Pathological bacterial translocation in cirrhosis: pathophysiology, diagnosis and clinical implications

Probiotics as Potential Therapeutic Agents: Safeguarding Skeletal Muscle against Alcohol-Induced Damage through the Gut-Liver-Muscle Axis

Probiotics have shown the potential to counteract the loss of muscle mass, reduce physical fatigue, and mitigate inflammatory response following intense exercise, although the mechanisms by which they work are not very clear. The objective of this review is to describe the main harmful effects of alcohol on skeletal muscle and to provide important strategies based on the use of probiotics. The excessive consumption of alcohol is a worldwide problem and has been shown to be crucial in the progression of alcoholic liver disease (ALD), for which, to date, the only therapy available is lifestyle modification, including cessation of drinking. In ALD, alcohol contributes significantly to the loss of skeletal muscle, and also to changes in the intestinal microbiota, which are the basis for a series of problems related to the onset of sarcopenia. Some of the main effects of alcohol on the skeletal muscle are described in this review, with particular emphasis on the "gut-liver-muscle axis", which seems to be the primary cause of a series of muscle dysfunctions related to the onset of ALD. The modulation of the intestinal microbiota through probiotics utilization has appeared to be crucial in mitigating the muscle damage induced by the high amounts of alcohol consumed.

Allopurinol Prevents Cirrhosis-Related Complications: A Quadruple Blind Placebo-Controlled Trial

BACKGROUND

Complications associated with liver cirrhosis are various and potentially fatal. The treatment options to counteract hepatic decompensation are limited. Therefore, the study aimed to explore the use of allopurinol in preventing the recurrence of liver cirrhosis-related complications.

METHODS

One hundred patients with hepatic decompensation were randomized into 1:1 ratio to receive either allopurinol 300 mg or placebo tablets once daily for 6 months. The primary endpoint was the incidence of cirrhosis-related complications (overt ascites, spontaneous bacterial peritonitis, variceal bleeding, hepatorenal syndrome, and hepatic encephalopathy).

RESULTS

Six months following treatment, allopurinol reduced the relative risk (RR) of any first complication experienced after enrollment by 56% (hazard ratio [HR] 0.44; 95% confidence interval [CI], 0.27-0.62); P ˂ .001). Allopurinol decreased the RR of overt ascites by 67% (HR 0.33; 95% CI, 0.0098-0.94); P = .039] and reduced the RR of spontaneous bacterial peritonitis by about 75% (HR 0.25; 95% CI, 0.05-0.76; P = .01). Likewise, allopurinol was linked to an 80% reduction in the RR of developing hepatorenal syndrome (HR 0.2; 95% CI, 0.04-0.87; P = .033).

CONCLUSION

Allopurinol significantly decreased the recurrence of overall liver cirrhosis-related complications. Therefore, allopurinol may constitute a promising agent for patients with hepatic decompensation. These positive outcomes could be a result of its ability to reduce bacterial translocation and inflammation.

CLINICALTRIALS

GOV IDENTIFIER

NCT005545670.

Changes of the bacterial composition in duodenal fluid from patients with liver cirrhosis and molecular bacterascites

Small intestinal bacterial overgrowth and compositional changes of intestinal microbiota are pathomechanistic factors in liver cirrhosis leading to bacterial translocation and infectious complications. We analyzed the quantity and composition of duodenal bacterial DNA (bactDNA) in relation to bactDNA in blood and ascites of patients with liver cirrhosis. Duodenal fluid and corresponding blood and ascites samples from 103 patients with liver cirrhosis were collected. Non-liver disease patients (n = 22) served as controls. BactDNA was quantified by 16S-rRNA gene-based PCR. T-RFLP and 16S-rRNA amplicon sequencing were used to analyze bacterial composition. Duodenal bacterial diversity in cirrhosis was distinct to controls showing significantly higher abundances of Streptococcus, Enterococcus and Veillonella. Patients with bactDNA positive ascites revealed reduced spectrum of core microbiota with Streptococcus as key player of duodenal community and higher prevalence of Granulicatella proving presence of cirrhosis related intestinal dysbiosis. Regarding duodenal fluid bactDNA quantification, no significant differences were found between patients with cirrhosis and controls. Additionally, percentage of subjects with detectable bactDNA in blood did not differ between patients and controls. This study evaluated the diversity of bacterial DNA in different body specimens with potential implications on understanding how intestinal bacterial translocation may affect infectious complications in cirrhosis.

