RESULTS

Kynurenate, caffeine, and lysoPC 22:4 were selected as a prognostic biomarker panel for sepsis. The panel had an area under the curve (AUC) of 0.885 (95% CI, 0.694-1) evaluated by linear support vector machine (SVM) and 0.849 (0.699-1) by random forest (RF), which was higher than that of the Sequential Organ Failure Assessment (SOFA). A combination of kynurenate, caffeine, and lysoPC 22:4 and SOFA provided the best discriminating performance, with AUCs of 0.961 (0.878-1) for SVM and 0.916 (0.774-1) for RF.

CONCLUSIONS

The prognostic biomarker panel consisting of kynurenate, caffeine, and lysoPC 22:4 may aid in the identification of sepsis patients at a high risk of death, leading to personalized therapy in clinical practice that will improve sepsis survival.

A generalizable and interpretable model for mortality risk stratification of sepsis patients in intensive care unit

PURPOSE

This study aimed to construct a mortality model for the risk stratification of intensive care unit (ICU) patients with sepsis by applying a machine learning algorithm.

METHODS

Adult patients who were diagnosed with sepsis during admission to ICU were extracted from MIMIC-III, MIMIC-IV, eICU, and Zigong databases. MIMIC-III was used for model development and internal validation. The other three databases were used for external validation. Our proposed model was developed based on the Extreme Gradient Boosting (XGBoost) algorithm. The generalizability, discrimination, and validation of our model were evaluated. The Shapley Additive Explanation values were used to interpret our model and analyze the contribution of individual features.

RESULTS

A total of 16,741, 15,532, 22,617, and 1,198 sepsis patients were extracted from the MIMIC-III, MIMIC-IV, eICU, and Zigong databases, respectively. The proposed model had an area under the receiver operating characteristic curve (AUROC) of 0.84 in the internal validation, which outperformed all the traditional scoring systems. In the external validations, the AUROC was 0.87 in the MIMIC-IV database, better than all the traditional scoring systems; the AUROC was 0.83 in the eICU database, higher than the Simplified Acute Physiology Score III and Sequential Organ Failure Assessment (SOFA),equal to 0.83 of the Acute Physiology and Chronic Health Evaluation IV (APACHE-IV), and the AUROC was 0.68 in the Zigong database, higher than those from the systemic inflammatory response syndrome and SOFA. Furthermore, the proposed model showed the best discriminatory and calibrated capabilities and had the best net benefit in each validation.

CONCLUSIONS

The proposed algorithm based on XGBoost and SHAP-value feature selection had high performance in predicting the mortality of sepsis patients within 24 h of ICU admission.

Effects of C-reactive protein trajectories of critically ill patients with sepsis on in-hospital mortality rate

Sepsis, a life-threatening condition caused by an inflammatory response to systemic infection, results in a significant social burden and healthcare costs. This study aimed to investigate the relationship between the C-reactive protein (CRP) trajectories of patients with sepsis in the intensive care unit (ICU) and the in-hospital mortality rate. We reviewed 1464 patients with sepsis treated in the ICU of Dongyang People's Hospital from 2010 to 2020 and used latent growth mixture modeling to divide the patients into four classes according to CRP trajectory (intermediate, gradually increasing, persistently high, and persistently low CRP levels). We found that patients with intermediate and persistently high CRP levels had the lowest (18.1%) and highest (32.6%) in-hospital mortality rates, respectively. Multiple logistic regression analysis showed that patients with persistently high (odds ratio [OR] = 2.19, 95% confidence interval [CI] = 1.55-3.11) and persistently low (OR = 1.41, 95% CI = 1.03-1.94) CRP levels had a higher risk of in-hospital mortality than patients with intermediate CRP levels. In conclusion, in-hospital mortality rates among patients with sepsis differ according to the CRP trajectory, with patients with intermediate CRP levels having the lowest mortality rate. Further research on the underlying mechanisms is warranted.

Predicting sepsis using a combination of clinical information and molecular immune markers sampled in the ambulance

Sepsis is a time dependent condition. Screening tools based on clinical parameters have been shown to increase the identification of sepsis. The aim of current study was to evaluate the additional predictive value of immunological molecular markers to our previously developed prehospital screening tools. This is a prospective cohort study of 551 adult patients with suspected infection in the ambulance setting of Stockholm, Sweden between 2017 and 2018. Initially, 74 molecules and 15 genes related to inflammation were evaluated in a screening cohort of 46 patients with outcome sepsis and 50 patients with outcome infection no sepsis. Next, 12 selected molecules, as potentially synergistic predictors, were evaluated in combination with our previously developed screening tools based on clinical parameters in a prediction cohort (n = 455). Seven different algorithms with nested cross-validation were used in the machine learning of the prediction models. Model performances were compared using posterior distributions of average area under the receiver operating characteristic (ROC) curve (AUC) and difference in AUCs. Model variable importance was assessed by permutation of variable values, scoring loss of classification as metric and with model-specific weights when applicable. When comparing the screening tools with and without added molecular variables, and their interactions, the molecules per se did not increase the predictive values. Prediction models based on the molecular variables alone showed a performance in terms of AUCs between 0.65 and 0.70. Among the molecular variables, IL-1Ra, IL-17A, CCL19, CX3CL1 and TNF were significantly higher in septic patients compared to the infection non-sepsis group. Combing immunological molecular markers with clinical parameters did not increase the predictive values of the screening tools, most likely due to the high multicollinearity of temperature and some of the markers. A group of sepsis patients was consistently miss-classified in our prediction models, due to milder symptoms as well as lower expression levels of the investigated immune mediators. This indicates a need of stratifying septic patients with a priori knowledge of certain clinical and molecular parameters in order to improve prediction for early sepsis diagnosis.Trial registration: NCT03249597. Registered 15 August 2017.

The antimicrobial peptide chensinin-1b alleviates the inflammatory response by targeting the TLR4/NF-κB signaling pathway and inhibits Pseudomonas aeruginosa infection and LPS-mediated sepsis

Excessive inflammatory responses are a major contributor to the high mortality associated with sepsis, a prevalent global complication. Therefore, the potential therapeutic strategy for sepsis involves targeting macrophages and reducing proinflammatory cytokine release. Chensinin-1b, an analog of the natural antimicrobial peptide derived from Rana chensinensis skin secretion, exhibits broad-spectrum antibacterial activity and adopts a random coil conformation in both PBS and membrane solution. By efficiently neutralizing LPS, chensinin-1b holds promise in alleviating LPS-induced inflammatory responses. In this study, we established a mouse septic shock model by exposing mice to multiple-drug-resistant Pseudomonas aeruginosa, as well as an endotoxin-mediated sepsis model induced by LPS. Administering chensinin-1b significantly prolonged the survival of the experimental mice, concurrently mitigating inflammatory responses and reducing organ damage. Additionally, we investigated the anti-inflammatory mechanism of chensinin-1b using a constructed LPS-induced mouse macrophage RAW264.7 inflammatory model. Our findings demonstrated that chensinin-1b effectively mitigated the excessive activation of the TLR4/NF-κB signaling pathway by directly neutralizing extracellular LPS, thus ameliorating the inflammatory response. Moreover, upon blocking the TLR4 signaling pathway, chensinin-1b further reduced the release of proinflammatory cytokines induced by LPS, indicating alternative modes of regulation. Notably, chensinin-1b rapidly entered RAW264.7 cells within 30 min via endocytosis, diffusing into the cytoplasm while retaining its anti-inflammatory properties intracellularly. Although further investigations are warranted to comprehensively elucidate the intracellular anti-inflammatory mechanism of chensinin-1b, our findings substantiate its possession of anti-inflammatory properties both intracellularly and extracellularly. Thus, chensinin-1b emerges as a promising candidate for mitigating excessive inflammatory responses associated with sepsis.

