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Purpose: Timely and accurate data on the epidemiology of sepsis are essential to inform policy decisions and research priorities. We aimed to investigate the validity of inpatient administrative health data (IAHD) for surveillance and quality assurance of sepsis care., Methods: We conducted a retrospective validation study in a disproportional stratified random sample of 10,334 inpatient cases of age ≥ 15 years treated in 2015-2017 in ten German hospitals. The accuracy of coding of sepsis and risk factors for mortality in IAHD was assessed compared to reference standard diagnoses obtained by a chart review. Hospital-level risk-adjusted mortality of sepsis as calculated from IAHD information was compared to mortality calculated from chart review information., Results: ICD-coding of sepsis in IAHD showed high positive predictive value (76.9-85.7% depending on sepsis definition), but low sensitivity (26.8-38%), which led to an underestimation of sepsis incidence (1.4% vs. 3.3% for severe sepsis-1). Not naming sepsis in the chart was strongly associated with under-coding of sepsis. The frequency of correctly naming sepsis and ICD-coding of sepsis varied strongly between hospitals (range of sensitivity of naming: 29-71.7%, of ICD-diagnosis: 10.7-58.5%). Risk-adjusted mortality of sepsis per hospital calculated from coding in IAHD showed no substantial correlation to reference standard risk-adjusted mortality (r = 0.09)., Conclusion: Due to the under-coding of sepsis in IAHD, previous epidemiological studies underestimated the burden of sepsis in Germany. There is a large variability between hospitals in accuracy of diagnosing and coding of sepsis. Therefore, IAHD alone is not suited to assess quality of sepsis care., (© 2023. The Author(s).)

Introduction: Sepsis is a major cause of preventable deaths in hospitals. This study aims to investigate if sepsis incidence and quality of care can be assessed using inpatient administrative health data (IAHD)., Methods and Analysis: Design: Retrospective observational validation study using routine data to assess the diagnostic accuracy of sepsis coding in IAHD regarding sepsis diagnosis based on medical record review., Procedure: A stratified sample of 10 000 patients with an age ≥15 years treated in between 2015 and 2017 in 10 German hospitals is investigated. All available information of medical records is screened by trained physicians to identify true sepsis cases ('gold standard') both according to current ('sepsis-1') definitions and new ('sepsis-3') definitions. Data from medical records are linked to IAHD on patient level using a pseudonym., Analyses: Proportions of cases with sepsis according to sepsis-1 and sepsis-3 definitions are calculated and compared with estimates from coding of sepsis in IAHD. Predictive accuracy (sensitivity, specificity) of different coding abstraction strategies regarding the gold standard is estimated. Predictive accuracy of mortality risk factors obtained from IAHD regarding the respective risk factors obtained from medical records is calculated. An IAHD-based risk model for hospital mortality is compared with a record-based risk model regarding model-fit and predicted risk of death. Analyses adjust for sampling weights. The obtained estimates of sensitivity and specificity for sepsis coding in IAHD are used to estimate adjusted incidence proportions of sepsis based on German national IAHD., Ethics and Dissemination: The study has been approved by the ethics commission of the Jena University Hospital (No. 2018-1065-Daten). The results of the study will be discussed in an expert panel to write a memorandum on improving the utility of IAHD for epidemiological surveillance and quality management of sepsis care., Trial Registration Number: DRKS00017775; Pre-results., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Rationale: The liver is a central organ not only for metabolism but also immune function. Life-threatening infections of both bacterial and fungal origin can affect liver function but it is yet unknown whether molecular changes differ depending on the pathogen. We aimed to determine whether the hepatic host response to bacterial and fungal infections differs in terms of hepatic metabolism and liver function. Methods: We compared murine models of infection, including bacterial peritoneal contamination and infection (PCI), intraperitoneal and systemic C. albicans infection, at 6 and 24 h post-infection, to sham controls. The molecular hepatic host response was investigated by the detection of regulatory modules based on large-scale protein-protein interaction networks and expression data. Topological analysis of these regulatory modules was used to reveal infection-specific biological processes and molecular mechanisms. Intravital microscopy and immunofluorescence microscopy were used to further analyze specific aspects of pathophysiology such as cholestasis. Results: Down-regulation of lipid catabolism and bile acid synthesis was observed after 6 h in all infection groups. Alterations in lipid catabolism were characterized by accumulation of long chain acylcarnitines and defective beta-oxidation, which affected metabolism by 6 h. While PCI led to an accumulation of unconjugated bile acids (BA), C. albicans infection caused accumulation of conjugated BA independent of the route of infection. Hepatic dye clearance and transporter expression revealed reduced hepatic uptake in fungal infections vs. defects in secretion following polybacterial infection. Conclusion: Molecular phenotypes of lipid accumulation and cholestasis allow differentiation between pathogens as well as routes of infection at early stages in mice. Targeted metabolomics could be a useful tool for the profiling of infected/septic patients and the type of pathogen, with subsequent customization and targeting of therapy., Competing Interests: Competing Interests: The authors have declared that no competing interest exists.