Diagnostic and Prognostic Value of IL-10, FABP2 and LPS Levels in HCC Patients

Hepatocellular carcinoma (HCC) still lacks valuable diagnostic and prognostic tools. This study aimed to investigate the potential diagnostic and prognostic value of baseline interleukin (IL)-10, fatty acid-binding protein 2 (FABP2) and lipopolysaccharide (LPS) levels in patients with HCC. Serum levels of IL-10, FABP2 and LPS in 47 newly diagnosed HCC patients and 50 healthy individuals were estimated and compared. The best cut-off points for baseline IL-10, FABP2 and LPS levels predicting overall survival (OS) were evaluated. Both levels of FABP2 and IL-10 were significantly higher in HCC patients vs. control group (median 2095 vs. 1772 pg/mL, p = 0.026; 9.94 vs. 4.89 pg/mL, p < 0.001) and may serve as potential biomarkers in complex HCC diagnostic tools. The cut-off value of 2479 pg/mL for FABP2 was determined to have the highest sensitivity (66.7%) and specificity (55.6%) to distinguish patients with a median OS longer than 17 months. However, the median OS of patients with high and low levels of FABP2 were not significantly different (p = 0.896). The prognostic value of LPS as well as FABP2 and IL-10 for HCC patients appears to be limited.

Small intestinal bacterial overgrowth: current update

PURPOSE OF REVIEW

This article aims to provide an up-to-date review of small intestinal bacterial overgrowth (SIBO), including etiology and risk factors, clinical manifestations, diagnostic evaluation for suspected SIBO, and therapeutic options.

RECENT FINDINGS

Recent advances in breath testing, capsule and urine-based testing have opened new avenues and improved diagnostic yield of SIBO. Nonantibiotic-based treatment strategies have shown promising results in initial trials.

SUMMARY

Small intestinal bacterial overgrowth (SIBO) is a condition defined by the excess bacteria or changes in bacterial composition of the small intestine. These are associated with various gastrointestinal (GI) symptoms such as bloating, abdominal distension, diarrhea, nutrient deficiencies, and even frank weight loss. Small bowel jejunal aspirate of >10 5 CFU/ml has traditionally been considered the gold standard for diagnosis. Glucose and lactulose breath testing have become more common in clinical practice as they are noninvasive, easily accessible, and have lower cost. Treatment focuses on the eradication of excess bacteria in the small bowel and is traditionally done with the use of oral antibiotics. Other emerging therapies may include probiotics, diet manipulation, and prokinetic agents.

Potential contribution of the gut microbiota to the development of portal vein thrombosis in liver cirrhosis

Background

Portal vein thrombosis (PVT) is a serious complication of liver cirrhosis (LC) and is closely related to gut homeostasis. The study aimed to investigate the composition of gut microbiota and its putative role in PVT development in LC.

Methods

33 patients with LC admitted between January 2022 and December 2022 were enrolled in this study. Based on imaging findings, they were categorized into LC without PVT (n = 21) and LC with PVT (n = 12) groups. Fecal samples were collected from each participant and underwent 16S rDNA sequencing.

Results

D-Dimer and platelet elevations were the main clinical features of LC with PVT. The alpha and beta diversity of the gut microbiota in LC with PVT group was found to be significantly higher compared to the control group. The structure of the gut microbiota was significantly different between the two groups. Based on LEfSe data, the genera Akkermansia, Eubacterium hallii group, Fusicatenibacter, and Anaerostipes were enriched in the LC with PVT, while Enterococcus, Weissella, Bacteroides, and Subdoligranulum were enriched in those of the LC subjects. Changes in microbiota structure result in significant differences in gut microbiota metabolism between the two groups. Altered levels of the microbiota genera were shown to be correlated with coagulation factor parameters. In animal experiments, the addition of Bacteroides reversed the CCl4-induced PVT.

Conclusion

Liver cirrhosis with PVT led to a disorder in the gut microbiota, which was characterized by an increase in pathogenic bacteria and a decrease in beneficial bacteria. Furthermore, modulating the gut microbiota, especially Bacteroides, may be a promising therapeutic approach to reduce the progression of PVT in LC.

Probiotic management and inflammatory factors as a novel treatment in cirrhosis: A systematic review and meta-analysis

