The Global Epidemiology of Sepsis. Does It Matter That We Know So Little?

Defining sepsis in small animals

OBJECTIVE

To discuss the definitions of sepsis in human and veterinary medicine.

DESIGN

International, multicenter position statement on the need for consensus definitions of sepsis in veterinary medicine.

SETTING

Veterinary private practice and university teaching hospitals.

ANIMALS

Dogs and cats.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Sepsis is a life-threatening condition associated with the body's response to an infection. In human medicine, sepsis has been defined by consensus on 3 occasions, most recently in 2016. In veterinary medicine, there is little uniformity in how sepsis is defined and no consensus on how to identify it clinically. Most publications rely on modified criteria derived from the 1991 and 2001 human consensus definitions. There is a divergence between the human and veterinary descriptions of sepsis and no consensus on how to diagnose the syndrome. This impedes research, hampers the translation of pathophysiology insights to the clinic, and limits our abilities to optimize patient care. It may be time to formally define sepsis in veterinary medicine to help the field move forward. In this narrative review, we present a synopsis of prior attempts to define sepsis in human and veterinary medicine, discuss developments in our understanding, and highlight some criticisms and shortcomings of existing schemes.

CONCLUSIONS

This review is intended to serve as the foundation of current efforts to establish a consensus definition for sepsis in small animals and ultimately generate evidence-based criteria for its recognition in veterinary clinical practice.

Chicoric acid ameliorates sepsis-induced cardiomyopathy via regulating macrophage metabolism reprogramming

BACKGROUND

Sepsis-related cardiac dysfunction is believed to be a primary cause of high morbidity and mortality. Metabolic reprogramming is closely linked to NLRP3 inflammasome activation and dysregulated glycolysis in activated macrophages, leading to inflammatory responses in septic cardiomyopathy. Succinate dehydrogenase (SDH) and succinate play critical roles in the progression of metabolic reprogramming in macrophages. Inhibition of SDH may be postulated as an effective strategy to attenuate macrophage activation and sepsis-induced cardiac injury.

PURPOSE

This investigation was designed to examine the role of potential compounds that target SDH in septic cardiomyopathy and the underlying mechanisms involved.

METHODS/RESULTS

From a small molecule pool containing about 179 phenolic compounds, we found that chicoric acid (CA) had the strongest ability to inhibit SDH activity in macrophages. Lipopolysaccharide (LPS) exposure stimulated SDH activity, succinate accumulation and superoxide anion production, promoted mitochondrial dysfunction, and induced the expression of hypoxia-inducible factor-1α (HIF-1α) in macrophages, while CA ameliorated these changes. CA pretreatment reduced glycolysis by elevating the NAD+/NADH ratio in activated macrophages. In addition, CA promoted the dissociation of K(lysine) acetyltransferase 2A (KAT2A) from α-tubulin, and thus reducing α-tubulin acetylation, a critical event in the assembly and activation of NLRP3 inflammasome. Overexpression of KAT2A neutralized the effects of CA, indicating that CA inactivated NLRP3 inflammasome in a specific manner that depended on KAT2A inhibition. Importantly, CA protected the heart against endotoxin insult and improved sepsis-induced cardiac mitochondrial structure and function disruption. Collectively, CA downregulated HIF-1α expression via SDH inactivation and glycolysis downregulation in macrophages, leading to NLRP3 inflammasome inactivation and the improvement of sepsis-induced myocardial injury.

CONCLUSION

These results highlight the therapeutic role of CA in the resolution of sepsis-induced cardiac inflammation.

Sepsis-associated acute kidney injury in the intensive care unit: incidence, patient characteristics, timing, trajectory, treatment, and associated outcomes. A multicenter, observational study

PURPOSE

The Acute Disease Quality Initiative (ADQI) Workgroup recently released a consensus definition of sepsis-associated acute kidney injury (SA-AKI), combining Sepsis-3 and Kidney Disease Improving Global Outcomes (KDIGO) AKI criteria. This study aims to describe the epidemiology of SA-AKI.

METHODS

This is a retrospective cohort study carried out in 12 intensive care units (ICUs) from 2015 to 2021. We studied the incidence, patient characteristics, timing, trajectory, treatment, and associated outcomes of SA-AKI based on the ADQI definition.

RESULTS

Out of 84,528 admissions, 13,451 met the SA-AKI criteria with its incidence peaking at 18% in 2021. SA-AKI patients were typically admitted from home via the emergency department (ED) with a median time to SA-AKI diagnosis of 1 day (interquartile range (IQR) 1-1) from ICU admission. At diagnosis, most SA-AKI patients (54%) had a stage 1 AKI, mostly due to the low urinary output (UO) criterion only (65%). Compared to diagnosis by creatinine alone, or by both UO and creatinine criteria, patients diagnosed by UO alone had lower renal replacement therapy (RRT) requirements (2.8% vs 18% vs 50%; p < 0.001), which was consistent across all stages of AKI. SA-AKI hospital mortality was 18% and SA-AKI was independently associated with increased mortality. In SA-AKI, diagnosis by low UO only, compared to creatinine alone or to both UO and creatinine criteria, carried an odds ratio of 0.34 (95% confidence interval (CI) 0.32-0.36) for mortality.

CONCLUSION

SA-AKI occurs in 1 in 6 ICU patients, is diagnosed on day 1 and carries significant morbidity and mortality risk with patients mostly admitted from home via the ED. However, most SA-AKI is stage 1 and mostly due to low UO, which carries much lower risk than diagnosis by other criteria.

Anti-inflammatory and anti-biotic drug metronidazole loaded ZIF-90 nanoparticles as a pH responsive drug delivery system for improved pediatric sepsis management

Sepsis is a life-threatening disease caused by the dis-functioning of the immune response to pathogenic infections. Despite, the discovery of modern therapeutics and treatments of sepsis are lacking due to the resistance of pathogens. Metronidazole is an antibiotic commonly used to treat bacterial infections, but usage is limited and challenging by a short half-life period. In this research work, fabricate a pH-responsive drug delivery system for controlled release of metronidazole targeted molecules. We exemplified that, the encapsulation of hydrophilic metronidazole drug within a hydrophobic ZIF-90 framework can be enhanced the pH-responsive drug release under acidic conditions. The ZIF-90 frameworks only decompose in under acidic solutions, they are highly stable in physiological conditions. The pH-responsive protonation mechanism of ZIF-90 frameworks promotes the quick release of metronidazole within cells. The antimicrobial proficiency of zinc and metronidazole will expose a synergistic effect in ROS-mediated bacterial inhibition and auto-immunity boosting of normal cells. In vitro, antibacterial activity results revealed that the MI@ZIF-90 nano drug delivery system effectively eradicated human infectious pathogens at the lowest concentrations. In anti-fungal activity, studies show excellent growth inhibition against human pathogenic fungi Aspergillus fumigatus and Candida albicans. Finally, the PBMC cytocompatibility study concludes, that the fabricated MI@ZIF-90 drug delivery system is non-toxic to biomedical applications. The overall research findings highlight the design of a smart drug delivery system for sepsis treatment. In future it will be an efficient, low-cost, and biocompatible pharmaceutics for pediatric sepsis management processes.