Single-cell RNA sequencing deciphers the mechanism of sepsis-induced liver injury and the therapeutic effects of artesunate

Liver, as an immune and detoxification organ, represents an important line of defense against bacteria and infection and a vulnerable organ that is easily injured during sepsis. Artesunate (ART) is an anti-malaria agent, that also exhibits broad pharmacological activities including anti-inflammatory, immune-regulation and liver protection. In this study, we investigated the cellular responses in liver to sepsis infection and ART hepatic-protective mechanisms against sepsis. Cecal ligation and puncture (CLP)-induced sepsis model was established in mice. The mice were administered ART (10 mg/kg, i.p.) at 4 h, and sacrificed at 12 h after the surgery. Liver samples were collected for preparing single-cell RNA transcriptome sequencing (scRNA-seq). The scRNA-seq analysis revealed that sepsis-induced a dramatic reduction of hepatic endothelial cells, especially the subtypes characterized with proliferation and differentiation. Macrophages were recruited during sepsis and released inflammatory cytokines (Tnf, Il1b, Il6), chemokines (Ccl6, Cd14), and transcription factor (Nfkb1), resulting in liver inflammatory responses. Massive apoptosis of lymphocytes and abnormal recruitment of neutrophils caused immune dysfunction. ART treatment significantly improved the survival of CLP mice within 96 h, and partially relieved or reversed the above-mentioned pathological features, mitigating the impact of sepsis on liver injury, inflammation, and dysfunction. This study provides comprehensive fundamental proof for the liver protective efficacy of ART against sepsis infection, which would potentially contribute to its clinical translation for sepsis therapy. Single cell transcriptome reveals the changes of various hepatocyte subtypes of CLP-induced liver injury and the potential pharmacological effects of artesunate on sepsis.

Detection of Inflammatory Biomarkers Among Patients with Sepsis of Gram-Negative Bacteria: A Cross-Sectional Study

Background

Sepsis is a highly mixed ailment that affects patients with numerous conditions of infectious sources and can lead to multi-organ failure with dysregulated host immune response.

Objective

To determine inflammatory biomarkers in patients with sepsis caused by Gram-negative bacteria and compare their role in the early detection of sepsis.

Methods

This cross-sectional study was conducted on patients with sepsis admitted to the intensive care unit at different hospitals in Sulaimaniyah, Iraq, from May to December 2021. Patients (n=147) were enrolled in this study according to the primary diagnosis of sepsis by Sequential Organ Failure Assessment scores. Blood samples were taken from patients to investigate white blood cells, inflammatory biomarkers (pentraxin-3, procalcitonin, adrenomedullin, lipopolysaccharide binding protein, interleukin-17A, lactate dehydrogenase, and C-creative protein), blood culture, antibiotic susceptibility test, and coagulation biomarkers (Prothrombin time, activated partial thromboplastin time, and international normalized ratio). Then, isolated Gram-negative bacteria were tested for extended-spectrum β-lactamase enzymes production by screening and combined disc tests.

Results

A total of 51.7% samples were blood culture positive for different Gram-negative bacteria, and P. aeruginosa (51.95%) was a more isolated bacterium. Both males and females were affected by sepsis in a ratio of 1.23:1 with different age groups. Extended-spectrum β-lactamase was estimated to be 77.2% by antibiotic profile, and the rate decreased using two double-disc synergy tests. This was confirmed by combined disc test at a rate of 41.35%. The most prevalent biomarkers were procalcitonin (88.16%), adrenomedullin (84.21%), pentraxin-3 (22.37%), and lipopolysaccharide binding protein (11.84%).

Conclusion

Sepsis is a life-threatening condition that can be diagnosed early by several blood biomarkers such as procalcitonin, adrenomedullin, and pentraxin-3 combined with a standard blood culture technique to improve the patient outcome.

Research Progress of DcR3 in the Diagnosis and Treatment of Sepsis

Decoy receptor 3 (DcR3), a soluble glycosylated protein in the tumor necrosis factor receptor superfamily, plays a role in tumor and inflammatory diseases. Sepsis is a life-threatening organ dysfunction caused by the dysregulation of the response to infection. Currently, no specific drug that can alleviate or even cure sepsis in a comprehensive and multi-level manner has been found. DcR3 is closely related to sepsis and considerably upregulated in the serum of those patients, and its upregulation is positively correlated with the severity of sepsis and can be a potential biomarker for diagnosis. DcR3 alone or in combination with other markers has shown promising results in the early diagnosis of sepsis. Furthermore, DcR3 is a multipotent immunomodulator that can bind FasL, LIGHT, and TL1A through decoy action, and block downstream apoptosis and inflammatory signaling. It also regulates T-cell and macrophage differentiation and modulates immune status through non-decoy action; therefore, DcR3 could be a potential drug for the treatment of sepsis. The application of DcR3 in the treatment of a mouse model of sepsis also achieved good efficacy. Here, we introduce and discuss the progress in, and suggest novel ideas for, research regarding DcR3 in the diagnosis and treatment of sepsis.

Severe Acute Bronchial Asthma with Sepsis: Determining the Status of Biomarkers in the Diagnosis of the Disease

Bronchial asthma is a widely prevalent illness that substantially impacts an individual's health standard worldwide and has a significant financial impact on society. Global guidelines for managing asthma do not recommend the routine use of antimicrobial agents because most episodes of the condition are linked to viral respiratory tract infections (RTI), and bacterial infection appears to have an insignificant impact. However, antibiotics are recommended when there is a high-grade fever, a consolidation on the chest radiograph, and purulent sputum that contains polymorphs rather than eosinophils. Managing acute bronchial asthma with sepsis, specifically the choice of whether or not to initiate antimicrobial treatment, remains difficult since there are currently no practical clinical or radiological markers that allow for a simple distinction between viral and bacterial infections. Researchers found that serum procalcitonin (PCT) values can efficiently and safely minimize antibiotic usage in individuals with severe acute asthma. Again, the clinical manifestations of acute asthma and bacterial RTI are similar, as are frequently used test values, like C-reactive protein (CRP) and white blood cell (WBC) count, making it harder for doctors to differentiate between viral and bacterial infections in asthma patients. The role and scope of each biomarker have not been precisely defined yet, although they have all been established to aid healthcare professionals in their diagnostics and treatment strategies.

