Hospitalization Type and Subsequent Severe Sepsis

Emergency medicine updates: Management of sepsis and septic shock

INTRODUCTION

Sepsis is a common condition associated with significant morbidity and mortality. Emergency physicians play a key role in the diagnosis and management of this condition.

OBJECTIVE

This paper evaluates key evidence-based updates concerning the management of sepsis and septic shock for the emergency clinician.

DISCUSSION

Sepsis is a life-threatening syndrome, and rapid diagnosis and management are essential. Antimicrobials should be administered as soon as possible, as delays are associated with increased mortality. Resuscitation targets include mean arterial pressure ≥ 65 mmHg, mental status, capillary refill time, lactate, and urine output. Intravenous fluid resuscitation plays an integral role in those who are fluid responsive. Balanced crystalloids and normal saline are both reasonable options for resuscitation. Early vasopressors should be initiated in those who are not fluid-responsive. Norepinephrine is the recommended first-line vasopressor, and if hypotension persists, vasopressin should be considered, followed by epinephrine. Administration of vasopressors through a peripheral 20-gauge or larger intravenous line is safe and effective. Steroids such as hydrocortisone and fludrocortisone should be considered in those with refractory septic shock.

CONCLUSION

An understanding of the recent updates in the literature concerning sepsis and septic shock can assist emergency clinicians and improve the care of these patients.

Emergency medicine updates: Evaluation and diagnosis of sepsis and septic shock

INTRODUCTION

Sepsis and septic shock are common conditions evaluated and managed in the emergency department (ED), and these conditions are associated with significant morbidity and mortality. There have been several recent updates in the literature, including guidelines, on the evaluation and diagnosis of sepsis and septic shock.

OBJECTIVE

This is the first paper in a two-part series that provides emergency clinicians with evidence-based updates concerning sepsis and septic shock. This first paper focuses on evaluation and diagnosis of sepsis and septic shock.

DISCUSSION

The evaluation, diagnosis, and management of sepsis have evolved since the first definition in 1991. Current guidelines emphasize rapid diagnosis to improve patient outcomes. However, scoring systems have conflicting data for diagnosis, and sepsis should be considered in any patient with infection and abnormal vital signs, evidence of systemic inflammation (e.g., elevated white blood cell count or C-reactive protein), or evidence of end-organ dysfunction. The clinician should consider septic shock in any patient with infection and hypotension despite volume resuscitation or who require vasopressors to maintain a mean arterial pressure ≥ 65 mmHg. There are a variety of sources of sepsis but the most common include pulmonary, urinary tract, abdomen, and skin/soft tissue. Examples of other less common etiologies include the central nervous system (e.g., meningitis, encephalitis), spine (e.g., spinal epidural abscess, osteomyelitis), cardiac (e.g., endocarditis), and joints (e.g., septic arthritis). Evaluation may include biomarkers such as procalcitonin, C-reactive protein, and lactate, but these should not be used in isolation to exclude sepsis. Imaging is a key component of evaluation and should be based on the suspected source.

CONCLUSION

There have been several recent updates in the literature including guidelines concerning sepsis and septic shock; an understanding of these updates can assist emergency clinicians and improve the care of these patients.

Interaction, diagnosis, and treatment of lung microbiota-NLRP3 inflammasome-target organ axis in sepsis

Sepsis is defined as a life-threatening condition caused by a dysregulated host response to infection, leading to multi-organ dysfunction, and representing a significant global health burden. The progression of sepsis is closely linked to disruptions in lung microbiota, including bacterial translocation, impaired barrier function, and local microenvironmental disturbances. Conversely, the worsening of sepsis exacerbates lung microbiota imbalances, contributing to multi-organ dysfunction. Recent culture-independent microbiological techniques have unveiled the complexity of the respiratory tract microbiome, necessitating a reassessment of the interactions between the host, microbes, and pathogenesis in sepsis. This review synthesizes current insights into the causes of microbiota dysbiosis and the regulatory mechanisms of the NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome, as well as their interactions during sepsis and sepsis-induced organ dysfunction. In addition, we summarize novel diagnostic and therapeutic approaches from the current study that may offer promising prospects for the management of sepsis.

Empirical antibiotic therapy for sepsis: save the anaerobic microbiota

Antibiotics are fundamental in sepsis management; however, the optimal empirical treatment remains debated. Despite anaerobes rarely being the causative pathogen of sepsis, antibiotics targeting them are frequently used, which might lead to unintended consequences. Multiple studies have shown that depletion of commensal anaerobic gut microbes by anti-anaerobic antibiotics influences systemic immunity and is associated with increased mortality in patients with sepsis. However, this knowledge has not yet been translated into clinical practice. When considering empirical coverage of anaerobic pathogens in sepsis, most physicians advocate for a better-safe-than-sorry approach. In this Viewpoint, we argue that anti-anaerobic antibiotics could often result in being sorry rather than safe. We provide an overview of the limited necessity of anaerobic coverage and the potential detrimental effects of anaerobic depletion in sepsis. We aim to raise anaerobic awareness to reduce the unnecessary use of anti-anaerobic antibiotics in empirical sepsis treatment and improve patient outcomes.

Is intestinal colonization with multidrug-resistant Enterobacterales associated with higher rates of nosocomial Enterobacterales bloodstream infections?

OBJECTIVES

Intestinal colonization with multidrug-resistant Enterobacterales (MDRE-IC) increases the risk of MDRE bloodstream infection (BSI). However, its impact on the overall risk of nosocomial Enterobacterales bloodstream infections (nE-BSIs) remains unclear. This study aimed to determine this risk and identify associated factors in hospitalized patients.

DESIGN

This retrospective cohort study at a 3200-bed tertiary institution including patients hospitalized in 2019 who underwent MDRE rectal swab (RS) screening. Inclusion criteria were age ≥18 years, first RS in 2019, follow-up ≥7 days, and Enterobacterales BSIs >48 hours after RS. The primary outcome was the first nE-BSI during the follow-up period, analyzed using a Cox model.

RESULTS

Among 7006 patients, 817 (11.9%) had MDRE-IC. Most were male and primarily hospitalized in acute wards. nE-BSIs occurred in 433 (6.1%) patients and were more frequent in patients with MDRE-IC than the non-colonized group (adjusted hazard ratio [aHR] = 1.78, 95% confidence interval [CI]: 1.40-2.26). Intestinal colonization with extended-spectrum β-lactamase-producing and carbapenemase-resistant Enterobacterales showed similar risks for Enterobacterales BSI onset: aHR = 1.73 (95% CI: 1.33-2.24) and aHR = 2.02 (95% CI: 1.27-3.22), respectively.

CONCLUSIONS

In hospitalized patients, MDRE-IC is associated with a higher rate of nE-BSI than those without MDRE-IC, underscoring the urgent need for improved infection prevention and control measures, as well as optimized antibiotic use to mitigate this risk.

The weekend effect in critically ill patients with severe infections in Japanese intensive care units: a multicenter retrospective cohort study

Background

Reduced or delayed access to medical resources on weekends could lead to worsening outcomes, in critically ill infected patients requiring intensive care unit (ICU) admission.

Objective

To investigate the "weekend effect," on critically ill infected patients in Japanese ICUs for the first time.

Design

Multicenter retrospective cohort study.

Methods

We examined data from Japanese ICU patients participating in the DIANA study, a multicenter international observational cohort study. This prospective investigation enrolled critically ill patients with infections admitted to the ICU. The primary endpoint was successful discharge from the ICU within 28 days of admission. Outcome measures were evaluated through both univariate and covariate Cox regression analyses, providing hazard ratios (HRs) along with estimated 95% confidence intervals (CIs).

Results

Out of the 276 patients enrolled in the DIANA study across 31 facilities, 208 patients (75.4%) meeting the inclusion criteria were included in the analysis. The weekday ICU admission group comprised 156 patients (75.0%), while the weekend ICU admission group comprised 52 patients (25.0%). In the multivariate Cox regression analysis, there were no statistically significant differences observed in the rates of ICU discharge alive within 28 days and 14 days (28 days, HR: 0.94, 95% CI: 0.63-1.40; 14 days, HR: 0.97, 95% CI: 0.64-1.48). Furthermore, the overall ICU mortality rates at 28 days and 14 days after ICU admission did not show statistical significance between patients admitted on weekends and those admitted on weekdays (ICU mortality, 28 days: 13.5% vs 11.5%, p = 0.806; 14 days: 7.7% vs 10.9%, p = 0.604).

Conclusion

The rates of ICU discharge alive within 28 days after ICU admission did not differ significantly between weekday and weekend admissions, both in the unadjusted and adjusted analyses. Moreover, further well-designed studies are warranted to thoroughly assess this effect.

Gut Microbiota and Liver Dysfunction in Sepsis: The Role of Inflammatory Mediators and Therapeutic Approaches

Sepsis is a life-threatening complication caused by an uncontrolled immune response to infection that can lead to multi-organ dysfunction, including liver injury. Recent research has shown the critical role of gut microbiota in sepsis pathogenesis, with the gut-liver axis playing a crucial role in disease progression. Mechanisms such as the disruption of the gut barrier and liver injury pathways mediated by cytokines, chemokines, adhesion molecules, hydrogen sulfide (H2S). and substance P (SP) have been the focus of recent studies. Some potential biomarkers and gut microbiota-targeted therapies have shown promise as emerging tools for predicting and managing sepsis. This review describes the role of the gut-liver axis in sepsis and the potential of microbiota-targeted therapies and biomarker-driven interventions to improve sepsis outcomes.

