Rethinking the concept of sepsis and septic shock

Value of blood perfusion index in guiding fluid resuscitation against septic shock

ObjectiveSeptic shock is a serious medical condition characterized by extreme inflammation and blood vessel permeability. Fluid resuscitation is a crucial treatment for septic shock, but the optimal approach for fluid management remains controversial. In this study, we explored how blood perfusion index (PI) monitoring can help direct fluid resuscitation therapy for septic shock.MethodsBetween January 2019 and December 2021, 50 patients with septic shock were admitted to The Affiliated Hospital of Hangzhou Normal University and randomly assigned to either a control or study group (25 cases each). All patients were given the sepsis treatment bundle recommended by the 2018 guidelines and were subjected to Pulse Indicator Continuous Cardiac Output (PiCCO) -based hemodynamic monitoring. Fluid resuscitation was administered based on specific indicators in the control group. We used PI to direct fluid resuscitation in the research group. Several parameters were assessed, including blood lactate (BLAC), hemoglobin (Hb), stroke volume index (SVI), norepinephrine dosage, extravascular lung water (EVLW), volume of resuscitation fluid and the ICU mortality.ResultsThere were statistically significant reductions in BLAC in the study group compared to the control group 6 h, 24 h, and 48 h after treatment (P < 0.05). In the study group, the SVI was higher 24 and 48 h post-treatment compared to the control group (P < 0.05). Norepinephrine doses were similarly lowered in the study group. In the comparison of extravascular lung water between the two groups, the extravascular lung water in the study group was less than that in the control group 24 h after fluid resuscitation, and the difference was statistically significant. the ICU mortality [44%vs. 56% (X2 = 0.720, P = 0.572)] in the study group were lower than those in the control group, but the difference had no statistical significance.ConclusionsIn patients with septic shock, fluid resuscitation guided by PI monitoring improves BLAC and SVI while decreasing norepinephrine dosage, and avoid the risk of fluid overload due to increased EVLW fluid overload, demonstrating clinical significance and application value.

A comparative study of ceftazidime/avibactam-based and fosfomycin plus meropenem-based regimens for managing infections caused by carbapenem-resistant Klebsiella pneumoniae in critically ill patients

The main aim of this study was to compare and analyze the effectiveness of treatment regimens using ceftazidime/avibactam (CAZ/AVI) versus fosfomycin plus meropenem (FOS/MER) for managing bloodstream infections (BSI) or ventilator-associated pneumonia (VAP) caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) in critically ill patients. Between 4 January 2019, and 16 July 2023, adult patients (≥18 years old) diagnosed with BSI or VAP due to culture confirmed CRKP in ICU of a tertiary care hospital were investigated retrospectively. A total of 71 patients were categorized into two groups: 30 patients in CAZ/AVI-based, and 41 patients in FOS/MER-based group. No substantial disparities were found in the total duration of ICU hospitalization, as well as the 14- and 30-day mortality rates, between patients treated with CAZ/AVI-based and FOS/MER-based therapeutic regimens. We consider that our study provides for the first time a comprehensive understanding of treatment outcomes and associated risk factors among patients with CRKP-related infections.

CD3D and CD247 are the molecular targets of septic shock

Septic shock is a serious systemic disease with circulatory failure and abnormal cell metabolism caused by sepsis. However, the relationship between CD3D and CD247 and septic shock remains unclear. The septic shock datasets GSE33118 and GSE142255 profiles were generated from the gene expression omnibus databases GPl570, GPl17586. Differentially expressed genes (DEGs) were screened and weighted gene co-expression network analysis was performed. The construction and analysis of protein-protein interaction (PPI) network, functional enrichment analysis, gene set enrichment analysis (GSEA) were performed. Gene expression heat map was drawn. Immune infiltration analysis was performed. Comparative toxicogenomics database (CTD) analysis were performed to find the disease most related to the core gene. Targets can was used to screen miRNAs regulating the hub DEGs. 467 DEGs were identified. According to the gene ontology analysis, they were mainly enriched in the regulation of immune response, cell activation, signaling receptor activity, enzyme binding. Kyoto encyclopedia of genes and genomes analysis showed that they were mainly enriched in the TCR signaling pathway, Fc epsilon RI signaling pathway. GSEA showed that the DEGs were mainly enriched in immune response regulation, cell activation, TCR signaling pathway, Fc epsilon RI signaling pathway. Positive regulation of Fc receptor signaling pathway, PID IL12 2 pathway, immune response was observed in go enrichment items in the enrichment items of metascape. PPI networks got 5 core genes. Gene expression heat map showed that 5 core genes (CD247, Lck, cd3e, cd3d, ITK) were lowly expressed in the sepsis shock samples and highly expressed in the normal samples. CTD analysis showed that 5 core genes (CD247, Lck, cd3e, cd3d, ITK) were found to be associated with hemorrhage and necrosis. Low expression of cd3d, CD247 was observed in septic shock, and the lower the level of cd3d, CD247, the worse the prognosis.