The Therapeutic Effect of an Anti-TNF-α/HSA/IL-6R Triple-Specific Fusion Protein Under Experimental Septic Conditions

Sepsis caused by a dysregulated host response to infection is a life-threatening disease that can lead to organ dysfunction. Due to its unclear and complex mechanism, effective medicine for the treatment of sepsis is urgently required. The extensive release of cytokines and other mediators like TNF-α and interleukin-6 (IL-6) play critical roles in the development of sepsis. The present study aims to evaluate the potential protective effects of an anti-TNF-α/HSA/IL-6R triple-specific fusion protein (TAL-6) under septic experimental conditions. The anti-TNF-α/HSA/IL-6R triple-specific fusion protein (TAL-6), which links three published single domain antibodies, was designed and constructed in our lab. High purity fusion proteins were obtained with high binding affinity for TNF-α (94.75 pM), human serum albumin (1.83 nM) and IL-6R (2.29 nM). TAL-6 protected mouse fibroblast fibrosarcoma cells (L929) from apoptosis induced by TNF-α, establishing that the expressed fusion proteins can selectively interact with TNF-α in vitro. In vivo, the survival rate of cecal ligation and puncture (CLP) was notably increased in the group with TAL-6 treatment and significantly higher compared with the single-targeted IL-6R and TNF-α fusion protein at the same dose. After treatment with TAL-6, the serum levels of TNF-α, IL-1β, and IL-6 were significantly decreased, and sepsis-induced pathological injuries in the kidney were remarkably attenuated. TAL-6 is therefore a potential candidate for the development of new drugs against sepsis in human.

Improving sepsis screening and care in a developing nation health setting: A description of implementation

Evidence on sepsis screening and care in developing nations is insufficient to inform implementation practices in hospital wards. The aim of this multi-method study was to describe and evaluate the implementation of a three-step intervention (sepsis screening, alert activation, care) in five wards in Argentina in 2017. The implementation involved three stages: (1) context assessment, (2) development/participation in implementation strategies, and (3) evaluation of intervention adherence. Results were variable. The context assessment (Stage 1) demonstrated the value of education, proactivity towards care and team structures. Strategies developed (Stage 2) included sepsis screening and response guide, education, team rounding, posters, champions, audit/feedback and knowledge brokering. In Stage 3, staff screened 92% patients (506/547) for sepsis at ≥60% of set times; only 33% (21/64) patients had a sepsis alert activated when needed. A similar proportion of patients who had alerts activated (n = 16, 76%) or not (n = 32, 74%) received at least one element of care. The use of implementation strategies resulted in adherence to some aspects of the intervention. Future research is needed to improve sepsis screening and alert activation and care in this setting.

Association Between Nutritional Risk Screening Score and Prognosis of Patients with Sepsis

Background

Malnutrition is one of the most critical factors affecting patients’ risk of infection and length of stay, and it may affect the prognosis of patients with sepsis. There have been no studies that have applied nutritional risk screening tools to stratify patients with sepsis according to prognosis.

Methods

We retrospectively analyzed the clinical data of 425 adult sepsis inpatients who were grouped based on nutritional risk screening (NRS) score, including a nutrition score, disease severity score, and age score. Prognostic factors were analyzed using univariate and multivariate regression analyses.

Results

Of the enrolled patients, 174 had an NRS score of ≥3; these patients were older and had a longer hospitalization time but lower body mass index (BMI), albumin (ALB) than others. Univariate Cox regression analysis showed that age, ALB, C-reactive protein (CRP), and NRS score were significantly (P<0.05) associated with in-hospital mortality. Multivariate analysis showed that age (hazard ratio [HR]=1.020, 95% confidence interval [CI]: 1.005–1.036; P=0.008) and ALB (HR=0.924, 95% CI: 0.885–0.966; P<0.001) were independent risk factors for sepsis-related mortality. The Kaplan–Meier analysis revealed that the cumulative in-hospital mortality of sepsis patients with an NRS score of ≥3 was significantly higher than that of patients with an NRS score of <3 (P=0.022).

Conclusion

NRS scores can effectively risk stratify sepsis patients. Patients with high NRS scores should be monitored more closely to halt further disease progression.

Sheathless and high-throughput elasto-inertial bacterial sorting for enhancing molecular diagnosis of bloodstream infection

Purification of bacteria from human blood samples is essential for rapid identification of pathogens by molecular methods, enabling faster and more accurate diagnosis of bloodstream infection than conventional gold standard blood culture methods. The inertial microfluidic method has been broadly studied to isolate biological cells of interest in various biomedical applications due to its label-free and high-throughput advantages. However, because of the bacteria's tininess, which ranges from 0.5 μm to 3 μm, they are challenging to be effectively focused and sorted out in existing inertial microfluidic devices that work well with biological cells larger than 10 μm. Efforts have been made to sort bacterial cells by utilizing extremely small channel dimensions or employing a sheath flow, which thus results in limitations on the throughput and ease of operation. To overcome this challenge, we develop a method that integrates a non-Newtonian fluid with a novel channel design to allow bacteria to be successfully sorted from larger blood cells in a channel dimension of 120 μm × 20 μm without the use of sheath flows. The throughput of this device with four parallel channels is above 400 μL per minute. The real-time polymerase chain reaction (qPCR) analysis indicates that our inertial sorting approach has a nearly 3-fold improvement in pathogen recovery compared with the commonly used lysis-centrifugation method at pathogen abundances as low as 102 cfu mL-1. With the rapid and simple purification and enrichment of bacterial pathogens, the present inertial sorting method exhibits an ability to enhance the fast and accurate molecular diagnosis of bloodstream bacterial infection.

