Objective: The primary objective was to conduct a meta-analysis on published observational cohort data describing the association between acetyl-salicylic acid (aspirin) use prior to the onset of sepsis and mortality in hospitalized patients. Study Selection: Studies that reported mortality in patients on aspirin with sepsis with a comparison group of patients with sepsis not on prior aspirin therapy were included. Data Sources: Fifteen studies described hospital-based cohorts (n = 17,065), whereas one was a large insurance-based database (n = 683,421). Individual-level patient data were incorporated from all selected studies. Data Extraction: Propensity analyses with 1:1 propensity score matching at the study level were performed, using the most consistently available covariates judged to be associated with aspirin. Meta-analyses were performed to estimate the pooled average treatment effect of aspirin on sepsis-related mortality. Data Synthesis: Use of aspirin was associated with a 7% (95% CI, 2–12%; p = 0.005) reduction in the risk of death as shown by meta-analysis with considerable statistical heterogeneity (I 2 = 61.6%). Conclusions: These results are consistent with effects ranging from a 2% to 12% reduction in mortality risk in patients taking aspirin prior to sepsis onset. This association anticipates results of definitive studies of the use of low-dose aspirin as a strategy for reduction of deaths in patients with sepsis.
The pathophysiology of sepsis involves activation of acid sphingomyelinase (SMPD1) with subsequent generation of the bioactive mediator ceramide. We herein evaluate the hypothesis that the enzyme exerts biological effects in endothelial stress response. Plasma-secreted sphingomyelinase activity, ceramide generation and lipid raft formation were measured in human microcirculatory endothelial cells (HMEC-1) stimulated with serum obtained from sepsis patients. Clustering of receptors relevant for signal transduction was studied by immunostaining. The role of SMPD1 for macrodomain formation was tested by pharmacological inhibition. To confirm the involvement of the stress enzyme, direct inhibitors (amino bisphosphonates) and specific downregulation of the gene was tested with respect to ADAMTS13 expression and cytotoxicity. Plasma activity and amount of SMPD1 were increased in septic patients dependent on clinical severity. Increased breakdown of sphingomyelin to ceramide in HMECs was observed following stimulation with serum from sepsis patients in vitro. Hydrolysis of sphingomyelin, clustering of receptor complexes, such as the CD95L/Fas-receptor, as well as formation of ceramide enriched macrodomains were abrogated using functional inhibitors (desipramine and NB6). Strikingly, the stimulation of HMECs with serum obtained from sepsis patients or mixture of proinflammatory cytokines resulted in cytotoxicity and ADAMTS13 downregulation which was abrogated using desipramine, amino bisphosphonates and genetic inhibitors. SMPD1 is involved in the dysregulation of ceramide metabolism in endothelial cells leading to macrodomain formation, cytotoxicity and downregulation of ADAMTS13 expression. Functional inhibitors, such as desipramine, are capable of improving endothelial stress response during sepsis and might be considered as a pharmacological treatment strategy to obtain a favorable outcome.
Although various mouse inbred strains are widely used to investigate disease mechanisms and to establish new therapeutic strategies, sex-specific reference intervals for laboratory diagnostic analytes that are generated from large numbers of animals have been unavailable. In this retrospective study, we screened data from more than 12,000 mice phenotyped in the German Mouse Clinic from January 2006 through June 2014 and selected animals with the genetic background of C57BL/6J, C57BL/6N, or C3HeB/FeJ. In addition, we distinguished between the C57BL/6NTac substrain and C57BL/6N mice received from other vendors. The corresponding data sets of electrolytes (sodium, potassium, calcium, chloride, inorganic phosphate), lipids (cholesterol, triglyceride), and enzyme activities (ALT, AST, ALP, α-amylase) and urea, albumin, and total protein levels were analyzed. Significant effects of age and sex on these analytes were identified, and strain- or substrain- and sex-specific reference intervals for 90- to 135-d-old mice were calculated. In addition, we include an overview of the literature that reports clinical chemistry values for wild-type mice of different strains. Our results support researchers interpreting clinical chemistry values from various mouse mutants and corresponding wild-type controls based on the examined strains and substrains.