Metamizole is primarily used for severe perioperative pain, acute injury and colic, and cancer pain. For other acute/chronic forms of pain and high fever, it should only be used if unresponsive to other agents. Metamizole should not be used for middle and low pain. Oral application should be preferred. A contraindication for metamizole is leukopenia. Clinical signs for agranulocytosis are fever, tonsillitis and aphthous stomatitis., Competing Interests: Winfried Meißner erhielt Forschungsförderung von Grünenthal und Pfizer, Beratungshonorare von Sanofi, Grünenthal, AcelRx Pharmaceuticals, Menarini und BioQ Pharma sowie Honorare für Vorträge von Grünenthal, Mundipharma und Menarini., (Georg Thieme Verlag KG Stuttgart · New York.)

The molecular mechanisms of maladaptive response in liver tissue with respect to the acute and post-acute phase of sepsis are not yet fully understood. Long-term sepsis survivors might develop hepatocellular/hepatobiliary injury and fibrosis. Here, we demonstrate that acid sphingomyelinase, an important regulator of hepatocyte apoptosis and hepatic stellate cell (HSC) activation, is linked to the promotion of liver dysfunction in the acute phase of sepsis as well as to fibrogenesis in the long-term. In both phases, we observed a beneficial effect of partial genetic sphingomyelinase deficiency in heterozygous animals (smpd1 +/- ) on oxidative stress levels, hepatobiliary function, macrophage infiltration and on HSC activation. Strikingly, similar to heterozygote expression of SMPD1, either preventative (p-smpd1 +/+ ) or therapeutic (t-smpd1 +/+ ) pharmacological treatment strategies with desipramine - a functional inhibitor of acid sphingomyelinase (FIASMA) - significantly improved liver function and survival. The inhibition of sphingomyelinase exhibited a protective effect on liver function in the acute-phase, and the reduction of HSC activation diminished development of sepsis-associated liver fibrosis in the post-acute phase of sepsis. In summary, targeting sphingomyelinase with FDA-approved drugs is a novel promising strategy to overcome sepsis-induced liver dysfunction.

The breakdown of the blood-brain barrier (BBB) is a key event in the development of sepsis-induced brain damage. BBB opening allows blood-born immune cells to enter the CNS to provoke a neuroinflammatory response. Abnormal expression and activation of matrix metalloproteinases (MMP) was shown to contribute to BBB opening. Using different mouse genotypes in a model of LPS-induced systemic inflammation, our present report reveals phosphoinositide 3-kinase γ (PI3Kγ) as a mediator of BBB deterioration and concomitant generation of MMP by microglia. Unexpectedly, microglia expressing lipid kinase-deficient mutant PI3Kγ exhibited similar MMP regulation as wild-type cells. Our data suggest kinase-independent control of cAMP phosphodiesterase activity by PI3Kγ as a crucial mediator of microglial cell activation, MMP expression and subsequent BBB deterioration. The results identify the suppressive effect of PI3Kγ on cAMP as a critical mediator of immune cell functions.

