Severe sepsis and septic shock. Definitions, epidemiology, and clinical manifestations

A Guide to the Use of Vasopressors and Inotropes for Patients in Shock

Shock is a life-threatening circulatory failure that results in inadequate tissue perfusion and oxygenation. Vasopressors and inotropes are vasoactive medications that are vital in increasing systemic vascular resistance and cardiac contractility, respectively, in patients presenting with shock. To be well versed in using these agents is an important skill to have in the critical care setting where patients can frequently exhibit symptoms of shock. In this review, we will discuss the pathophysiological mechanisms of shock and evaluate the current evidence behind the management of shock with an emphasis on vasopressors and inotropes.

A New Strategy for Targeting UCP2 to Modulate Glycolytic Reprogramming as a Treatment for Sepsis A New Strategy for Targeting UCP2

Sepsis is a severe and life-threatening disease caused by infection, characterized by a dysregulated immune response. Unfortunately, effective treatment strategies for sepsis are still lacking. The intricate interplay between metabolism and the immune system limits the treatment options for sepsis. During sepsis, there is a profound shift in cellular energy metabolism, which triggers a metabolic reprogramming of immune cells. This metabolic alteration impairs immune responses, giving rise to excessive inflammation and immune suppression. Recent research has demonstrated that UCP2 not only serves as a critical target in sepsis but also functions as a key metabolic switch involved in immune cell-mediated inflammatory responses. However, the regulatory mechanisms underlying this modulation are complex. This article focuses on UCP2 as a target and discusses metabolic reprogramming during sepsis and the complex regulatory mechanisms between different stages of inflammation. Our research indicates that overexpression of UCP2 reduces the Warburg effect, restores mitochondrial function, and improves the prognosis of sepsis. This discovery aims to provide a promising approach to address the significant challenges associated with metabolic dysfunction and immune paralysis.

The Predictive Value of Systemic Immune-Inflammation Index and Symptom Severity Score for Sepsis and Systemic Inflammatory Response Syndrome in Odontogenic Infections

Acute Odontogenic Infections (OI) are the leading cause of emergency visits and hospitalizations to the maxillofacial department, and may induce systemic inflammatory complications. Increasing numbers of OI patients need extended hospitalizations, various treatments, and intensive care. The Symptom Severity score (SS) helps doctors assess the likelihood of infection and admission complications. Systemic Immune-inflammation Index (SII) is a biomarker-based inflammatory prognosis score. It was hypothesized that greater SII and SS values might suggest a higher risk for sepsis and systemic inflammatory response syndrome (SIRS). Therefore, this research aims to discover whether SII and SS scores can reliably predict odontogenic infection severity and prognosis, and if they can be used to predict the development of SIRS and sepsis in OI using admission features. The study was designed as a retrospective cohort, with patients' data being retrieved from medical records between January 2017 to April 2022. A total of 108 OI patients were matched 1:1 as low-severity and high-severity groups. Most individuals with severe infections had diabetes and smoking as comorbidities. Severe patients had longer hospital stays (12.0 days vs. 4.1 days), although mortality rates did not significantly differ. A total of 11.1% lower-severity patients (Group A) had SIRS during hospitalization, compared to Group B with 25.9%. Group A had 7.4% of patients that developed sepsis compared to Group B's rate of 22.2%. The correlation between OI's SS and SII index values was positive and statistically significant (r = 0.6314). The total SII index mean was 1303, whereas the mean values by severity were 696.3 in Group A and 2312.4 in Group B. Group A's mean SS score was 6.1, while Group B's was 13.6. According to the calculated AUC plots, SII and SS scores were accurate predictors of sepsis and SIRS development using OI admission parameters. The adjusted odds ratio for SIRS in OI patients was 2.09, and 2.27 for sepsis. Medical professionals and dentistry teams should be encouraged to use the SII and SS scores to diagnose and anticipate sepsis and SIRS, hence improving disease management decisions.

Heparin-Binding Protein Aggravates Acute Lung Injury in Septic Rats by Promoting Macrophage M1 Polarization and NF-κB Signaling Pathway Activation

Objective

Heparin-binding protein (HBP) plays an important role in sepsis and is a prognostic biomarker in patients with sepsis, but the role of HBP in the pathogenesis of sepsis-associated acute lung injury (ALI) remains unclear. This study aimed to investigate the role of HBP in sepsis-induced ALI and its underlying molecular mechanisms.

Methods

The cecal ligation and puncture (CLP) model was used to induce ALI in mice and randomly divided into 4 groups: control group, CLP (rats treated with cecal ligation and puncture), HBP (rats treated with CLP and HBP injection), and HBP + UFH (rats treated with CLP and injection of HBP and unfractionated heparin). Subsequently, HBP expression in rat serum and lung tissues was detected by qRT-PCR, edema and pathological changes in lung tissue by lung wet-to-dry weight ratio (W/D) and HE staining, myeloperoxidase (MPO) and superoxide dismutase (SOD) activities in lung tissues by detection kits. Additionally, ELISA and western blot were applied for the determination of IL-6, TNF-α, and IL-1β expression in rat bronchoalveolar lavage fluid, and iNOS, Arg-1, Mrc1, NF-κBp65, IKKα, IκBα, and p-IκBα expression in lung tissues.

Results

The expression levels of HBP in serum and lung tissues of rats in the HBP group were significantly increased, the lung tissues were severely injured, accompanied by a significant increase in MPO activity but a significant decrease in SOD activity, and the levels of IL-6, TNF-α, and IL-1β in bronchoalveolar lavage fluid were significantly increased. In addition, the expression levels of iNOS, NF-κB p65, IKKα, and p-IκBα in the lung tissues of rats in the HBP group were significantly increased, while the addition of unfractionated heparin reversed the above results.

Conclusion

HBP aggravates ALI in septic rats, and its mechanism may be related to the promotion of macrophage M1 polarization and activation of the NF-κB signaling pathway.

Performance of microvesicles as biomarkers of clinical outcome in sepsis and trauma: A pilot study

Sepsis remains one of the main causes of death in intensive care unit (ICU) worldwide, despite all technological and scientific advances. Microvesicles (MV) have become promising biomarkers for quick and accurate monitoring of several illnesses. The aim of this pilot study was to characterize and evaluate the performance of MV as biomarker of clinical outcome in septic and trauma patients. For this purpose, 39 subjects, both genders, aging from 18 to 85 years were included in three groups referred as Sepsis, Trauma and Healthy Control. Kinetic analysis of MV was carried out at four consecutive time points: admission (baseline)/T1, 24 h/T2, 72 h/T3 and outcome/T4 of discharge or death. At admission, an overall increase in total MV (Annexin V⁺) was observed in Sepsis.MV CD14⁺ (monocytes) was a putative biomarker to identify trauma patients, while MV CD3⁺ (T-cells) and CD41⁺ (platelets) were qualified to discriminated Trauma from Sepsis. Sepsis (Death) presented an increase in MV Annexin V⁺, CD45⁺, CD16⁺, CD14⁺, and CD41+ in comparison to Sepsis (Discharge). Moreover, Trauma (Death) presented an increase of MV CD3⁺ and CD235⁺ as compared to Trauma (Discharge). Analysing the ROC curve of specific MV evaluated according to performance, an accuracy of 100% was found to segregate the outcome in sepsis, and 95% in trauma. Our findings suggest that MV might be useful as a potential role in discriminating outcome in patients with sepsis/septic shock and trauma with high accuracy. However, further studies with a larger number of participants will be necessary to validate our findings.

Bacterial Etiology of Bloodstream Infections and Antimicrobial Resistance Patterns from a Tertiary Care Hospital in Malé, Maldives

Background

Bloodstream infections pose a significant health problem worldwide and is a major cause of morbidity and mortality in many countries. It is important to have country-specific data for major pathogens causing bloodstream infections, in light of emerging resistance patterns of common bacterial isolates. Due to the scarcity of reports in this area, the aim of this study was to identify bacterial pathogens causing bloodstream infections among the study population.

Methods

A retrospective analysis of blood culture samples received at the Department of Laboratory Medicine, Indira Gandhi Memorial Hospital, Malé, Maldives, was performed for reports between January 2016 and December 2017.