Background/Aims: Long-term kidney affections after sepsis are poorly understood. Animal models for investigating kidney damage in the late phase of disease progression are limited. The aim of this study was to investigate the impact of two antibiotic regimes on persistence of kidney injury after peritonitis. Methods: Kidney damage was investigated 65 days after polymicrobial peritoneal contamination and infection (PCI) sepsis induction in C57BL/6 mice. Short-term antibiotic therapy (STA, 4 days) was compared to long-term (LTA, 10 days) treatment using plasma creatinine, plasma and urine neutrophil gelatinase-associated lipocalin (NGAL), urine albumin/creatinine ratio and renal histology. Results: Sepsis resulted in mortality rates of 68.2% (STA) and 61.0% (LTA). Surviving STA animals showed the most pronounced kidney damage indicated by significantly elevated levels of creatinine and acute tubular damage (ATD), whereas NGAL was significantly increased in LTA survivors only. A creatinine level above 0.3 mg/dl was used to define kidney injury, found in 21.4% of STA animals and 7.8% of LTA animals. While animals with kidney injury demonstrated significantly higher ATD scores and persistent tubular damage, no significant differences were found for plasma or urine NGAL levels or urine albumin/creatinine ratios. Conclusion: Prolonged antibiotic treatment reduced the rate of ongoing peritonitis-induced kidney injury in a C57BL/6 mouse model. Plasma or urine NGAL levels were not able to identify animals with or without persistent kidney injury. The kidney injury after the PCI mouse model represents prototypic clinical findings and should be used for further studies investigating disease mechanisms.
Acute kidney injury (AKI) during sepsis is common and underestimated. Plasma neutrophil gelatinase-associated lipocalin (plasma-NGAL) is discussed as new biomarker for AKI diagnosis, but during inflammation its function and diagnostic impact remain unclear. The association between plasma-NGAL and inflammatory markers in septic patients, but also in healthy controls and patients with chronic inflammation before and after either maximum exercise test or treatment with an anti-TNF therapy were investigated. In-vitro blood stimulations with IL-6, lipopolysaccharide, NGAL or its combinations were performed to investigate cause-effect-relationship. Plasma-NGAL levels were stronger associated with inflammation markers including IL-6 (Sepsis: r = 0.785 P < 0.001; chronic inflammation after anti-TNF: r = 0.558 P < 0.001), IL-8 (Sepsis: r = 0.714 P<0.004; healthy controls after exercise r = 0.786 P < 0.028; chronic inflammation before anti-TNF: r = 0.429 P < 0.041) and IL-10 (healthy controls before exercise: r = 0.791 P < 0.028) than with kidney injury or function. Correlation to kidney injury or function was found only in septic patients (for creatinine: r = 0.906 P < 0.001; for eGFR: r = -0.686 P = 0.005) and in patients with rheumatic disease after anti-TNF therapy (for creatinine: r = 0.466 P < 0.025). In stimulation assays with IL-6 and lipopolysaccharide plasma-NGAL was increased. Co-stimulation of lipopolysaccharide with plasma-NGAL decreased cellular injury (P < 0.05) and in trend IL-10 levels (P = 0.057). Septic mice demonstrated a significantly improved survival rate after NGAL treatment (P < 0.01). Plasma-NGAL seams to be strongly involved in inflammation. For clinical relevance, it might not only be useful for AKI detection during severe inflammation - indeed it has to be interpreted carefully within this setting - but additionally might offer therapeutic potential.
PURPOSE:Acute kidney injury during systemic infections is common; however, renal outcome is poorly investigated. The increase of multiresistant pathogens leads to the use of potential nephrotoxic antibiotics as vancomycin. We investigated the impact of vancomycin and renal replacement therapy (RRT) for renal recovery during sepsis.MATERIALS AND METHODS:This is a retrospective data analysis of 1159 patients with severe sepsis or septic shock. Logistic regression models were performed.RESULTS:In total, 390 (33.6%) patients required RRT during intensive care unit (ICU) stay; 233 (20.1%), at discharge. Admission estimated glomerular filtration rate (eGFR) predicted the need of RRT during stay (odds ratio [OR] 0.969 [0.959-0.979] per increase of 1 mL/min, P<.001) and the prolonged need of RRT at ICU discharge (OR 0.979 [0.967-0.990], P<.001). Survivors without any RRT showed an improvement of eGFR at discharge, whereas patients after RRT did not (7.1 vs 0.8 mL/[min 1.73 m2], P<.001). The use (OR 1.648 [1.067-2.546], P<.05) and duration of vancomycin treatment (OR 1.043 [1.004-1.084] per each additional treatment day, P<.05) were predictors for ongoing RRT at discharge.CONCLUSIONS:Estimated GFR at ICU admission predicts renal outcome, whereas the use of vancomycin increases the probability of a prolonged need for RRT at discharge from ICU. The use of alternative antibiotics for certain patients, indicated by eGFR at admission, might be considered.