A Translational Investigation of IFN-α and STAT1 Signaling in Endothelial Cells during Septic Shock Provides Therapeutic Perspectives

Septic shock and disseminated intravascular coagulation (DIC) are known to be characterized by an endothelial cell dysfunction. The molecular mechanisms underlying this relationship are, however, poorly understood. In this work, we aimed to investigate human circulating IFN-α in patients with septic shock-induced DIC and tested the potential role of endothelial Stat1 (signal transducer and activator of transcription 1) as a therapeutic target in a mouse model of sepsis. For this, circulating type I, type II, and type III IFNs and procoagulant microvesicles were quantified in a prospective cohort of patients with septic shock. Next, we used a septic shock model induced by cecal ligation and puncture in wild-type mice, in Ifnar1 (type I IFN receptor subunit 1)-knockout mice, and in Stat1 conditional knockout mice. In human samples, we observed higher concentrations of circulating IFN-α and IFN-α1 in patients with DIC compared with patients without DIC, whereas concentrations of IFN-β, IFN-γ, IFN-λ1, IFN-λ2, and IFN-λ3 were not different. IFN-α concentration was positively correlated with CD105 microvesicle concentrations, reflecting endothelial injury. In Ifnar1^-/- mice, cecal ligation and puncture did not induce septic shock and was characterized by lesser endothelial cell injury, with lower aortic inflammatory cytokine expression, endothelial inflammatory-related gene expression, and fibrinolysis. In mice in which Stat1 was specifically ablated in endothelial cells, a marked protection against sepsis was also observed, suggesting the relevance of an endothelium-targeted strategy. Our work highlights the key roles of type I IFNs as pathogenic players in septic shock-induced DIC and the potential pertinence of endothelial STAT1 as a therapeutic target.

Transglutaminase 2 as a Marker for Inflammation and Therapeutic Target in Sepsis

Sepsis results in lethal organ malfunction due to dysregulated host response to infection, which is a condition with increasing prevalence worldwide. Transglutaminase 2 (TG2) is a crosslinking enzyme that forms a covalent bond between lysine and glutamine. TG2 plays important roles in diverse cellular processes, including extracellular matrix stabilization, cytoskeletal function, cell motility, adhesion, signal transduction, apoptosis, and cell survival. We have shown that the co-culture of Candida albicans and hepatocytes activates and induces the translocation of TG2 into the nucleus. In addition, the expression and activation of TG2 in liver macrophages was dramatically induced in the lipopolysaccharide-injected and cecal ligation puncture-operated mouse models of sepsis. Based on these findings and recently published research, we have reviewed the current understanding of the relationship between TG2 and sepsis. Following the genetic and pharmacological inhibition of TG2, we also assessed the evidence regarding the use of TG2 as a potential marker and therapeutic target in inflammation and sepsis.

Lipopolysaccharide Administration Alters Extracellular Vesicles in Cell Lines and Mice

Extracellular vesicles (EVs) play a fundamental role in cell and infection biology and have the potential to act as biomarkers for novel diagnostic tools. In this study, we explored the in vitro impact of bacterial lipopolysaccharide administration on cell lines that represents a target for bacterial infection in the host. Administration of lipopolysaccharide at varying concentrations to A549 and BV-2 cell lines caused only modest changes in cell death, but EV numbers were significantly changed. After treatment with the highest concentration of lipopolysaccharide, EVs derived from A549 cells packaged significantly less interleukin-6 and lysosomal-associated membrane protein 1. EVs derived from BV-2 cells packaged significantly less tumor necrosis factor after administration of lipopolysaccharide concentrations of 0.1 µg/mL and 1 µg/mL. We also examined the impact of lipopolysaccharide administration on exosome biogenesis and cargo composition in BALB/c mice. Serum-isolated EVs from lipopolysaccharide-treated mice showed significantly increased lysosomal-associated membrane protein 1 and toll-like receptor 4 levels compared with EVs from control mice. In summary, this study demonstrated that EV numbers and cargo were altered using these in vitro and in vivo models of bacterial infection.

Sepsis and septic shock in France: incidences, outcomes and costs of care

Background

Sepsis is one of the leading causes of death worldwide. The associated incidence, mortality and trends do not differ greatly between documented reports. The purpose of this study was to provide an in-depth description of patients with sepsis and septic shock hospitalized in France from 2010 to 2015 and to explore the temporal trends of their clinical characteristics, costs and outcomes.

Methods

Retrospective cohort study of the French hospital administrative database in which organ failure therapies and severity scores are systematically registered. All patients admitted between 2010 and 2015 for sepsis and septic shock as defined by an ICD-10 code for infection, and for organ failure or the use of organ failure supplementation were included. Incidence, outcomes and trends were analyzed. Subgroup analyses based on several coding strategies and adjusted for severity scores were performed.

Results

A total of 737,147 patients with sepsis and 492,902 patients with septic shock were included. From 2010 to 2015, the incidence of sepsis and septic shock increased, respectively, from 206 to 243 and from 135 to 171 cases per 100,000 population. Case fatality remained at 34% for sepsis, but decreased from 46 to 44% for septic shock.

Median hospital stay costs amounted to €11,400 (IQR: 5036; 24,364) for patients with sepsis and €16,439 (IQR: 7339; 29,360) for patients with septic shock.

After adjustment for case-mix and illness severity, the risk of death was stable for sepsis (0.08% [− 0.04; 0.20] per year), but decreased for sepsis patients admitted to the intensive care unit and for cases of septic shock (− 0.33%[ − 0.40; − 0.27] per year).

Conclusions

Sepsis is common, frequently fatal and expensive to treat. Its incidence has increased. Case fatality has decreased in most severely affected patients, owing partly to general improvements in care.

Toll-like receptors in sepsis-associated cytokine storm and their endogenous negative regulators as future immunomodulatory targets

•

Sepsis infects more than 48.9 million people world-wide, with 19.7 million deaths.

•

Cytokine storm plays a significant role in sepsis, along with severe COVID-19.

•

TLR signaling pathways plays a crucial role in generating the cytokine storm.

•

Endogenous negative regulators of TLR signaling are crucial to regulate cytokine storm.