Results

Out of the 471 culture-positive samples, 278 (59%) were males and 193 (41%) were females. Amongst the culture-positive samples, 338 (71.8%) Gram-positive organisms were isolated and 133 (28.2%) Gram-negative organisms were isolated. Coagulase-negative Staphylococcus (CoNS) was the most frequently isolated blood-borne bacterial pathogen in this study, accounting for 53.6% and 50.9% of the isolates in 2016 and 2017, respectively. Other frequently isolated pathogens included Staphylococcus aureus (15.9% and 10.3%), Klebsiella spp. (10.5% and 16.4%), and Escherichia coli (7.1% and 10.8%). Coagulase-negative Staphylococcus (CoNS) revealed high percentage of resistance among the tested antimicrobials, ampicillin, cephalexin, cefotaxime, and gentamicin. Over the two years, a significant difference between the percentage resistance among paediatric and adult patients was observed for coagulase-negative Staphylococcus (CoNS) isolate resistance to ampicillin (p ≤ 0.001), cephalexin (p ≤ 0.001), cefotaxime (p ≤ 0.001), gentamicin (p=0.008), and cotrimoxazole (SXT) (p ≤ 0.001). When comparing the significant antimicrobial resistance trends, it can be seen that Enterobacteriaceae isolates also demonstrated high resistance to ampicillin and gentamicin as well as second- and third-generation cephalosporins.

Conclusions

This study highlights the major bacterial pathogens involved in bloodstream infections in the healthcare setting of Malé, Maldives, and antibiotic resistance patterns. The results indicate that further characterization of bacteremia and its resistance patterns is needed to combat bloodstream infections.

Preoperative Midstream Urine Cultures vs Renal Pelvic Urine Culture or Stone Culture in Predicting Systemic Inflammatory Response Syndrome and Urosepsis After Percutaneous Nephrolithotomy: A Systematic Review and Meta-Analysis

Purpose: To compare preoperative midstream urine cultures (PMUC) and renal pelvic urine culture (RPUC) or stone culture (SC) in predicting systemic inflammatory response syndrome (SIRS) and urosepsis after percutaneous nephrolithotomy (PCNL). Methods: We searched the PubMed, Web of Science, and EMBASE databases up to September 1, 2020, for relevant published studies. Two authors independently confirmed whether the literatures met the inclusion criteria and collected the data from the selected literatures. A meta-analysis was performed with Review Manager Software 5.4.1. A total of 14 studies with 3540 patients were selected and analyzed in the meta-analysis. Results: Pooled data showed that SC was associated with a higher sensitivity (odds ratios [OR] 2.36, confidence interval [95% CI] 1.31-4.25; p < 0.00001), positive predictive value (PPV) (OR 1.54, 95% CI 1.18-2.01; p = 0.16) and negative predictive values (OR 1.17, 95% CI 1.01-1.37; p = 0.06) in the diagnosis of SIRS and urosepsis after PCNL, and RPUC provided a significantly higher specificity (OR 2.70, 95% CI 2.16-3.38; p = 0.07) and PPV (OR 2.17, 95% CI 1.49-3.15; p = 0.48) than PMUC in the diagnosis of SIRS and urosepsis after PCNL. Conclusion: Intraoperative SC and RPUC are more reliable than PMUC in predicting postoperative SIRS and urosepsis, identifying causative organisms, and directing antibiotic therapy for patients who underwent PCNL. PMUC, SC, and RPUC should be routinely collected for the diagnosis and management of SIRS and urosepsis after PCNL.

A Rare Case of Sphingomonas paucimobilis Spondylodiscitis Managed Surgically

Introduction:

Sphingomonas paucimobilis is an opportunistic pathogen and a rare cause of human infection. This case report shows bacteremia with pyogenic spondylodiscitis in lumbosacral spine caused by Sphingomonas and discusses its clinical diagnosis, treatment, and literature reviews.

Case Report:

Patient presented with severe low back pain, inability to walk and fever following a L5-S1 decompression elsewhere, which corresponded clinico-radiologically with a picture of a spondylodiscitis on radiographs, magnetic resonance imaging, and computed tomography. His blood culture was positive for S. paucimobilis. He was treated successfully by surgical debridement, stabilization, and fusion along with intravenous Linezolid followed by oral therapy, based on the antibiotic susceptibility profile. Repeat blood culture was negative after 7 weeks of antibiotic therapy. Patient improved symptomatically with radiographs showing good fusion at 1 year follow-up. S. paucimobilis, though a low virulence organism, is an emerging pathogen and should be dealt with cautiously.

Conclusion:

This reiterates the importance of culture as unusual organisms may be isolated and appropriate antibiotics form the mainstay of treatment.

Dental Abscess to Septic Shock: A Case Report and Literature Review

Sepsis is a leading cause of death in the United States, with a mortality rate in excess of 215,000 deaths per year. It may lead to septic shock, a complex pathophysiological process with microbial and host response events that progress to multisystem derangement. There is poor documentation of the relationship between dental infection and septic shock, with only a few case reports of septic shock secondary to dentoalveolar abscess. Presented is a case of sepsis/septic shock in a 23-year-old man with signs and symptoms of pulpal necrosis, acute apical abscess, and canine space infection that rapidly progressed to an altered mental state, hyperthermia, tachycardia, hypotension, acute respiratory failure, diarrhea, renal insufficiency, lactic acidosis, leukocytosis, and hyperglycemia. Once septic shock develops, the mortality rate is nearly 50%. Early antimicrobial intervention is associated with surviving severe sepsis, making it critical for dentists to understand local factors leading to the crisis and the signs and symptoms of the sepsis-septic shock continuum.

SSP: Early prediction of sepsis using fully connected LSTM-CNN model

BACKGROUND

Sepsis is a life-threatening condition that occurs due to the body's reaction to infections, and it is a leading cause of morbidity and mortality in hospitals. Early prediction of sepsis onset facilitates early interventions that promote the survival of suspected patients. However, reliable and intelligent systems for predicting sepsis are scarce.

METHODS

This paper presents a novel technique called Smart Sepsis Predictor (SSP) to predict sepsis onset in patients admitted to an intensive care unit (ICU). SSP is a deep neural network architecture that encompasses long short-term memory (LSTM), convolutional, and fully connected layers to achieve early prediction of sepsis. SSP can work in two modes; Mode 1 uses demographic data and vital signs, and Mode 2 uses laboratory test results in addition to demographic data and vital signs. To evaluate SSP, we have used the 2019 PhysioNet/CinC Challenge dataset, which includes the records of 40,366 patients admitted to the ICU.

RESULTS

To compare SSP with existing state-of-the-art methods, we have measured the accuracy of the SSP in 4-, 8-, and 12-h prediction windows using publicly available data. Our results show that the SSP performance in Mode 1 and Mode 2 is much higher than existing methods, achieving an area under the receiver operating characteristic curve (AUROC) of 0.89 and 0.92, 0.88 and 0.87, and 0.86 and 0.84 for 4 h, 8 h, and 12 h before sepsis onset, respectively.

CONCLUSIONS

Using ICU data, sepsis onset can be predicted up to 12 h in advance. Our findings offer an early solution for mitigating the risk of sepsis onset.

Neutrophil activity in sepsis: a systematic review

The neutrophil is an important cell in host defense against infections, acting as the first line of microorganism control. However, this cell exhibits dysregulated activity in sepsis and may contribute to the pathogenesis of the disease. This systematic review aimed to highlight the major scientific findings regarding neutrophil activity in sepsis reported in clinical and experimental research published in the last 10 years. The search was conducted in the Virtual Health Library of PAHO-WHO (BVS) and PubMed databases, and articles published between January 2007 and May 2017 in Portuguese, English, and Spanish were eligible. Article selection was carried out independently by two reviewers (CB and IB). A total of 233 articles were found, of which 87 were identified on PubMed and 146 on BVS. Eighty-two articles were duplicates. Of the remaining 151 articles, 19 met the inclusion criteria after title, abstract, and full-text analysis. Overall, research in clinical samples and animal models of sepsis showed reduced capacity of neutrophils to migrate and delayed apoptosis, but there was no consensus on the phagocytic activity of neutrophils in sepsis. Molecules, such as pentraxin 3 (PTX3), have been analyzed as potential diagnostic markers in sepsis but the diversity of soluble molecules detected in blood samples of sepsis patients did not enable further understanding of the correlation of these circulating molecules with neutrophil activity during sepsis. Optimal understanding of the function of neutrophils in sepsis remains a challenge that, if overcome, would eventually allow targeted therapeutic interventions in patients affected by this severe syndrome.

Reconstituted High-density Lipoprotein Therapy Improves Survival in Mouse Models of Sepsis

BACKGROUND

High-density lipoproteins exert pleiotropic effects including antiinflammatory, antiapoptotic, and lipopolysaccharide-neutralizing properties. The authors assessed the effects of reconstituted high-density lipoproteins (CSL-111) intravenous injection in different models of sepsis.

METHODS

Ten-week-old C57BL/6 mice were subjected to sepsis by cecal ligation and puncture or intraperitoneal injection of Escherichia coli or Pseudomonas aeruginosa pneumonia. CSL-111 or saline solution was administrated 2 h after the sepsis. Primary outcome was survival. Secondary outcomes were plasma cell-free DNA and cytokine concentrations, histology, bacterial count, and biodistribution.