Gut Microbiota Dysbiosis Facilitates Susceptibility to Bloodstream Infection

To study the role of intestinal flora in the development of bloodstream infections (BSIs). 42 patients and 19 healthy controls (HCs) were screened into the study and their intestinal flora was measured by 16S rRNA gene sequencing. The bacterial diversity was significantly lower in the BSI group compared with that in the HCs (P < 0.001), and beta diversity was significantly differentiated between the two groups (PERMANOVA, P = 0.001). The four keystone species [Roseburia, Faecalibacterium, Prevotella, and Enterococcus (LDA > 4)] differed significantly between the two groups. Dysbiosis of fecal microbial ecology is a common condition present in patients with BSI. The proliferation of certain pathogens or reduction of SCFA-producing bacteria would cause susceptibility to BSI.

Gut Microbiome in Human Melioidosis: Composition and Resistome Dynamics from Diagnosis to Discovery

Background

Melioidosis, attributable to the soil-dwelling bacterium Burkholderia pseudomallei, stands as a paramount global health challenge, necessitating extended courses of antibiotics. While murine studies identified the gut microbiota as a modulator of bacterial dissemination during melioidosis, the human intestinal microbiota during melioidosis remains uncharacterized. Here, we characterized gut microbiota composition and antimicrobial resistance (AMR) genes at diagnosis, during treatment, and postdischarge for melioidosis. We hypothesized that the gut microbiota of melioidosis patients would be extensively distorted.

Methods

In this prospective observational cohort, stool samples of patients with culture-confirmed melioidosis admitted to a tertiary care hospital in India were collected at diagnosis, 14 days after diagnosis, or discharge (whichever occurred first) and at 6 months postinfection. Family members or neighbors served as community controls. The gut microbiota and resistome were profiled by shotgun metagenomic sequencing.

Results

We longitudinally analyzed the gut microbiota of 70 fecal samples from 28 patients and 16 community controls. At diagnosis, the gut microbiota of patients differed from that of controls, characterized by high abundances of potentially pathogenic bacteria, a loss of butyrate-producing bacteria, and higher levels of AMR genes. Microbiota composition and resistome remained different from community controls at 6 months, driven by total antibiotic exposure. During hospitalization, gut microbiota profiles were associated with secondary Klebsiella pneumoniae infections.

Conclusions

This first study on gut microbiota composition and resistome in human melioidosis showed extensive disruptions during hospitalization, with limited signs of restoration 6 months postinfection. Given the adverse outcomes linked with microbiome perturbations, limiting microbiota disruptions or using microbiota-restorative therapies (eg, butyrate-producing probiotics) may be beneficial.

Predicting Neutropenic Sepsis in Patients with Hematologic Malignancy: A Retrospective Case-Control Study

Neutropenic sepsis (NS) is one of the leading causes of death among patients with hematologic malignancies. Identifying its predictive factors is fundamental for early detection. Few studies have evaluated the predictive factors in relation to microbial infection confirmation, which is clinically important for initiating sepsis treatment. This study aimed to determine whether selected biomarkers (i.e., body temperature, C-reactive protein, albumin, procalcitonin), treatment-related characteristics (i.e., diagnosis, duration of neutropenia, treatment modality), and infection-related characteristics (i.e., infection source, causative organisms) can predict NS in patients with hematologic malignancies. We also aimed to identify the optimal predictive cutoff points for these parameters. This retrospective case-control study used the data from a total of 163 patients (58 in the sepsis group and 105 in the non-sepsis group). We collected data with reference to the day of specimen collection, with which microbial infection was confirmed. Multiple logistic regression was used to determine predictive risk factors and the area under the curve (AUC) of the receiver operating characteristic for the optimal predictive cutoff points. The independent predictors of NS were average body temperature during a fever episode and procalcitonin level. The odds for NS rose by 9.97 times with every 1°C rise in average body temperature (95% confidence interval, CI [1.33, 75.05]) and by 2.09 times with every 1 ng/mL rise in the procalcitonin level (95% CI [1.08, 4.04]). Average body temperature (AUC = 0.77, 95% CI [0.68, 0.87]) and procalcitonin levels (AUC = 0.71, 95% CI [0.59, 0.84]) have fair accuracy for predicting NS, with the optimal cutoff points of 37.9°C and 0.55 ng/mL, respectively. This study found that average body temperature during a fever episode and procalcitonin are useful in predicting NS. Thus, nurses should carefully monitor body temperature and procalcitonin levels in patients with hematologic malignancies to detect the onset of NS.

Investigating the effect of synbiotic supplementation on inflammatory indices in critically ill septic children: a protocol study for randomized control trial

BACKGROUND

Sepsis, a severe inflammatory response to infection, is a global health priority due to its high mortality and long-term disability rates. Its pathophysiology involves both inflammation and immune suppression. Managing sepsis requires significant healthcare resources and expenditure, with sepsis being a leading cause of hospital costs. Gut microbiotas play a crucial role in sepsis, and probiotics show promise in managing it by restoring microbial balance. Despite advances, targeted therapies for sepsis remain elusive, necessitating innovative approaches such as probiotic therapy.

METHOD

Fifty-four eligible patients with sepsis will be randomly assigned to either the synbiotic or placebo group. The synbiotic supplement, KidiLact, comprises ten probiotic strains and prebiotic fructooligosaccharides. Participants will receive two sachets daily for 7 days, mixed with sterile water and administered orally or via gavage. Inflammatory factors including interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) will be evaluated. Anthropometric measurements, nutritional assessment, biochemical analysis, and clinical evaluation will be conducted to assess treatment outcomes. Statistical analysis will be performed to compare results between the two groups, employing SPSS version 19 with a significance level of P < .05.

CONCLUSION

This randomized clinical trial aims to evaluate synbiotic supplementation effects on inflammatory markers and clinical outcomes in pediatric sepsis patients in the pediatric intensive care unit (PICU). Probiotics have shown promise in reducing proinflammatory cytokines like IL-6, TNF-α, and CRP, which are vital in the inflammatory response. Synbiotics can enhance gut integrity, preventing pathogen translocation and reducing inflammation. If our expectations regarding the effects of probiotics are correct, we can use them as a cost-effective supplement to improve the condition of pediatric sepsis in hospitals.

TRIAL REGISTRATION

IRCT,IRCT20230523058266N1 Registered 30 October 2023, https://irct.behdasht.gov.ir/trial/71397 .

The Gut Microbiome in Sepsis: From Dysbiosis to Personalized Therapy

Sepsis is a complex clinical syndrome characterized by an uncontrolled inflammatory response to an infection that may result in septic shock and death. Recent research has revealed a crucial link between sepsis and alterations in the gut microbiota, showing that the microbiome could serve an essential function in its pathogenesis and prognosis. In sepsis, the gut microbiota undergoes significant dysbiosis, transitioning from a beneficial commensal flora to a predominance of pathobionts. This transformation can lead to a dysfunction of the intestinal barrier, compromising the host's immune response, which contributes to the severity of the disease. The gut microbiota is an intricate system of protozoa, fungi, bacteria, and viruses that are essential for maintaining immunity and metabolic balance. In sepsis, there is a reduction in microbial heterogeneity and a predominance of pathogenic bacteria, such as proteobacteria, which can exacerbate inflammation and negatively influence clinical outcomes. Microbial compounds, such as short-chain fatty acids (SCFAs), perform a crucial task in modulating the inflammatory response and maintaining intestinal barrier function. However, the role of other microbiota components, such as viruses and fungi, in sepsis remains unclear. Innovative therapeutic strategies aim to modulate the gut microbiota to improve the management of sepsis. These include selective digestive decontamination (SDD), probiotics, prebiotics, synbiotics, postbiotics, and fecal microbiota transplantation (FMT), all of which have shown potential, although variable, results. The future of sepsis management could benefit greatly from personalized treatment based on the microbiota. Rapid and easy-to-implement tests to assess microbiome profiles and metabolites associated with sepsis could revolutionize the disease's diagnosis and management. These approaches could not only improve patient prognosis but also reduce dependence on antibiotic therapies and promote more targeted and sustainable treatment strategies. Nevertheless, there is still limited clarity regarding the ideal composition of the microbiota, which should be further characterized in the near future. Similarly, the benefits of therapeutic approaches should be validated through additional studies.

Effect of mixed probiotics on pulmonary flora in patients with mechanical ventilation: an exploratory randomized intervention study

OBJECTIVE

The study objective was to investigate the effect of mixed probiotics on the diversity of the pulmonary flora in critically ill patients requiring mechanical ventilation by analysing the changes in lung microbes.

METHODS

24 adult critically ill patients who needed mechanical ventilation in our hospital were randomly divided into a probiotic group and a control group. Then, the probiotic group was given Live Combined Bifidobacterium, Lactobacillus and Enterococcus Capsules, Oral (Bifico) by nasal feeding within 24 h after mechanical ventilation. Bronchoalveolar lavage fluid (BALF) and venous blood were collected within 24 h after mechanical ventilation and on the 5th day after mechanical ventilation, and the treatment status of patients (mechanical ventilation time, 28-day survival), measured cytokine levels (IL-1 β, IL-6, IL-8, IL-17A) and changes in pulmonary microorganisms were observed.

RESULTS

The microbial diversity of BALF samples decreased in the control group, and there was no significant difference in the probiotic group. Species difference analysis showed that among the three probiotics (Bifidobacterium, Lactobacillus, Enterococcus) used for intervention, Lactobacillus caused significant differences in BALF in the control group. Clinical factor association analysis displayed significant associations with IL-17A levels in both blood and BALF.