Cytokine storm generates during various systemic acute infections, including sepsis and current pandemic called COVID-19 (severe) causing devastating inflammatory conditions, which include multi-organ failure or multi-organ dysfunction syndrome (MODS) and death of the patient. Toll-like receptors (TLRs) are one of the major pattern recognition receptors (PRRs) expressed by immune cells as well as non-immune cells, including neurons, which play a crucial role in generating cytokine storm. They recognize microbial-associated molecular patterns (MAMPs, expressed by pathogens) and damage or death-associate molecular patterns (DAMPs; released and/expressed by damaged/killed host cells). Upon recognition of MAMPs and DAMPs, TLRs activate downstream signaling pathways releasing several pro-inflammatory mediators [cytokines, chemokines, interferons, and reactive oxygen and nitrogen species (ROS or RNS)], which cause acute inflammation meant to control the pathogen and repair the damage. Induction of an exaggerated response due to genetic makeup of the host and/or persistence of the pathogen due to its evasion mechanisms may lead to severe systemic inflammatory condition called sepsis in response to the generation of cytokine storm and organ dysfunction. The activation of TLR-induced inflammatory response is hardwired to the induction of several negative feedback mechanisms that come into play to conclude the response and maintain immune homeostasis. This state-of-the-art review describes the importance of TLR signaling in the onset of the sepsis-associated cytokine storm and discusses various host-derived endogenous negative regulators of TLR signaling pathways. The subject is very important as there is a vast array of genes and processes implicated in these negative feedback mechanisms. These molecules and mechanisms can be targeted for developing novel therapeutic drugs for cytokine storm-associated diseases, including sepsis, severe COVID-19, and other inflammatory diseases, where TLR-signaling plays a significant role.

GPR120 Ameliorates Apoptosis and Inhibits the Production of Inflammatory Cytokines in Renal Tubular Epithelial Cells

Acute kidney injury (AKI) is the most common complication of sepsis with a high mortality rate. In this study, we focus on the renal injury caused by the immune response of renal tubular epithelial cells and inflammation-induced renal tubular epithelial cell apoptosis. We studied the role of GRP120 in the inflammation and apoptosis of human renal cell line HK-2 and mouse primary renal tubular epithelial cells. GPR120 agonist GW9508 activated the GPR120 pathway. Inflammatory factors were detected using quantitative real-time PCR and enzyme-linked immunosorbent assay. Cell apoptosis experiments included the annexin V and PI double-staining method combined with flow cytometry, TUNEL method, and Western blot. The level of cytokines including TNF-α, IL-6, IL-1β, and iNOS was significantly decreased (P < 0.05) in HK-2 and TECs after the activation of the GPR120 pathway. Besides, the cell apoptosis of both cells increased. Overexpressed GPR120 and shGPR120 were established. Treatment with lipopolysaccharide (LPS) increased the level of cytokines including TNF-α, IL-6, IL-1β, and iNOS in HK-2 cell and TECs. Compared with control-LPS and negative control (NC)-LPS, the overexpression of GPR120 and shGPR120 could decrease and increase the level of secreted cytokines significantly (P < 0.05), respectively, after LPS-induced apoptosis. After H₂O₂- and LPS-induced apoptosis, respectively, compared with the control and NC groups, overexpressed GPR120 and shGPR120 could reduce and increase the expression of caspase-3, respectively. GPR120 could suppress the cellular immune response and apoptosis in renal tubular epithelial cells, thereby possibly protecting the kidney and relieving sepsis-induced AKI.

Cephalosporin Resistance in Escherichia coli Isolated from Children with Septicemia in Mainland China from 2007 to 2017: A Systematic Review and Meta-Analysis

Background: Septicemia in children in mainland China has recently become a public health concern. Methods: A meta-analysis was performed on studies investigating the prevalence of cephalosporin-resistant Escherichia coli isolated from children with septicemia in mainland China from 2007 to 2017 following a search of relevant databases. Results: A total of 43 articles reporting 11 cephalosporins were included in the review. The results of the meta-analysis revealed that for the first-generation cephalosporins, the pooled summarized prevalence of resistance to cefazolin was 74.96% (95% confidence interval [CI]: 64.79-83.91) and cephalothin resistance was 62.28% (95% CI: 36.45-100). Regarding the second-generation cephalosporins, cefoxitin-resistant E. coli comprised 23.85% (95% CI: 10.60-40.40) and cefuroxime resistance was 60.32% (95% CI: 51.25-68.73). For the third-generation cephalosporins, the pooled summarized prevalence of resistance was 51.34% for cefotaxime (95% CI: 40.08-62.54), 40.43% for ceftazidime (95% CI: 31.07-50.15), 45.51% for cefoperazone (95% CI: 20.41-70.61), 12.10% for cefoperazone/sulbactam (95% CI: 6.55-18.76), 62.99% for ceftriaxone (95% CI: 55.00-70.98), and 0% for cefotetan. Among the fourth-generation cephalosporins, resistance to cefepime was 34.08% (95% CI: 25.91-43.31). Conclusions: Most third-generation cephalosporins (e.g., cefotaxime and ceftriaxone) retained high resistance rates throughout the 11-year study period without significant changes. The new fourth-generation cephalosporin, cefepime, is rapidly gaining resistance. Interestingly, ceftazidime, cefepime, and cefoperazone/sulbactam showed a recent decreasing trend of drug resistance. These situations may present a risk for treating children with septicemia and should be closely monitored and treated.

Immunomodulatory and Therapeutic Effects of Mesenchymal Stem Cells on Organ Dysfunction in Sepsis

ABSTRACT

Sepsis is a life-threatening disorder that is caused by a dysregulated inflammatory response during an infection. The disease mostly affects pregnant women, newborns, and patients in intensive care units. Sepsis treatment is a significant part of a country's health budgets. Delay in the therapy causes irreversible failure of various organs due to the lack of blood supply and reduction of oxygen in the tissues and eventually increased mortality. The involvement of four or five organs by sepsis has been attributed to an increased risk of death to over 90%. Although antibiotics are at the first line of sepsis treatment, they do not possess enough potency to control the disease and prevent subsequent organ failure. The immunomodulatory, anti-inflammatory, anti-apoptotic, and anti-microbial properties of mesenchymal stem cells (MSCs) have been reported in various studies. Therefore, the application of MSCs has been considered a potentially promising therapeutic strategy. In preclinical studies, the administration of MSCs has been associated with reduced bacterial load and decreased levels of pro-inflammatory factors as well as the improved function of the different vital organs, including heart, kidney, liver, and lungs. The current study provides a brief review of sepsis and its pathophysiology, and then highlights recent findings in the therapeutic effects of MSCs and MSC-derived secretome in improving sepsis-induced organ dysfunction. Besides, eligible sepsis candidates for MSC-therapy and the latest clinical findings in these areas have been reviewed.

Predictive Accuracy of the Quick Sepsis-related Organ Failure Assessment Score in Brazil. A Prospective Multicenter Study

Rationale: Although proposed as a clinical prompt to sepsis based on predictive validity for mortality, the Quick Sepsis-related Organ Failure Assessment (qSOFA) score is often used as a screening tool, which requires high sensitivity.