The interaction between intestinal microecological dysregulation, altered inflammatory factors, and cirrhosis is unclear. The aim of this systematic review and meta-analysis was to synthesize the results of previous studies to assess the efficacy of probiotics in the treatment of cirrhosis and their effect on inflammatory factors, as well as to explore the relationship between gut microecological dysregulation and liver disease to gain a deeper understanding of this interaction. Up to December 2022, eligible studies were identified by searching the following databases: National Knowledge Infrastructure (CNKI), Wanfang Data, Web of Science, PubMed, Embase, Medline, and the Cochrane Library. Statistical analysis was performed using software RevMan Version 5.4. A total of 33 eligible randomized controlled trials were included in the study, and data on probiotic strains, duration of intervention, measures in the control group, and outcomes were extracted and evaluated. Compared to the control group, the experimental group had significant improvements in overall efficacy. The results of the meta-analysis revealed that probiotic use significantly decreased biochemical parameters for liver function, including aspartate transaminase, alanine aminotransferase, and total bilirubin. Similar result was obtained in interleukin-6, tumor necrosis factor-α, and endotoxin. However, probiotic intervention did not significantly affect interleukin-2 and interleukin-10. The current meta-analysis illustrates that probiotic supplementation reduces inflammatory markers and biochemical parameters for liver function in patients with cirrhosis, suggesting that probiotic management may be a novel treatment for cirrhosis. Furthermore, the interaction of the gut microbiota, associated metabolites, and inflammation factors with cirrhosis may provide a promising therapeutic target for the pharmacological and clinical treatment of cirrhosis.

Protective effect of water extracts of Veronicastrum latifolium (Hemsl.) Yamazaki on carbon tetrachloride-induced liver fibrosis in mice and its effect on intestinal flora

Liver fibrosis refers to a reversible event of repair and reconstruction following injury due to various etiologies, and its continuous development will lead to cirrhosis and liver cancer. Abnormal alterations in intestinal microbiota can hasten the development of hepatic fibrosis and damage. Veronicastrum latifolium (Hemsl.) Yamazaki (VLY) is a classic drug applied extensively for managing acute and chronic hepatitis, liver cirrhosis and ascites in ethnic minority areas of Guizhou Province, China, which possesses broad-spectrum pharmacological activities. In view of the crucial role of intestinal microbiota in the development of liver fibrosis, the present study attempted to investigate the effects of VLY aqueous extract on ameliorating CCl4-elicited liver fibrosis in mice and on intestinal microbiota and to explore its possible mechanism. Phytochemical analysis showed that VLY water extract contained a variety of components, particularly rich in organic acids and their derivatives, flavonoids, phenolic acids, nucleotides and their derivatives, carbohydrates and other compounds. VLY water extract remarkably alleviated CCl4-induced liver damage and fibrosis in mice, improved liver histology, and improved liver function abnormalities. VLY water extract also inhibited the activation of hepatic stellate cells and invasion of intrahepatic inflammatory cells. Additionally, sequencing the 16 s rDNA gene revealed that VLY water extract changed the intestinal microbiota composition in liver fibrotic mice. It elevated the Firmicutes/Bacteroidota ratio and enriched the relative Lactobacillus richness, which is capable of mitigating fibrosis and inflammation in impaired liver. In summary, through modulation of inflammation and intestinal microbiota, VLY water extract can reduce the CCl4-elicited liver fibrosis.

The Intestinal Microbiota in the Development of Chronic Liver Disease: Current Status

Chronic liver disease (CLD) is a significant global health burden, leading to millions of deaths annually. The gut-liver axis plays a pivotal role in this context, allowing the transport of gut-derived products directly to the liver, as well as biological compounds from the liver to the intestine. The gut microbiota plays a significant role in maintaining the health of the digestive system. A change in gut microbiome composition as seen in dysbiosis is associated with immune dysregulation, altered energy and gut hormone regulation, and increased intestinal permeability, contributing to inflammatory mechanisms and damage to the liver, irrespective of the underlying etiology of CLD. The aim of this review is to present the current knowledge about the composition of the intestinal microbiome in healthy individuals and those with CLD, including the factors that affect this composition, the impact of the altered microbiome on the liver, and the mechanisms by which it occurs. Furthermore, this review analyzes the effects of gut microbiome modulation on the course of CLD, by using pharmacotherapy, nutrition, fecal microbiota transplantation, supplements, and probiotics. This review opens avenues for the translation of knowledge about gut-liver interplay into clinical practice as an additional tool to fight CLD and its complications.