CONCLUSION

Mechanical ventilation can cause a decline in pulmonary microbial diversity, which can be improved by administering mixed probiotics.

Association between butyrate-producing gut bacteria and the risk of infectious disease hospitalisation: results from two observational, population-based microbiome studies

BACKGROUND

Microbiota alterations are common in patients hospitalised for severe infections, and preclinical models have shown that anaerobic butyrate-producing gut bacteria protect against systemic infections. However, the relationship between microbiota disruptions and increased susceptibility to severe infections in humans remains unclear. We investigated the relationship between gut microbiota and the risk of future infection-related hospitalisation in two large population-based cohorts.

METHODS

In this observational microbiome study, gut microbiota were characterised using 16S rRNA gene sequencing in independent population-based cohorts from the Netherlands (HELIUS study; derivation cohort) and Finland (FINRISK 2002 study; validation cohort). HELIUS was conducted in Amsterdam, Netherlands, and included adults (aged 18-70 years at inclusion) who were randomly sampled from the municipality register of Amsterdam. FINRISK 2002 was conducted in six regions in Finland and is a population survey that included a random sample of adults (aged 25-74 years). In both cohorts, participants completed questionnaires, underwent a physical examination, and provided a faecal sample at inclusion (Jan 3, 2013, to Nov 27, 2015, for HELIUS participants and Jan 21 to April 19, 2002, for FINRISK participants. For inclusion in our study, a faecal sample needed to be provided and successfully sequenced, and national registry data needed to be available. Primary predictor variables were microbiota composition, diversity, and relative abundance of butyrate-producing bacteria. Our primary outcome was hospitalisation or mortality due to any infectious disease during 5-7-year follow-up after faecal sample collection, based on national registry data. We examined associations between microbiota and infection risk using microbial ecology and Cox proportional hazards.

FINDINGS

We profiled gut microbiota from 10 699 participants (4248 [39·7%] from the derivation cohort and 6451 [60·3%] from the validation cohort). 602 (5·6%) participants (152 [3·6%] from the derivation cohort; 450 [7·0%] from the validation cohort) were hospitalised or died due to infections during follow-up. Gut microbiota composition of these participants differed from those without hospitalisation for infections (derivation p=0·041; validation p=0·0002). Specifically, higher relative abundance of butyrate-producing bacteria was associated with a reduced risk of hospitalisation for infections (derivation cohort cause-specific hazard ratio 0·75 [95% CI 0·60-0·94] per 10% increase in butyrate producers, p=0·013; validation cohort 0·86 [0·77-0·96] per 10% increase, p=0·0077). These associations remained unchanged following adjustment for demographics, lifestyle, antibiotic exposure, and comorbidities.

INTERPRETATION

Gut microbiota composition, specifically colonisation with butyrate-producing bacteria, was associated with protection against hospitalisation for infectious diseases in the general population across two independent European cohorts. Further studies should investigate whether modulation of the microbiome can reduce the risk of severe infections.

FUNDING

Amsterdam UMC, Porticus, National Institutes of Health, Netherlands Organisation for Health Research and Development (ZonMw), and Leducq Foundation.

Antimicrobial resistance in intensive care patients hospitalized with SEPSIS: a comparison between the COVID-19 pandemic and pre-pandemic era

Introduction

Coronavirus disease 2019 (COVID-19) is a highly contagious viral illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It has had a dramatic effect on the world, resulting in millions of deaths worldwide and causing drastic changes in daily life. A study reported that septic complications were associated with high mortality in COVID-19 patients. This study aimed to evaluate how the COVID-19 pandemic changed the pre-pandemic and post-pandemic prevalence of sepsis in ICUs and to evaluate the different risk factors associated with mortality and the different diffusion of microorganisms and their resistance.

Materials and methods

We conducted a single-center retrospective observational clinical study, observing all patients in the ICU of the SS Annunziata Hospital in Chieti (Italy) who were diagnosed with sepsis and had a bacterial isolate from their blood culture. Sepsis was diagnosed by SEPSIIS III criteria. We enrolled all in-patients in the ICU from January 2018 to December 2021. We divided the patients into three groups: (1) non-pandemic period (Np) hospitalized in 2018-2019, (2) pandemic period (Pp)-COVID hospitalized in 2020-2021 with a diagnosis of COVID-19, and (3) Pp-non-COVID patients hospitalized in 2020-2021 without a diagnosis of COVID-19.

Results

From January 2018 to December 2021, 1,559 patients were admitted to the ICU, of which 211 patients [36 (17.1%) in 2018, 52 (24.6%) in 2019, 73 (34.6%) in 2020, and 50 (23.7%) in 2021, respectively] met the selection criteria: 88 patients in period Np, 67 patients in Pp without COVID-19, and 56 patients Pp with COVID-19. The overall mortality of these patients was high (65.9% at 30 days in Np), but decreased during the Pp (60.9%): Pp-non-COVID was 56.7% vs. Pp-COVID 66.1%, with a statistically significant association with APACHE III score (OR 1.08, 95%CI 1.04-1.12, p < 0.001), SOFA score (OR 1.12, 95%CI 1.03-1.22, p = 0.004), and age (OR 1.04, 95%CI 1.02-1.07, p < 0.0001). Between the Np vs. Pp periods, we observed an increase in a few Gram-positive bacteria such as S. capitis (1 pt. -0.9% vs. 14 pt. -7.65%- p = 0.008), S. epidermidis, Streptococcus spp., and E. faecalis, as well as a decrease in a case of blood culture positive for S. aureus, S. hominis, and E. faecium. In Gram-negative bacteria, we observed an increase in cases of Acinetobacter spp. (Np 6 pt. -5.1%- vs. Pp 20 pt. -10.9%, p = 0.082), and Serratia spp., while cases of sepsis decreased from E. faecium (Np 11 pt. -9.4%- vs. Pp 7 pt. -3.8%, p = 0.047), and Enterobacter spp., S. haemolyticus, S. maltophilia, Proteus spp., and P. aeruginosa have not changed. Finally, we found that resistance to OXA-48 (p = 0.040), ESBL (p = 0.002), carbapenems (p = 0.050), and colistin (p = 0.003) decreased with time from Np to Pp, particularly in Pp-COVID.

Conclusion

This study demonstrated how the COVID-19 pandemic changed the prevalence of sepsis in the ICU. It emerged that the risk factors associated with mortality were APACHE and SOFA scores, age, and, above all, the presence of ESBL-producing bacteria. Despite this, during the pandemic phase, we have observed a significant reduction in the emergence of resistant germs compared to the pre-pandemic phase.

The Interplay between Antibiotics and the Host Immune Response in Sepsis: From Basic Mechanisms to Clinical Considerations: A Comprehensive Narrative Review

Sepsis poses a significant global health challenge due to immune system dysregulation. This narrative review explores the complex relationship between antibiotics and the immune system, aiming to clarify the involved mechanisms and their clinical impacts. From pre-clinical studies, antibiotics exhibit various immunomodulatory effects, including the regulation of pro-inflammatory cytokine production, interaction with Toll-Like Receptors, modulation of the P38/Pmk-1 Pathway, inhibition of Matrix Metalloproteinases, blockade of nitric oxide synthase, and regulation of caspase-induced apoptosis. Additionally, antibiotic-induced alterations to the microbiome are associated with changes in systemic immunity, affecting cellular and humoral responses. The adjunctive use of antibiotics in sepsis patients, particularly macrolides, has attracted attention due to their immune-regulatory effects. However, there are limited data comparing different types of macrolides. More robust evidence comes from studies on community-acquired pneumonia, especially in severe cases with a hyper-inflammatory response. While studies on septic shock have shown mixed results regarding mortality rates and immune response modulation, conflicting findings are also observed with macrolides in acute respiratory distress syndrome. In conclusion, there is a pressing need to tailor antibiotic therapy based on the patient's immune profile to optimize outcomes in sepsis management.

The causality of gut microbiota on onset and progression of sepsis: a bi-directional Mendelian randomization analysis

Background

Several observational studies have proposed a potential link between gut microbiota and the onset and progression of sepsis. Nevertheless, the causality of gut microbiota and sepsis remains debatable and warrants more comprehensive exploration.

Methods

We conducted a two-sample Mendelian randomization (MR) analysis to test the causality between gut microbiota and the onset and progression of sepsis. The genome-wide association study (GWAS) summary statistics for 196 bacterial traits were extracted from the MiBioGen consortium, whereas the GWAS summary statistics for sepsis and sepsis-related outcomes came from the UK Biobank. The inverse-variance weighted (IVW) approach was the primary method used to examine the causal association. To complement the IVW method, we utilized four additional MR methods. We performed a series of sensitivity analyses to examine the robustness of the causal estimates.