Blood Biomarkers of Neonatal Sepsis with Special Emphasis on the Monocyte Distribution Width Value as an Early Sepsis Index

Background and Objectives: Early detection of neonatal sepsis is critical because it is potentially fatal. Therefore, sepsis biomarkers of sufficient sensitivity and specificity are needed. This study aimed to evaluate the utility of peripheral blood parameters as neonatal sepsis biomarkers and the diagnostic performance of the monocyte distribution width (MDW) in sepsis in a neonatal intensive care unit. Materials and Methods: A cross-sectional study was conducted from September 2019 to August 2020 at the King Saud University Medical City in Riyadh, Saudi Arabia. Samples were collected and organised as follows: 77 study cases were subdivided into two subgroups (other health complication (49) and sepsis (28)), and there were 70 controls. The causative microorganisms of neonatal sepsis were isolated. Peripheral blood samples were collected from each neonate in an ethylenediaminetetraacetic acid tube for a complete blood count and a leukocyte differential count. Moreover, the receiver operating characteristic (ROC) curve analysis was used to measure the diagnostic performance of the MDW. Results: The haematological parameters and neonatal sepsis cases had a considerable correlation. The MDW was the most significant haematological parameter. The ROC analysis of the MDW demonstrated that the area under the curve was 0.89 (95% confidence interval: 0.867 to 0.998) with a sensitivity of 89.3%, a specificity of 88.2%, and a negative predictive value of 97.2% at the cut-off point of 23. Conclusions: The use of haematological parameters is feasible and can be performed rapidly. Neonatal sepsis showed a strong correlation with leukopenia, anaemia, thrombocytopenia, and an elevated MDW value. Moreover, the ROC curve analysis confirmed the high diagnostic ability of the MDW in neonatal sepsis prediction.

Basal procalcitonin, C-reactive protein, interleukin-6, and presepsin for prediction of mortality in critically ill septic patients: a systematic review and meta-analysis

BACKGROUND

Numerous biomarkers have been proposed for diagnosis, therapeutic, and prognosis in sepsis. Previous evaluations of the value of biomarkers for predicting mortality due to this life-threatening condition fail to address the complexity of this condition and the risk of bias associated with prognostic studies. We evaluate the predictive performance of four of these biomarkers in the prognosis of mortality through a methodologically sound evaluation.

METHODS

We conducted a systematic review a systematic review and meta-analysis to determine, in critically ill adults with sepsis, whether procalcitonin (PCT), C-reactive protein (CRP), interleukin-6 (IL-6), and presepsin (sCD14) are independent prognostic factors for mortality. We searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials up to March 2023. Only Phase-2 confirmatory prognostic factor studies among critically ill septic adults were included. Random effects meta-analyses pooled the prognostic association estimates.

RESULTS

We included 60 studies (15,681 patients) with 99 biomarker assessments. Quality of the statistical analysis and reporting domains using the QUIPS tool showed high risk of bias in > 60% assessments. The biomarker measurement as a continuous variable in models adjusted by key covariates (age and severity score) for predicting mortality at 28-30 days showed a null or near to null association for basal PCT (pooled OR = 0.99, 95% CI = 0.99-1.003), CRP (OR = 1.01, 95% CI = 0.87 to 1.17), and IL-6 (OR = 1.02, 95% CI = 1.01-1.03) and sCD14 (pooled HR = 1.003, 95% CI = 1.000 to 1.006). Additional meta-analyses accounting for other prognostic covariates had similarly null findings.

CONCLUSION

Baseline, isolated measurement of PCT, CRP, IL-6, and sCD14 has not been shown to help predict mortality in critically ill patients with sepsis. The role of these biomarkers should be evaluated in new studies where the patient selection would be standardized and the measurement of biomarker results.

TRIAL REGISTRATION

PROSPERO (CRD42019128790).

Prognostic implication of downregulated exosomal miRNAs in patients with sepsis: a cross-sectional study with bioinformatics analysis

BACKGROUND

Despite the understanding of sepsis-induced extracellular vesicles (EVs), such as exosomes, and their role in intercellular communication during sepsis, little is known about EV contents such as microRNA (miRNA), which modulate important cellular processes contributing to sepsis in body fluids. This study aimed to analyze the differential expression of exosomal miRNAs in plasma samples collected from sepsis patients and healthy controls, and to identify potential miRNA regulatory pathways contributing to sepsis pathogenesis.

METHODS

Quantitative real-time PCR-based microarrays were used to profile plasma exosomal miRNA expression levels in 135 patients with sepsis and 11 healthy controls from an ongoing prospective registry of critically ill adult patients admitted to the intensive care unit. The identified exosomal miRNAs were tested in an external validation cohort (35 sepsis patients and 10 healthy controls). And then, functional enrichment analyses of gene ontology, KEGG pathway analysis, and protein-protein interaction network and cluster analyses were performed based on the potential target genes of the grouped miRNAs. Finally, to evaluate the performance of the identified exosomal miRNAs in predicting in-hospital and 90-day mortalities of sepsis patients, receiver operating characteristic curve (ROC) and Kaplan-Meier analyses were performed.

RESULTS

Compared with healthy controls, plasma exosomes from sepsis patients showed significant changes in 25 miRNAs; eight miRNAs were upregulated and 17 downregulated. Additionally, the levels of hsa-let-7f-5p, miR-331-3p miR-301a-3p, and miR-335-5p were significantly lower in sepsis patients than in healthy controls (p < 0.0001). These four miRNAs were confirmed in an external validation cohort. In addition, the most common pathway for these four miRNAs were PI3K-Akt and mitogen-activated protein kinase (MAPK) signaling pathways based on the KEGG analysis. The area under the ROC of hsa-let-7f-5p, miR-331-3p, miR-301a-3p, and miR-335-5p level for in-hospital mortality was 0.913, 0.931, 0.929, and 0.957, respectively (p < 0.001), as confirmed in an external validation cohort. Also, the Kaplan-Meier analysis showed a significant difference in 90-day mortality between sepsis patients with high and low miR-335-5p, miR-301a-3p, hsa-let-7f-5p, and miR-331-3p levels (p < 0.001, log-rank test).

CONCLUSION

Among the differentially-expressed miRNAs detected in microarrays, the top four downregulated exosomal miRNAs (hsa-let-7f-5p, miR-331-3p miR-301a-3p, and miR-335-5p) were identified as independent prognostic factors for in-hospital and 90-day mortalities among sepsis patients. Bioinformatics analysis demonstrated that these four microRNAs might provide a significant contribution to sepsis pathogenesis through PI3K-Akt and MAPK signaling pathway.

Comparison of monocyte distribution width and Procalcitonin as diagnostic markers for sepsis: Meta-analysis of diagnostic test accuracy studies

AIM

We aimed to perform a meta-analysis to find out whether PCT and MDW could be used as accurate diagnostic markers for sepsis.

METHODS

We searched PUBMED, WOS, and SCOPUS databases. Inclusion criteria were any observational or clinical trials that compared monocyte Distribution Width [MDW] with Procalcitonin [PCT] as diagnostic markers in a patient with sepsis. Case reports, editorials, conference abstracts, and animal studies were excluded. RevMan software [5.4] was used to perform the meta-analysis.