Pathophysiology of Hepatorenal Syndrome - Acute Kidney Injury

Hepatorenal syndrome is a complication of liver cirrhosis with ascites that results from the complex interplay of many pathogenetic mechanisms. Advanced cirrhosis is characterized by the development of hemodynamic changes of splanchnic and systemic arterial vasodilatation, with paradoxical renal vasoconstriction and renal hypoperfusion. Cirrhosis is also an inflammatory state. The inflammatory cascade is initiated by a portal hypertension-induced increased translocation of bacteria, bacterial products, and endotoxins from the gut to the splanchnic and then to the systemic circulation. The inflammation, whether sterile or related to infection, is responsible for renal microcirculatory dysfunction, microthrombi formation, renal tubular oxidative stress, and tubular damage. Of course, many of the bacterial products also have vasodilatory properties, potentially exaggerating the state of vasodilatation and worsening the hemodynamic instability in these patients. The presence of cardiac dysfunction, related to cirrhotic cardiomyopathy, with its associated systolic incompetence, can aggravate the mismatch between the circulatory capacitance and the circulation volume, worsening the extent of the effective arterial underfilling, with lower renal perfusion pressure, contributing to renal hypoperfusion and increasing the risk for development of acute kidney injury. The presence of tense ascites can exert an intra-abdominal compartmental syndrome effect on the renal circulation, causing renal congestion and hampering glomerular filtration. Other contributing factors to renal dysfunction include the tubular damaging effects of cholestasis and adrenal dysfunction. Future developments include the use of metabolomics to identify metabolic pathways that can lead to the development of renal dysfunction, with the potential of identifying biomarkers for early diagnosis of renal dysfunction and the development of treatment strategies.

Gut Microbiota and Antibiotic Treatments for the Main Non-Oncologic Hepato-Biliary-Pancreatic Disorders

The gut microbiota is a pivotal actor in the maintenance of the balance in the complex interconnections of hepato-biliary-pancreatic system. It has both metabolic and immunologic functions, with an influence on the homeostasis of the whole organism and on the pathogenesis of a wide range of diseases, from non-neoplastic ones to tumorigenesis. The continuous bidirectional metabolic communication between gut and hepato-pancreatic district, through bile ducts and portal vein, leads to a continuous interaction with translocated bacteria and their products. Chronic liver disease and pancreatic disorders can lead to reduced intestinal motility, decreased bile acid synthesis and intestinal immune dysfunction, determining a compositional and functional imbalance in gut microbiota (dysbiosis), with potentially harmful consequences on the host's health. The modulation of the gut microbiota by antibiotics represents a pioneering challenge with striking future therapeutic opportunities, even in non-infectious diseases. In this setting, antibiotics are aimed at harmonizing gut microbial function and, sometimes, composition. A more targeted and specific approach should be the goal to pursue in the future, tailoring the treatment according to the type of microbiota modulation to be achieved and using combined strategies.

Acute kidney injury in patients with acute-on-chronic liver failure: clinical significance and management

Acute-on-chronic-liver failure (ACLF) refers to a phenomenon in which patients with chronic liver disease develop multiple organ failure due to acute exacerbation of underlying liver disease. More than 10 definitions of ACLF are extant around the world, and there is lack of consensus on whether extrahepatic organ failure is a main component or a consequence of ACLF. Asian and European consortiums have their own definitions of ACLF. The Asian Pacific Association for the Study of the Liver ACLF Research Consortium does not consider kidney failure as a diagnostic criterion for ACLF. Meanwhile, the European Association for the Study of the Liver Chronic Liver Failure and the North American Consortium for the Study of End-stage Liver Disease do consider kidney failure as an important factor in diagnosing and assessing the severity of ACLF. When kidney failure occurs in ACLF patients, treatment varies depending on the presence and stage of acute kidney injury (AKI). In general, the diagnosis of AKI in cirrhotic patients is based on the International Club of Ascites criteria: an increase of 0.3 mg/dL or more within 48 hours or a serum creatinine increase of 50% or more within one week. This study underscores the importance of kidney failure or AKI in patients with ACLF by reviewing its pathophysiology, prevention methods, and treatment approaches.

Gut Dysbiosis and Blood-Brain Barrier Alteration in Hepatic Encephalopathy: From Gut to Brain

A common neuropsychiatric complication of advanced liver disease, hepatic encephalopathy (HE), impacts the quality of life and length of hospital stays. There is new evidence that gut microbiota plays a significant role in brain development and cerebral homeostasis. Microbiota metabolites are providing a new avenue of therapeutic options for several neurological-related disorders. For instance, the gut microbiota composition and blood-brain barrier (BBB) integrity are altered in HE in a variety of clinical and experimental studies. Furthermore, probiotics, prebiotics, antibiotics, and fecal microbiota transplantation have been shown to positively affect BBB integrity in disease models that are potentially extendable to HE by targeting gut microbiota. However, the mechanisms that underlie microbiota dysbiosis and its effects on the BBB are still unclear in HE. To this end, the aim of this review was to summarize the clinical and experimental evidence of gut dysbiosis and BBB disruption in HE and a possible mechanism.