Results

We assessed the causality of 196 bacterial traits on sepsis and sepsis-related outcomes. Genus Coprococcus2 [odds ratio (OR) 0.81, 95% confidence interval (CI) (0.69-0.94), p = 0.007] and genus Dialister (OR 0.85, 95% CI 0.74-0.97, p = 0.016) had a protective effect on sepsis, whereas genus Ruminococcaceae UCG011 (OR 1.10, 95% CI 1.01-1.20, p = 0.024) increased the risk of sepsis. When it came to sepsis requiring critical care, genus Anaerostipes (OR 0.49, 95% CI 0.31-0.76, p = 0.002), genus Coprococcus1 (OR 0.65, 95% CI 0.43-1.00, p = 0.049), and genus Lachnospiraceae UCG004 (OR 0.51, 95% CI 0.34-0.77, p = 0.001) emerged as protective factors. Concerning 28-day mortality of sepsis, genus Coprococcus1 (OR 0.67, 95% CI 0.48-0.94, p = 0.020), genus Coprococcus2 (OR 0.48, 95% CI 0.27-0.86, p = 0.013), genus Lachnospiraceae FCS020 (OR 0.70, 95% CI 0.52-0.95, p = 0.023), and genus Victivallis (OR 0.82, 95% CI 0.68-0.99, p = 0.042) presented a protective effect, whereas genus Ruminococcus torques group (OR 1.53, 95% CI 1.00-2.35, p = 0.049), genus Sellimonas (OR 1.25, 95% CI 1.04-1.50, p = 0.019), and genus Terrisporobacter (OR 1.43, 95% CI 1.02-2.02, p = 0.040) presented a harmful effect. Furthermore, genus Coprococcus1 (OR 0.42, 95% CI 0.19-0.92, p = 0.031), genus Coprococcus2 (OR 0.34, 95% CI 0.14-0.83, p = 0.018), and genus Ruminiclostridium6 (OR 0.43, 95% CI 0.22-0.83, p = 0.012) were associated with a lower 28-day mortality of sepsis requiring critical care.

Conclusion

This MR analysis unveiled a causality between the 21 bacterial traits and sepsis and sepsis-related outcomes. Our findings may help the development of novel microbiota-based therapeutics to decrease the morbidity and mortality of sepsis.

Analysis of fecal microbiota and related clinical indicators in ICU patients with sepsis

Background

To analyze the characteristics of fecal microbiota disturbance in the intensive care unit (ICU) patients with sepsis and the correlation with related clinical indicators.

Methods

This study included 31 patients with sepsis admitted to the emergency ICU ward between September 2019 and December 2021. They were divided into Group without septic shock (ND_NS group, 7 cases) and Group with septic shock (ND_S group, 24 cases) according to the presence or absence of septic shock. Furthermore, we divided these 31 sepsis patients into Clinical Improvement group (21 cases) and Death or DAMA group (10 cases) based on clinical outcome, 15 cases of Physical Examiner recruited in the same period were included as control group: ND_HC group (15 cases). The fecal samples of the patients with sepsis within 24 h of admission and random fecal samples of the control group were collected and analyzed by 16S rDNA gene sequencing used for the analysis of fecal microbiota. At the same time, the relevant clinical data of these patients with sepsis were also collected for analysis.

Results

There were 15 cases with drug-resistant bacteria in the ND_S group and only 2 cases in the ND_NS group (P = 0.015). There were significant differences in APACHE II score, length of ICU stay, lactate level, and oxygenation index of patients between the Death or DAMA group and Clinical Improvement group (all P < 0.05). For phylum level, the abundance of Firmicutes, Actinobacteria, and Bacteroidetes decreased in the ND group compared with the ND_HC group, while the abundance of Proteobacteria increased (P < 0.05). For genus level, the relative abundance of Escherichia-Shigella and Klebsiella were significantly increased in the ND group compared with the ND_HC group (P < 0.05). The top six genera in relative abundance in the ND_S group were Escherichia-Shigella, Enterococcus, Bifidobacterium, Lactobacillus, Akkermansia, and Klebsiella. Compared with the Clinical Improvement group, the relative abundance of Escherichia-Shigella and Klebsiella in the Death or DAMA group showed an increasing trend with no significant significance, while the relative abundance of Enterococcus and Faecalibacterium decreased in the Death or DAMA group (P < 0.05). Alpha diversity analysis showed that compared with the ND_HC group, the alpha diversity of the fecal microbiota in the ND group decreased. There were significant differences in the Observed_species index, Chao1 index, and ACE index of patients between the ND_HC group and ND group (all P < 0.05). Moreover, compared with the ND_NS group, the Alpha diversity of the ND_S group was more abundant. PCoA analysis showed significant differences in microbial community structure between the ND group and ND_HC group (P = 0.001). There also were significant differences in microbial community structure between the ND_S group and ND_NS group (P = 0.008). LEfSe analysis showed that compared with the ND_HC group, there were significant differences in the species of the ND group, including Enterobacteriaceae, Escherichia-Shigella, Enterococcus, Elizabethkingia, and Family_XIII_AD3011_group.

Conclusions

ICU patients with sepsis suffered intestinal microecological disturbances with significantly decreased abundance of fecal microbiota, diversity, and beneficial symbiotic bacteria. For these patients, the ratio of pathogenic bacteria, including Escherichia-Shigella and Klebsiella increased and became the main bacterial genus in some samples. Moreover, the increasing trend of these two pathogenic bacteria may be correlated with the development of septic shock and the risk of death in patients with sepsis.

Reframing sepsis immunobiology for translation: towards informative subtyping and targeted immunomodulatory therapies

Sepsis is a common and deadly condition. Within the current model of sepsis immunobiology, the framing of dysregulated host immune responses into proinflammatory and immunosuppressive responses for the testing of novel treatments has not resulted in successful immunomodulatory therapies. Thus, the recent focus has been to parse observable heterogeneity into subtypes of sepsis to enable personalised immunomodulation. In this Personal View, we highlight that many fundamental immunological concepts such as resistance, disease tolerance, resilience, resolution, and repair are not incorporated into the current sepsis immunobiology model. The focus for addressing heterogeneity in sepsis should be broadened beyond subtyping to encompass the identification of deterministic molecular networks or dominant mechanisms. We explicitly reframe the dysregulated host immune responses in sepsis as altered homoeostasis with pathological disruption of immune-driven resistance, disease tolerance, resilience, and resolution mechanisms. Our proposal highlights opportunities to identify novel treatment targets and could enable successful immunomodulation in the future.

Golden bifid treatment regulates gut microbiota and serum metabolites to improve myocardial dysfunction in cecal ligation and puncture-induced sepsis mice

Myocardial damage is a major consequence and a significant contributor to death in cases of sepsis, a severe infection characterized by a distinct inflammatory response and a potential threat to the patient's life. Recently, the effects of intestinal microbiota and serum metabolites on sepsis have garnered increasing attention. Herein, the effects of golden bifid treatment upon cecal ligation and puncture (CLP)-induced sepsis in mice as a model for myocardial dysfunction were explored. Our results demonstrated that golden bifid treatment partially improved myocardial dysfunction and apoptosis, cardiac inflammation and oxidative stress, and intestinal mucosal permeability and barrier dysfunction in CLP-induced sepsis mice. The intestinal microbiota diversity and abundance were also altered within sepsis mice and improved by golden bifid treatment. Mucispirillum schaedleri, Acinetobacter baumannii and Lactobacullus intestinalis were significantly correlated with heart damage markers, inflammatory factors, or oxidative stress indicators. Serum differential metabolite levels were also significantly correlated with these parameters. Altogether, golden bifid treatment might be an underlying approach for treating sepsis-induced myocardial dysfunction and highlight the underlying effect of intestinal microbiota and serum metabolites on the pathogenesis and treatment of sepsis-triggered myocardial dysfunction.

IRF3 function and immunological gaps in sepsis

Lipopolysaccharide (LPS) induces potent cell activation via Toll-like receptor 4/myeloid differentiation protein 2 (TLR4/MD-2), often leading to septic death and cytokine storm. TLR4 signaling is diverted to the classical acute innate immune, inflammation-driving pathway in conjunction with the classical NF-κB pivot of MyD88, leading to epigenetic linkage shifts in nuclear pro-inflammatory transcription and chromatin structure-function; in addition, TLR4 signaling to the TIR domain-containing adapter-induced IFN-β (TRIF) apparatus and to nuclear pivots that signal the association of interferons alpha and beta (IFN-α and IFN-β) with acute inflammation, often coupled with oxidants favor inhibition or resistance to tissue injury. Although the immune response to LPS, which causes sepsis, has been clarified in this manner, there are still many current gaps in sepsis immunology to reduce mortality. Recently, selective agonists and inhibitors of LPS signals have been reported, and there are scattered reports on LPS tolerance and control of sepsis development. In particular, IRF3 signaling has been reported to be involved not only in sepsis but also in increased pathogen clearance associated with changes in the gut microbiota. Here, we summarize the LPS recognition system, main findings related to the IRF3, and finally immunological gaps in sepsis.

The human gut microbiome in critical illness: disruptions, consequences, and therapeutic frontiers

With approximately 39 trillion cells and over 20 million genes, the human gut microbiome plays an integral role in both health and disease. Modern living has brought a widespread use of processed food and beverages, antimicrobial and immunomodulatory drugs, and invasive procedures, all of which profoundly disrupt the delicate homeostasis between the host and its microbiome. Of particular interest is the human gut microbiome, which is progressively being recognized as an important contributing factor in many aspects of critical illness, from predisposition to recovery. Herein, we describe the current understanding of the adverse impacts of standard intensive care interventions on the human gut microbiome and delve into how these microbial alterations can influence patient outcomes. Additionally, we explore the potential association between the gut microbiome and post-intensive care syndrome, shedding light on a previously underappreciated avenue that may enhance patient recuperation following critical illness. There is an impending need for future epidemiological studies to encompass detailed phenotypic analyses of gut microbiome perturbations. Interventions aimed at restoring the gut microbiome represent a promising therapeutic frontier in the quest to prevent and treat critical illnesses.