RESULTS

Compared with saline, CSL-111 improved survival in cecal ligation and puncture and intraperitoneal models (13 of 16 [81%] survival rate vs. 6 of 16 [38%] in the cecal ligation and puncture model; P = 0.011; 4 of 10 [40%] vs. 0 of 10 [0%] in the intraperitoneal model; P = 0.011). Cell-free DNA concentration was lower in CSL-111 relative to saline groups (68 [24 to 123] pg/ml vs. 351 [333 to 683] pg/ml; P < 0.001). Mice injected with CSL-111 presented a decreased bacterial count at 24 h after the cecal ligation and puncture model both in plasma (200 [28 to 2,302] vs. 2,500 [953 to 3,636] colony-forming unit/ml; P = 0.021) and in the liver (1,359 [360 to 1,648] vs. 1,808 [1,464 to 2,720] colony-forming unit/ml; P = 0.031). In the pneumonia model, fewer bacteria accumulated in liver and lung of the CSL-111 group. CSL-111-injected mice had also less lung inflammation versus saline mice (CD68+ to total cells ratio: saline, 0.24 [0.22 to 0.27]; CSL-111, 0.07 [0.01 to 0.09]; P < 0.01). In all models, no difference was found for cytokine concentration. Indium bacterial labeling underlined a potential hepatic bacterial clearance possibly promoted by high-density lipoprotein uptake.

CONCLUSIONS

CSL-111 infusion improved survival in different experimental mouse models of sepsis. It reduced inflammation in both plasma and organs and decreased bacterial count. These results emphasized the key role for high-density lipoproteins in endothelial and organ protection, but also in lipopolysaccharide/bacteria clearance. This suggests an opportunity to explore the therapeutic potential of high-density lipoproteins in septic conditions.

The Utility of Early Warning Score in Adults Presenting With Sepsis in the Emergency Department of a Low Resource Setting

Background

Sepsis is a condition with high mortality and morbidity. Delay in early recognition and prompt management results in higher mortality. There are many clinical scores to identify early sepsis; however, Early Warning Score (EWS) has clinical/physiological parameters that are easy to apply in the ED for timely diagnosis and management. In the present study, we collected information regarding the utilization of EWS in timely identifying the sick patients at triage of a tertiary care center.

Methods

This study was a descriptive cross-sectional investigation conducted in the ED of Aga Khan University Hospital in Karachi, the largest metropolitan city in Pakistan. A total of 240 participants were selected by non-probability convenient sampling after fulfilling the inclusion criteria. Data collected included EWS criteria, demography, length of hospital stay, patient disposition (ward, intensive care or high dependency area), and differentials like sepsis, severe sepsis or septic shock.

Results

A total of 240 patients were enrolled, out of which 139 (57.9%) patients were male, and 101 (42.1%) were female with a mean age of 52.7 ± 15.3 years (range: 18 to 80 years). In this study, the length of stay (LOS) was 2.2 ± 1.1 (range: one to six days), and there was an EWS of 8.2 ± 2.6 (4-15). There were 143 patients in the elderly age group > 50 years (59.6%); however, most elderly presented with sepsis among both age groups. The least affected age group was aged 16 to 30 years, with 23 (9.6%) cases. An EWS >7 is best to detect cases with sepsis or severe sepsis with a sensitivity of 98.5% (95% CI: 92.13 to 99.92) and specificity of 89.57% (95% CI: 82.64 to 93.93). Similarly, the EWS for severe sepsis or septic shock was >9 with a sensitivity of 86.76% (95% CI: 76.72 to 92.88) and specificity of 88.24% (95% CI: 78.47 to 93.92).

Conclusions

This study revealed that the sensitivity and specificity of EWS for the detection of sepsis, severe sepsis and septic shock was found to be high; hence, it could be a valuable and readily useable system for early diagnosis and proper management of sepsis, severe sepsis, and septic shock.

C Reactive Protein and Procalcitonine as Diagnostic Markers in Critically Ill Patients with Suspected Sepsis

The primary aim of this retrospective study was to estimate significance of determining C-reactive protein and procalcitonine for a diagnosis of sepsis in adult patients in early triage. Also, the aim of this study was to measure the sensitivity of the SIRS criteria, PCT and CRP levels and sepsis definitions to identify the most serious sepsis cases in the prehospital setting and at the Emergency Department (ED) triage. All patients were divided into two groups according to specific criteria for defining sepsis. First group (SIRS+ group) of patients were patients with clinically and/or laboratory confirmed sepsis (or systemic inflammatory response syndrome (SIRS) to bacterial infection with different localization). For confirmation of the SIRS we consider positive two or more clinical criteria (≥2 clinical criteria). The SIRS criteria use the clinical criteria of the Surviving Sepsis Campaign (SSC) for the SIRS, comprising at least two of the following criteria: HR > 90/min, RR > 20/min and temperature < 36° or ≥ 38.3°C and the next laboratory parameters such as leucocytosis > 15x109/L, leucopenia < 4x109/L, > 10% immature leucocytes. Second group of patients were patients with the SIRS negative criteria as a diagnostic tool (SIRS- group). We have founded that the CRP showed high sensitivity but no specificity in patients with sepsis, but on the other side, the PCT as a diagnostic marker showed a high sensitivity and high specificity in these patients. Also, the PCT is in positive correlation with the SIRS criteria, which could be of a clinical significance in early diagnosis of septic infections.

Red Ginseng Reduces Inflammatory Response via Suppression MAPK/P38 Signaling and p65 Nuclear Proteins Translocation in Rats and Raw 264.7 Macrophage

Lipopolysaccharides (LPS) cause systemic inflammatory responses, which are characterized by high mortality and multiple signs, including metabolic disturbances, respiratory acidosis, hypotension, and vital organs disorder. Cytokines secretion and oxidative stress are the main features of the disease. Diagnosis and treatment of systemic inflammation (SI) remain a challenge. Korean Red Ginseng (RG) is one of medicinal herbs that showed a potent anti-oxidant effect. We aimed to study the protective effects of RG on systemic inflammatory response in rats and RAW 264.7 macrophage cells induced by LPS. The rats were treated with water and alcohol extracts of RG for four weeks to prevent the inflammatory response. The result showed that LPS toxin increased morbidity and mortality, and induced liver, kidney, and lung injuries manifested by deteriorated biomarkers. Hypotension, hypomagnesemia, acidosis, and oxidative stress were observed in septic rats. However, RG extracts attenuated liver, kidney, and lung enzymes and metabolites in treated groups via its anti-inflammatory and anti-oxidant properties. Furthermore, RG improved magnesium and blood pressure in the treated groups. RAW 264.7 macrophage cells exposed to LPS disturbance in translocation of p65 and MAPK/p38. Nevertheless, RG-pretreated cells did not significantly alter. In conclusion, RG reduced the rates of mortality and morbidity of treated rats - liver, kidney, and lung injuries were protected in the treated groups through the potentiation of anti-oxidant defense. RG was able to conserve mitochondrial function, inhibiting the activation of MAPK/p38 signaling and suppressing NF-κB p65 cytoplasm-nucleus transport. Further studies are needed to examine the effects on chronic conditions in animal models and human.

Peroxynitrite decomposition catalyst reduces vasopressin requirement in ovine MRSA sepsis

Background

Sepsis is one of the most frequent causes of death in the intensive care unit. Host vascular hypo-responsiveness to vasopressors during septic shock is one of the challenging problems. This study tested the hypothesis that adjunct therapy with peroxynitrite decomposition catalyst (WW-85) would reduce arginine vasopressin (AVP) requirements during sepsis resuscitation, using ovine sepsis model.

Methods

Thirteen adult female Merino sheep, previously instrumented with multiple vascular catheters, were subjected to “two-hit” (cotton smoke inhalation and intrapulmonary instillation of live methicillin-resistant Staphylococcus aureus; 3.5 × 10¹¹ colony-forming units) injury. Post injury, animals were awakened and randomly allocated to the following groups: (1) AVP: injured, fluid resuscitated, and titrated with AVP, n = 6 or (2) WW-85 + AVP: injured, fluid resuscitated, treated with WW-85, and titrated with AVP, n = 7. One-hour post injury, a bolus intravenous injection of WW-85 (0.1 mg/kg) was followed by a 23-h continuous infusion (0.02 mg/kg/h). Titration of AVP started at a dose of 0.01 unit/min, when mean arterial pressure (MAP) decreased by 10 mmHg from baseline, despite aggressive fluid resuscitation, and the rate was further adjusted to maintain MAP. After the injury, all animals were placed on a mechanical ventilator and monitored in the conscious state for 24 h.

Results

The injury induced severe hypotension refractory to aggressive fluid resuscitation. High doses of AVP were required to partially attenuate the sepsis-induced hypotension. However, the cumulative AVP requirement was significantly reduced by adjunct treatment with WW-85 at 17–24 h after the injury (p < 0.05). Total AVP dose and the highest AVP rate were significantly lower in the WW-85 + AVP group compared to the AVP group (p = 0.02 and 0.04, respectively). Treatment with WW-85 had no adverse effects. In addition, the in vitro effects of AVP on isolated artery diameter changes were abolished with peroxynitrite co-incubation.