Accuracy of SIRS, age-adapted pSOFA, and quick SOFA scoring systems for predicting outcomes in paediatric patients with sepsis: a meta-analysis

BACKGROUND

Sepsis is the leading cause of mortality in children. Several scoring systems are used to predict outcome and mortality for pediatric patients with sepsis, but how they compare to each other in terms of sensitivity and specificity is unclear.

METHODS

The systematic literature review was performed following PRISMA guidelines. Publically accessible search engines and study databases such as PubMed, CENTRAL (Cochrane Central Register of Controlled Trials), and Google Scholar were scanned for articles published from January 1990 to March 2021 using relevant key words. All relevant studies were analyzed separately by two reviewers. A random-effects model was used to calculate the pooled sensitivity and pooled specificity with a 95% confidence interval (CI). Heterogeneity was evaluated using I², which estimates the percentage of variation between study results due to heterogeneity rather than sampling error.

RESULTS

Eleven studies met inclusion criteria and evaluated the SOFA scoring system. The pooled sensitivity, specificity, and SROC for prediction of mortality were 83% (95% CI: 76%-88%), 72% (95% CI: 60%-81%), and 85% (95% CI: 82%-88%), respectively. Six studies examined the SIRS system. Pooled sensitivity, specificity, and SROC were 80% (95% CI: 64%-90%), 36% (95% CI: 23%-51%), and 59% (95% CI: 55%-63%), respectively.

CONCLUSION

This meta-analysis shows that SOFA was superior to SIRS for predicting mortality in PICU patients with sepsis. Additional prospective multi-centric studies are needed to better evaluate and validate this finding.

Prognostic value of diagnostic scales in community-acquired sepsis mortality at an emergency service. Prognosis in community-adquired sepsis

Objectives

To asses the prognostic value of diagnostic scales in mortality of community-adquired sepsis and added value of additional parameters.

Methods

Prospective observational study of patients with community-adquired sepsis in the Emergency Room of University Hospital. The study population were patients presented in the Emergency Room with confirmed infection and practicians sepsis diagnosis. Demographics, triage vital signs, inhaled oxygen fraction, inflammatory markers, biochemistry, all-cause mortality during hospitalization and three months after were recorded. Prognostic value of qSOFA, NEWS, SOFA, SIRS, and amplified scales were calculated by using logistic regression and ROC curves.

Results

201 patients, 54% male, average age 77±11,2 years were included. Sixty-three (31.5%) died during hospitalization and 24 (12%) three months after discharge. At the time of admission vital signs related with in-hospital mortality were Glasgow Coma Scale <13, respiratory rate ≥22 bpm, temperature, oxygen desaturation, high flow oxygen therapy and heart rate. Patients dead in-hospital had lower PaCO2, higher lactate, glucose and creatinine. Greater predictive capacity of the scales, from higher to lower, was: qSOFA, NEWS2, SOFA and SIRS. Amplified scales with lactate >2mg/dl, glucose, blood level >190mg/dl and PaCO2 <35mmHg improved predictive value.

Conclusion

Amplified-qSOFA and amplified-NEWS2 scales at Emergency Department may offer a better prognostic of septic patients mortality.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12873-021-00532-1.

qSOFA score for prediction of sepsis outcome in emergency department

Objective:

The third international consensus definition for sepsis and septic shock (sepsis 3) task force recently introduced qSOFA (quick sequential organ failure assessment) as a score for detection of patients at risk of sepsis outside of intensive care units. We performed this study to evaluate the validity of qSOFA for early detection and risk stratification of septic patients in emergency department.

Methods:

We conducted this study in an emergency department of the largest university affiliated hospital in northwest of Iran from Sept 2015 to Sept 2016. One hundred and forty patients who were SIRS positive with a suspected infection without alternative diagnosis and a microbiological proven infection were enrolled in this study. qSOFA was calculated for each patient and correlated with sepsis grades and mortality.

Results:

From 140 patients 84 (60%) had positive qSOFA score and 56 (40%) patients had negative qSOFA score. Our results showed that near half of patients with positive qSOFA expired during their stay in hospital while this was about 5% for patients with negative qSOFA. ROC curve of study regarding prediction of outcome with qSOFA showed an area under curve of 0.59. (P value: 0.04). Time spent to sepsis detection was 16 minutes shorter with qSOFA score compared to SIRS criteria in this study.

Conclusion:

In patients with suspected sepsis, qSOFA has acceptable value for risk stratification of severity, multi organ failure and mortality. It seems that education of medical staff and frequent screening of patients for warning signs can help to increase the value of qSOFA in prediction of mortality in critically ill septic patients.