The microbiota and the gut-liver axis in primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) offers unique opportunities to explore the gut-liver axis owing to the close association between liver disease and colonic inflammation. It is well established that the gut microbiota in people with PSC differs from that of healthy individuals, but details of the microbial factors that demarcate PSC from inflammatory bowel disease (IBD) without PSC are poorly understood. In this Review, we aim to provide an overview of the latest literature on the gut microbiome in PSC and PSC with IBD, critically examining hypotheses on how microorganisms could contribute to the pathogenesis of PSC. A particular emphasis will be put on pathogenic features of the gut microbiota that might explain the occurrence of bile duct inflammation and liver disease in the context of IBD, and we postulate the potential existence of a specific yet unknown factor related to the gut-liver axis as causative in PSC. Available data are scrutinized in the perspective of therapeutic approaches related to the gut-liver axis.

Is it possible to intervene early cirrhosis by targeting toll-like receptors to rebalance the intestinal microbiome?

Cirrhosis is a progressive chronic liver disease caused by one or more causes and characterized by diffuse fibrosis, pseudolobules, and regenerated nodules. Once progression to hepatic decompensation, the function of the liver and other organs is impaired and almost impossible to reverse and recover, which often results in hospitalization, impaired quality of life, and high mortality. However, in the early stage of cirrhosis, there seems to be a possibility of cirrhosis reversal. The development of cirrhosis is related to the intestinal microbiota and activation of toll-like receptors (TLRs) pathways, which could regulate cell proliferation, apoptosis, expression of the hepatomitogen epiregulin, and liver inflammation. Targeting regulation of intestinal microbiota and TLRs pathways could affect the occurrence and development of cirrhosis and its complications. In this paper, we first reviewed the dynamic change of intestinal microbiota and TLRs during cirrhosis progression. And further discussed the interaction between them and potential therapeutic targets to reverse early staged cirrhosis.

Improving Management of Portal Hypertension: The Potential Benefit of Non-Etiological Therapies in Cirrhosis

Portal hypertension is the consequence of cirrhosis and results from increased sinusoidal vascular resistance and hepatic blood inflow. Etiological therapies represent the first intervention to prevent a significant increase in portal pressure due to chronic liver damage. However, other superimposed pathophysiological drivers may worsen liver disease, including inflammation, bacterial translocation, endothelial dysfunction, and hyperactivation of hemostasis. These mechanisms can be targeted by a specific class of drugs already used in clinical practice. Albumin, rifaximin, statins, aspirin, and anticoagulants have been tested in cirrhosis and were a topic of discussion in the last Baveno consensus as non-etiological therapies. Based on the pathogenesis of portal hypertension in cirrhosis, our review summarizes the main mechanisms targeted by these drugs as well as the clinical evidence that considers them a valid complementary option to manage patients with cirrhosis and portal hypertension.

Role of gut microbiota in the pathogenesis and therapeutics of minimal hepatic encephalopathy via the gut-liver-brain axis

Minimal hepatic encephalopathy (MHE) is a frequent neurological and psychiatric complication of liver cirrhosis. The precise pathogenesis of MHE is complicated and has yet to be fully elucidated. Studies in cirrhotic patients and experimental animals with MHE have indicated that gut microbiota dysbiosis induces systemic inflammation, hyperammonemia, and endotoxemia, subsequently leading to neuroinflammation in the brain via the gut-liver-brain axis. Related mechanisms initiated by gut microbiota dysbiosis have significant roles in MHE pathogenesis. The currently available therapeutic strategies for MHE in clinical practice, including lactulose, rifaximin, probiotics, synbiotics, and fecal microbiota transplantation, exert their effects mainly by modulating gut microbiota dysbiosis. Microbiome therapies for MHE have shown promised efficacy and safety; however, several controversies and challenges regarding their clinical use deserve to be intensively discussed. We have summarized the latest research findings concerning the roles of gut microbiota dysbiosis in the pathogenesis of MHE via the gut-liver-brain axis as well as the potential mechanisms by which microbiome therapies regulate gut microbiota dysbiosis in MHE patients.

The Mechanisms of Systemic Inflammatory and Immunosuppressive Acute-on-Chronic Liver Failure and Application Prospect of Single-Cell Sequencing