RESULTS

After the complete screening, 5 observational studies were included in the meta-analysis. The total number of patients included in the meta-analysis in the sepsis group is 565 and 781 in the control group. The pooled analysis between the sepsis group and controls showed a statistically significant association between sepsis and increased levels of MDW and PCT [MD = 3.94, 95% CI = 2.53 to 5.36, p-value < 0.00001] and [MD = 9.29, 95% CI = 0.67 to 17.91, p-value = 0.03] respectively. Moreover, the subgroup analysis showed that the p-value of MDW levels [< 0.00001] is more significant than the p-value of PCT levels = 0.03, the p-value between the two subgroups [< 0.00001]. Additionally, the overall ROC Area for MDW [0.790] > the overall ROC Area for PCT [0.760].

CONCLUSION

Our study revealed a statistically significant association between sepsis and increased MDW and PCT levels compared with controls and the overall ROC Area for MDW is higher than the overall ROC Area for PCT, indicating that the diagnostic accuracy of MDW is higher than PCT.MDW can be used as a diagnostic marker for sepsis patients in the emergency department. More multicenter studies are needed to support our findings.

Early sclerostin assessment in frail elderly patients with sepsis: insights on short- and long-term mortality prediction

Unmet needs challenge clinical management of sepsis especially concerning patient profiling, enhancing recovery, and long-term sequelae. Here, we preliminarily focused on sclerostin (SOST) as a candidate biomarker to encompass such a broad range of clinical needs related to sepsis. Seventy-three septic patients were enrolled at internal medicine wards between January 2017 and December 2019 in this pilot study. Clinical examination and blood sample analyses were collected at enrollment and after 7 and 14 days. SOST levels were assessed on serum by ELISA. Thirty-day mortality was set as primary outcome. In-hospital and long-term mortality (2.5 years of median follow-up) were assessed as secondary outcomes. Patients were frail, elderly, and heterogeneous in terms of comorbidity burden. SOST levels were associated with age, cardiovascular comorbidities, and time to early death (30 days). When regression models were built, SOST displayed a high predictive value toward 30-day mortality (OR 13.459 with 95% CI 1.226-148.017) with ever better performance than validated scoring scales for critical ill patients. Such a predictive value of SOST was further confirmed for in-hospital (HR 10.089 with 95% CI 1.375-74.013) and long-term mortality (HR 5.061 with 95% CI 1.379-18.570). SOST levels generally decreased over 7 to 14 days after enrollment (p for trend < 0.001). The degree of this variation further predicted long-term mortality (HR for Δ SOST T0-day 14: 1.006 with 95% CI 1.001-1.011). Our results suggest a role for SOST in both short- and long-time prediction of worse outcome in septic elderly admitted to internal medicine wards.

Screening of renal clear cell carcinoma prognostic marker genes based on TCGA and GTEx chip data and construction of transcription factor-related regulatory networks

This study aimed to identify prognostic marker genes for renal clear cell carcinoma (RCCC) and construct a regulatory network of transcription factors and prognostic marker genes. Three hundred eighty-six genes were significantly differentially expressed in RCCC, with functional enrichment analysis suggesting a relationship between these genes and kidney function and development. Cox and Lasso regression analyses revealed 10 prognostic marker genes (RNASET2, MSC, DPEP1, FGF1, ATP1A1, CLDN10, PLG, SLC44A1, PCSK1N, and LGI4) that accurately predicted RCCC patient prognosis. Upstream transcription factors of these genes were also identified, and in vitro experiments suggested that ATP1A1 may play a key role in RCCC patient prognosis. The findings of this study provide important insights into the molecular mechanisms of RCCC and may have implications for personalized treatment strategies.

Numerical investigation of the dynamics of a rigid spherical particle in a vortical cross-slot flow at moderate inertia

The study of flow and particle dynamics in microfluidic cross-slot channels is of high relevance for lab-on-a-chip applications. In this work, we investigate the dynamics of a rigid spherical particle in a cross-slot junction for a channel height-to-width ratio of 0.6 and at a Reynolds number of 120 for which a steady vortex exists in the junction area. Using an in-house immersed-boundary-lattice-Boltzmann code, we analyse the effect of the entry position of the particle in the junction and the particle size on the dynamics and trajectory shape of the particle. We find that the dynamics of the particle depend strongly on its lateral entry position in the junction and weakly on its vertical entry position; particles that enter close to the centre show trajectory oscillations. Larger particles have longer residence times in the junction and tend to oscillate less due to their confinement. Our work contributes to the understanding of particle dynamics in intersecting flows and enables the design of optimised geometries for cytometry and particle manipulation.

From Infection to Death: An Overview of the Pathogenesis of Visceral Leishmaniasis

Kala-azar, also known as visceral leishmaniasis (VL), is a disease caused by Leishmania infantum and L. donovani. Patients experience symptoms such as fever, weight loss, paleness, and enlarged liver and spleen. The disease also affects immunosuppressed individuals and has an overall mortality rate of up to 10%. This overview explores the literature on the pathogenesis of preclinical and clinical stages, including studies in vitro and in animal models, as well as complications and death. Asymptomatic infection can result in long-lasting immunity. VL develops in a minority of infected individuals when parasites overcome host defenses and multiply in tissues such as the spleen, liver, and bone marrow. Hepatosplenomegaly occurs due to hyperplasia, resulting from parasite proliferation. A systemic inflammation mediated by cytokines develops, triggering acute phase reactants from the liver. These cytokines can reach the brain, causing fever, cachexia and vomiting. Similar to sepsis, disseminated intravascular coagulation (DIC) occurs due to tissue factor overexpression. Anemia, hypergammaglobulinemia, and edema result from the acute phase response. A regulatory response and lymphocyte depletion increase the risk of bacterial superinfections, which, combined with DIC, are thought to cause death. Our understanding of VL's pathogenesis is limited, and further research is needed to elucidate the preclinical events and clinical manifestations in humans.

[Research advances of sepsis biomarkers]

Sepsis is a life-threatening condition for patients. Biomarkers can be used for the diagnosis, treatment, and prognostic assessment of sepsis. In recent years, new biomarkers for sepsis have been discovered, and more than 250 biomarkers have been identified so far. The complexity of the sepsis process and the increased sensitivity of various detection techniques will lead to the emergence of new biomarkers. However, there is still a lack of specific diagnostic biomarkers and effective therapeutic approaches for sepsis in clinical practice. Therefore, the search for reliable biomarkers and the evaluation of the role of biomarkers in sepsis will undoubtedly aid in clinical decision-making. This article reviews the advances on research of sepsis biomarkers in order to improve understanding of current biomarkers of sepsis, and provide reference for the application of biomarkers in clinical diagnosis, treatment, and prognosis of sepsis.