Paraoxonase-1 activity evaluation as a diagnostic and prognostic marker in horses and foals

Background

In several species, paraoxonase‐1 (PON‐1) decreases during inflammation, because of the presence of oxidative stress; its measurement recently has been validated in horses, but its role as a clinical biomarker is unknown.

Objectives

To evaluate sensitivity, specificity and likelihood ratio of PON‐1 activity to identify systemic inflammatory response syndrome (SIRS)‐positive horses or horses with a poor prognosis.

Animals

One hundred seventy‐two blood samples from 58 sick horses from 3 different veterinary hospitals.

Methods

In a cross‐sectional study, PON‐1 activity was measured upon admission and at 24‐hour intervals until discharge or death, and results were analyzed based on SIRS status and outcome.

Results

No statistically significant difference was found in median PON‐1 activity between SIRS and non‐SIRS cases or between survivors and non‐survivors except for mares, in which PON‐1 activity was significantly lower in SIRS‐positive horses (P = .05). The sensitivity of PON‐1 activity in identifying horses with SIRS or negative outcome was low (0.0%‐46.2% depending on the examined group) but its specificity was high (87.0%‐100.0%). However, when PON‐1 is low, the likelihood of death is 2.40‐3.89 times higher than the likelihood of survival. Repeated measurement of PON‐1 after treatment does not predict outcome.

Conclusions and Clinical Importance

Evaluation of PON‐1 activity in horses with inflammation might be advisable in the future, but only low activity at admission may be relevant in predicting SIRS or negative outcome.

[Paediatric sequential organ failure assessment (pSOFA) score: A new mortality prediction score in the paediatric intensive care unit]

OBJECTIVES

To assess performance of the age-adapted SOFA score in children admitted into Paediatric Intensive Care Units (PICUs) and whether the SOFA score can compete with the systemic inflammatory response syndrome (SIRS) in diagnosing sepsis, as recommended in the Sepsis-3 consensus definitions.

METHODS

Two-centre prospective observational study in 281 children admitted to the PICU. We calculated the SOFA, Pediatric Risk of Mortality (PRISM), and Pediatric Index of Mortality-2 (PIM2) scores and assessed for the presence of SIRS at admission. The primary outcome was 30-day mortality.

RESULTS

The SOFA score was higher in nonsurvivors (P<.001) and mortality increased progressively across patient subgroups from lower to higher SOFA scores. The receiver operating characteristic (ROC) curve analysis revealed that the area under the curve (AUC) of the SOFA score for predicting 30-day mortality was 0.89, compared to AUCs of 0.84 and 0.79 for the PRISM and PIM2 scores, respectively. The AUC of the SOFA score for predicting a prolonged stay in the PICU was 0.67. The SOFA score was correlated to the PRISM score (r_s=0.59) and the PIM2 score (r_s=0.51). In children with infection, the AUC of the SOFA score for predicting mortality was 0.87 compared to an AUC of 0.60 using SIRS. The diagnosis of sepsis applying a SOFA cutoff of 3 points predicted mortality better than both the SIRS and the SOFA cutoff of 2 points recommended by the Sepsis-3 consensus.

CONCLUSIONS

The SOFA score at admission is useful for predicting outcomes in the general PICU population and is more accurate than SIRS for definition of paediatric sepsis.

Eicosanoids derived from cytochrome P450 pathway of arachidonic acid and inflammatory shock

Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. Septic shock, the most common form of vasodilatory shock, is a subset of sepsis in which circulatory and cellular/metabolic abnormalities are severe enough to increase mortality. Inflammatory shock constitutes the hallmark of sepsis, but also a final common pathway of any form of severe long-term tissue hypoperfusion. The pathogenesis of inflammatory shock seems to be due to circulating substances released by pathogens (e.g., bacterial endotoxins) and host immuno-inflammatory responses (e.g., changes in the production of histamine, bradykinin, serotonin, nitric oxide [NO], reactive nitrogen and oxygen species, and arachidonic acid [AA]-derived eicosanoids mainly through NO synthase, cyclooxygenase, and cytochrome P450 [CYP] pathways, and proinflammatory cytokine formation). Therefore, refractory hypotension to vasoconstrictors with end-organ hypoperfusion is a life threatening feature of inflammatory shock. This review summarizes the current knowledge regarding the role of eicosanoids derived from CYP pathway of AA in animal models of inflammatory shock syndromes with an emphasis on septic shock in addition to potential therapeutic strategies targeting specific CYP isoforms responsible for proinflammatory/anti-inflammatory mediator production.