INTRODUCTION:Circulating histones have been identified as mediators of damage in animal models of sepsis and in patients with trauma-associated lung injury. Despite existing controversies on actual histone concentrations, clinical implications and mechanism of action in various disease conditions, histone levels in human sepsis, association with disease progression and mediated effects on endothelial and immune cells remain unreported. This study aimed to determine histone levels and its clinical implication in septic patients and to elucidate histone-mediated effects ex-vivo.METHODS:Histone levels, endogenous activated protein C (APC) levels and clinical data from two independent cohorts of septic patients were obtained. Histone levels were compared with various control groups including healthy individuals, intensive care unit (ICU) patients without sepsis, ICU patients with multiple organ failure and patients with minor or multiple trauma, all without infection. Endothelial and monocytic cells were stimulated with histones. Cellular integrity and sepsis prototypical cytokines were evaluated. The mechanism of action of histones via Toll-like receptor 4 (TLR4) was evaluated using a function blocking antibody. Histone degradation in plasma was studied by immunoblotting.RESULTS:Histone H4 levels were significantly elevated in patients with sepsis (cohort I; n = 15 and cohort II; n = 19) versus ICU controls (n = 12), patients with multiple organ failure (n = 12) or minor trauma (n = 7), associated with need for renal replacement therapy and decrease in platelet count during disease progression, and remarkably were significantly associated with increased mortality rates in septic patients (ICU-, 28 day- and 90 day mortality rates). There was an inverse correlation between plasma histones and endogenous APC levels. Histone stimulation induced the release of sepsis prototypic cytokines and decreased cell integrity indicated by a significant increase of lactate dehydrogenase (LDH) and propidium iodide (PI) staining. Blocking of TLR4 decreased cellular cytotoxicity on endothelial cells. The calculated half-life of histones in spiked plasma was 4.6 minutes.CONCLUSIONS:Histone levels in septic patients are significantly increased and might mediate disease aggravation by cellular injury and inflammation via TLR4 signaling, which potentially results in multiple organ failure and fatal outcome.
We agree with Bara and Joffe that there is a need for improvement of reporting quality in animal research (AR) [1]. Presenting details on both methods used and potential cofounders during AR is not only important to reproduce results, and to ensure animal welfare (AW) and public support, it is a duty when animals are compromised, stressed or sacrificed to understand diseases or to identify treatment targets. The article addresses important issues, unfortunately without a solution and ignoring personal responsibility. As mentioned, the word count within manuscripts is strictly limited. In Germany and most European countries, the approval procedure for AR includes applications (>6,000 words) covering all analysed readouts: anaesthesia, pain control, euthanasia methods, termination criteria, statistical planning, funding, discussion of reduction, refinement and replacement, and a systematic review. Nevertheless, how should these long method descriptions be included in manuscripts of 3,500 words? Really what are required are special conferences and articles focusing on methods in AR, a uniform summarising data sheet as supplementary material, and the presentation of the registration number given by the AW committee including a recheck by the committees to ensure that AW was considered. Finally, there is a need for commitment among scientists to standardise experiments to allow collaborative exchange of data, body fluids and tissues to privilege synergetic benefits; to improve the informative value of an approach by stratification of animals [2]; and to also present negative results to avoid double testing. These changes will lead to increased quality in reporting, realisation of reduction, refinement and replacement, and public perception.
Measuring (1->3)-beta-D-glucan has recently been advocated for detection of invasive candidiasis. Our data indicate that the rate of false positive results is potentially high in some patient collectives of risk, e.g. after cardiac artery bypass grafting.