Lipopolysaccharide-induced sepsis impairs M2R-GIRK signaling in the mouse sinoatrial node

Sepsis has emerged as a global health burden associated with multiple organ dysfunction and 20% mortality rate in patients. Numerous clinical studies over the past two decades have correlated the disease severity and mortality in septic patients with impaired heart rate variability (HRV), as a consequence of impaired chronotropic response of sinoatrial node (SAN) pacemaker activity to vagal/parasympathetic stimulation. However, the molecular mechanism(s) downstream to parasympathetic inputs have not been investigated yet in sepsis, particularly in the SAN. Based on electrocardiography, fluorescence Ca2+ imaging, electrophysiology, and protein assays from organ to subcellular level, we report that impaired muscarinic receptor subtype 2-G protein-activated inwardly-rectifying potassium channel (M2R-GIRK) signaling in a lipopolysaccharide-induced proxy septic mouse model plays a critical role in SAN pacemaking and HRV. The parasympathetic responses to a muscarinic agonist, namely IKACh activation in SAN cells, reduction in Ca2+ mobilization of SAN tissues, lowering of heart rate and increase in HRV, were profoundly attenuated upon lipopolysaccharide-induced sepsis. These functional alterations manifested as a direct consequence of reduced expression of key ion-channel components (GIRK1, GIRK4, and M2R) in the mouse SAN tissues and cells, which was further evident in the human right atrial appendages of septic patients and likely not mediated by the common proinflammatory cytokines elevated in sepsis.

Development and validation of a nomogram for predicting sepsis in patients with pyogenic liver abscess

Pyogenic liver abscess (PLA) is a severe condition that significantly increases the risk of sepsis. However, there is a notable dearth of research regarding the prediction of sepsis in PLA patients. The objective of this study was to develop and validate a prognostic nomogram for predicting sepsis in PLA patients. A total of 206 PLA patients were enrolled in our study, out of which 60 individuals (29.1%) met the Sepsis-3 criteria. Independent risk factors for sepsis were identified through univariate and multivariate logistic regression analyses. Subsequently, a nomogram was developed based on age, positive blood culture, procalcitonin, alanine aminotransferase, blood urea nitrogen, and D-dimer. The nomogram demonstrated excellent calibration and discrimination, as evidenced by the area under the receiver operating characteristic curve (AUC) values of 0.946 (95% confidence interval [CI], 0.912-0.979) and 0.980 (95%CI 0.951-1.000) in the derivation and validation cohorts, respectively. Furthermore, decision-curve analysis confirmed the clinical utility of the nomogram. This study provides valuable insights for the prevention of sepsis in PLA patients and underscores the potential application of the prognostic nomogram in clinical practice.

An appraisal of studies using mouse models to assist the biomarker discovery for sepsis prognosis

Introduction

Clinicians need reliable outcome predictors to improve the prognosis of septic patients. Mouse models are widely used in sepsis research. We aimed to review how mouse models were used to search for novel prognostic biomarkers of sepsis in order to optimize their use for future biomarker discovery.

Methods

We searched PubMed from 2012 to July 2022 using "((sepsis) AND (mice)) AND ((prognosis) OR (prognostic biomarker))".

Results

A total of 412 publications were retrieved. We selected those studies in which mouse sepsis was used to demonstrate prognostic potential of biomarker candidates and/or assist the subsequent evaluation in human sepsis for further appraisal. The most frequent models were lipopolysaccharide (LPS) injection and caecal ligation and puncture (CLP) using young male mice. Discovery technologies applied on mice include setting survival and nonsurvivable groups, detecting changes of biomarker levels and measuring physiological parameters during sepsis. None of the biomarkers achieved sufficient clinical performance for clinical use.

Conclusions

The number of studies and strategies using mouse models to discover prognostic biomarkers of sepsis are limited. Current mouse models need to be further optimized to better conform to human sepsis. Current biomarker platforms do not achieve predictive performance for clinical use.

One biomarker does not fit all: tailoring anti-infective therapy through utilization of procalcitonin and other specific biomarkers

INTRODUCTION

Considering the ongoing increase in antibiotic resistance, the importance of judicious use of antibiotics through reduction of exposure is crucial. Adding procalcitonin (PCT) and other biomarkers to pathogen-specific tests may help to further improve antibiotic therapy algorithms and advance antibiotic stewardship programs to achieve these goals.

AREAS COVERED

In recent years, several trials have investigated the inclusion of biomarkers such as PCT into clinical decision-making algorithms. For adult patients, findings demonstrated improvements in the individualization of antibiotic treatment, particularly for patients with respiratory tract infections and sepsis. While most trials were performed in hospitals with central laboratories, point-of-care testing might further advance the field by providing a cost-effective and rapid diagnostic tool in upcoming years. Furthermore, novel biomarkers including CD-64, presepsin, Pancreatic stone and sTREM-1, have all shown promising results for increased accuracy of sepsis diagnosis. Availability of these markers however is currently still limited and there is insufficient evidence for their routine use in clinical care.

EXPERT OPINION

In addition to new host-response markers, combining such biomarkers with pathogen-directed diagnostics present a promising strategy to increase algorithm accuracy in differentiating between bacterial and viral infections. Recent advances in microbiologic testing using PCR or nucleic amplification tests may further improve the diagnostic yield and promote more targeted pathogen-specific antibiotic therapy.

Differentiating infection, colonisation, and sterile inflammation in critical illness: the emerging role of host-response profiling

Infection results when a pathogen produces host tissue damage and elicits an immune response. Critically ill patients experience immune activation secondary to both sterile and infectious insults, with overlapping clinical phenotypes and underlying immunological mechanisms. Patients also undergo a shift in microbiota with the emergence of pathogen-dominant microbiomes. Whilst the combination of inflammation and microbial shift has long challenged intensivists in the identification of true infection, the advent of highly sensitive molecular diagnostics has further confounded the diagnostic dilemma as the number of microbial detections increases. Given the key role of the host immune response in the development and definition of infection, profiling the host response offers the potential to help unravel the conundrum of distinguishing colonisation and sterile inflammation from true infection. This narrative review provides an overview of current approaches to distinguishing colonisation from infection using routinely available techniques and proposes matrices to support decision-making in this setting. In searching for new tools to better discriminate these states, the review turns to the understanding of the underlying pathobiology of the host response to infection. It then reviews the techniques available to assess this response in a clinically applicable context. It will cover techniques including profiling of transcriptome, protein expression, and immune functional assays, detailing the current state of knowledge in diagnostics along with the challenges and opportunities. The ultimate infection diagnostic tool will likely combine an assessment of both host immune response and sensitive pathogen detection to improve patient management and facilitate antimicrobial stewardship.

Procalcitonin as a biomarker to guide treatments for patients with lower respiratory tract infections

INTRODUCTION

Lower respiratory tract infections are amongst the main causes for hospital/intensive care unit admissions and antimicrobial prescriptions. In order to reduce antimicrobial pressure, antibiotic administration could be optimized through procalcitonin-based algorithms.

AREAS COVERED

In this review, we discuss the performances of procalcitonin for the diagnosis and the management of community-acquired and ventilator-associated pneumonia. We provide up-to-date evidence and deliver clear messages regarding the purpose of procalcitonin to reduce unnecessary antimicrobial exposure.