Gut microbiota and sepsis and sepsis-related death: a Mendelian randomization investigation

Background

It is unclear what the causal relationship is between the gut microbiota and sepsis. Therefore, we employed Mendelian randomization (MR) to determine whether a causal link exists between the two.

Methods

This study used publicly available genome-wide association studies (GWAS) summary data of gut microbiota, sepsis, sepsis (critical care), and sepsis (28-day death in critical care) to perform a two-sample MR analysis. To ensure the robustness of the results, we also conducted a sensitivity analysis.

Results

For sepsis susceptibility, inverse variance weighted (IVW) estimates revealed that Victivallales (OR = 0.86, 95% CI, 0.78-0.94, p = 0.0017) was protective against sepsis, while Lentisphaerae (OR = 0.89, 95% CI, 0.80-0.99), Gammaproteobacteria (OR = 1.37, 95% CI, 1.08-1.73), Clostridiaceae1 (OR = 1.21, 95% CI, 1.04-1.40), RuminococcaceaeUCG011 (OR = 1.10, 95% CI, 1.01-1.20), Dialister (OR = 0.85, 95% CI, 0.74-0.97), and Coprococcus2 (OR = 0.81, 95% CI, 0.69-0.94) presented a suggestive association with the development of sepsis (all p < 0.05). For sepsis (critical care), IVW estimates indicated that Lentisphaerae (OR = 0.70, 95% CI, 0.53-0.93), Victivallales (OR = 0.67, 95% CI, 0.50-0.91), Anaerostipes (OR = 0.49, 95% CI, 0.31-0.76), LachnospiraceaeUCG004 (OR = 0.51, 95% CI, 0.34-0.77), and Coprococcus1 (OR = 0.66, 95% CI, 0.44-0.99) showed a suggestive negative correlation with sepsis (critical care) (all p < 0.05). For sepsis (28-day death in critical care), IVW estimates suggested that four bacterial taxa had a normally significant negative correlation with the risk of sepsis-related death, including Victivallales (OR = 0.54, 95% CI, 0.30-0.95), Coprococcus2 (OR = 0.34, 95% CI, 0.14-0.83), Ruminiclostridium6 (OR = 0.43, 95% CI, 0.22-0.83), and Coprococcus1 (OR = 0.45, 95% CI, 0.21-0.97), while two bacterial taxa were normally significantly positively linked to the risk of sepsis-related death, namely, Mollicutes (OR = 2.03, 95% CI, 1.01-4.08) and Bacteroidales (OR = 2.65, 95% CI, 1.18-5.96) (all p < 0.05). The robustness of the above correlations was verified by additional sensitivity analyses.

Conclusion

This MR research found that several gut microbiota taxa were causally linked to the risk of sepsis, sepsis in critical care, and sepsis-related 28-day mortality in critical care.

Gut microbiome dynamics and associations with mortality in critically ill patients

BACKGROUND

Critical illness and care within the intensive care unit (ICU) leads to profound changes in the composition of the gut microbiome. The impact of such changes on the patients and their subsequent disease course remains uncertain. We hypothesized that specific changes in the gut microbiome would be more harmful than others, leading to increased mortality in critically ill patients.

METHODS

This was a prospective cohort study of critically ill adults in the ICU. We obtained rectal swabs from 52 patients and assessed the composition the gut microbiome using 16 S rRNA gene sequencing. We followed patients throughout their ICU course and evaluated their mortality rate at 28 days following admission to the ICU. We used selbal, a machine learning method, to identify the balance of microbial taxa most closely associated with 28-day mortality.

RESULTS

We found that a proportional ratio of four taxa could be used to distinguish patients with a higher risk of mortality from patients with a lower risk of mortality (p = .02). We named this binarized ratio our microbiome mortality index (MMI). Patients with a high MMI had a higher 28-day mortality compared to those with a low MMI (hazard ratio, 2.2, 95% confidence interval 1.1-4.3), and remained significant after adjustment for other ICU mortality predictors, including the presence of the acute respiratory distress syndrome (ARDS) and the Acute Physiology and Chronic Health Evaluation (APACHE II) score (hazard ratio, 2.5, 95% confidence interval 1.4-4.7). High mortality was driven by taxa from the Anaerococcus (genus) and Enterobacteriaceae (family), while lower mortality was driven by Parasutterella and Campylobacter (genera).

CONCLUSIONS

Dysbiosis in the gut of critically ill patients is an independent risk factor for increased mortality at 28 days after adjustment for clinically significant confounders. Gut dysbiosis may represent a potential therapeutic target for future ICU interventions.

Causal associations between gut microbiota and sepsis: A two-sample Mendelian randomization study

BACKGROUND

Targeting the gut microbiota may become a new therapeutic to prevent and treat sepsis. Nonetheless, the causal relationship between specific intestinal flora and sepsis is still unclear.

METHODS

A two-sample Mendelian randomization study was performed using the summary statistics of gut microbiota from the largest available genome-wide association study (n = 18,340). The summary statistics of sepsis were obtained from the UK Biobank (n = 486,484). Inverse-variance weighted, weighted median and MR-Egger were used to examine the causal association between gut microbiota and sepsis. Cochrane's Q test, MR-Egger intercept test, MR-PRESSO Global test and Rucker's Q'-test were used for sensitivity analyses. The leave-one method was used for testing the stability of MR results, and Bonferroni-corrected was used to test the strength of the causal relationship between exposure and outcome.

RESULTS

Nine intestinal microflora were found causally associated with sepsis, and 11 intestinal microflora were causally associated with 28-day death in sepsis. Among them, Order Victivallales had a strong causality with lower risk of sepsis (OR = 0.86, 95% CI: 0.78-0.94, p = .00165) and lower 28-day mortality of sepsis (OR = 0.68, 95% CI: 0.53-0.87, p = .00179) after Bonferroni-corrected test. No pleiotropy was detected.

CONCLUSIONS

Through the two-sample MR analysis, we identified the specific intestinal flora that had a causal relationship with the risk and prognosis of sepsis at the level of gene prediction, which may provide helpful biomarkers for early disease diagnosis and potential therapeutic targets for sepsis.

Relationship between gut microbiota dysbiosis and immune indicator in children with sepsis

Sepsis is a life-threatening multiple-organ injury caused by disordered host immune response to microbial infection. However, the correlation between gut microbiota dysbiosis and immune indicators remains unexplored. To address this gap in knowledge, we carried out 16 S rDNA sequencing, analyzed clinical fecal samples from children with sepsis (n = 30) and control children (n = 25), and obtained immune indicators, including T cell subtypes (CD3+, CD3+CD4+, CD3+CD8+, and CD4/CD8), NK cells, cytokines (IL-2, IL-4, IL-6, IL-10, TNF-α and IFN-γ), and immunoglobulin indices (IgA, IgE, IgM and IgG). In addition, we analyzed the correlation between gut microbiota dysbiosis and immune indicators, and evaluated the clinical discriminatory power of discovered bacterial biomarkers. We found that children with sepsis exhibited gut bacterial dysbiosis and low alpha diversity. The Spearman's rank correlation coefficient suggested that Rhodococcus erythropolis had a significantly positive correlation with IFN-γ and CD3+ T cells. Klebsiella pneumoniae and Streptococcus mitis were significantly correlated with NK cells. Bacteroides uniformis was significantly positively correlated with IgM and erythrocyte sedimentation rate, and Eubacterium eligens was significantly positively correlated with IL-4 and CD3+CD8+ T cells. The biomarkers discovered in this study had strong discriminatory power. These changes in the gut microbiome may be closely related to immunologic dysfunction and to the development or exacerbation of sepsis. However, a large sample size is required for verification.

Analysis of the dynamic changes in gut microbiota in patients with different severity in sepsis

BACKGROUND

The gastrointestinal tract contains a massive microbiota, and targeting the gut could be a potential intervention for sepsis. However, the interaction between sepsis and the intestinal microbiota is defined as an "incompletely understood bidirectional relationship".

METHODS

This retrospective observational cohort study investigated the fecal microbiota of sepsis patients admitted to the Department of Critical Care Medicine of the Central Hospital of Wuhan, China, from May 2019 to January 2020. 14 septic patients were divided into the non-severe group and the severe group according to the Acute Physiology and Chronic Health Evaluation II (APACHE II) score. Herein, fecal samples were serially collected on admission, the third, fourth, and fifth days, and ICU discharge. The fecal microbiota was analyzed by 16S rRNA gene sequencing and its correlation with clinical parameters was evaluated.

RESULTS

Bacteroidetes, Firmicutes, and Proteobacteria were dominant phyla at ICU admission, and fecal biodiversity was not significantly different between the non-severe group (APACHE II < 15) and the severe group (APACHE II > 15). However, the diversity of the gut microbiota was significantly lower at ICU discharge than that at ICU admission with the extension of treatment time. Further significant difference flora analysis (LEfSe) showed that the genera Veillonella and Ruminococcus were the most discriminant biomarkers at ICU admission in non-severe and severe patients, respectively, while Enterococcus was the most discriminant biomarker at ICU discharge in all septic patients. Of note, liver function tests, including ALT, AST, TBIL, and DBIL correlated with the prevalence of various bacterial genera.

CONCLUSIONS

The diversity of the gut microbiota in patients with sepsis decreases dramatically during ICU stay, and there are distinct dynamic changes in gut microbiota among patients with different severity in sepsis.