Conclusions

The modulation of reactive nitrogen species, such as peroxynitrite, may be considered as a novel adjunct treatment option for septic shock associated with vascular hypo-responsiveness to vasopressors.

Multiorgan dysfunction syndrome in feline sepsis: prevalence and prognostic implication

OBJECTIVES

The current study was designed to evaluate the prevalence and prognostic significance of multiorgan dysfunction syndrome (MODS) in cats with sepsis.

METHODS

Cats hospitalised in the intensive care unit of a veterinary university hospital with a diagnosis of sepsis were prospectively enrolled and divided according to disease severity and outcome (survivors; non-survivors). The feline acute patient physiological and laboratory evaluation (APPLE) scores were calculated upon admission, as previously described. Specific criteria to identify selected organ dysfunction (hepatic, renal, respiratory, cardiocirculatory, haemostatic) were adapted from the available human and veterinary literature, and evaluated at baseline and at the end of hospital stay. MODS was defined as the presence of at least two dysfunctional organs simultaneously. Non-parametric statistics were used for comparisons. Univariate and multivariate regression analyses to evaluate significant risk factors for death were carried out. Correlations between variables were assessed by the Spearman's rank correlation coefficient. Significance was set at P <0.05.

RESULTS

A total of 43 cats with heterogeneous sources of sepsis were included. MODS was identified in 25/43 cats upon admission and in 32/43 cats at the end of hospital stay. Regression analyses showed a significantly elevated odds ratio for mortality for the presence of MODS, renal and cardiovascular dysfunction upon admission, as well as for the number of dysfunctional organs. The latter was the only variable retained by the model from the multivariate binary logistic regression analysis. Significant correlations were documented between the number of dysfunctional organs and the APPLE scores.

CONCLUSIONS AND RELEVANCE

MODS is a frequent complication of feline sepsis, and is associated with worse outcomes. In particular, renal and cardiovascular dysfunction significantly increase the odds for death. Hence, systematic screening for organ dysfunction is advocated in cats with sepsis.

Metabolic regulation of inflammasomes in inflammation

Inflammasome activation and subsequent inflammatory cytokine secretion are essential for innate immune defence against multiple stimuli and are regarded as a link to adaptive immune responses. Dysfunction of inflammasome activation has been discovered at the onset or progression of infectious diseases, autoimmune diseases and cancer, all of which are also associated with metabolic factors. Furthermore, many studies concerning the metabolic regulation of inflammasome activation have emerged in recent years, especially regarding the activity of the NLRP3 inflammasome under metabolic reprogramming. In this review, we discuss the molecular mechanisms of the interactions between metabolic pathways and inflammasome activation, which exerts further important effects on various diseases.

Liquid chromatography-tandem mass spectrometry based method development and validation of S016-1271 (LR8P), a novel cationic antimicrobial peptide for its application to pharmacokinetic studies

S016-1271 (LR8P) is a broad spectrum novel cationic antimicrobial peptide. The objective of the present study was to develop a selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) based bioanalytical method of S016-1271 peptide in mice and human plasma in order to uncover its pharmacokinetic aspects. The chromatographic separation of S016-1271 (FR8P as internal standard) was achieved on a Waters™ X select CSH-C18 column (75 × 3.0 mm, 2.5 μ) using mixture of acetonitrile and triple distilled water (TDW) both containing 0.05% formic acid as mobile phase. A seven minute linear gradient method was designed to separate analytes from ion suppression at a flow rate of 0.3 mL/min. The extraction of analytes from mice and human plasma was performed through solid phase extraction technique using mixed mode weak cation exchange cartridge (Thermo SOLA WCX 10 mg 1CC) with an extraction recovery of analytes about 75%. Mass spectrometric detection of S016-1271 and FR8P was performed with optimized multiple reaction monitoring (MRM) transitions (Q1/Q3) at 658.8 [M+3H] ³⁺/653.2 [M+3H-NH₃] ³⁺ and 443.4 [M+5H]⁵⁺ /434.7 [y₁₂-NH₃]⁴⁺,respectively in positive electrospray ionization (ESI) mode. The linearity in mice and human plasma was established over a concentration range of 7.81-250 ng/mL with regression coefficient (r² > 0.99). The currently developed method was validated as per US-FDA guidelines and found to be within the acceptable limits. The method was successfully applied to intravenous (IV) pharmacokinetic study in mice wherein the levels were detected upto 24 h. The peptide demonstrated poor distribution characteristics which were demonstrated through volume of distribution at steady state (202.71 ± 47.02 mL/kg less than total body water of mice; 580 mL/kg). The clearance of the peptide predominantly occurred through central compartment (central clearance is 25 fold greater than peripheral clearance). Also, the in vitro pharmacokinetic studies demonstrated the stability of S016-1271 in plasma and high plasma protein binding in mice and humans.

The use of initial dosing of gentamicin in the management of pyelonephritis/urosepsis: A retrospective study

Objective

The primary objective was to determine if initial empirical intravenous dosing of gentamicin improved patient's outcomes in pyelonephritis/urosepsis compared with alternative IV antibiotic management.

Design

Retrospective cross-sectional descriptive study.

Setting

Public TertiaryTeaching Hospital serving adults in an urban centre.

Participants

All adult patient records with a recorded diagnosis of any of pyelonephritis/urosepsis, urinary tract infection, UTI, complicated urinary tract infection, bacteriuria, symptomatic bacteriuria and asymptomatic bacteriuria from 2^nd February 2012 to 10^th May 2014 were reviewed. Only patients treated with an empirical regimen of one or more IV antibiotics were included in the study.

Main outcomes

The primary outcomes were: duration of IV antibiotic treatment, time to resolution of symptoms and length of hospital stay (LOS). Secondary end points were: compliance with Therapeutic Guidelines: Antibiotic (electronic version) (eTG) for severe pyelonephritis/urosepsis and appropriateness of gentamicin use.

Data analysis

Univariate and multivariable associations between baseline and demographic variables and the main outcomes were performed using Chi-square tests and a General Linear Model using the SAS version 9.2 software.

Results

Of 295 patients reviewed 152 were prescribed one or more IV antibiotics and included in the study. Approximately half of the patients (n = 73, 48%) were prescribed IV piperacillin/tazobactam (Tazocin), while gentamicin was prescribed for 66 patients (43.4%). Of the 152 patients evaluated, 49 (32%) were given gentamicin first. Multivariable regression analysis showed that duration of IV treatment was shorter for those aged over 70 (40.2 hours vs 85.5 hours for those aged up to 70; p = 0.0074), and those who received gentamicin as first line treatment (41.3 hours vs 89.8 hours for those not receiving any gentamicin; p = 0.0312). After adjustment for age and gentamicin administration, there appeared to be no significant difference in duration of IV treatment for any other independent variables. No significant associations between the independent variables (gentamicin, age, gender, comorbidities, and eTG compliance) and either time to resolution of symptoms (median: 68 hours) or hospital LOS (median: 5 days) were observed.

Conclusions

Neither time to resolution of abnormal symptoms nor length of stay were significantly influenced by an initial dose of gentamicin when the data were subjected to multivariable analysis. The age of the patient and pattern of gentamicin treatment were the dominant factors associated with duration of IV antibiotics. Piperacillin/tazobactam is not recommended in treatment guidelines for pyelonephritis/urosepsis but was the most commonly prescribed IV antibiotic. This requires review by the appropriate hospital clinicians.

A New Method Aimed to Quickly Identify Pathogen and Drug Susceptibility Test Based on Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry Combined with Flow Cytometry

AIM

To discuss the significance and applied value in the rapid identification and drug susceptibility test for blood stream infection (BSI) using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) combined with flow cytometry (FCM).

METHODS

The bacteria were separated from the positive blood culture bottle using the separation gel-adsorption method system, and then applying MALDI-TOF MS combined with FCM to identify pathogen and drug susceptibility test quickly.

RESULTS

The efficiency of the separation gel-adsorption method for gram-negative bacterium, gram-positive bacteria, and fungi is 71%, 74%, and 88%, respectively. The results of identifying pathogens using MALDI-TOFMS are in agreement with results obtained using VITEK^®2 (bioMérieux, Marcy l'Etoile, France); both methods can identify 90% of bacteria to species. For fungi, MALDI-TOF MS can identify 75% fungi to species, which is superior to VITEK2, which identifies 60% fungi to species. The results of drug susceptibility test using FCM are almost identical to VITEK2; additionally, the addition of fluorescein diacetate can identify the heterogenic drug-resistant strains.