MCPIP1 regulates RORα expression to protect against liver injury induced by lipopolysaccharide via modulation of miR-155

Liver injury plays vital roles in the development of inflammation and organ dysfunction during sepsis. MCP-1-induced protein 1 (MCPIP1), as an endoribonuclease, is a critical regulator for the maintenance of immune homeostasis. However, whether MCPIP1 participates in the septic liver injury remains unknown. The aim of this study was to investigate the role of MCPIP1 in lipopolysaccharides-induced liver injury and the underlying modulatory mechanisms. Quantitative real-time polymerase chain reaction and immunoblotting were used to determine proinflammatory cytokines, MCPIP1, retinoid-related orphan receptor α (RORα), miR-155, and related protein from nuclear factor-κB (NF-κB) pathway expression. Dual luciferase reporter assay was used to analyze whether miR-155 regulates RORα transcription. Secretion of inflammatory cytokines into sera in mice were measured by enzyme-linked immunosorbent assay. Hematoxylin and eosin staining, alanine aminotransferase, and aspartate transaminase, assay were used to evaluate liver function. We found that MCPIP1 expression was notably upregulated and significantly downregulated inflammatory cytokine secretion and NF-κB signaling activation in macrophages following exposure to lipopolysaccharide. Moreover, miR-155, lowered by MCPIP1, directly targeted on 3'-untranslated region of RORα to activate an inflammatory response. Importantly, MCPIP1 overexpression in mice alleviated septic liver injury symptoms following lipopolysaccharides stimulation. Collectively, these data highlight MCPIP1/miR-155/RORα axis as a novel modulation of inflammation in liver injury and potential therapeutic target for future research.

Leukadherin-1-Mediated Activation of CD11b Inhibits LPS-Induced Pro-inflammatory Response in Macrophages and Protects Mice Against Endotoxic Shock by Blocking LPS-TLR4 Interaction

Dysregulation of macrophage has been demonstrated to contribute to aberrant immune responses and inflammatory diseases. CD11b, expressed on macrophages, plays a critical role in regulating pathogen recognition, phagocytosis, and cell survival. In the present study, we explored the effect of leukadherin-1 (LA1), an agonist of CD11b, on regulating LPS-induced pro-inflammatory response in macrophages and endotoxic shock. Intriguingly, we found that LA1 could significantly reduce mortalities of mice and alleviated pathological injury of liver and lung in endotoxic shock. In vivo studies showed that LA1-induced activation of CD11b significantly inhibited the LPS-induced pro-inflammatory response in macrophages of mice. Moreover, LA1-induced activation of CD11b significantly inhibited LPS/IFN-γ-induced pro-inflammatory response in macrophages by inhibiting MAPKs and NF-κB signaling pathways in vitro. Furthermore, the mice injected with LA1-treated BMDMs showed fewer pathological lesions than those injected with vehicle-treated BMDMs in endotoxic shock. In addition, we found that activation of TLR4 by LPS could endocytose CD11b and activation of CD11b by LA1 could endocytose TLR4 in vitro and in vivo, subsequently blocking the binding of LPS with TLR4. Based on these findings, we concluded that LA1-induced activation of CD11b negatively regulates LPS-induced pro-inflammatory response in macrophages and subsequently protects mice from endotoxin shock by partially blocking LPS-TLR4 interaction. Our study provides a new insight into the role of CD11b in the pathogenesis of inflammatory diseases.

Leukadherin-1-Mediated Activation of CD11b Inhibits LPS-Induced Pro-inflammatory Response in Macrophages and Protects Mice Against Endotoxic Shock by Blocking LPS-TLR4 Interaction

Dysregulation of macrophage has been demonstrated to contribute to aberrant immune responses and inflammatory diseases. CD11b, expressed on macrophages, plays a critical role in regulating pathogen recognition, phagocytosis, and cell survival. In the present study, we explored the effect of leukadherin-1 (LA1), an agonist of CD11b, on regulating LPS-induced pro-inflammatory response in macrophages and endotoxic shock. Intriguingly, we found that LA1 could significantly reduce mortalities of mice and alleviated pathological injury of liver and lung in endotoxic shock. In vivo studies showed that LA1-induced activation of CD11b significantly inhibited the LPS-induced pro-inflammatory response in macrophages of mice. Moreover, LA1-induced activation of CD11b significantly inhibited LPS/IFN-γ-induced pro-inflammatory response in macrophages by inhibiting MAPKs and NF-κB signaling pathways in vitro. Furthermore, the mice injected with LA1-treated BMDMs showed fewer pathological lesions than those injected with vehicle-treated BMDMs in endotoxic shock. In addition, we found that activation of TLR4 by LPS could endocytose CD11b and activation of CD11b by LA1 could endocytose TLR4 in vitro and in vivo, subsequently blocking the binding of LPS with TLR4. Based on these findings, we concluded that LA1-induced activation of CD11b negatively regulates LPS-induced pro-inflammatory response in macrophages and subsequently protects mice from endotoxin shock by partially blocking LPS-TLR4 interaction. Our study provides a new insight into the role of CD11b in the pathogenesis of inflammatory diseases.