Acute-on-chronic liver failure (ACLF) is a complex clinical syndrome, and patients often have high short-term mortality. It occurs with intense systemic inflammation, often accompanied by a proinflammatory event (such as infection or alcoholic hepatitis), and is closely related to single or multiple organ failure. Liver inflammation begins when innate immune cells (such as Kupffer cells (KCs)) are activated by binding of pathogen-associated molecular patterns (PAMPs) from pathogenic microorganisms or damage-associated molecular patterns (DAMPs) of host origin to their pattern recognition receptors (PRRs). Activated KCs can secrete inflammatory factors as well as chemokines and recruit bone marrow-derived cells such as neutrophils and monocytes to the liver to enhance the inflammatory process. Bacterial translocation may contribute to ACLF when there are no obvious precipitating events. Immunometabolism plays an important role in the process (including mitochondrial dysfunction, amino acid metabolism, and lipid metabolism). The late stage of ACLF is mainly characterized by immunosuppression. In this process, the dysfunction of monocyte and macrophage is reflected in the downregulation of HLA-DR and upregulation of MER tyrosine kinase (MERTK), which weakens the antigen presentation function and reduces the secretion of inflammatory cytokines. We also describe the specific function of bacterial translocation and the gut-liver axis in the process of ACLF. Finally, we also describe the transcriptomics in HBV-ACLF and the recent progress of single-cell RNA sequencing as well as its potential application in the study of ACLF in the future, in order to gain a deeper understanding of ACLF in terms of single-cell gene expression.

Bile duct anastomosis does not promote bacterial contamination of autologous blood salvaged during living donor liver transplantation

Bile duct surgeries are conventionally considered to promote bacterial contamination of the surgical field. However, liver transplantation recipients' bile produced by the newly implanted liver graft from healthy living donors may be sterile. We tested bacterial contamination of autologous blood salvaged before and after bile duct anastomosis (BDA) during living donor liver transplantation (LDLT). In 29 patients undergoing LDLT, bacterial culture was performed for four blood samples and one bile sample: two from autologous blood salvaged before BDA (one was nonleukoreduced and another was leukoreduced), two from autologous blood salvaged after BDA (one was nonleukoreduced and another was leukoreduced), and one from bile produced in the newly implanted liver graft. The primary outcome was bacterial contamination. The risk of bacterial contamination was not significantly different between nonleukoreduced autologous blood salvaged before BDA and nonleukoreduced autologous blood salvaged after BDA (44.8% and 31.0%; odds ratio 0.33, 95% confidence interval 0.03-1.86; p = 0.228). No bacteria were found after leukoreduction in all 58 autologous blood samples. All bile samples were negative for bacteria. None of the 29 patients, including 13 patients who received salvaged autologous blood positive for bacteria, developed postoperative bacteremia. We found that bile from the newly implanted liver graft is sterile in LDLT and BDA does not increase the risk of bacterial contamination of salvaged blood, supporting the use of blood salvage during LDLT even after BDA. Leukoreduction converted all autologous blood samples positive for bacteria to negative. The clinical benefit of leukoreduction for salvaged autologous blood on post-LDLT bacteremia needs further research.

Gut Barrier Damage and Gut Translocation of Pathogen Molecules in Lupus, an Impact of Innate Immunity (Macrophages and Neutrophils) in Autoimmune Disease

The gut barrier is a single cell layer that separates gut micro-organisms from the host, and gut permeability defects result in the translocation of microbial molecules from the gut into the blood. Despite the silent clinical manifestation, gut translocation of microbial molecules can induce systemic inflammation that might be an endogenous exacerbating factor of systemic lupus erythematosus. In contrast, circulatory immune-complex deposition and the effect of medications on the gut, an organ with an extremely large surface area, of patients with active lupus might cause gut translocation of microbial molecules, which worsens lupus severity. Likewise, the imbalance of gut microbiota may initiate lupus and/or interfere with gut integrity which results in microbial translocation and lupus exacerbation. Moreover, immune hyper-responsiveness of innate immune cells (macrophages and neutrophils) is demonstrated in a lupus model from the loss of inhibitory Fc gamma receptor IIb (FcgRIIb), which induces prominent responses through the cross-link between activating-FcgRs and innate immune receptors. The immune hyper-responsiveness can cause cell death, especially apoptosis and neutrophil extracellular traps (NETosis), which possibly exacerbates lupus, partly through the enhanced exposure of the self-antigens. Leaky gut monitoring and treatments (such as probiotics) might be beneficial in lupus. Here, we discuss the current information on leaky gut in lupus.

Hepatorenal Syndrome and Other Post-Liver Transplantation Complications: Case Studies and Literature Review

Hepatorenal syndrome (HRS) was originally defined as a renal dysfunction caused by a decreased renal perfusion due to hemodynamic disturbances in the arterial circulation and an excessive activity of endogenous vasoactive systems in the course of cirrhosis. Considering the latest research, this syndrome may have a more complex pathomechanism. Equally often as in cirrhosis, HRS develops after orthotopic liver transplantation (OLTx) and worsens the prognosis significantly increasing mortality rates in this patient population. The prevalence of renal complications after OLTx and their negative prognostic impact on the survival of both the graft and the recipient prompted the authors of this work to analyze in detail 2 cases of HRS after OLTx to indicate the multiplicity of factors contributing to the pathophysiology of this syndrome. Attention was paid to risk factors for HRS found in the anamnesis before OLTx, especially a pre-existing renal dysfunction. In both cases early post-OLTx complications associated with the transplantation procedure were described: destabilization of the circulatory system, transfusions of blood products, prolonged stay at an intensive care unit, and necessity of introducing continuous renal replacement therapy. In the later period after the OLTx, infections (bacterial, fungal, viral) and drug nephrotoxicity, including the activity of immunosuppressants (tacrolimus), contributed primarily to the renal function impairment.