CONCLUSIONS

We can quickly identify pathogen and drug-susceptibility test based on MALDI-TOF MS combined with FCM, which is consistent with traditional methods and can shorten the report time from 36-72 hour to 3 hours. More importantly, these methods are of great significance and clinical importance for the rapid identification of BSI.

High levels of circulating GM-CSF+CD4+ T cells are predictive of poor outcomes in sepsis patients: a prospective cohort study

Granulocyte colony-stimulating factor (GM-CSF), produced by CD4⁺ T cells, has recently been implicated in the pathogenesis of inflammatory diseases, such as multiple sclerosis and juvenile arthritis. However, the role of GM-CSF-producing CD4⁺ T cells in sepsis remains unknown. This study reports peripheral changes in GM-CSF-producing CD4⁺ T cells in septic patients and the possible underlying mechanism by which GM-CSF influences the outcome of sepsis. Forty-three septic patients, 20 SIRS patients, and 20 healthy controls were enrolled in this study and followed for 28 days to assess mortality. We measured the peripheral frequency of GM-CSF⁺CD4⁺ T cells and recorded their associated relationship with disease progression. Our data demonstrated that peripheral GM-CSF-producing CD4⁺ T cells were significantly higher in septic patients than in both SIRS patients and healthy controls. These cells exhibit a memory phenotype and impaired IFN-γ-secreting capacity in sepsis patients. Using a receiver operating curve analysis with 8.01% as a cut-off point, the percentage of GM-CSF⁺CD4⁺ T cells could predict the outcome of septic patients^. Combined with the increase in GM-CSF-producing CD4⁺ T cells, inflammatory cytokines IL-1β and IL-6 were also upregulated. Using an in vitro neutrophil model, we found that GM-CSF inhibited C3aR expression, while inducing IL-8 production. Furthermore, this effect was transferrable in plasma from sepsis patients and was attenuated by inhibition of GM-CSF using an anti-GM-CSF antibody. These results indicate that GM-CSF-producing CD4⁺ T cells may serve as a marker of sepsis severity. Thus, targeting GM-CSF overproduction may benefit sepsis patients.

Fabrication of fasudil hydrochloride modified graphene oxide biocomposites and its defensive effect acute renal injury in septicopyemia rats

This investigation aspired to the impacts of intraperitoneal injection of suspended graphene oxide-bovine serum albumin (GO-BSA) biocomposite blended in fasudil (FSD)-against intense renal damage in septicopyemia rodent's models. It was picked a model of acute renal injury by an intraperitoneal organization of fasudil. Our outcomes demonstrated that few markers of renal capacity, for example, blood urea nitrogen (BUN), creatinine (SC), and intratubular waste levels were altogether diminished essentially in fasudil blended GO-BSA intraperitoneally infusion groups during the first week, showing that GO-BSA has an uncommon ability to ensure FSD discharges. Additionally, surprisingly, while rats got GO-BSA intraperitoneally, biomedical examination demonstrated the fruitful decrease of blood urea nitrogen and creatinine blood factors showing that GO-BSA has an uncommon ability alone to repair the acute renal injury. It appears that GO-BSA can adsorb ECM proteins and encourages their exchange to the intense renal damage tissue and expands its repair speed, in addition, GO-BSA ensures the FSD and along these lines the helpful adequacy of the FSD in intense renal damage enhanced by the grip of living cells to GO-BSA biocomposites. It could be inferred that GO-BSA material improves the rate of achievement of FSD conveys in intense renal damage in septicopyemia animals.

Effect of a machine learning-based severe sepsis prediction algorithm on patient survival and hospital length of stay: a randomised clinical trial

Introduction

Several methods have been developed to electronically monitor patients for severe sepsis, but few provide predictive capabilities to enable early intervention; furthermore, no severe sepsis prediction systems have been previously validated in a randomised study. We tested the use of a machine learning-based severe sepsis prediction system for reductions in average length of stay and in-hospital mortality rate.

Methods

We conducted a randomised controlled clinical trial at two medical-surgical intensive care units at the University of California, San Francisco Medical Center, evaluating the primary outcome of average length of stay, and secondary outcome of in-hospital mortality rate from December 2016 to February 2017. Adult patients (18+) admitted to participating units were eligible for this factorial, open-label study. Enrolled patients were assigned to a trial arm by a random allocation sequence. In the control group, only the current severe sepsis detector was used; in the experimental group, the machine learning algorithm (MLA) was also used. On receiving an alert, the care team evaluated the patient and initiated the severe sepsis bundle, if appropriate. Although participants were randomly assigned to a trial arm, group assignments were automatically revealed for any patients who received MLA alerts.

Results

Outcomes from 75 patients in the control and 67 patients in the experimental group were analysed. Average length of stay decreased from 13.0 days in the control to 10.3 days in the experimental group (p=0.042). In-hospital mortality decreased by 12.4 percentage points when using the MLA (p=0.018), a relative reduction of 58.0%. No adverse events were reported during this trial.

Conclusion

The MLA was associated with improved patient outcomes. This is the first randomised controlled trial of a sepsis surveillance system to demonstrate statistically significant differences in length of stay and in-hospital mortality.

Trial registration

NCT03015454.

Can neutrophil to lymphocyte ratio predict late-onset sepsis in preterm infants?

BACKGROUND

The neutrophil to lymphocyte ratio (NLR) is an easily accessible biomarker that has been reported to represent disease severity in adult trials. The aim of this study was to evaluate the relationship between culture positiveness and NLR in cases where the reason of sepsis was considered, and to foresight an idea about the active agents.

METHODS

Preterm infants with birth weights ≤1500 g and/or ≤32 gestational weeks were eligible for this study. The postnatal age of all included infants was more than 3 days with clinical and laboratory signs of sepsis. According to the results of blood cultures, all enrolled infants were classified into 2 groups: the culture-proven septic infants and suspected septic infants. The NLR was calculated as the ratio of neutrophil count to lymphocyte count. Initial laboratory investigations included WBC count, platelet count (PLT), C-reactive protein (CRP), and blood cultures.

RESULTS

A total of 127 infants were involved: 57 culture-proven sepsis and 75 suspected sepsis. There were no significant differences between groups regarding gestational age, gender, birth weight, delivery mode, and postnatal age. Receiver operating curve analysis for NLR and CRP was calculated. The area under the curve corresponded to 0.78 ± 0.04 (NLR) vs 0.55 ± 0.05 (CRP). Using a cutoff point of 1.77 for NLR, the sensitivity was 0.73, the specificity was 0.78, and accuracy rate was 0.76.

DISCUSSION

The prediction of NLR, an easy, inexpensive, and rapid method, along with CRP in the neonatal period for diagnosis of sepsis, will be more effective in detecting culture-proven sepsis and in decreasing unnecessary antibiotherapy.

An AAAG-Rich Oligodeoxynucleotide Rescues Mice from Bacterial Septic Peritonitis by Interfering Interferon Regulatory Factor 5

A previous study found that an AAAG-rich Oligodeoxynucleotide (ODN), designated as MS19, could lessen the acute lung inflammatory injury (ALII) in mice infected by influenza viruses. Bioinformatics analysis found that MS19 is consensus with the binding site of interferon regulatory factor 5 (IRF5) in the regulatory elements of pro-inflammatory genes. This study established a septic peritonitis model in Institute of Cancer Research (ICR) mice infected with Escherichia coli (E. coli), and found that MS19 prolonged the survival of the mice and down-regulated the expression of inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α). In cultured RAW264.7 cells, MS19 significantly reduced the expression of iNOS, IRF5, IL-6, and TNF-α and inhibited the nuclear translocation of IRF5. This data may provide a new insight for understanding how MS19 reduces the excessive inflammatory responses in sepsis.

Sepsis and septic shock: Pathogenesis and treatment perspectives

The majority of bacteremias do not develop to sepsis: bacteria are cleared from the bloodstream. Oxygen released from erythrocytes and humoral immunity kill bacteria in the bloodstream. Sepsis develops if bacteria are resistant to oxidation and proliferate in erythrocytes. Bacteria provoke oxygen release from erythrocytes to arterial blood. Abundant release of oxygen to the plasma triggers a cascade of events that cause: 1. oxygen delivery failure to cells; 2. oxidation of plasma components that impairs humoral regulation and inactivates immune complexes; 3. disseminated intravascular coagulation and multiple organs' failure. Bacterial reservoir inside erythrocytes provides the long-term survival of bacteria and is the cause of ineffectiveness of antibiotics and host immune reactions. Treatment perspectives that include different aspects of sepsis development are discussed.

Earlier versus later initiation of renal replacement therapy among critically ill patients with acute kidney injury: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Although the optimal timing of initiation of renal replacement therapy (RRT) in critically ill patients with acute kidney injury has been extensively studied in the past, it is still unclear.