Objectives: To assess the predictive accuracy of qSOFA for mortality in Brazil, focusing on sensitivity.

Methods: We prospectively collected data from two cohorts of emergency department and ward patients. Cohort 1 included patients with suspected infection but without organ dysfunction or sepsis (22 hospitals: 3 public and 19 private). Cohort 2 included patients with sepsis (54 hospitals: 24 public and 28 private). The primary outcome was in-hospital mortality. The predictive accuracy of qSOFA was examined considering only the worst values before the suspicion of infection or sepsis.

Measurements and Main Results: Cohort 1 contained 5,460 patients (mortality rate, 14.0%; 95% confidence interval [CI], 13.1–15.0), among whom 78.3% had a qSOFA score less than or equal to 1 (mortality rate, 8.3%; 95% CI, 7.5–9.1). The sensitivity of a qSOFA score greater than or equal to 2 for predicting mortality was 53.9% and the 95% CI was 50.3 to 57.5. The sensitivity was higher for a qSOFA greater than or equal to 1 (84.9%; 95% CI, 82.1–87.3), a qSOFA score greater than or equal to 1 or lactate greater than 2 mmol/L (91.3%; 95% CI, 89.0–93.2), and systemic inflammatory response syndrome plus organ dysfunction (68.7%; 95% CI, 65.2–71.9). Cohort 2 contained 4,711 patients, among whom 62.3% had a qSOFA score less than or equal to 1 (mortality rate, 17.3%; 95% CI, 15.9–18.7), whereas in public hospitals the mortality rate was 39.3% (95% CI, 35.5–43.3).

Conclusions: A qSOFA score greater than or equal to 2 has low sensitivity for predicting death in patients with suspected infection in a developing country. Using a qSOFA score greater than or equal to 2 as a screening tool for sepsis may miss patients who ultimately die. Using a qSOFA score greater than or equal to 1 or adding lactate to a qSOFA score greater than or equal to 1 may improve sensitivity.

Clinical trial registered with www.clinicaltrials.gov (NCT03158493).

Circulating Histones Are Major Mediators of Multiple Organ Dysfunction Syndrome in Acute Critical Illnesses

OBJECTIVES

Multiple organ dysfunction syndrome is characterized by simultaneous multiple organ failure, which is the leading cause of death in acute critically ill patients. However, what mediates multiple organ dysfunction syndrome is not fully understood. The discovery of toxic effects by extracellular histones on different individual organs strongly suggests their involvement in multiple organ dysfunction syndrome. In this study, we investigate whether circulating histones are major mediators of multiple organ dysfunction syndrome in acute critical illnesses.

DESIGN

Combination of retrospective clinical studies and animal models with intervention.

SETTING

ICU in a tertiary hospital and research laboratories.

PATIENTS

Four hundred and twenty ICU patients, including sepsis (140), severe trauma (63), severe pancreatitis (89), and other admission diagnoses (128).

LABORATORY INVESTIGATION

Cells from major organs are treated with calf thymus histones or histone-containing sera. Animal models for sepsis, trauma, and acute pancreatitis are treated with antihistone reagents.

INTERVENTION

Antihistone reagents in in vitro, ex vivo, and animal models.

MEASUREMENT AND MAIN RESULTS

Retrospective analysis of a prospectively recruited ICU cohort demonstrated a strong correlation between circulating histones and organ injury markers and Sequential Organ Failure Assessment scores. Ex vivo experiments showed that patient sera containing high histone levels were toxic to cultured cells from different origins, suggesting their universal toxicity to multiple organs. Animal models of sepsis, trauma, and pancreatitis further demonstrated a temporal correlation between histone levels and disease severity and multiple organ injury. Importantly, antihistone reagents, that is, antihistone single-chain variable fragment and nonanticoagulant heparin, could dramatically reduce multiple organ injury, particularly of the heart and lungs, and improve survival in mouse models.

CONCLUSIONS

High levels of circulating histones are major mediators of multiple organ dysfunction syndrome. Our results indicate that monitoring upon ICU admission could inform on disease severity and developing antihistone therapy holds great potential of reducing multiple organ dysfunction syndrome and improving survival of critically ill patients.

Socio-demographic characteristics associated with hospitalization for sepsis among adults in Canada: a Census-linked cohort study

PURPOSE

Sepsis is a considerable health system burden. Population-based epidemiological surveillance of sepsis is limited to basic data available in administrative databases. We sought to determine if routinely collected Census data, linked to hospitalization data, can provide a broad socio-demographic profile of patients admitted to Canadian hospitals with sepsis.

METHODS

Linking the 2006 long-form Canadian Census (most recent available for linkage) to the Discharge Abstract Data from 2006/2007 to 2008/2009, we created a population-based cohort of approximately 3,433,900 Canadians. Patients admitted to hospital with sepsis were identified using the Canadian Institute for Health Information administrative data definition. Age-standardized hospital admission rates for sepsis were calculated. Multivariable modelling was used to examine the relationship between Census characteristics and hospitalization with sepsis.

RESULTS

Of those individuals successfully linked to the 2006 long-form Canadian Census, 10,400 patients of 18 yr and older were admitted to hospital with sepsis between the fiscal years 2006/2007 and 2008/2009. These individuals represented a weighted count of approximately 49,000 Canadians from all provinces and territories, excluding Quebec. The age-standardized rate of sepsis hospitalization was 96 cases/100,000 population. Of these, 37/100,000 cases were classified as severe sepsis. The association of Census characteristics with sepsis hospitalization varied with age. In all age-specific models, male sex, never being married, visible minority status, having functional limitations, and not being in the labour force were associated with an increased odds of hospital admission.

CONCLUSIONS

Census data identified broad socio-demographic risk factors for admission to hospital with sepsis. Consideration should be given to incorporating Census data linked to administrative hospital data in population-based epidemiologic surveillance.

Dynamic changes in human HLA-DRA gene expression and Th cell subsets in sepsis: Indications of immunosuppression and associated outcomes

BACKGROUND

Sepsis is a life-threatening disease that is an immune disorder response that causes multiple organ dysfunction. In this study, we investigated the dynamic changes in mRNA expression of HLA-DRA gene and the specific transcription factor of helper T cell subsets to explore long-term immunophenotyping and its relationship with prognosis.

METHODS

Seventy-eight sepsis patients and twelve healthy controls were recruited in this study. Blood samples were collected at eight-time points during their septic course and were assayed for the gene expression of HLA-DRA and T helper cell subset-specific transcription factors (T-bet: Th1, GATA3: Th2, Foxp3: Treg, RORC: Th17).