Liver failure and hepatic dysfunction represent diagnostic and therapeutic challenges for the intensivist. Besides acute liver failure, hypoxic hepatitis, sepsis and (secondary) sclerosing cholangitis may lead to massive liver dysfunction with subsequent multiorgan dysfunction syndrome that limits survival. Among classical laboratory parameters (so-called static liver parameters) liver function tests may help with the diagnosis to allow early treatment or prevention of liver dysfunction. The aim of this article is to present the current aspects of liver function monitoring and to provide guidelines to the intensivist for diagnosing liver dysfunction in the intensive care setting.

Intravital fluorescence microscopy (IVM) is a predestined tool for investigating the fate of leukocytes during the process of leukocyte recruitment. In the present study, the commonly used dye for this purpose, rhodamine 6G, and carboxyfluorescein diacetate succinimidyl ester (CFDA-SE) were compared for leukocytes labelling with respect to suitability for IVM studies. Their potential in labelling different leukocytes subpopulations as well as their fluorescence intensities were assessed by flow cytometry revealing distinct differences between both dyes. These differences had a profound impact on their application for in vivo imaging of leukocyte-endothelium interactions. In summary, CFDA-SE revealed superior in labelling leukocytes for in vivo microscopy with respect to image quality. In addition, we could show the efficiency of CFDA-SE also under disease condition in an animal model of sepsis., (Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Introduction: Hepatobiliary elimination of endo- and xenobiotics is affected by different variables including hepatic perfusion, hepatocellular energy state and functional integrity of transporter proteins, all of which are altered during sepsis. A particular impairment of hepatocellular transport at the canalicular pole resulting in an accumulation of potentially hepatotoxic compounds would have major implications for critical care pharmacology and diagnostics., Methods: Hepatic transcellular transport, that is, uptake and hepatobiliary excretion, was studied in a rodent model of severe polymicrobial sepsis by two different biophotonic techniques to obtain insights into the handling of potentially toxic endo- and xenobiotics in sepsis. Direct and indirect in vivo imaging of the liver was performed by intravital multifluorescence microscopy and non-invasive whole-body near-infrared (NIRF) imaging after administration of two different, primarily hepatobiliary excreted xenobiotics, the organic anionic dyes indocyanine green (ICG) and DY635. Subsequent quantitative data analysis enabled assessment of hepatic uptake and fate of these model substrates under conditions of sepsis., Results: Fifteen hours after sepsis induction, animals displayed clinical and laboratory signs of multiple organ dysfunction, including moderate liver injury, cholestasis and an impairment of sinusoidal perfusion. With respect to hepatocellular transport of both dyes, excretion into bile was significantly delayed for both dyes and resulted in net accumulation of potentially cytotoxic xenobiotics in the liver parenchyma (for example, specific dye fluorescence in liver at 30 minutes in sham versus sepsis: ICG: 75% versus 89%; DY635 20% versus 40% of maximum fluorescence; P<0.05). Transcutaneous assessment of ICG fluorescence by whole body NIRF imaging revealed a significant increase of ICG fluorescence from the 30th minute on in the bowel region of the abdomen in sham but not in septic animals, confirming a sepsis-associated failure of canalicular excretion., Conclusions: Hepatocytes accumulate organic anions under conditions of sepsis-associated organ dysfunction. These results have potential implications for monitoring liver function, critical care pharmacology and the understanding of drug-induced liver injury in the critically ill.