METHODS

In this systematic review, we searched all related randomized controlled trials (RCTs) that directly compared earlier and later RRT published prior to June 25, 2016, from PubMed, MEDLINE, and EMBASE. We extracted the study characteristics and outcomes of all-cause mortality, RRT dependence, and intensive care unit (ICU) and hospital length of stay (LOS).

RESULTS

We identified 51 published relevant studies from 13,468 screened abstracts. Nine RCTs with 1627 participants were included in this meta-analysis. Earlier RRT was not associated with benefits in terms of mortality [relative risk (RR) 0.88, 95% confidence interval (CI) 0.68-1.14, p = 0.33] and RRT dependence (RR 0.81, 95% CI 0.46-1.42, p = 0.46). There were also no significant differences in the ICU and hospital LOS between patients who underwent earlier versus later RRT [standard means difference -0.08 (95% CI -0.26 to 0.09) and -0.11 (95% CI -0.37 to 0.16) day, respectively]. In subgroup analysis, earlier RRT was associated with a reduction in the in-hospital mortality among surgical patients (RR 0.78, 95% CI 0.64-0.96) and patients who underwent continuous renal replacement therapy (CRRT) (RR 0.80, 95% CI 0.67-0.96).

CONCLUSIONS

Compared with later RRT, earlier initiation of RRT did not show beneficial impacts on patient outcomes. However, a lower rate of death was observed among surgical patients and in those who underwent CRRT. The included literature is highly heterogeneous and, therefore, potentially subject to bias. Further high-quality RCT studies are warranted.

Amelioration of energy metabolism by melatonin in skeletal muscle of rats with LPS induced endotoxemia

In the literature, few studies have investigated the effects of melatonin on energy metabolism in skeletal muscle in endotoxemia. We investigated the effects of melatonin on tissue structure, energy metabolism in skeletal muscle, and antioxidant level of rats with endotoxemia. We divided rats into 4 groups, control, lipopolysaccharide (LPS) (20 mg/kg, i.p., single dose), melatonin (10 mg/kg, i.p., three times), and melatonin + LPS. Melatonin was injected i.p. 30 min before and after the 2nd and 4th hours of LPS injection. Antioxidant status was determined by glutathione (GSH) measurement in the blood. Muscle tissue was stained using modified Gomori trichrome (MGT), succinic dehydrogenase (SDH), and cytochrome oxidase (COX) and histological scored. Also the sections were then stained with hematoxylin and eosin. The stained sections were visualized and photographed. Creatine, creatine phosphate, adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP) levels were investigated using high performance liquid chromatography (HPLC) in muscle tissue. In the Melatonin + LPS group, blood GSH levels were increased compared with the LPS group (P<0.01). Melatonin reduced myopathic changes in the LPS group according to the histopathologic findings. In addition, ATP values were increased compared with the LPS group (P<0.05). Our findings showed melatonin treatment prevented muscle damage by increasing ATP and GSH levels in rats with LPS induced endotoxemia.

Effects of statins on the development of sepsis and organ dysfunction in hospitalized older patients in China

This study aimed to evaluate the protective role of statins on the development of sepsis and infection-related organ dysfunction and mortality in a hospitalized older Chinese population with bacterial infections. In this retrospective cohort study, 257 older patients with bacterial infection were divided into two groups: a statin group, those who had received statin therapy for ≥1 month before admission and continued receiving statin during hospitalization; and a non-statin group, those who had never received statin or used statin for <1 month prior to admission. A multivariate logistic regression analysis was performed to identify risk and protective factors for severe sepsis. A significantly lower incidence of organ dysfunction was found in the statin group, as compared with the non-statin group (13.3% vs 31.1%, respectively; p = 0.002), corresponding to adjusted rates ratio of 0.32 (95% confidence interval [CI], 0.13–0.75; p = 0.009). No significant difference was found between statin and non-statin groups in 30-day sepsis-related mortality (4.4% vs 10.2%, respectively; p = 0.109), incidence of intensive care unit admission (13.3% vs 16.8%, respectively; p = 0.469), or length of hospital stay (20.5 vs 25.9 days, respectively; p = 0.61). Statins significantly reduced the development of sepsis and infection-related organ dysfunction in hospitalized older Chinese patients but did not reduce 30-day mortality, ICU admission incidence, or length of hospital stay.

Evaluation of Two Methods for Determination of CD64 as a Diagnostic Marker of Infection in Critically Ill Adults

Objectives. Diagnostic markers of infection have had little innovation over the last few decades. CD64, a marker expressed on the surface of neutrophils, may have utility for this purpose. Methods. This study was conducted in an adult intensive care unit (ICU) in São Paulo, Brazil, with 89 patients. We evaluated CD64 in patients with documented or clinically diagnosed infection (infection group) and controls (patients without any evidence of infection) by two different methodologies: method #1, an in house assay, and method #2, the commercial kit Leuko64 (Trillium Diagnostics). Results. CD64 displayed good discriminating power with a 91.2% sensitivity (95% CI 90.7–91.6%) for detecting infection. The commercial kit (Leuko64) demonstrated higher specificity (87.3%) compared with method #1 as well as better accuracy (88.8%). Conclusions. CD64 seems to be a promising marker of infection in the intensive care setting, with Leuko64 showing a slight advantage.

Postoperative sepsis prediction in patients undergoing major cancer surgery

BACKGROUND

Cancer patients are at increased risk for postoperative sepsis. However, studies addressing the issue are lacking. We sought to identify preoperative and intraoperative predictors of 30-d sepsis after major cancer surgery (MCS) and derive a postoperative sepsis risk stratification tool.

METHODS

Patients undergoing one of nine MCSs (gastrointestinal, urological, gynecologic, or pulmonary) were identified within the American College of Surgeons National Surgical Quality Improvement Program (2005-2011, n = 69,169). Multivariable adjusted analyses (MVA) were performed to identify the predictors of postoperative sepsis. A composite sepsis risk score (CSRS) was constructed using the regression coefficients of predictors significant on MVA. The score was stratified into low, intermediate, and high risk, and its predictive accuracy for sepsis, septic shock, and mortality was assessed using the area under the curve analysis.

RESULTS

Overall, 4.3% (n = 2954) of patients developed postoperative sepsis. In MVA, Black race (odds ratio [OR] = 1.30, P = 0.002), preoperative hematocrit <30 (OR = 1.40, P = 0.022), cardiopulmonary and cerebrovascular comorbidities (P < 0.010), American Society of Anesthesiologists score >3 (P < 0.05), operative time (OR = 1.002, P < 0.001), surgical approach (OR = 1.81, P < 0.001), and procedure type (P < 0.001) were significant predictors of postoperative sepsis. CSRS demonstrated favorable accuracy in predicting postoperative sepsis, septic shock, and mortality (area under the curve 0.72, 0.75, and 0.74, respectively). Furthermore, CSRS risk stratification demonstrated high concordance with sepsis rates, 1.3% in low-risk patients versus 9.7% in high-risk patients. Similarly, 30-d mortality rate varied from 0.5% to 5.5% (10-fold difference) in low-risk patients versus high-risk patients.

CONCLUSIONS

Our study identifies the major risk factors for 30-d sepsis after MCS. These risk factors have been converted into a simple, accurate bedside sepsis risk score. This tool might facilitate improved patient-physician interaction regarding the risk of postoperative sepsis and septic shock.

Prediction of Sepsis in the Intensive Care Unit With Minimal Electronic Health Record Data: A Machine Learning Approach

Background

Sepsis is one of the leading causes of mortality in hospitalized patients. Despite this fact, a reliable means of predicting sepsis onset remains elusive. Early and accurate sepsis onset predictions could allow more aggressive and targeted therapy while maintaining antimicrobial stewardship. Existing detection methods suffer from low performance and often require time-consuming laboratory test results.

Objective

To study and validate a sepsis prediction method, InSight, for the new Sepsis-3 definitions in retrospective data, make predictions using a minimal set of variables from within the electronic health record data, compare the performance of this approach with existing scoring systems, and investigate the effects of data sparsity on InSight performance.

Methods

We apply InSight, a machine learning classification system that uses multivariable combinations of easily obtained patient data (vitals, peripheral capillary oxygen saturation, Glasgow Coma Score, and age), to predict sepsis using the retrospective Multiparameter Intelligent Monitoring in Intensive Care (MIMIC)-III dataset, restricted to intensive care unit (ICU) patients aged 15 years or more. Following the Sepsis-3 definitions of the sepsis syndrome, we compare the classification performance of InSight versus quick sequential organ failure assessment (qSOFA), modified early warning score (MEWS), systemic inflammatory response syndrome (SIRS), simplified acute physiology score (SAPS) II, and sequential organ failure assessment (SOFA) to determine whether or not patients will become septic at a fixed period of time before onset. We also test the robustness of the InSight system to random deletion of individual input observations.