Objectives:High physical activity levels are associated with wide-ranging health benefits, disease prevention, and longevity. In the present study, we examined the impact of regular physical exercise on the severity of organ injury and survival probability, as well as characteristics of the systemic immune and metabolic response during severe polymicrobial sepsis. Design:Animal study. Setting:University laboratory. Subjects:Male C57BL/6N mice. Interventions:Mice were trained for 6 weeks by treadmill and voluntary wheel running or housed normally. Polymicrobial sepsis in mice was induced by injection of fecal slurry. Subsequently, mice were randomized into the following groups: healthy controls, 6 hours postsepsis, and 24 hours postsepsis. Measurements and Main Results:Blood and organ samples were collected and investigated by measuring clinical chemistry variables, cytokines, plasma metabolites, and bacterial clearance. Organ morphology and damage were characterized by histological staining. Physical exercise improved survival and the ability of bacterial clearance in blood and organs. The release of pro- and anti-inflammatory cytokines, including interleukin-6 and interleukin-10, was diminished in trained compared to untrained mice during sepsis. The sepsis-associated acute kidney tubular damage was less pronounced in pretrained animals. By metabolic profiling and regression analysis, we detected lysophosphatidylcholine 14:0, tryptophan, as well as pimelylcarnitine linked with levels of neutrophil gelatinase-associated lipocalin representing acute tubular injury (corrected R2 = 0.910; p < 0.001). We identified plasma lysophosphatidylcholine 16:0, lysophosphatidylcholine 17:0, and lysophosphatidylcholine 18:0 as significant metabolites discriminating between trained and untrained mice during sepsis. Conclusions:Regular physical exercise reduces sepsis-associated acute kidney injury and death. As a specific mechanism of exercise-induced adaptation, we identified various lysophosphatidylcholines that might function as surrogate for improved outcome in sepsis.
Analyzing medical records of 979 patients with severe sepsis or septic shock provided some evidence that the use of low-dose aspirin or non-steroidal anti-inflammatory drugs (NSAIDs) was associated with decreased hospital mortality. However, the benefit was abolished when aspirin and NSAIDs were given together.
Severe systemic infections are one of the leading causes of death in patients with end-stage renal disease and are often associated with hospitalization. Since bacteria can be identified in used hemofilters in an ICU setting, it was investigated whether this method might be useful in patients undergoing regular intermittent hemodialysis. By analyzing used hemodialyzers in (n = 13) patients, we identified systemic bacteremia in two patients (15.4%) while corresponding blood cultures were negative. In two further patients, positive microbiological findings from hemodialyzers appeared to be of unclear clinical relevance. Cultures from hemodialyzers might be an add-on approach for the identification of bacteria in the blood stream of patients undergoing regular intermittent hemodialysis.
The impact of cytokine storm on plasma neutrophil gelatinase-associated lipocalin (NGAL) levels during polymicrobial sepsis is unknown. We demonstrate the advantage of plasma NGAL as marker for acute kidney injury (AKI) during septic cytokine storm and an early correlation of tumor necrosis factor alpha (TNFa) with NGAL during septic AKI.
PURPOSE:The aim of the study was to examine the onset and frequency of physiotherapeutic interventions (PTI) and their potential effects on the intensive care unit (ICU) mortality rate in patients with severe sepsis or septic shock.MATERIAL AND METHODS:Retrospective data analysis. Univariate and multivariate Cox proportional-hazards regression analyses were performed.RESULTS:About 6.2% of all patients (n = 999, length of ICU stay 12 days, averaged SOFA score 14) developed sepsis within three years. Of these, 77% received at least once PTI. The relative number of PTI (RNPTI index, individually calculated by the number of PTI/length of stay) in patients with sepsis was 42%. The first physiotherapeutic treatment was five days after ICU admission. Cox regression multivariate analysis adjusted by disease severity scores, sedation state and other clinical variables found RNPTI index as significant risk factor for the ICU mortality rate (hazard ratio, 0.982; 95% confidence interval, 0.974-0.990; P < .001).CONCLUSIONS:Physiotherapists routinely assess and treat patients with sepsis. The frequency of PTI was associated with an improved outcome. Prospective studies are necessary to confirm the potential favorable impact.