Association of obesity and mortality in sepsis patients: A meta-analysis from observational evidence

The project aims to investigate the correlation between obesity, overweight, or low body weight and the risk of mortality in sepsis patients. We performed a rigorous and thorough search of major electronic databases, including PubMed, Web of Science, EMBASE, and Cochrane Library, from the inception of these databases up to March 28, 2023. The data were analyzed with Stata software (version 16.0). Twelve studies incorporating 521,207 individuals were enrolled. The results demonstrated that obesity (OR = 0.82; 95% CI: 0.69-0.97; P < 0.001) or overweight (OR = 0.83; 95% CI: 0.73-0.94; P < 0.001) decreased the risk of mortality in sepsis patients. Instead, the reverse phenomena existed in patients with a low weight (OR = 1.43; 95%CI: 1.16-1.76; P = 0.038). There is an "obesity paradox" phenomenon in the mortality of obese and overweight patients with sepsis, but low body weight is an independent risk factor for the mortality of sepsis patients. This study demonstrated that the mortality in sepsis patients and obesity or overweight were negatively correlated, but displayed a significant positive relation to low weight.

Calcium-Sensitive Receptors Alters Intestinal Microbiota Metabolites Especially SCFAs and Ameliorates Intestinal Barrier Damage in Neonatal Rat Endotoxemia

Purpose

The calcium-sensing receptor (CaSR) acts as a major modulator of tissue responses related to calcium homeostasis and expresses highly in the mammalian intestine. Endotoxemia tends to impair intestinal barrier function and poses significant obstacles in clinical treatment. This work is designed to decipher whether CaSR can protect lipopolysaccharide (LPS)-induced intestinal barrier dysfunction in neonatal rats by targeting intestinal metabolites.

Patient and Methods

In this study, we utilized gas chromatography (GC) combined with liquid chromatography-mass spectrometry (LC-MS) to quantitatively analyze SCFAs and metabolites in fecal samples of 24 neonatal rats with LPS induced endotoxemia.

Results

Our results showed that CaSR alleviated endotoxin damage to the intestinal tight junction structure and upregulated the levels of butyric acid, propionic acid, valeric acid, and isovaleric acid in short-chain fatty acids (SCFAs). Non-targeted metabolomics analysis indicated that CaSR improved intestinal metabolic disorders by regulating glycerophospholipid metabolism, α-linolenic acid metabolism, as well as sphingolipids metabolism.

Conclusion

CaSR can alter intestinal microbiota metabolites, especially SCFAs, and improve intestinal barrier damage in neonatal rat endotoxemia.

Postbiotics as potential new therapeutic agents for sepsis

Sepsis is the main cause of death in critically ill patients and gut microbiota dysbiosis plays a crucial role in sepsis. On the one hand, sepsis leads to the destruction of gut microbiota and induces and aggravates terminal organ dysfunction. On the other hand, the activation of pathogenic gut flora and the reduction in beneficial microbial products increase the susceptibility of the host to sepsis. Although probiotics or fecal microbiota transplantation preserve gut barrier function on multiple levels, their efficacy in sepsis with intestinal microbiota disruptions remains uncertain. Postbiotics consist of inactivated microbial cells or cell components. They possess antimicrobial, immunomodulatory, antioxidant and antiproliferative activities. Microbiota-targeted therapy strategies, such as postbiotics, may reduce the incidence of sepsis and improve the prognosis of patients with sepsis by regulating gut microbial metabolites, improving intestinal barrier integrity and changing the composition of the gut microbiota. They offer a variety of mechanisms and might even be superior to more conventional 'biotics' such as probiotics and prebiotics. In this review, we present an overview of the concept of postbiotics and summarize what is currently known about postbiotics and their prospective utility in sepsis therapy. Overall, postbiotics show promise as a viable adjunctive therapy option for sepsis.

Causal effects of gut microbiota on sepsis: a two-sample Mendelian randomization study

BACKGROUND

Recent studies had provided evidence that the gut microbiota is associated with sepsis. However, the potential causal relationship remained unclear.

METHODS

The present study aimed to explore the causal effects between gut microbiota and sepsis by performing Mendelian randomization (MR) analysis utilizing publicly accessible genome-wide association study (GWAS) summary-level data. Gut microbiota GWAS (N = 18,340) were obtained from the MiBioGen study and GWAS-summary-level data for sepsis were gained from the UK Biobank (sepsis, 10,154 cases; 452,764 controls). Two strategies were used to select genetic variants, i.e., single nucleotide polymorphisms (SNPs) below the locus-wide significance level (1 × 10-5) and the genome-wide statistical significance threshold (5 × 10-8) were chosen as instrumental variables (IVs). The inverse variance weighted (IVW) was used as the primary method for MR study, supplemented by a series of other methods. Additionally, a set of sensitivity analysis methods, including the MR-Egger intercept test, Mendelian randomized polymorphism residual and outlier (MR-PRESSO) test, Cochran's Q test, and leave-one-out test, were carried out to assess the robustness of our findings.

RESULTS

Our study suggested that increased abundance of Deltaproteobacteria, Desulfovibrionales, Catenibacterium, and Hungatella were negatively associated with sepsis risk, while Clostridiaceae1, Alloprevotella, LachnospiraceaeND3007group, and Terrisporobacter were positively correlated with the risk of sepsis. Sensitivity analysis revealed no evidence of heterogeneity and pleiotropy.

CONCLUSION

This study firstly found suggestive evidence of beneficial or detrimental causal associations of gut microbiota on sepsis risk by applying MR approach, which may provide valuable insights into the pathogenesis of microbiota-mediated sepsis and strategies for sepsis prevention and treatment.

GLOBAL SIGNATURES OF THE MICROBIOME AND METABOLOME DURING HOSPITALIZATION OF SEPTIC PATIENTS

ABSTRACT

Background: The gut plays an important role in the development of sepsis and acts as one of the possible drivers of multiple-organ dysfunction syndrome. This study aimed to explore the dynamic alterations in the gut microbiota and its metabolites in septic patients at different stages of intensive care unit (ICU) admission. Methods: In this prospective observational study, a total of 109 fecal samples from 23 septic patients, 16 nonseptic ICU patients and 10 healthy controls were analyzed. 16S rRNA gene sequencing and ultra-performance liquid chromatography coupled to tandem mass spectrometry targeted metabolomics were used for microbiota and metabolome analysis. A prediction model combining the Sequential Organ Failure Assessment score, Klebsiella , taurocholic acid, and butyric acid was used to predict the prognosis of sepsis. Results: The diversity and dominant species of the gut microbiota of septic patients were significantly disturbed. The proportions of normal gut microbiota, such as Firmicutes on the phylum level, as well as Faecalibacterium, Subdoligranulum , Ruminococcus , Agathobacter , and Blautia on the genus level, were decreased at different stages of ICU admission, while the proportions of potential pathogenic bacteria, such as Proteobacteria on the phylum level, and Enterococcus and Stenotrophomonas on the genus level were significantly increased. In addition, the amount of short-chain fatty acids and secondary bile acids decreased in septic patients, while that of the primary bile acids increased markedly. Bacterial richness and diversity were lower in the nonsurviving patients than those in the surviving patients in the later stage of ICU admission. In the nomogram model, the higher abundance of Klebsiella , concentration of taurocholic acid, and Sequential Organ Failure Assessment score, combined with a lower butyric acid concentration, could predict a higher probability of death from sepsis. Conclusions: Our study indicated that the dynamical alterations of gut microbiota and its metabolites were associated with the prognosis of the sepsis. Based on these alterations and clinical indicators, a nomogram model to predict the prognosis of septic patients was performed.

Dysbiosis of a microbiota-immune metasystem in critical illness is associated with nosocomial infections

Critically ill patients in intensive care units experience profound alterations of their gut microbiota that have been linked to a high risk of hospital-acquired (nosocomial) infections and adverse outcomes through unclear mechanisms. Abundant mouse and limited human data suggest that the gut microbiota can contribute to maintenance of systemic immune homeostasis, and that intestinal dysbiosis may lead to defects in immune defense against infections. Here we use integrated systems-level analyses of fecal microbiota dynamics in rectal swabs and single-cell profiling of systemic immune and inflammatory responses in a prospective longitudinal cohort study of critically ill patients to show that the gut microbiota and systemic immunity function as an integrated metasystem, where intestinal dysbiosis is coupled to impaired host defense and increased frequency of nosocomial infections. Longitudinal microbiota analysis by 16s rRNA gene sequencing of rectal swabs and single-cell profiling of blood using mass cytometry revealed that microbiota and immune dynamics during acute critical illness were highly interconnected and dominated by Enterobacteriaceae enrichment, dysregulated myeloid cell responses and amplified systemic inflammation, with a lesser impact on adaptive mechanisms of host defense. Intestinal Enterobacteriaceae enrichment was coupled with impaired innate antimicrobial effector responses, including hypofunctional and immature neutrophils and was associated with an increased risk of infections by various bacterial and fungal pathogens. Collectively, our findings suggest that dysbiosis of an interconnected metasystem between the gut microbiota and systemic immune response may drive impaired host defense and susceptibility to nosocomial infections in critical illness.

Leveraging the microbiome in the treatment of sepsis: potential pitfalls and new perspectives

PURPOSE OF REVIEW

This review aims to provide an overview of the current knowledge about microbiota-targeted therapies in sepsis, and calls out - despite recent negative studies - not to halt our efforts of translating these tools into regular medical practice.