Results

In a test dataset with 11.3% sepsis prevalence, InSight produced superior classification performance compared with the alternative scores as measured by area under the receiver operating characteristic curves (AUROC) and area under precision-recall curves (APR). In detection of sepsis onset, InSight attains AUROC = 0.880 (SD 0.006) at onset time and APR = 0.595 (SD 0.016), both of which are superior to the performance attained by SIRS (AUROC: 0.609; APR: 0.160), qSOFA (AUROC: 0.772; APR: 0.277), and MEWS (AUROC: 0.803; APR: 0.327) computed concurrently, as well as SAPS II (AUROC: 0.700; APR: 0.225) and SOFA (AUROC: 0.725; APR: 0.284) computed at admission (P<.001 for all comparisons). Similar results are observed for 1-4 hours preceding sepsis onset. In experiments where approximately 60% of input data are deleted at random, InSight attains an AUROC of 0.781 (SD 0.013) and APR of 0.401 (SD 0.015) at sepsis onset time. Even with 60% of data missing, InSight remains superior to the corresponding SIRS scores (AUROC and APR, P<.001), qSOFA scores (P=.0095; P<.001) and superior to SOFA and SAPS II computed at admission (AUROC and APR, P<.001), where all of these comparison scores (except InSight) are computed without data deletion.

Conclusions

Despite using little more than vitals, InSight is an effective tool for predicting sepsis onset and performs well even with randomly missing data.

Antimicrobial susceptibility testing of Gram-positive and -negative bacterial isolates directly from spiked blood culture media with Raman spectroscopy

Patients suffering from bacterial bloodstream infections have an increased risk of developing systematic inflammatory response syndrome (SIRS), which can result in rapid deterioration of the patients' health. Diagnostic methods for bacterial identification and antimicrobial susceptibility tests are time-consuming. The aim of this study was to investigate whether Raman spectroscopy would be able to rapidly provide an antimicrobial susceptibility profile from bacteria isolated directly from positive blood cultures. First, bacterial strains (n = 133) were inoculated in tryptic soy broth and incubated in the presence or absence of antibiotics for 5 h. Antimicrobial susceptibility profiles were analyzed by Raman spectroscopy. Subsequently, a selection of strains was isolated from blood cultures and analyzed similarly. VITEK®2 technology and broth dilution were used as the reference methods. Raman spectra from 67 antibiotic-susceptible strains showed discriminatory spectra in the absence or at low concentrations of antibiotics as compared to high antibiotic concentrations. For 66 antibiotic-resistant strains, no antimicrobial effect was observed on the bacterial Raman spectra. Full concordance with VITEK®2 data and broth dilution was obtained for the antibiotic-susceptible strains, 68 % and 98 %, respectively, for the resistant strains. Discriminative antimicrobial susceptibility testing (AST) profiles were obtained for all bacterial strains isolated from blood cultures, resulting in full concordance with the VITEK®2 data. It can be concluded that Raman spectroscopy is able to detect the antimicrobial susceptibility of bacterial species isolated from a positive blood culture bottle within 5 h. Although Raman spectroscopy is cheap and rapid, further optimization is required, to fulfill a great promise for future AST profiling technology development.

Lipopolysaccharide treatment induces genome-wide pre-mRNA splicing pattern changes in mouse bone marrow stromal stem cells

BACKGROUND

Lipopolysaccharide (LPS) is a gram-negative bacterial antigen that triggers a series of cellular responses. LPS pre-conditioning was previously shown to improve the therapeutic efficacy of bone marrow stromal cells/bone-marrow derived mesenchymal stem cells (BMSCs) for repairing ischemic, injured tissue.

RESULTS

In this study, we systematically evaluated the effects of LPS treatment on genome-wide splicing pattern changes in mouse BMSCs by comparing transcriptome sequencing data from control vs. LPS-treated samples, revealing 197 exons whose BMSC splicing patterns were altered by LPS. Functional analysis of these alternatively spliced genes demonstrated significant enrichment of phosphoproteins, zinc finger proteins, and proteins undergoing acetylation. Additional bioinformatics analysis strongly suggest that LPS-induced alternatively spliced exons could have major effects on protein functions by disrupting key protein functional domains, protein-protein interactions, and post-translational modifications.

CONCLUSION

Although it is still to be determined whether such proteome modifications improve BMSC therapeutic efficacy, our comprehensive splicing characterizations provide greater understanding of the intracellular mechanisms that underlie the therapeutic potential of BMSCs.

The systemic inflammatory response syndrome

The systemic inflammatory response syndrome (SIRS) describes the clinical presentation of patients with systemic activation of the inflammatory response from any underlying cause. SIRS is a common problem in acute medical and surgical practice and an important cause of morbidity and mortality. As a consequence of SIRS, patients may develop multiple organ dysfunction syndrome and acute respiratory distress syndrome (ARDS). Over the recent years our understanding of the inflammatory response in SIRS has increased, but as yet specific immunomodulatory therapies have not proved useful. The mainstay of treatment for patients with SIRS and ARDS remains a general supportive care. It is in this area that more encouraging advances are being made, particularly in the management of invasive ventilation and nutrition. In this review we summarize the definitions, epidemiology and pathophysiology of SIRS, ARDS and related conditions. We then give a description of the clinical consequences and treatment of SIRS and ARDS with an emphasis on current aspects of supportive care.

Peptide inhibition of p22phox and Rubicon interaction as a therapeutic strategy for septic shock

Sepsis is a clinical syndrome that complicates severe infection and is characterized by the systemic inflammatory response syndrome (SIRS), is a life threatening disease characterized by inflammation of the entire body. Upon microbial infection, p22phox-gp91phox NADPH oxidase (NOX) complexes produce reactive oxygen species (ROS) that are critical for the elimination of invading microbes. However, excess production of ROS represents a key element in the cascade of deleterious processes in sepsis. We have previously reported direct crosstalk between autophagy and phagocytosis machineries by demonstrating that the Rubicon protein interacts with p22phox upon microbial infection, facilitating phagosomal trafficking of the p22phox-gp91phox NOX complex to induce a ROS burst, inflammatory cytokine production, and thereby, potent anti-microbial activities. Here, we showed N8 peptide, an N-terminal 8-amino acid peptide derived from p22phox, was sufficient for Rubicon interaction and thus, capable of robustly blocking the Rubicon-p22phox interaction and profoundly suppressing ROS and inflammatory cytokine production. Consequently, treatment with the Tat-N8 peptide or a N8 peptide-mimetic small-molecule dramatically reduced the mortality associated with Cecal-Ligation-and-Puncture-induced polymicrobial sepsis in mice. This study demonstrates a new anti-sepsis therapeutic strategy by blocking the crosstalk between autophagy and phagocytosis innate immunity machineries, representing a potential paradigm shift for urgently needed therapeutic intervention against this life-threatening SIRS.

Community-onset sepsis and its public health burden: a systematic review

BACKGROUND

Sepsis is a life-threatening condition and major contributor to public health and economic burden in the industrialised world. The difficulties in accurate diagnosis lead to great variability in estimates of sepsis incidence. There has been even greater uncertainty regarding the incidence of and risk factors for community-onset sepsis (COS). We systematically reviewed the recent evidence on the incidence and risk factors of COS in high income countries (North America, Australasia, and North/Western Europe).

METHODS

Cohort and case-control studies were eligible for inclusion. Medline and Embase databases were searched from 2002 onwards. References of relevant publications were hand-searched. Two reviewers screened titles/abstracts and full-texts independently. One reviewer extracted data and appraised studies which were cross-checked by independent reviewers. Disagreements were resolved via consensus. Odds ratios (ORs) and 95 percent confidence intervals (95 % CIs) were ascertained by type of sepsis (non-severe, severe, and septic shock).

RESULTS

Ten cohort and 4 case-control studies were included. There was a wide variation in the incidence (# cases per 100,000 per year) of non-severe sepsis (range: 64-514), severe sepsis (range: 40-455), and septic shock (range: 9-31). Heterogeneity precluded statistical pooling. Two cohort and 4 case-control studies reported risk factors for sepsis. In one case-control and one cohort study, older age and diabetes were associated with increased risk of sepsis. The same case-control study showed an excess risk for sepsis in participants with clinical conditions (e.g., immunosuppression, lung disease, and peripheral artery disease). In one cohort study, higher risk of sepsis was associated with being a nursing home resident (OR = 2.60, 95 % CI: 1.20, 5.60) and in the other cohort study with being physically inactive (OR = 1.33, 95 % CI: 1.13, 1.56) and smoking tobacco (OR = 1.85, 95 % CI: 1.54, 2.22). The evidence on sex, ethnicity, statin use, and body mass index as risk factors was inconclusive.

CONCLUSIONS

The lack of a valid standard approach for defining sepsis makes it difficult to determine the true incidence of COS. Differences in case ascertainment contribute to the variation in incidence of COS. The evidence on COS is limited in terms of the number and quality of studies. This review highlights the urgent need for an accurate and standard method for identifying sepsis. Future studies need to improve the methodological shortcomings of previous research in terms of case definition, identification, and surveillance practice.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015023484.