Hintergrund: Das Bild kritisch kranker Patienten mit schwerer Sepsis oder septischen Schock auf Intensivstationen (ITS) wird von Immobilität und Bettruhe bestimmt. Eine wesentliche Folge ist die zunehmende physische Dekonditionierung der Patienten während ihres ITS-Aufenthaltes, die den klinischen aber auch ambulanten Krankheitsverlauf erheblich beeinflusst. Um dieser Entwicklung entgegen zu wirken, stellt die frühe physiotherapeutische Intervention (PTI) eine Therapiestrategie in der Behandlung dieser Patienten dar. Ziel: In zwei unabhängigen Studien sollte erfasst werden, inwieweit die frühe PTI in das Behandlungskonzept bei septischen Patienten am Universitätsklinikum in Jena implementiert ist und ob die Häufigkeit der PTI den akuten Krankheitsverlauf positiv beeinflussen kann (Studie I, retrospektiv). Darüber hinaus wurde erhoben, welche physiotherapeutischen Maßnahmen angewendet und welche Therapieziele dabei verfolgt werden (Studie II, prospektiv). Ergebnisse: Retrospektiv wurden 16.041 Patienten analysiert, wobei 999 die Kriterien für schwere Sepsis oder septischen Schock erfüllten. Die Mortalitätsrate septischer Patienten betrug 30,8% und die mittlere ITS-Liegedauer 12 Tage. Insgesamt wurden 9.476 PTI angewendet, die auf 77% der Patienten entfielen. Die PTI-Rate (PTI/Liegedauer) bei Patienten mit schwerer Sepsis oder septischen Schock betrug 42%. Regressionsanalysen zeigten auf, dass die PTI-Rate ein starker Prädiktor für die ITS-Mortalität ist. Als wichtigste Therapieziele konnten prospektiv die Prophylaxe/Therapie von Kontrakturen und Pneumonien erhoben werden, wobei passive Mobilisierungsmaßnahmen, die Atemtherapie und Lagerungstherapie am häufigsten angewendet wurden. Schlussfolgerung: Erstmalig wurde die Implementierung von physiotherapeutischen Maßnahmen und deren mögliche Auswirkungen bei Patienten mit Sepsis analysiert. Hieran sollten sich weitere Studien anschließen.
Sepsis and its sequelae of multiple organ failure is one of the leading causes of death in the industrial countries. Several studies have shown that patients who are treated with low-dose acetyl salicylic acid (ASA) for secondary prevention of atherothrombosis may have a lower risk to develop organ failure in the case of critical illness. The benefit of ASA is probably due to an inhibition of platelet activation as well as an increase in the formation of anti-inflammatory lipoxin A4. On the other hand, the effect of ASA could be - at least partially - an indirect one, caused by atherosclerotic vascular diseases as the cause of ASA treatment. Atherosclerosis is considered as a moderate systemic inflammation and we hypothesise that this chronic condition could have an impact on the outcome in sepsis. To get more information on the benefit of ASA in critically ill patients and on possible interference with atherosclerotic vascular diseases, we analysed the medical records of 886 septic patients who were admitted to the surgical intensive care unit (ICU) of a university hospital. Logistic regression analysis indicated that patients who were treated during the ICU stay with ASA (100 mg/d) had a significantly lower mortality. Odds ratios (ORs; with 95% confidential intervals) of 0.56 (0.37-0.84) and 0.57 (0.39-0.83) were calculated for ICU and hospital mortality, respectively. In contrast, statin treatment did not have significant effect on mortality. Diagnosis of atherosclerotic vascular diseases according to ICD classification did not influence ICU mortality but lowered hospital mortality (OR = 0.71 (0.52-0.99)). Subgroup analysis provided preliminary evidence that clopidogrel when given as only anti-platelet drug may have a similar benefit as ASA, but the combination of ASA and clopidogrel failed to improve the outcome. The time course of plasma fibrinogen and procalcitonin levels indicate that ASA seems to reduce the activation of haemostasis and increase the resolution of inflammation. It is concluded that prospective interventional studies should be done to test the use of ASA as novel therapeutic approach in critically ill patients.