RESULTS

The levels of HLA-DRA in survivors gradually increased but were maintained at lower levels in non-survivors. The specific transcription factor of Th1 and Th2 cells, T-bet and GATA-3 were significantly lower in sepsis patients than in normal controls, and the non-survivors showed significantly lower levels than the survivors (P < .05). RORC and FOXP3, the specific transcription factor of Treg and Th17 were significantly higher in survivors than in non-survivors and normal controls (P < .05). T-bet and GATA-3 had a linear correlation with HLA-DRA expression (P < .01).

CONCLUSIONS

The dynamic changes in HLA-DRA expression in peripheral blood could accurately reflect the immune status of sepsis patients, and the reduction in HLA-DRA may be an important reason for abnormal T cell differentiation. The sustained low levels of the Th cell subsets (Th1 and Th2) suggest the suppression of adaptive immunity, and this persistent immunosuppression may be the leading cause of death in septic patients.

Are Corticosteroids Beneficial for Sepsis and Septic Shock? Based on Pooling Analysis of 16 Studies

Background: A host of systematic reviews and meta-analyses were carried out to estimate the role of corticosteroids in sepsis and septic shock. Discordant opinions were investigated to determine whether patients who experienced sepsis and septic shock could benefit from corticosteroids treatment. Our purpose is to perform a systematic review of overlapping meta-analyses, to explore the role of corticosteroids in the treatment of sepsis and septic shock.

Method: Ovid MEDLINE, EMBase, Cochrane Database of Systematic Reviews, and LILACS were searched for eligible studies. Two authors individually extracted the relevant data and evaluated the quality of the meta-analysis using A MeaSurement Tool to Assess systematic Reviews 2 (AMSTAR 2) and ROBIS. The Jadad decision algorithm was implemented to identify the meta-analyses that offered the optimal level of evidence.

Result: Sixteen meta-analyses met the eligibility criteria. None of the studies that reported mortality illustrated a significant improvement on mortality (14-day and 90-day), but a 28-day mortality on a long course of a low dose corticosteroids was described. Only four studies stated that a long course of low-dose corticosteroids had advantageous effect on 28-day mortality. A meta-analysis by Fang et al. was regarded as the highest level of evidence in the Jadad decision algorithm among the meta-analyses that were investigated in this systematic review.

Conclusion: The 28-day mortality was reduced, as well as the mortality in the ICU and hospital and the length of stay in the ICU, using a long course of low-dose corticosteroids. This was demonstrated by a meta-analysis of the current optimal available evidence. Additionally, significant improvements on the adverse events of hyperglycemia and hypernatraemia have been made.

P2X4 receptors, immunity, and sepsis

Sepsis is life-threatening systemic organ dysfunction caused by a deregulated host response to an infectious insult. Currently, the treatment of sepsis is limited to the use of antibiotics, fluids, and cardiovascular/respiratory support. Despite these interventions, septic mortality remains high, with reduced life quality in survivors. For this reason, the identification of novel drug targets is a pressing task of modern pharmacology. According to a recent research, it appears that P2 purinergic receptors, which can regulate the host's response to infections, have been identified as potential targets for the treatment of sepsis. Among P2 receptors, the P2X₄ receptor has recently captured the attention of the research community owing to its role in protecting against infections, inflammation, and organ injury. The present review provides an outline of the role played by P2X₄ receptors in the modulation of the host's response to sepsis and the promise that targeting this receptor holds in the treatment of sepsis.

Antimicrobial agent prescription: a prospective cohort study in patients with sepsis and septic shock

OBJECTIVE

To assess the true association between appropriate prescription of antibiotics and prognosis in patients with sepsis, a key issue in health care and quality improvement strategies.

METHODS

Prospective cohort study in three university hospitals to determine whether the empirical prescription of antibiotics was adequate or inadequate, and to compare hospital death rates and length of stay according to different classifications of antibiotics prescription. Logistic regression models for risk estimation were fitted.

RESULTS

A total of 705 patients with severe sepsis were included. No differences were found in positive-culture patients (n = 545) regarding the risk of death with insufficient spectrum antibiotics, compared to patients who received adequate spectrum antibiotics (OR = 0.90; 95% CI = 0.55-1.48). Delay in initiating antibiotics was not associated with the risk of death in patients with adequate spectrum of antibiotics, either with positive (OR = 1.04; 95% CI = 0.99-1.08) or negative cultures (OR = 0.98; 95% CI = 0.92-1.04). There were no differences in the length of hospital stay, according to the antibiotic prescription (median 11 days, IQR = 7-18 days for the whole cohort).

CONCLUSIONS

No associations were found between inadequate antibiotic prescription or delay to initiate therapy and mortality or length of stay.

Sepsis in Intensive Care Unit Patients: Worldwide Data From the Intensive Care over Nations Audit

Background

There is a need to better define the epidemiology of sepsis in intensive care units (ICUs) around the globe.

Methods

The Intensive Care over Nations (ICON) audit prospectively collected data on all adult (>16 years) patients admitted to the ICU between May 8 and May 18, 2012, except those admitted for less than 24 hours for routine postoperative surveillance. Data were collected daily for a maximum of 28 days in the ICU, and patients were followed up for outcome data until death, hospital discharge, or for 60 days. Participation was entirely voluntary.

Results

The audit included 10069 patients from Europe (54.1%), Asia (19.2%), America (17.1%), and other continents (9.6%). Sepsis, defined as infection with associated organ failure, was identified during the ICU stay in 2973 (29.5%) patients, including in 1808 (18.0%) already at ICU admission. Occurrence rates of sepsis varied from 13.6% to 39.3% in the different regions. Overall ICU and hospital mortality rates were 25.8% and 35.3%, respectively, in patients with sepsis, but it varied from 11.9% and 19.3% (Oceania) to 39.5% and 47.2% (Africa), respectively. After adjustment for possible confounders in a multilevel analysis, independent risk factors for in-hospital death included older age, higher simplified acute physiology II score, comorbid cancer, chronic heart failure (New York Heart Association Classification III/IV), cirrhosis, use of mechanical ventilation or renal replacement therapy, and infection with Acinetobacter spp.

Conclusions

Sepsis remains a major health problem in ICU patients worldwide and is associated with high mortality rates. However, there is wide variability in the sepsis rate and outcomes in ICU patients around the globe.

Sepsis-related mortality in China: a descriptive analysis

PURPOSE

A population-level description and analysis of sepsis-related mortality in China is key to the planning and assessment of interventional strategies.