Background: Many of the concepts describing molecular mechanisms of sepsis-induced liver failure are derived from endotoxin models. However, the biological significance of such models is questionable as the complexity of clinical sepsis and associated organ failure is only partially replicated., Aims: Comparison of cytokine response, leucocyte recruitment, oxidative stress and markers of hepatic organ dysfunction in rat models of endotoxaemia or peritoneal contamination and infection (PCI)., Methods: Endotoxemia and polymicrobial sepsis were induced in rats by intraperitoneal injection of lipopolysaccharide (LPS) or stool suspension, respectively., Results: Both insults produced clinical and laboratory signs of multiple organ dysfunction, including hepatic excretory dysfunction. However, TNF alpha, oxidative stress responses and the degree of cell death were significantly higher in endotoxaemia compared to PCI (e.g. serum TNF levels (pg/ml) at 1.5 h post-insult: sham 5 ± 1.4, LPS 1 mg/kg bw 2176.92 ± 373.78, sepsis below detection limit; P P < 0.05). Cholestasis was significantly more pronounced in polymicrobial sepsis whereas serum bilirubin in endotoxaemic animals did not differ from sham-operated controls (plasma levels of bilirubin (μmol/L) at 15 h after the insult: sham 7.1 ± 0.6, LPS 30 mg/kg 9.1 ± 0.6, sepsis 15.2 ± 1.3)., Conclusions: Polymicrobial sepsis produces profound hepatocellular dysfunction in the absence of traditional cytokine-mediated mechanisms of cellular injury. This questions the central role of cytokines and the ensuing oxidative stress as key molecular events in mediating liver dysfunction., (© 2012 John Wiley & Sons A/S.)

Plasma secretion of acid sphingomyelinase is a hallmark of cellular stress response resulting in the formation of membrane embedded ceramide-enriched lipid rafts and the reorganization of receptor complexes. Consistently, decompartmentalization of ceramide formation from inert sphingomyelin has been associated with signaling events and regulation of the cellular phenotype. Herein, we addressed the question of whether the secretion of acid sphingomyelinase is involved in host response during sepsis. We found an exaggerated clinical course in mice genetically deficient in acid sphingomyelinase characterized by an increased bacterial burden, an increased phagocytotic activity, and a more pronounced cytokine storm. Moreover, on a functional level, leukocyte-endothelial interaction was found diminished in sphingomyelinase-deficient animals corresponding to a distinct leukocytes' phenotype with respect to rolling and sticking as well as expression of cellular surface proteins. We conclude that hydrolysis of membrane-embedded sphingomyelin, triggered by circulating sphingomyelinase, plays a pivotal role in the first line of defense against invading microorganisms. This function might be essential during the early phase of infection leading to an adaptive response of remote cells and tissues.

Experimental models, mimicking physiology, and molecular dynamics of diseases in human, harbor the possibility to study the effect of interventions and transfer results from bench to bedside. Recent advances in high-throughput technologies, standardized protocols, and integration of knowledge from databases yielded rising consistency and usability of results for inter-species comparisons. Here, we explored similarities and dissimilarities in gene expression from blood samples of a murine sepsis model (peritoneal contamination and infection, PCI) and patients from the pediatric intensive care unit (PICU) measured by microarrays. Applying a consistent pre-processing and analysis workflow, differentially expressed genes (DEG) from PCI and PICU data significantly overlapped. A major fraction of DEG was commonly expressed and mapped to adaptive and innate immune response related pathways, whereas the minor fraction, including the chemokine (C-C motif) ligand 4, exhibited constant inter-species disparities. Reproducibility of transcriptomic observations was validated experimentally in PCI. These data underline, that inter-species comparison can obtain commonly expressed transcriptomic features despite missing homologs and different protocols. Our findings point toward a high suitability of an animal sepsis model and further experimental efforts in order to transfer results from animal experiments to the bedside.

Chronic sequelae of sepsis represent a major, yet underappreciated clinical problem, contributing to long-term mortality and quality-of-life impairment. In chronic liver disease, inflammation perpetuates fibrogenesis, but development of fibrosis in the post-acute phase of systemic inflammation has not been studied. Therefore, a mouse model of post-acute sequelae of sepsis was established based on polymicrobial peritonitis under antibiotic protection. Survival decreased to approximately 40% within 7 days and remained constant until day 28 (post-acute phase). In survivors, clinical recovery was observed within 1 week, whereas white blood cell and platelet count, as well as markers of liver injury, remained elevated until day 28. Macroscopically, inflammation and abscess formation were detected in the peritoneal space and on/in the liver. Microscopically, acute-chronic inflammation with ductular proliferation, focal granuloma formation in the parenchyma, and substantial hepatic fibrosis were observed. Increased numbers of potentially pathogenetic macrophages and α-smooth muscle actin-positive cells, presumably activated hepatic stellate cells, were detected in the vicinity of fibrotic areas. Fibrosis was associated with the presence of elastin and an augmented production/deposition of collagen types I and III. Microarray analyses revealed early activation of canonical and noncanonical pathways of hepatic stellate cell transdifferentiation. Thus, chronic sequelae of experimental sepsis were characterized by abscess formation, persistent inflammation, and substantial liver injury and fibrosis, the latter associated with increased numbers of macrophages/α-smooth muscle actin-positive cells and deposition of collagen types I and III. This suggests persistent activation of stellate cells, with consecutive fibrosis-a hallmark of chronic liver disease-as a result of acute life-threatening infection.