RECENT FINDINGS

The intestinal microbiome has an important role in shaping our immune system, and microbiota-derived metabolites prime innate and adaptive inflammatory responses to infectious pathogens. Microbiota composition is severely disrupted during sepsis, which has been linked to increased risk of mortality and secondary infections. However, efforts of using these microbes as a tool for prognostic or therapeutic purposes have been unsuccessful so far, and recent trials studying the impact of probiotics in critical illness did not improve patient outcomes. Despite these negative results, researchers must continue their attempts of harnessing the microbiome to improve sepsis survival in patients with a high risk of clinical deterioration. Promising research avenues that could potentially benefit sepsis patients include the development of next-generation probiotics, use of the microbiome as a theranostic tool to direct therapy, and addressing the restoration of microbial communities following ICU discharge.

SUMMARY

Although research focused on microbiome-mediated therapy in critically ill patients has not yielded the results that were anticipated, we should not abandon our efforts to translate promising preclinical findings into clinical practice.

Impact of Intensive Care Unit Nutrition on the Microbiome and Patient Outcomes

The bipartite relationship between nutrition and the intestinal microbiome represents an exciting frontier in critical care medicine. In this review, the authors first address these topics independently, leading with a summary of recent clinical studies assessing intensive care unit nutritional strategies, followed by an exploration of the microbiome in the context of perioperative and intensive care, including recent clinical data implicating microbial dysbiosis as a key driver of clinical outcomes. Finally, the authors address the intersection of nutrition and the microbiome, exploring the use of supplemental pre-, pro-, and synbiotics to influence microbial composition and improve outcomes in critically ill and postsurgical patients.

[Bacterial gut microbiota-key player in sepsis]

The gut microbiota is comprised of over 1200 different bacteria and forms a symbiotic community with the human organism, the holobiont. It plays an important role in the maintenance of homeostasis, e.g., of the immune system and essential metabolic processes. Disturbances in the balance of this reciprocal relationship are called dysbiosis and, in the field of sepsis, are associated with incidence of disease, extent of the systemic inflammatory response, severity of organ dysfunction, and mortality. In addition to providing guiding principles in the fascinating relationship between "human and microbe," this article summarizes recent findings regarding the role of the bacterial gut microbiota in sepsis, which is one a very relevant in intensive care medicine.

Identification and Analysis of Gut Microbiota and Functional Metabolism in Decompensated Cirrhosis with Infection

BACKGROUND AND AIMS

Intestinal dysbiosis play a role in the adverse outcomes of sepsis and septic shock. However, variations in bacterial diversity and microbiota-related functional metabolic alterations within the gut microbiome in decompensated cirrhosis (DC) patients with infection remain unknown.

METHODS

We conducted 16-srRNA sequencing on stool samples (n=51: sepsis, 27/no sepsis, 24) collected from consecutive DC patients upon admission. Bacterial diversity, significant taxa, and respective metabolic profiling were performed based on subgroup comparisons. Conet/Cytoscape was utilized to identify significant non-random patterns of bacterial copresence and mutual exclusion for clinical events.

RESULTS

Genera associated with pathogenicity in conditions of immune exhaustion (Corynebacterium, Lautropia) were predominant in patients with sepsis. Metabolic pathways associated with oxidative stress and endotoxemia [lipopolysaccharide (LPS) synthesis and sulfur relay] were significantly upregulated in sepsis. Specific taxa were associated with sites of infection in DC patients. Protective oxidant pathways that increase glutathione were upregulated in those without sepsis. Gammaproteobacteria family of sulfur-metabolizing bacteria, exaggeration of orally predominant pathogens (Prevotella), and pathways of severe LPS-related hyperinflammatory stress were notable in those with interleukin-6 levels >1,000 pg/dL. Pathogenic genera related to an immune deficient state was significant in DC with ≥2 infection episodes. Megamonas was associated with survival during the same admission.

CONCLUSIONS

Specific gut microbiota and their metabolites were associated with sepsis and related events in patients with DC. Identifying beneficial strains that reduce immune exhaustion and supplementation of favorable metabolites could improve therapeutics for DC and sepsis, for which larger prospective, well controlled population-based studies remain an unmet need.

Contributions of the microbiota to the systemic inflammatory response

The health of the intestinal microbiota impacts tolerance at homeostasis and the strength of the inflammation response during acute bloodstream infections. A complete understanding of the feedback loop between systemic inflammation and dysregulation of the gut microbiota is necessary for inflammation management. Here we will review the many ways in which the microbiota can influence the systemic pro-inflammatory response. Short-chain fatty acids, produced through the microbial metabolism of dietary fibers, can suppress inflammation systemically; in the absence of a balanced diet or disruption of the microbiota through antibiotics, there is disrupted metabolite production, leading to systemic inflammation. Dysbiosis or inflammation in the intestines can lead to a breakdown of the sturdy intestinal-epithelial barrier. When this barrier is perturbed, immunogenic lipopolysaccharides or extracellular vesicles enter the bloodstream and induce excessive inflammation. Necessary clinical treatments, such as antifungals or antibacterials, induce microbiota dysregulation and thus increased risk of endotoxemia; though probiotics may aid in improving the microbiota health and have been shown to deflate inflammation during sepsis. Within this complicated relationship: What is in control, the dysbiotic microbiota or the systemic inflammation?

Immunopathophysiology of human sepsis

Sepsis is an ill-defined syndrome yet is a leading cause of morbidity and mortality worldwide. The most recent consensus defines sepsis as life-threatening organ dysfunction caused by a dysregulated host response to infection. However, this definition belies the complexity and breadth of immune mechanisms involved in sepsis, which are characterized by simultaneous hyperinflammation and immune suppression. In this review, we describe the immunopathogenesis of sepsis and highlight some recent pathophysiological findings that have expanded our understanding of sepsis. Sepsis endotypes can be used to divide sepsis patients in different groups with distinct immune profiles and outcomes. We also summarize evidence on the role of the gut microbiome in sepsis immunity. The challenge of the coming years will be to translate our increasing knowledge about the molecular mechanisms underlying sepsis into therapies that improve relevant patient outcomes.

Rate and predictors of 30-day readmission for clostridiodes difficile: a United States analysis

BACKGROUND

Clostridiodes difficile is a leading cause of healthcare-associated diarrhea. In this study, we aimed to identify the rates and predictors for 30-day readmissions of Clostridiodes difficile Enterocolitis (CDE) in the United States.

METHODS

We conducted a retrospective study of the Nationwide Readmissions Database to identify adult hospitalizations with a principal diagnosis of CDE for 2018. Individuals <18 years old and elective hospitalizations were excluded. Primary outcomes included readmission rate and the top ten principal diagnosis on readmission, while the secondary outcomes were inpatient mortality, hospital costs and independent predictors of 30-day all-cause readmissions. Furthermore, we devised a scoring system to estimate the risk of CDE readmissions. Stata® Version 16 was used for statistical analysis and p-values ≤0.05 were statistically significant.

RESULTS

We identified 94,668 index hospitalizations and 18,296 readmissions at 30-days for CDE in 2018. The 30-day all-cause readmission rate was 25.7%. On readmission, CDE was the most common principal diagnosis (25.7%), followed by unspecified sepsis, and acute renal failure. A female predominance was also noted for index and 30-day readmissions of CDE. Compared to index admissions, we noted higher odds of inpatient mortality [4.4 vs 1.4%, Odds Ratio (OR):3.32, 95% Confidence Interval (CI):2.87-3.84, p < 0.001], longer mean length of stay (LOS) [6.4 vs 5.6 days, Mean Difference (MD):0.9, 95% CI:0.7-1.0, p < 0.001), and higher mean total hospital charge (THC) [$56,015 vs $40,871, MD:15,144, 95% CI:13,260-17,027, p < 0.001] for 30-day readmissions of CDE. Independent predictors for 30-day all-cause readmissions of CDE included discharged against medical advice (AMA) [Adjusd Hazard Ratio (aHR):2.01, 95% CI:1.73-2.53, p < 0.001], diabetes mellitus (DM) [aHR:1.22, 95% CI:1.16-1.29, p < 0.001], and chronic kidney disease (CKD) [aHR:1.29, 95% CI:1.21-1.37, p < 0.001].

CONCLUSION

The all-cause 30-day readmission rate and inpatient mortality for CDE was 25.7% and 4.4%, respectively. Discharge AMA, DM and CKD were independent predictors for 30-day all-cause readmissions of CDE.KEY MESSAGEThe 30-day all-cause readmission rate for Clostridiodes difficile Enterocolitis was noted to be 21.4% in 2018.Independent predictors of 30-day all-cause readmissions for Clostridiodes difficile Enterocolitis include diabetes mellitus, discharged against medical advice and chronic kidney disease.Readmissions of Clostridiodes difficile Enterocolitis had higher mortality rates, healthcare cost and length of hospital stay compared to index admissions.