EXPERT OPINION

Antimicrobial pressure and resulting antimicrobial resistances are a major public health issue as well as a daily struggle in the management of patients with severe infectious diseases, especially in intensive care units where antibiotic exposure is high. Procalcitonin-guided antibiotic administration has proven its efficacy in reducing unnecessary antibiotic use in lower respiratory tract infections without excess in mortality, hospital length of stay or disease relapse. Procalcitonin-guided algorithms should be implemented in wards taking care of patients with severe infections. However, procalcitonin performances are different regarding the setting of the infection (community versus hospital-acquired infections) the antibiotic management (start or termination of antibiotic) as well as patient's condition (immunosuppressed or in shock) and we encourage the physicians to be aware of these limitations.

Plasma Chemerin Is Induced in Critically Ill Patients with Gram-Positive Infections

Chemerin is a chemoattractant protein abundantly expressed in hepatocytes. Chemerin exerts pro- and anti-inflammatory effects and acts as a pro-resolving protein. Chemerin levels are low in patients with liver cirrhosis and are increased in sepsis. The aim of this study was to identify associations between plasma chemerin levels and underlying diseases as well as causes of severe illness. The cohort included 32 patients with liver cirrhosis who had low systemic chemerin, and who were not considered for further evaluation. Plasma chemerin levels were similar between the 27 patients with systemic inflammatory response syndrome (SIRS), the 34 patients with sepsis and the 63 patients with septic shock. Chemerin in plasma correlated with C-reactive protein and leukocyte count but not with procalcitonin, a clinical marker of bacterial infection. Plasma chemerin did not differ among patients with and without ventilation and patients with and without dialysis. Vasopressor therapy was not associated with altered plasma chemerin levels. Infection with severe acute respiratory syndrome coronavirus 2 had no effect on plasma chemerin levels. Baseline levels of plasma chemerin could not discriminate between survivors and non-survivors. Notably, Gram-positive infection was associated with higher chemerin levels. In summary, the current study suggests that plasma chemerin might serve as an early biomarker for the diagnosis of Gram-positive infections in patients with sepsis.

Identification and validation of a novel mitochondrion-related gene signature for diagnosis and immune infiltration in sepsis

Background

Owing to the complex pathophysiological features and heterogeneity of sepsis, current diagnostic methods are not sufficiently precise or timely, causing a delay in treatment. It has been suggested that mitochondrial dysfunction plays a critical role in sepsis. However, the role and mechanism of mitochondria-related genes in the diagnostic and immune microenvironment of sepsis have not been sufficiently investigated.

Methods

Mitochondria-related differentially expressed genes (DEGs) were identified between human sepsis and normal samples from GSE65682 dataset. Least absolute shrinkage and selection operator (LASSO) regression and the Support Vector Machine (SVM) analyses were carried out to locate potential diagnostic biomarkers. Gene ontology and gene set enrichment analyses were conducted to identify the key signaling pathways associated with these biomarker genes. Furthermore, correlation of these genes with the proportion of infiltrating immune cells was estimated using CIBERSORT. The expression and diagnostic value of the diagnostic genes were evaluated using GSE9960 and GSE134347 datasets and septic patients. Furthermore, we established an in vitro sepsis model using lipopolysaccharide (1 µg/mL)-stimulated CP-M191 cells. Mitochondrial morphology and function were evaluated in PBMCs from septic patients and CP-M191 cells, respectively.

Results

In this study, 647 mitochondrion-related DEGs were obtained. Machine learning confirmed six critical mitochondrion-related DEGs, including PID1, CS, CYP1B1, FLVCR1, IFIT2, and MAPK14. We then developed a diagnostic model using the six genes, and receiver operating characteristic (ROC) curves indicated that the novel diagnostic model based on the above six critical genes screened sepsis samples from normal samples with area under the curve (AUC) = 1.000, which was further demonstrated in the GSE9960 and GSE134347 datasets and our cohort. Importantly, we also found that the expression of these genes was associated with different kinds of immune cells. In addition, mitochondrial dysfunction was mainly manifested by the promotion of mitochondrial fragmentation (p<0.05), impaired mitochondrial respiration (p<0.05), decreased mitochondrial membrane potential (p<0.05), and increased reactive oxygen species (ROS) generation (p<0.05) in human sepsis and LPS-simulated in vitro sepsis models.

Conclusion

We constructed a novel diagnostic model containing six MRGs, which has the potential to be an innovative tool for the early diagnosis of sepsis.

Six potential biomarkers in septic shock: a deep bioinformatics and prospective observational study

Background

Septic shock occurs when sepsis is related to severe hypotension and leads to a remarkable high number of deaths. The early diagnosis of septic shock is essential to reduce mortality. High-quality biomarkers can be objectively measured and evaluated as indicators to accurately predict disease diagnosis. However, single-gene prediction efficiency is inadequate; therefore, we identified a risk-score model based on gene signature to elevate predictive efficiency.

Methods

The gene expression profiles of GSE33118 and GSE26440 were downloaded from the Gene Expression Omnibus (GEO) database. These two datasets were merged, and the differentially expressed genes (DEGs) were identified using the limma package in R software. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichments of DEGs were performed. Subsequently, Lasso regression and Boruta feature selection algorithm were combined to identify the hub genes of septic shock. GSE9692 was then subjected to weighted gene co-expression network analysis (WGCNA) to identify the septic shock-related gene modules. Subsequently, the genes within such modules that matched with septic shock-related DEGs were identified as the hub genes of septic shock. To further understand the function and signaling pathways of hub genes, we performed gene set variation analysis (GSVA) and then used the CIBERSORT tool to analyze the immune cell infiltration pattern of diseases. The diagnostic value of hub genes in septic shock was determined using receiver operating characteristic (ROC) analysis and verified using quantitative PCR (qPCR) and Western blotting in our hospital patients with septic shock.

Results

A total of 975 DEGs in the GSE33118 and GSE26440 databases were obtained, of which 30 DEGs were remarkably upregulated. With the use of Lasso regression and Boruta feature selection algorithm, six hub genes (CD177, CLEC5A, CYSTM1, MCEMP1, MMP8, and RGL4) with expression differences in septic shock were screened as potential diagnostic markers for septic shock among the significant DEGs and were further validated in the GSE9692 dataset. WGCNA was used to identify the co-expression modules and module-trait correlation. Enrichment analysis showed significant enrichment in the reactive oxygen species pathway, hypoxia, phosphatidylinositol 3-kinases (PI3K)/Protein Kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling, nuclear factor-κβ/tumor necrosis factor alpha (NF-κβ/TNF-α), and interleukin-6 (IL-6)/Janus Kinase (JAK)/Signal Transducers and Activators of Transcription 3 (STAT3) signaling pathways. The receiver operating characteristic curve (ROC) of these signature genes was 0.938, 0.914, 0.939, 0.956, 0.932, and 0.914, respectively. In the immune cell infiltration analysis, the infiltration of M0 macrophages, activated mast cells, neutrophils, CD8 T cells, and naive B cells was more significant in the septic shock group. In addition, higher expression levels of CD177, CLEC5A, CYSTM1, MCEMP1, MMP8, and RGL4 messenger RNA (mRNA) were observed in peripheral blood mononuclear cells (PBMCs) isolated from septic shock patients than from healthy donors. Higher expression levels of CD177 and MMP8 proteins were also observed in the PBMCs isolated from septic shock patients than from control participants.