Background: Hepatic dysfunction and jaundice are traditionally viewed as late features of sepsis and portend poor outcomes. We hypothesized that changes in liver function occur early in the onset of sepsis, yet pass undetected by standard laboratory tests., Methods and Findings: In a long-term rat model of faecal peritonitis, biotransformation and hepatobiliary transport were impaired, depending on subsequent disease severity, as early as 6 h after peritoneal contamination. Phosphatidylinositol-3-kinase (PI3K) signalling was simultaneously induced at this time point. At 15 h there was hepatocellular accumulation of bilirubin, bile acids, and xenobiotics, with disturbed bile acid conjugation and drug metabolism. Cholestasis was preceded by disruption of the bile acid and organic anion transport machinery at the canalicular pole. Inhibitors of PI3K partially prevented cytokine-induced loss of villi in cultured HepG2 cells. Notably, mice lacking the PI3Kγ gene were protected against cholestasis and impaired bile acid conjugation. This was partially confirmed by an increase in plasma bile acids (e.g., chenodeoxycholic acid [CDCA] and taurodeoxycholic acid [TDCA]) observed in 48 patients on the day severe sepsis was diagnosed; unlike bilirubin (area under the receiver-operating curve: 0.59), these bile acids predicted 28-d mortality with high sensitivity and specificity (area under the receiver-operating curve: CDCA: 0.77; TDCA: 0.72; CDCA+TDCA: 0.87)., Conclusions: Liver dysfunction is an early and commonplace event in the rat model of sepsis studied here; PI3K signalling seems to play a crucial role. All aspects of hepatic biotransformation are affected, with severity relating to subsequent prognosis. Detected changes significantly precede conventional markers and are reflected by early alterations in plasma bile acids. These observations carry important implications for the diagnosis of liver dysfunction and pharmacotherapy in the critically ill. Further clinical work is necessary to extend these concepts into clinical practice. Please see later in the article for the Editors' Summary.

Background: Sepsis models are frequently based on induction of peritonitis, with cecal ligation and puncture reflecting the prototypical model. However, there is an ongoing discussion about the limitations of these models due to their variability in progression and outcome. Since standardization is a cornerstone of experimental models, we aimed to develop a reliable and reproducible procedure for induction of peritonitis., Materials and Methods: A human stool batch was processed for -80° storage. For induction of peritonitis in fluid-resuscitated rats, a defined volume of stool suspension from this batch was injected intraperitoneally. For characterization of the model, physiologic and inflammatory changes were evaluated after sepsis induction. Survival analyses with the same batch were repeated in four independent experiments over a time period of 16 mo., Results: The polymicrobial infection resulted in severe peritoneal inflammation with a systemic increase in cytokines. The mortality rate at 15 h was 29% and this was reproducible over a 16 mo time period. If antibiotic treatment was applied, a 50% survival was achieved. Laboratory markers indicated a progressive multi-organ dysfunction, while blood gas analysis showed respiratory compensation of a metabolic acidosis, and maintenance of PaO(2). Intravital microscopy of the liver revealed an impaired microcirculation. A decreased hemostatic potential was demonstrated by rotational thromboelastometry. Despite clinical recovery within 3 d, surviving animals showed laboratory and histologic signs of persisting inflammation even after 2 wk., Conclusions: This model reflects many features of human sepsis. Application of an infectious focus that is both quantitatively and qualitatively defined assures high reproducibility. Moreover, the procedure is simple and can be easily standardized., (Copyright © 2011 Elsevier Inc. All rights reserved.)