Quantifying the breadth of antibiotic exposure in sepsis and suspected infection using spectrum scores

A retrospective cohort study. Studies to quantify the breadth of antibiotic exposure across populations remain limited. Therefore, we applied a validated method to describe the breadth of antimicrobial coverage in a multicenter cohort of patients with suspected infection and sepsis. We conducted a retrospective cohort study across 21 hospitals within an integrated healthcare delivery system of patients admitted to the hospital through the ED with suspected infection or sepsis and receiving antibiotics during hospitalization from January 1, 2012, to December 31, 2017. We quantified the breadth of antimicrobial coverage using the Spectrum Score, a numerical score from 0 to 64, in patients with suspected infection and sepsis using electronic health record data. Of 364,506 hospital admissions through the emergency department, we identified 159,004 (43.6%) with suspected infection and 205,502 (56.4%) with sepsis. Inpatient mortality was higher among those with sepsis compared to those with suspected infection (8.4% vs 1.2%; P < .001). Patients with sepsis had higher median global Spectrum Scores (43.8 [interquartile range IQR 32.0-49.5] vs 43.5 [IQR 26.8-47.2]; P < .001) and additive Spectrum Scores (114.0 [IQR 57.0-204.5] vs 87.5 [IQR 45.0-144.8]; P < .001) compared to those with suspected infection. Increased Spectrum Scores were associated with inpatient mortality, even after covariate adjustments (adjusted odds ratio per 10-point increase in Spectrum Score 1.31; 95%CI 1.29-1.33). Spectrum Scores quantify the variability in antibiotic breadth among individual patients, between suspected infection and sepsis populations, over the course of hospitalization, and across infection sources. They may play a key role in quantifying the variation in antibiotic prescribing in patients with suspected infection and sepsis.

Traditional Chinese Medicine: A promising strategy to regulate inflammation, intestinal disorders and impaired immune function due to sepsis

Sepsis is described as a dysregulation of the immune response to infection, which leads to life-threatening organ dysfunction. The interaction between intestinal microbiota and sepsis can't be ignored. Furthermore, the intestinal microbiota may regulate the progress of sepsis and attenuate organ damage. Thus, maintaining or restoring microbiota may be a new way to treat sepsis. Traditional Chinese medicine (TCM) assumes a significant part in the treatment of sepsis through multi-component, multi-pathway, and multi-targeting abilities. Moreover, TCM can prevent the progress of sepsis and improve the prognosis of patients with sepsis by improving the imbalance of intestinal microbiota, improving immunity and reducing the damage to the intestinal barrier. This paper expounds the interaction between intestinal microbiota and sepsis, then reviews the current research on the treatment of sepsis with TCM, to provide a theoretical basis for its clinical application.

Clinical Approach to Nosocomial Bacterial Sepsis

Bacterial sepsis and septic shock are associated with a high mortality, and when clinically suspected, clinicians must initiate broad-spectrum antimicrobials within the first hour of diagnosis. Thorough review of prior cultures involving multidrug-resistant (MDR) pathogens along with other likely pathogens should be performed to provide an appropriate broad-spectrum empiric antibiotic coverage. The appropriate antibiotic loading dose followed by individualized modification of maintenance dose should be implemented based on the presence of hepatic or renal dysfunction. Use of procalcitonin is no longer recommended to determine need for initial antibacterial therapy and for de-escalation. Daily reevaluation of appropriateness of treatment is necessary based on the culture results and clinical response. All positive cultures should be carefully screened for possible contamination or colonization, which may not represent the true organism causing the sepsis. Culture negative sepsis accounts for one-half of all cases, and de-escalation of initial antibiotic regimen should be done gradually in these patients with close monitoring.

Rectal microbiota are coupled with altered cytokine production capacity following community-acquired pneumonia hospitalization

Human studies describing the immunomodulatory role of the intestinal microbiota in systemic infections are lacking. Here, we sought to relate microbiota profiles from 115 patients with community-acquired pneumonia (CAP), both on hospital admission and following discharge, to concurrent circulating monocyte and neutrophil function. Rectal microbiota composition did not explain variation in cytokine responses in acute CAP (median 0%, IQR 0.0%–1.9%), but did one month following hospitalization (median 4.1%, IQR 0.0%–6.6%, p = 0.0035). Gene expression analysis of monocytes showed that undisrupted microbiota profiles following hospitalization were associated with upregulated interferon, interleukin-10, and G-protein-coupled-receptor-ligand-binding pathways. While CAP is characterized by profoundly distorted gut microbiota, the effects of these disruptions on cytokine responses and transcriptional profiles during acute infection were absent or modest. However, rectal microbiota were related to altered cytokine responses one month following CAP hospitalization, which may provide insights into potential mechanisms contributing to the high risk of recurrent infections following hospitalization.

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Rectal microbiota are disrupted at hospitalization for CAP and one month thereafter

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No variation in cytokines is explained by gut microbiota in the acute phase of CAP

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Following recovery, gut microbiota are linked with variation in cytokine responses

Health care consequences of hospitalization with Clostrioides difficile infection: a propensity score matching study

Background

Clostridiodies difficile infection (CDI) has been characterized by the Center for Disease Control and Prevention (CDC) as an urgent public health threat and a major concern in hospital, outpatient and extended-care facilities worldwide.

Methods

A retrospective cohort study of patients aged ≥ 18 hospitalized with CDI in New York State (NYS) between January 1, 2014–December 31, 2016. Data were extracted from NY Statewide Planning and Research Cooperative (SPARCS) and propensity score matching was performed to achieve comparability of the CDI (exposure) and non-CDI (non-exposure) groups. Of the 3,714,486 hospitalizations, 28,874 incidence CDI cases were successfully matched to 28,874 non-exposures.

Results

The matched pairs comparison demonstrated that CDI cases were more likely to be readmitted to the hospital at 30 (28.26% vs. 19.46%), 60 (37.65% vs. 26.02%), 90 (42.93% vs. 30.43) and 120 days (46.47% vs. 33.74), had greater mortality rates at 7 (3.68% vs. 2.0%) and 180 days (20.54% vs. 11.96%), with significant increases in length of stay and total hospital charges (p < .001, respectively).

Conclusions

CDI is associated with a large burden on patients and health care systems, significantly increasing hospital utilization, costs and mortality.

Sufentanil Alleviates Sepsis-Induced Myocardial Injury and Stress Response in Rats through the ERK/GSK-3β Signaling Axis

Objective

To explore the effect and possible mechanism of sufentanil on sepsis-induced myocardial injury and stress response in rats.

Methods

The cecal ligation and puncture (CLP) method was utilized to establish the sepsis model of rats to explore the effect of sufentanil pretreatment with different concentrations on myocardial injury and oxidative stress in CLP rats. Echocardiogram was applied for detecting cardiac hemodynamic parameters in rats; hematoxylin and eosin (HE) staining as well as TUNEL staining was done for observing pathological changes of myocardial tissue and cardiomyocyte apoptosis in rats, respectively; biochemical testing and enzyme-linked immunosorbent assay (ELISA) were done for determining myocardial injury marker level in serum, oxidative stress substances in myocardial tissue, and neuroendocrine hormone level in serum of rats, respectively; finally, Western blot was performed for checking the expression level of ERK/GSK-3β signaling pathway-related proteins in myocardial tissue of rats.

Results

A model of rat with sepsis-induced myocardial injury was constructed with the CLP method. Specifically, this rat model was characterized by obvious cardiac function and tissue damage, cardiomyocyte apoptosis, and oxidative stress response. Sufentanil pretreatment significantly improved cardiac function injury, alleviated pathological injury and oxidative stress response in myocardial tissue, and inhibited cardiomyocyte apoptosis. Specifically, after sufentanil pretreatment, left ventricular end-diastolic dimension (LVEDD) and left ventricular end-systolic dimension (LVESD) were downregulated, and left ventricular ejection fraction (LVEF) was upregulated; the level of B-type natriuretic peptide (BNP) of serum, creatine kinase isoenzyme (CK-MB), and troponin (cTnl) decreased; besides, malondialdehyde (MDA) level was declined, while activities of superoxide dismutase (SOD) and catalase (CAT) were increased. What is more, further mechanism exploration also revealed that sufentanil could reverse the activity of the sepsis-induced ERK/GSK-3β signaling pathway.

Conclusion

Sufentanil has an obvious protective effect on myocardial injury and stress response in CLP rats, and this protective effect may be related to the activation of the ERK/GSK-3β signaling pathway.

Effect of antimicrobial administration on fecal microbiota of critically ill dogs: dynamics of antimicrobial resistance over time

Background

Multidrug resistance in companion animals poses significant risks to animal and human health. Prolonged antimicrobial drug (AMD) treatment in animals is a potential source of selection pressure for antimicrobial resistance (AMR) including in the gastrointestinal microbiota. We performed a prospective study of dogs treated for septic peritonitis, pyometra, or bacterial pneumonia and collected repeated fecal samples over 60 days. Bacterial cultures and direct molecular analyses of fecal samples were performed including targeted resistance gene profiling.

Results

Resistant Escherichia coli increased after 1 week of treatment (D1:21.4% vs. D7:67.9% P < 0.001) and returned to baseline proportions by D60 (D7:67.9% vs D60:42.9%, P = 0.04). Dogs with septic peritonitis were hospitalized significantly longer than those with pneumonia or pyometra. Based on genetic analysis, Simpson’s diversity index significantly decreased after 1 week of treatment (D1 to D7, P = 0.008), followed by a gradual increase to day 60 (D1 and D60, P = 0.4). Detection of CTX-M was associated with phenotypic resistance to third-generation cephalosporins in E. coli (OR 12.1, 3.3–68.0, P < 0.001). Lincosamide and macrolide-resistance genes were more frequently recovered on days 14 and 28 compared to day 1 (P = 0.002 and P = 0.004 respectively).

Conclusion

AMR was associated with prescribed drugs but also developed against AMDs not administered during the study. Companion animals may be reservoirs of zoonotic multidrug resistant pathogens, suggesting that veterinary AMD stewardship and surveillance efforts should be prioritized.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s42523-022-00178-9.

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

Objectives

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

Method

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

Results

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

Conclusion

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