METHODS

Retrospective analysis of multiple cause of death (MCOD) recorded in the population-based national mortality surveillance system (NMSS) of China. All sepsis-related deaths occurring in 605 disease surveillance points (DSPs) covering 323.8 million population across China were included in our study. Age-standardized mortality and national estimate of sepsis-related deaths were estimated using the census population in 2010 and 2015, respectively.

RESULTS

In 2015, a total of 1,937,299 deaths occurring in any of the 605 DSPs and standardized sepsis-related mortality rate was 66.7 (95% confidence interval [CI] 66.4-67.0) deaths per 100,000 population. This produced a national estimate of 1,025,997 sepsis-related deaths. Sepsis-related mortality rates exhibited significant geographic variation. In multilevel analysis, male sex (rate ratio [RR] 1.582, 95% CI 1.570-1.595), increasing age (RR 1.914 for 5-year group, 95% CI 1.910-1.917), and presence of comorbidity (RR 2.316, 95% CI 2.298-2.335) were independently associated with increased sepsis-related mortality. Higher disposable income (RR 0.717 for the fourth interquartile range vs. the first interquartile range, 95% CI 0.515-0.978) and mean years of education (RR 0.808 for the fourth interquartile range vs. the first interquartile range, 95% CI 0.684-0.955) were negatively associated with sepsis-related mortality. However, population-based hospital doctors were not significantly associated with sepsis-related mortality.

CONCLUSIONS

The standardized sepsis-related mortality rate in China was high and varied according to socioeconomic indices, even though some uncertainty remained.

T cells and their immunometabolism: A novel way to understanding sepsis immunopathogenesis and future therapeutics

Sepsis has always been considered as a big challenge for pharmaceutical companies in terms of discovering and designing new therapeutics. The pathogenesis of sepsis involves aberrant activation of innate immune cells (i.e. macrophages, neutrophils etc.) at early stages. However, a stage of immunosuppression is also observed during sepsis even in the patients who have recovered from it. This stage of immunosuppression is observed due to the loss of conventional (i.e. CD4⁺, CD8⁺) T cells, Th17 cells and an upregulation of regulatory T cells (Tregs). This process also impacts metabolic processes controlling immune cell metabolism called immunometabolism. The present review is focused on the T cell-mediated immune response, their immunometabolism and targeting T cell immunometabolism during sepsis as future therapeutic approach. The first part of the manuscripts describes an impact of sepsis on conventional T cells, Th17 cells and Tregs along with their impact on sepsis. The subsequent section further describes the immunometabolism of these cells (CD4⁺, CD8⁺, Th17, and Tregs) under normal conditions and during sepsis-induced immunosuppression. The article ends with the therapeutic targeting of T cell immunometabolism (both conventional T cells and Tregs) during sepsis as a future immunomodulatory approach for its management.

Effects of interleukin-6 and IL-6/AMPK signaling pathway on mitochondrial biogenesis and astrocytes viability under experimental septic condition

OBJECTIVE

Interleukin-6 (IL-6) is a neuromodulation factor with extensive and complex biological activities. IL-6 has been reported to activate AMPK, while AMPK regulates mitochondrial biogenesis and autophagy. The aim of this study was to investigate the role of IL-6 in mitochondrial biogenesis using astrocytes under experimental septic condition and examined how IL-6/AMPK signaling pathway affected this process.

METHODS

The primary cultures of cerebral cortical astrocytes were randomly allocated into six groups: control group, LPS+IFN-γ group, IL-6 group (LPS+IFN-γ+IL-6), C group (LPS+IFN-γ+IL-6+Compound C), siRNA group (LPS+IFN-γ+IL-6+IL-6R siRNA) and siRNA+C group (LPS+IFN-γ+IL-6+IL-6R siRNA+ Compound C). All groups were stimulated for 6 h. Cytokines and reactive oxygen species (ROS) analyses, detection of adenosine triphosphate (ATP), mtDNA content and cell viability, evaluation of the mitochondrial ultrastructure and volume density, western blots of proteins associated with mitochondrial biogenesis and phospho-adenosine monophosphate activated protein kinase (p-AMPK) were performed respectively.

RESULTS

Compared with LPS+IFN-γ group, IL-6 group had milder ultrastructural damage of mitochondria, higher mtDNA content and mitochondrial volume density, higher expression of proteins associated with mitochondrial biogenesis (PGC-1α, NRF-1 and TFAM) and p-AMPK, and thus higher cell viability, whereas blocking IL-6/AMPK signaling pathway, the protective effect of IL-6 has been diminished, compared with IL-6 group.

CONCLUSION

IL-6 enhances mitochondrial biogenesis in astrocytes under experimental septic condition through IL-6/AMPK signaling pathway.

CE: Managing Sepsis and Septic Shock: Current Guidelines and Definitions

: Sepsis is a leading cause of critical illness and hospital mortality. Early recognition and intervention are essential for the survival of patients with this syndrome. In 2002, the Society of Critical Care Medicine (SCCM) and the European Society of Intensive Care Medicine (ESICM) launched the Surviving Sepsis Campaign (SSC) to reduce overall patient morbidity and mortality from sepsis and septic shock by driving practice initiatives based on current best evidence. The SSC guidelines have been updated every four years, with the most recent update completed in 2016. The new guidelines have increased the focus on early identification of infection, risks for sepsis and septic shock, rapid antibiotic administration, and aggressive fluid resuscitation to restore tissue perfusion.In 2014, the SCCM and the ESICM convened a task force of specialists to reexamine the definitions of terms used to identify patients along the sepsis continuum. In 2016, this task force published the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). The new definitions and recommendations included tools, based on an updated understanding of the pathobiology of sepsis, that can be used to predict adverse outcomes in patients with infection.This article discusses the new SSC treatment guidelines, changes in the sepsis bundle interventions, and the Sepsis-3 definitions and tools, all of which enable nurses to improve patient outcomes through timely collaborative action.

The prognostic value of serum PCT, hs-CRP, and IL-6 in patients with sepsis

Objective

To evaluate the prognostic value of serum procalcitonin (PCT), high-sensitivity C-reactive protein (hs-CRP), and interleukin-6 (IL-6) in patients with sepsis.