The use of hydroxyethylstarch (HES) is a controversial issue due to increasing evidence that HES accumulates in plasma and various tissues and therefore leads to unfavourable outcome in critically ill patients [1,2]. No simple methods are available for monitoring HES plasma levels; present technologies to measure HES are based on gas chromatography-mass spectrometry, which are time-consuming and need advanced equipment [3]. Here, we applied Lugol's iodine solution (LUGOL; Sigma-Aldrich, Steinheim, Germany) to determinate HES concentrations in plasma and compare the results with those obtained by high-performance liquid chromatography (HPLC). The study was approved by the institutional ethical committee (Friedrich-Schiller-University, Jena) as well as by the animal welfare committee (Thuringer Landesamt fur Lebensmittelsicherheit und Verbraucherschutz, Germany). Blood samples from healthy volunteers were diluted with balanced 6% HES 130/0.4 (Fresenius Kabi, Bad Homburg, Germany) to get concentrations up to 30 mg/ml. Samples were centrifuged (10 minutes, 4,700 × g, 4°C), and plasma aliquots were mixed with 10% trichloroacetic acid and re-centrifuged (5 minutes, 4,700 × g, 4°C). The supernatant was mixed (4:1) with LUGOL and optical density was measured at 530 nm. For in vivo experiments, 5 ml or 10 ml of 6% HES 130/0.4 was infused into wistar rats over 1 hour via a central venous catheter. Blood samples were obtained prior and up to 24 hours after infusion. Plasma samples were prepared as described. For HPLC analysis, plasma samples were diluted 1:10 with water, then mixed with 60% perchloric acid, heated at 90°C for 60 minutes, diluted again (1:50) and subjected to HPLC [4]. For correlation analysis the Pearson correlation coefficient was calculated. Using the LUGOL method, we found a linear correlation (r2 > 0.99) between calculated and measured plasma HES concentrations after serial dilutions of HES 130/0.4 in human whole blood (Figure (Figure1a).1a). At a concentration of 6 mg/ml the half life of HES 130/0.4 was estimated to be 1.8 hours (Figure (Figure1b).1b). In rats, plasma levels of 2.9 mg/ml and 4.6 mg/ml were measured immediately after infusion of 5 or 10 ml HES 130/0.4. Two hours after infusion the measured levels were only 10% of the initial levels (Figure (Figure2).2). Comparing the plasma concentrations measured by LUGOL and HPLC revealed a correlation coefficient of r2 > 0.90 (P < 0.001). Figure 1 Quantification of HES by Lugol's iodine solution. (a) Measurement of HES concentration using LUGOL's iodine solution in samples of human whole blood incubated with different HES 130/0.4 concentrations. (b) Time course of HES concentration in human whole ... Figure 2 Time course of HES plasma levels after infusion of 5 or 10 ml HES 130/0.4 solution over 1 hour. Significance was tested using ANOVA (*P < 0.05). The new method described here allows the rapid and simple detection of HES in plasma samples. LUGOL is known to stain polysaccharides, including amylose, amylopectin and glycogen. Amylose and amylopectin, due to their herbal origin, should not be found in blood. However, glycogen might interfere with the measurements, but it is present in only negligible amounts in plasma [5]. Measurement of HES plasma levels in patients could help to gain new insights into HES degradation and plasma accumulation after infusion.
ABSTRACT Intracellular persistence of Chlamydia trachomatis has been implicated in the development of chronic infection that can result in pelvic inflammatory disease and tubal sterility. By inhibition of host cell apoptosis, chlamydiae have evolved a strategy to maintain the intracellular environment for replication and persistence. Both antiapoptotic host cell-derived factors and the chlamydial protease-like activity factor (CPAF) are involved in Chlamydia-mediated apoptosis resistance. Here, we show that in HeLa cells infected with gamma interferon (IFN-γ)-induced persistent C. trachomatis serovar D, the expression of CPAF is downregulated, and proapoptotic protease substrates are not cleaved. Persistent infection protected HeLa cells from apoptosis when they were exposed to staurosporine. Small-interfering RNA-mediated inhibition of myeloid cell leukemia 1 (Mcl-1) protein upregulation sensitized persistently infected cells for apoptosis. The inhibitor of apoptosis protein 2 (IAP-2) seems not to be relevant in this context because IAP-2 protein was not induced in response to IFN-γ treatment. Although apoptosis was inhibited, persistent infection caused cell membrane disintegration, as measured by the increased release of cytokeratin 18 from HeLa cells. Moreover, persistently infected cells released significantly increased amounts of high mobility group box 1 (HMGB1) protein which represents a proinflammatory damage-associated pattern molecule. The data of this study suggest that cells infected with persistent C. trachomatis are protected from apoptosis independently of CPAF but may promote chronic inflammation through HMGB1 release.