Enterococcus raffinosus, Enterococcus durans and Enterococcus avium Isolated from a Tertiary Care Hospital in Romania-Retrospective Study and Brief Review

(1) Background: This paper aims to provide a description of non-faecalis non-faecium enterococci isolated from a tertiary care hospital in Romania and to briefly review the existing literature regarding the involvement of Enterococcus raffinosus, Enterococcus durans and Enterococcus avium in human infections and their antimicrobial resistance patterns; (2) Methods: We retrospectively analyzed all Enteroccocus species isolated from the “Prof. Dr. O. Fodor” Regional Institute of Gastroenterology and Hepatology from Cluj-Napoca during one year focusing on non-faecalis non-faecium Enterococci. A brief review of the literature was performed using case reports involving Enterococcus raffinosus, Enterococcus durans and Enterococcus avium; (3) Results: Only 58 out of 658 Enteroccocus isolates were non-faecalis non-faecium and met the inclusion criteria. These species were isolated more often (p < 0.05) from the surgical ward from mixed etiology infections with E. coli. In our review, we included 39 case reports involving E. raffinosus, E. durans and E. avium; (4) Conclusions: Isolation of non-faecalis non-faecium enterococci displays an emerging trend with crucial healthcare consequences. Based on the analysis of the case reports, E. avium seems to be involved more often in neurological infections, E. durans in endocarditis, while E. raffinosus displays a more heterogenous distribution.

Glucocorticoid Treatment Strategies in Liver Failure

Liver failure is characterized by serious liver decompensation and high mortality. The activation of systemic immune responses and systemic inflammation are widely accepted as the core pathogenesis of liver failure. Glucocorticoids (GCs) are most regularly utilized to suppress excessive inflammatory reactions and immunological responses. GCs have been used in the clinical treatment of liver failure for nearly 60 years. While there has been no unanimity on the feasibility and application of GC treatment in liver failure until recently. The most recent trials have produced conflicting results when it comes to the dose and time for GC therapy of different etiology of liver failure. Our review outlines the issues and options in managing GC treatment in liver failure based on an investigation of the molecular mechanism that GC may give in the treatment.

Neutrophil Extracellular Traps in Severe SARS-CoV-2 Infection: A Possible Impact of LPS and (1→3)-β-D-glucan in Blood from Gut Translocation

Due to limited data on the link between gut barrier defects (leaky gut) and neutrophil extracellular traps (NETs) in coronavirus disease 2019 (COVID-19), blood samples of COVID-19 cases—mild (upper respiratory tract symptoms without pneumonia; n = 27), moderate (pneumonia without hypoxia; n = 28), and severe (pneumonia with hypoxia; n = 20)—versus healthy control (n = 15) were evaluated, together with in vitro experiments. Accordingly, neutrophil counts, serum cytokines (IL-6 and IL-8), lipopolysaccharide (LPS), bacteria-free DNA, and NETs parameters (fluorescent-stained nuclear morphology, dsDNA, neutrophil elastase, histone–DNA complex, and myeloperoxidase–DNA complex) were found to differentiate COVID-19 severity, whereas serum (1→3)-β-D-glucan (BG) was different between the control and COVID-19 cases. Despite non-detectable bacteria-free DNA in the blood of healthy volunteers, using blood bacteriome analysis, proteobacterial DNA was similarly predominant in both control and COVID-19 cases (all severities). In parallel, only COVID-19 samples from moderate and severe cases, but not mild cases, were activated in vitro NETs, as determined by supernatant dsDNA, Peptidyl Arginine Deiminase 4, and nuclear morphology. With neutrophil experiments, LPS plus BG (LPS + BG) more prominently induced NETs, cytokines, NFκB, and reactive oxygen species, when compared with the activation by each molecule alone. In conclusion, pathogen molecules (LPS and BG) from gut translocation along with neutrophilia and cytokinemia in COVID-19-activated, NETs-induced hyperinflammation.