Regulatory mechanisms underlying sepsis progression in patients with tumor necrosis factor-α genetic variations

The present study aimed to investigate the regulatory mechanisms underlying sepsis progression in patients with tumor necrosis factor (TNF)-α genetic variations. The GSE5760 expression profile data, which was downloaded from the Gene Expression Omnibus database, contained 30 wild-type (WT) and 28 mutation (MUT) samples. Differentially expressed genes (DEGs) between the two types of samples were identified using the Student's t-test, and the corresponding microRNAs (miRNAs) were screened using WebGestalt software. An integrated miRNA-DEG network was constructed using the Cytoscape software, based on the interactions between the DEGs, as identified using the Search Tool for the Retrieval of Interacting Genes/Proteins database, and the correlation between miRNAs and their target genes. Furthermore, Gene Ontology and pathway enrichment analyses were conducted for the DEGs using the Database for Annotation, Visualization and Integrated Discovery and the KEGG Orthology Based Annotation System, respectively. A total of 390 DEGS between the WT and MUT samples, along with 11 -associated miRNAs, were identified. The integrated miRNA-DEG network consisted of 38 DEGs and 11 miRNAs. Within this network, COPS2 was found to be associated with transcriptional functions, while FUS was found to be involved in mRNA metabolic processes. Other DEGs, including FBXW7 and CUL3, were enriched in the ubiquitin-mediated proteolysis pathway. In addition, miR-15 was predicted to target COPS2 and CUL3. The results of the present study suggested that COPS2, FUS, FBXW7 and CUL3 may be associated with sepsis in patients with TNF-α genetic variations. In the progression of sepsis, FBXW7 and CUL3 may participate in the ubiquitin-mediated proteolysis pathway, whereas COPS2 may regulate the phosphorylation and ubiquitination of the FUS protein. Furthermore, COPS2 and CUL3 may be novel targets of miR-15.

The cooperation between the autophagy machinery and the inflammasome to implement an appropriate innate immune response: do they regulate each other?

Autophagy is originally described as the main catabolic pathway responsible for maintaining intracellular nutritional homeostasis that involves the formation of a unique vacuole, the autophagosome, and the interaction with the endosome-lysosome pathways. This conserved machinery plays a key role in immune-protection against different invaders, including pathogenic bacteria, intracellular parasites, and some viruses like herpes simplex and hepatitis C virus. Importantly, autophagy is linked to a number of human diseases and disorders including neurodegenerative disease, Crohn's disease, type II diabetes, tumorigenesis, cardiomyopathy, and fatty liver disease. On the other hand, inflammasomes are multiprotein platforms stimulated upon several environmental conditions and microbial infection. Once assembled, the inflammasomes mediate the maturation of pro-inflammatory cytokines and promote phagosome-lysosome fusion to sustain an innate immune response. The intersections between autophagy and inflammasome have been observed in various diseases and microbial infections. This review highlights the molecular aspects involved in autophagy and inflammasome interactions during different medical conditions and microbial infections.

Antibiotic dose optimization in critically ill patients

The judicious use of existing antibiotics is essential for preserving their activity against infections. In the era of multi-drug resistance, this is of particular importance in clinical areas characterized by high antibiotic use, such as the ICU. Antibiotic dose optimization in critically ill patients requires sound knowledge not only of the altered physiology in serious infections - including severe sepsis, septic shock and ventilator-associated pneumonia - but also of the pathogen-drug exposure relationship (i.e. pharmacokinetic/pharmacodynamic index). An important consideration is the fact that extreme shifts in organ function, such as those seen in hyperdynamic patients or those with multiple organ dysfunction syndrome, can have an impact upon drug exposure, and constant vigilance is required when reviewing antibiotic dosing regimens in the critically ill. The use of continuous renal replacement therapy and extracorporeal membrane oxygenation remain important interventions in these patients; however, both of these treatments can have a profound effect on antibiotic exposure. We suggest placing emphasis on the use of therapeutic drug monitoring and dose individualization when optimizing therapy in these settings.

Community-onset sepsis and its public health burden: protocol of a systematic review

BACKGROUND

Sepsis is a life-threatening condition and major contributor of public health and economic burden in the industrialised world. The heterogeneity, absence of more specific definition, and difficulties in accurate diagnosis lead to great variability in the estimates of sepsis incidence. There has been uncertainty regarding the incidence and risk factors attributable to community-onset as opposed to hospital-acquired sepsis. Community-onset sepsis has distinct host characteristics, risk factors, pathogens, and prognosis. A systematic assessment of recent evidence is warranted in light of secular changes in epidemiology, pathogens, and the uncertainties around the incidence and risk factors of community-onset sepsis. This protocol describes a systematic review which aims to synthesise the recent empirical evidence on the incidence and risk factors of community-onset sepsis, severe sepsis, and septic shock in high-income countries.

METHODS/DESIGN

English-language publications of cohort and case-control studies reporting incidence and risk factors of community-onset sepsis will be eligible for inclusion. MEDLINE and Embase databases will be searched from 2002 and onwards. References of relevant publications will be hand-searched. Two reviewers will independently screen titles/abstracts and full texts as well as extract data and appraise the risk of bias of included studies. The data extractions and risk of bias assessments will be cross-checked. Any disagreements will be resolved via consensus. The data on incidence and risk factors of sepsis will be organised and synthesised in text, tables, and forest plots. The evidence will be pooled given sufficient data and degree of similarity across study populations, exposures, and outcomes. The heterogeneity will be assessed through visual inspection of forest plots, Chi-square-based p value, and I (2) statistic. The sources of heterogeneity will be explored via subgroup analysis.

DISCUSSION

Timeliness and accuracy of diagnosis of sepsis are both crucial aspects for improving the patient's outcome. The findings of this review will be discussed with a view to better inform future recommendations on improving public-facing campaigns, timely presentation, and diagnosis of sepsis in the community. The review will also discuss gaps in evidence and highlight future research and policy-making avenues for improving public health planning.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015023484.

Anti-inflammatory effects of benzenediamine derivate FC-98 on sepsis injury in mice via suppression of JNK, NF-κB and IRF3 signaling pathways

FC-98, a synthesized benzenediamine derivate, was reported to regulate Toll-like receptor 9-induced activation of dendritic cells in our previous study. In this study, we evaluated the anti-inflammatory properties of FC-98 both in macrophages and in septic mouse models. By using enzyme-linked immunosorbent assay and real-time quantitative PCR, we found that FC-98 (6.25, 25 and 100μM) dose-dependently attenuated lipopolysaccharide (LPS)-induced tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and monocyte chemoattractant protein (MCP-1) productions in RAW264.7 and primary mouse peritoneal macrophages. These inhibitory effects were not due to inducing cell cytotoxicity or altering LPS binding or TLR4 expression. Subsequently, western blot, immunofluorescence and luciferase reporter assays were used to investigate the underlying mechanisms of its anti-inflammatory activities. Results showed that FC-98 blocked activation of the c-Jun N-terminal kinase (JNK), nuclear factor-κB (NF-κB) and interferon regulatory factor 3 (IRF3) signaling pathways. In vivo, FC-98 (30 or 100mg/kg) was intraperitoneally administrated into LPS-induced or CLP-induced sepsis mice. It was observed to enhance the survival rate, inhibit pro-inflammatory mediator production, improve organ injuries and suppress bacterial propagation. In conclusion, FC-98 effectively inhibited macrophage inflammatory responses and ameliorated sepsis in mice through down-regulation of both MyD88 and TRIF-dependent pathways. These results suggest that FC-98 could be a promising therapeutic agent for inflammatory diseases.

Complement 5a receptor-mediated neutrophil dysfunction is associated with a poor outcome in sepsis

Complement 5a (C5a) has been implicated in the pathogenesis of sepsis by inducing the functional impairment of neutrophils; however, the utility of C5a receptors (C5aRs; C5aR and C5L2) as biomarkers for the management of sepsis is uncertain. This study investigated the dynamic expression of C5aR and C5L2 on neutrophils and their effects on neutrophil function. We found that sepsis patients displayed low expression levels of C5aR and C5L2 on neutrophils compared to healthy and systemic inflammatory response syndrome (SIRS) subjects, and this expression pattern was correlated with disease severity. Additionally, the expression levels of C5aR and C5L2 were associated with the survival of sepsis patients. In vitro, the addition of C5a significantly reduced C5aR and C5L2 expression levels and IL-8 production in neutrophils from sepsis patients. Those findings suggest that the reduced expression of C5aRs was associated with the functional impairment of neutrophils and a poor prognosis for sepsis patients. Overall, these findings may help establish C5aRs expression levels as early markers to predict the severity of sepsis.