Methods

Sixty-six patients with sepsis were recruited in the 6th affiliated hospital of Wenzhou Medical University from February 2012 to April 2016. According to status of death or survival within 4 weeks, the patients were divided into death group (n=14) and survival group (n=52). The serum PCT concentration on the day of hospitalization was measured by double antibody immunosorbent assay, hs-CRP serum level was measured by immunoturbidimetric assay, and IL-6 serum concentration was tested by enzyme-linked immunosorbent assay (ELISA) of the included 66 patients. Serum PCT, hs-CRP, and IL-6 were compared between the two groups. The prognostic performance of serum PCT, hs-CRP, and IL-6 in patients with sepsis was evaluated through sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve (AUC).

Results

The serum concentrations of PCT, hs-CRP, and IL-6 in the death group were significantly higher than those of the survival group on the day of hospitalization (P<0.05). The sensitivities of serum PCT, hs-CRP, and IL-6 to predict the mortality of septic patients within 4 weeks were 94.64%, 83.93%, and 82.14%, and the specificities were 73.33%, 64.29%, and 71.43%, respectively. The areas under the ROC curves were 0.88, 0.76, and 0.77.

Conclusion

The serum levels of PCT, hs-CRP and IL-6 were significantly elevated in the death group, which could be used as serological markers to predict the risk of death for sepsis patients within 4 weeks.

Sepsis induced by cecal ligation and perforation (CLP) alters nucleotidase activities in platelets of rats

Sepsis is a potentially lethal condition, and it is associated with platelet alterations. The present study sought to investigate the activity of ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase), E-5'-nucleotidase, and ecto-adenosine deaminase (E-ADA) in the platelets of rats that were induced with sepsis. Male Wistar rats were divided into three groups of ten animals each: a negative control group (normal; NC); a group that underwent surgical procedures (sham); and a group that underwent cecal ligation and perforation (CLP). The induction of sepsis was confirmed by bacteremia, and the causative pathogen identified was Escherichia coli. Hematological parameters showed leukocytosis and thrombocytopenia in animals in the septic group. The results also revealed that there were significant (p < 0.05) increases in adenosine triphosphate (ATP) and adenosine monophosphate (AMP) hydrolyses, and in the deamination of adenosine in the CLP group compared to the sham and control groups. Conversely, ADP hydrolysis was significantly decreased (p < 0.05) in the CLP group compared to the sham and control groups. Purine levels were analyzed by high-performance liquid chromatography (HPLC) in serum samples from control, sham, and CLP groups. Increased concentrations of ATP, adenosine, and inosine were found in the CLP group compared to the sham and control groups. Conversely, the concentrations of ADP and AMP in the CPL group were not significantly altered. We suggest that alterations in hematological parameters, nucleotide hydrolysis in platelets, and nucleotide concentrations in serum samples of rats with induced sepsis may be related to thromboembolic events.

Glucose-Insulin-Potassium Alleviates Intestinal Mucosal Barrier Injuries Involving Decreased Expression of Uncoupling Protein 2 and NLR Family-Pyrin Domain-Containing 3 Inflammasome in Polymicrobial Sepsis

Uncoupling protein 2 (UCP2) may be critical for intestinal barrier function which may play a key role in the development of sepsis, and insulin has been reported to have anti-inflammatory effects. Male Sprague-Dawley rats were randomly allocated into five groups: control group, cecal ligation and puncture (CLP) group, sham surgery group, CLP plus glucose-insulin-potassium (GIK) group, and CLP plus glucose and potassium (GK) group. Ileum tissues were collected at 24 h after surgery. Histological and cytokine analyses, intestinal permeability tests, and western blots of intestinal epithelial tight junction component proteins and UCP2 were performed. Compared with CLP group, the CLP + GIK group had milder histological damage, lower levels of cytokines in the serum and ileum tissue samples, and lower UCP2 expression, whereas the CLP + GK group had no such effects. Moreover, the CLP + GIK group exhibited decreased epithelial permeability of the ileum and increased expression of zonula occludens-1, occludin, and claudin-1 in the ileum. The findings demonstrated that the UCP2 and NLR family-pyrin domain-containing 3/caspase 1/interleukin 1β signaling pathway may be involved in intestinal barrier injury and that GIK treatment decreased intestinal barrier permeability. Thus, GIK may be a useful treatment for intestinal barrier injury during sepsis.

Ultra performance liquid chromatography tandem mass spectrometry assay for determination of kukoamine B in human blood and urine

In this paper, we report a sensitive and rapid ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method which is capable of quantifying kukoamine B (KB) levels in human blood and urine. Following solid phase extraction and direct dilution process, the analyte and its internal standard (D5-KB) run on an Acquity UPLC(®) HSS T3 column (2.1×50mm i.d., 1.8μm) by using a gradient elution method (run time was 1.5min). The mass spectrometric analysis was performed by using an API-5500 mass spectrometer coupled with an electro-spray ionization source. The MRM transitions of m/z 531.3(+)→222.1(+) and 536.3(+)→222.1(+) were used to quantify KB and D5-KB respectively. This assay method has been fully validated in terms of selectivity, linearity, lower limit of quantification, precision, accuracy, stability, recovery and matrix effect. The concentration range of this method is 10.0-2000.0ngmL(-1) in blood and 0.5-500.0ngmL(-1) in urine. Linearity (R(2)) of calibration curves were 0.9964±0.0022 and 0.9935±0.0053 for blood and urine, respectively (regression equation: y=ax+b). The precision (RSD%) of quality control samples is less than 10.3% for blood and less than 10.5% for urine. The accuracy (RE%) is within -4.0-11.3% and -11.7-12.5% for blood and urine respectively. KB was stable after 4h in ice-water bath, 1 freeze/thaw cycles and 180days at -80°C for blood samples; and was stable after 3h at room temperature, 3 freeze/thaw cycles and 180days at -80°C for urine samples. Recoveries of KB were 4.7±0.9% in blood and 96.5±1.3% in urine, respectively. Additionally, the applicability of this method has been proved by analyzing clinical samples from pharmacokinetic study of KB in human.

Current epidemiology of sepsis in mainland China

The disease burden of sepsis is a global issue. Most of the large-scale epidemiological investigations on sepsis have been carried out in developed countries. The population of 1.3 billion in mainland China accounts for approximately 1/5^th of the whole world population. Thus, the knowledge of the incidence and mortality of sepsis in mainland China is vital before employing measures for its improvement. However, most of the epidemiological data of sepsis in mainland China was obtained from ICU settings, and thus lacks the population-based incidence and mortality of sepsis. In the present review, we summarized the limited literature encompassing the incidence, mortality, long-term outcome, and pathogens of sepsis in mainland China. Therefore, it might provide some valuable information regarding the sepsis disease burden and current issues in the management of sepsis in mainland China.