Conclusions

CD177, CLEC5A, CYSTM1, MCEMP1, MMP8, and RGL4 were identified as hub genes, which were of considerable value in the early diagnosis of septic shock patients. These preliminary findings are of great significance for studying immune cell infiltration in the pathogenesis of septic shock, which should be further validated in clinical studies and basic studies.

Advances in Rodent Experimental Models of Sepsis

In the development of therapeutic strategies for human diseases, preclinical experimental models have a key role. However, the preclinical immunomodulatory therapies developed using rodent sepsis were not successful in human clinical trials. Sepsis is characterized by a dysregulated inflammation and redox imbalance triggered by infection. Human sepsis is simulated in experimental models using methods that trigger inflammation or infection in the host animals, most often mice or rats. It remains unknown whether the characteristics of the host species, the methods used to induce sepsis, or the molecular processes focused upon need to be revisited in the development of treatment methods that will succeed in human clinical trials. Our goal in this review is to provide a survey of existing experimental models of sepsis, including the use of humanized mice and dirty mice, and to show how these models reflect the clinical course of sepsis. We will discuss the strengths and limitations of these models and present recent advances in this subject area. We maintain that rodent models continue to have an irreplaceable role in studies toward discovering treatment methods for human sepsis.

Validation of circulating histone detection by mass spectrometry for early diagnosis, prognosis, and management of critically ill septic patients

BACKGROUND

As leading contributors to worldwide morbidity and mortality, sepsis and septic shock are considered a major global health concern. Proactive biomarker identification in patients with sepsis suspicion at any time remains a daunting challenge for hospitals. Despite great progress in the understanding of clinical and molecular aspects of sepsis, its definition, diagnosis, and treatment remain challenging, highlighting a need for new biomarkers with potential to improve critically ill patient management. In this study we validate a quantitative mass spectrometry method to measure circulating histone levels in plasma samples for the diagnosis and prognosis of sepsis and septic shock patients.

METHODS

We used the mass spectrometry technique of multiple reaction monitoring to quantify circulating histones H2B and H3 in plasma from a monocenter cohort of critically ill patients admitted to an Intensive Care Unit (ICU) and evaluated its performance for the diagnosis and prognosis of sepsis and septic shock (SS).

RESULTS

Our results highlight the potential of our test for early diagnosis of sepsis and SS. H2B levels above 121.40 ng/mL (IQR 446.70) were indicative of SS. The value of blood circulating histones to identify a subset of SS patients in a more severe stage with associated organ failure was also tested, revealing circulating levels of histones H2B above 435.61 ng/ml (IQR 2407.10) and H3 above 300.61 ng/ml (IQR 912.77) in septic shock patients with organ failure requiring invasive organ support therapies. Importantly, we found levels of H2B and H3 above 400.44 ng/mL (IQR 1335.54) and 258.25 (IQR 470.44), respectively in those patients who debut with disseminated intravascular coagulation (DIC). Finally, a receiver operating characteristic curve (ROC curve) demonstrated the prognostic value of circulating histone H3 to predict fatal outcomes and found for histone H3 an area under the curve (AUC) of 0.720 (CI 0.546-0.895) p < 0.016 on a positive test cut-off point at 486.84 ng/mL, showing a sensitivity of 66.7% and specificity of 73.9%.

CONCLUSIONS

Circulating histones analyzed by MS can be used to diagnose SS and identify patients at high risk of suffering DIC and fatal outcome.

Evaluation of electronic measurement of capillary refill for Sepsis screening at ED triage

OBJECTIVE

To evaluate the association between capillary refill time (CRT) measured by a medical device and sepsis among patients presenting to the Emergency Department (ED).

METHODS

This prospective observational study enrolled adult and pediatric patients during ED triage when sepsis was considered a potential diagnosis by the triage nurse. Patients were enrolled at an academic medical center between December 2020 and June 2022. CRT was measured by a research assistant using an investigational medical device. The outcomes included sepsis and septic shock defined using sep-3 criteria, septic shock defined as IV antibiotics and a vasopressor requirement, ICU admission, and hospital mortality. Other measures included patient demographics and vital signs at ED triage. We evaluated univariate associations between CRT and sepsis outcomes.

RESULTS

We enrolled 563 patients in the study, 48 met Sep-3 criteria, 5 met Sep-3 shock criteria, and 11 met prior septic shock criteria (IV antibiotics and vasopressors to maintain mean arterial pressure of 65). Sixteen patients were admitted to the ICU. The mean age was 49.1 years, and 51% of the cohort was female. The device measured CRT was significantly associated with the diagnosis of sepsis by sep-3 criteria (OR 1.23, 95% CI 1.06-1-43), septic shock by sep-3 criteria (OR 1.57, 95% CI 1.02-2.40), and septic shock defined as receipt of IV antibiotics and a vasopressor requirement (OR 1.37, 95% CI 1.03-1.82). Patients with CRT >3.5 s measured by the DCR device had an odds ratio of 4.67 (95%CI 1.31-16.1) of septic shock (prior definition), and an odds ratio of 3.97 (95% CI 1.99-7.92) of ICU admission, supporting the potential for the 3.5-s cutoff of the DCR measurement.

CONCLUSIONS

CRT measured by a medical device at ED triage was associated with the diagnosis of sepsis. Objective CRT measurement using a medical device may be a relatively simple way to improve sepsis diagnosis during ED triage.

Presepsin: gelsolin ratio, as a promising marker of sepsis-related organ dysfunction: a prospective observational study

Introduction

We aimed to facilitate the diagnosis and prognosis of sepsis-related organ dysfunction through analyzing presepsin (PSEP) and gelsolin (GSN) levels along with a novel marker, the presepsin:gelsolin (PSEP:GSN) ratio.

Methods

Blood samples were collected from septic patients at the intensive care unit (ICU) at three time points (T1-3): T1: within 12 h after admission; T2: second day morning; T3: third day morning. Sampling points for non-septic ICU patients were T1 and T3. PSEP was measured by a chemiluminescence-based POCT method while GSN was determined by an automated immune turbidimetric assay. Data were compared with routine lab and clinical parameters. Patients were categorized by the Sepsis-3 definitions. PSEP:GSN ratio was evaluated in major sepsis-related organ dysfunctions including hemodynamic instability, respiratory insufficiency and acute kidney injury (AKI).

Results

In our single center prospective observational study, 126 patients were enrolled (23 control, 38 non-septic and 65 septic patients). In contrast to controls, significantly elevated (p < 0.001) admission PSEP:GSN ratios were found in non-septic and septic patients. Regarding 10-day mortality prediction, PSEP:GSN ratios were lower (p < 0.05) in survivors than in non-survivors during follow-up, while the prognostic performance of PSEP:GSN ratio was similar to widely used clinical scores (APACHE II, SAPS II, SOFA). PSEP:GSN ratios were also higher (p < 0.001) in patients with sepsis-related AKI than septic non-AKI patients during follow-up, especially in sepsis-related AKI patients needing renal replacement therapy. Furthermore, increasing PSEP:GSN ratios were in good agreement (p < 0.001) with the dosage and the duration of vasopressor requirement in septic patients. Moreover, PSEP:GSN ratios were markedly greater (p < 0.001) in patients with septic shock than in septic patients without shock. Compared to septic patients requiring oxygen supplementation, substantially elevated (p < 0.001) PSEP:GSN ratios were observed in septic patients with demand for mechanical ventilation, while higher PSEP:GSN ratios (p < 0.001) were also associated with extended periods of mechanical ventilation requirement in septic patients.

Conclusion

PSEP:GSN ratio could be a useful complementary marker besides the routinely used SOFA score regarding the diagnosis and short term mortality prediction of sepsis. Furthermore, the significant increase of this biomarker may also indicate the need for prolonged vasopressor or mechanical ventilation requirement of septic patients. PSEP:GSN ratio could yield valuable information regarding the extent of inflammation and the simultaneous depletion of the patient's scavenger capacity during sepsis.

Clinical trail registration

NIH U.S. National Library of Medicine, ClinicalTrails.gov. Trial identifier: NCT05060679, (https://clinicaltrials.gov/ct2/show/NCT05060679) 23.03.2022, Retrospectively registered.

[Individualized treatment in anesthesiology and intensive care medicine]

BACKGROUND

Individualized medicine uses data on biological characteristics of individual patients in order to tailor treatment planning to their unique constitution. With respect to the practice of anesthesiology and intensive care medicine, it bears the potential to systematize the often complex medical care of critically ill patients and to improve outcomes.

OBJECTIVE

The aim of this narrative review is to provide an overview of the possible applications of the principles of individualized medicine in anesthesiology and intensive care medicine.

MATERIAL AND METHODS

Based on a search in MEDLINE, CENTRAL and Google Scholar, the results of previous studies and systematic reviews are narratively synthesized and the implications for the scientific and clinical practice are presented.

RESULTS AND DISCUSSION

There are possibilities for individualization and an increase in precision of patient care in most if not all problems in anesthesiology and symptoms in intensive medical care. Even now, all practicing physicians can initiate measures to individualize treatment at different timepoints throughout the course of treatment. Individualized medicine can supplement and be integrated into protocols. Plans for future applications of individualized medicine interventions should consider the feasibility in a real-world setting. Clinical studies should contain process evaluations in order to create ideal preconditions for a successful implementation. Quality management, audits and feedback should become a standard procedure to ensure sustainability. In the long run, individualization of care, especially in the critically ill, should be enshrined in guidelines and become an integral part of clinical practice.

[Relevant biomarkers in infectiology]

A biomarker in infectiology should ideally be able to identify infectious agents, monitor clinical response and determine the duration of treatment. This article answers the question to what extent C-reactive protein and procalcitonin meet these requirements and reports on the search for further biomarkers - e.g. with the help of "omics"-based technologies and the integration of artificial intelligence.

Target product profiles for diagnosis of sepsis: Proposing a new approach for diagnostic innovation

Background & objectives

Sepsis, including neonatal sepsis, remains a prevalent cause of morbidity and mortality in low- and middle-income countries such as India, representing 85 per cent of all sepsis-related deaths globally. Early diagnosis and timely initiation of treatment is challenging due to non-specific clinical manifestations and non-availability of rapid diagnostic tests. There is an urgent need for affordable diagnostics with fast turnaround time catering to the needs of end-users. Target product profiles (TPPs) have been found instrumental in developing 'fit-for-use' diagnostics, thus reducing the time taken to facilitate development and improving diagnosis. Hitherto, no such guidance or criteria has been defined for rapid diagnostics for sepsis/neonatal sepsis. We propose an innovative approach for developing the diagnostics for sepsis screening and diagnosis which can be utilized by diagnostic developers in the country.

Methods

Thr@ee-round Delphi method, including two online surveys and one virtual consultation, was adopted to define criteria for minimum and optimum attributes of TPPs and build consensus on characteristics. Expert panel (n=23) included infectious disease physicians, public health specialists, clinical microbiologists, virologists, researchers/scientists and technology experts/innovators.

Results

We present a three-component product profile for sepsis diagnosis, (i) screening with high sensitivity, (ii) detection of aetiological agent, and (iii) profiling of antimicrobial susceptibility/resistance, in adults and neonates with an option of testing different considerations. An agreement of >75 per cent was achieved for all TPP characteristics by Delphi. These TPPs are tailored to the Indian healthcare settings and can also be extrapolated to other resource-constraint and high-disease burden settings.

Interpretation & conclusions

Diagnostics developed using these TPPs will facilitate utilization of invested resources leading to development of the products that have potential to ease the economic burden on patient and save lives.

Shengjiang San alleviated sepsis-induced lung injury through its bidirectional regulatory effect

BACKGROUND

Sepsis is a life-threatening organ dysfunction caused by dysregulated host responses to infection, for which effective therapeutic strategies are still absent. Shengjiang San (SJS), a well-known Traditional Chinese Medicine formula, has been widely used clinically. However, its role in sepsis-induced lung injury remains unclear.

METHODS

To explore its specific mechanism, we firstly established a sepsis animal model using cecal ligation and puncture (CLP) and treated MH-S cells with LPS plus ATP. Then, UPLC/Q-TOF-MS/MS was utilized to identify its active ingredients. Network pharmacology analysis was performed to uncover the potential mechanism. HE staining and biochemical analysis were conducted to validate its therapeutic effect. ELISA was applied to detect the release of pro-inflammatory and anti-inflammatory cytokines. Western blot was utilized to detect the protein levels of GSDMD, NLRP3, P65, ASC and caspase-1.

RESULTS

SJS could dramatically increase the survival rate of sepsis. In addition, it is able to inhibit the pro-inflammatory cytokines release at day 1 post CLP while promote their production at day 7, indicating SJS could attenuate uncontrolled inflammatory response in the early stage and improve immunosuppression in the late phase. Network pharmacology analysis showed that pyroptosis is the crucial action SJS exerted in the protection of sepsis-induced lung injury. Western blot data implicated SJS could attenuate pyroptosis in early sepsis while enhance in the late phase.

CONCLUSIONS

SJS acted to alleviate sepsis-induced lung injury through its bidirectional regulatory effect.

Treatment Advances in Sepsis and Septic Shock: Modulating Pro- and Anti-Inflammatory Mechanisms

Sepsis is currently defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection, and it affects over 25 million people every year. Even more severe, septic shock is a subset of sepsis defined by persistent hypotension, and hospital mortality rates are higher than 40%. Although early sepsis mortality has greatly improved in the past few years, sepsis patients who survive the hyperinflammation and subsequent organ damage often die from long-term complications, such as secondary infection, and despite decades of clinical trials targeting this stage of the disease, currently, no sepsis-specific therapies exist. As new pathophysiological mechanisms have been uncovered, immunostimulatory therapy has emerged as a promising path forward. Highly investigated treatment strategies include cytokines and growth factors, immune checkpoint inhibitors, and even cellular therapies. There is much to be learned from related illnesses, and immunotherapy trials in oncology, as well as the recent COVID-19 pandemic, have greatly informed sepsis research. Although the journey ahead is a long one, the stratification of patients according to their immune status and the employment of combination therapies represent a hopeful way forward.