Impaired antibacterial response of liver sinusoidal Vγ9+Vδ2+ T cells in patients with chronic liver disease

OBJECTIVE

The liver acts as a frontline barrier against diverse gut-derived pathogens, and the sinusoid is the primary site of liver immune surveillance. However, little is known about liver sinusoidal immune cells in the context of chronic liver disease (CLD). Here, we investigated the antibacterial capacity of liver sinusoidal γδ T cells in patients with various CLDs.

DESIGN

We analysed the frequency, phenotype and functions of human liver sinusoidal γδ T cells from healthy donors and recipients with CLD, including HBV-related CLD (liver cirrhosis (LC) and/or hepatocellular carcinoma (HCC)), alcoholic LC and LC or HCC of other aetiologies, by flow cytometry and RNA-sequencing using liver perfusates obtained during living donor liver transplantation. We also measured the plasma levels of D-lactate and bacterial endotoxin to evaluate bacterial translocation.

RESULTS

The frequency of liver sinusoidal Vγ9⁺Vδ2⁺ T cells was reduced in patients with CLD. Immunophenotypic and transcriptomic analyses revealed that liver sinusoidal Vγ9⁺Vδ2⁺ T cells from patients with CLD were persistently activated and pro-apoptotic. In addition, liver sinusoidal Vγ9⁺Vδ2⁺ T cells from patients with CLD showed significantly decreased interferon (IFN)-γ production following stimulation with bacterial metabolites and Escherichia coli. The antibacterial IFN-γ response of liver sinusoidal Vγ9⁺Vδ2⁺ T cells significantly correlated with liver function, and inversely correlated with the plasma level of D-lactate in patients with CLD. Repetitive in vitro stimulation with E. coli induced activation, apoptosis and functional impairment of liver sinusoidal Vγ9⁺Vδ2⁺ T cells.

CONCLUSION

Liver sinusoidal Vγ9⁺Vδ2⁺ T cells are functionally impaired in patients with CLD. Bacterial translocation and decreasing liver functions are associated with functional impairment of liver sinusoidal Vγ9⁺Vδ2⁺ T cells.

Circulating microbiome in patients with portal hypertension

Portal hypertension (PH) in liver cirrhosis leads to increased gut permeability and the translocation of bacteria across the gut-liver axis. Microbial DNA has recently been detected in different blood compartments; however, this phenomenon has not been thoroughly analyzed in PH. This study aimed to explore circulating bacterial DNA signatures, inflammatory cytokines, and gut permeability markers in different blood compartments (peripheral and hepatic veins) of patients with cirrhosis and PH. The 16S rRNA blood microbiome profiles were determined in 58 patients with liver cirrhosis and 46 control patients. Taxonomic differences were analyzed in relation to PH, liver function, inflammatory cytokines, and gut permeability markers. Circulating plasma microbiome profiles in patients with cirrhosis were distinct from those of the controls and were characterized by enrichment of Comamonas, Cnuella, Dialister, Escherichia/Shigella, and Prevotella and the depletion of Bradyrhizobium, Curvibacter, Diaphorobacter, Pseudarcicella, and Pseudomonas. Comparison of peripheral and hepatic vein blood compartments of patients with cirrhosis did not reveal differentially abundant taxa. Enrichment of the genera Bacteroides, Escherichia/Shigella, and Prevotella was associated with severe PH (SPH) in both blood compartments; however, circulating microbiome profiles could not predict PH severity. Escherichia/Shigella and Prevotella abundance was correlated with IL-8 levels in the hepatic vein. In conclusion, we demonstrated a distinct circulating blood microbiome profile in patients with cirrhosis, showing that specific bacterial genera in blood are marginally associated with SPH, Model for End-Stage Liver Disease score, and inflammation biomarkers; however, circulating microbial composition failed to predict PH severity.

Blood Bacteria-Free DNA in Septic Mice Enhances LPS-Induced Inflammation in Mice through Macrophage Response

Although bacteria-free DNA in blood during systemic infection is mainly derived from bacterial death, translocation of the DNA from the gut into the blood circulation (gut translocation) is also possible. Hence, several mouse models with experiments on macrophages were conducted to explore the sources, influences, and impacts of bacteria-free DNA in sepsis. First, bacteria-free DNA and bacteriome in blood were demonstrated in cecal ligation and puncture (CLP) sepsis mice. Second, administration of bacterial lysate (a source of bacterial DNA) in dextran sulfate solution (DSS)-induced mucositis mice elevated blood bacteria-free DNA without bacteremia supported gut translocation of free DNA. The absence of blood bacteria-free DNA in DSS mice without bacterial lysate implies an impact of the abundance of bacterial DNA in intestinal contents on the translocation of free DNA. Third, higher serum cytokines in mice after injection of combined bacterial DNA with lipopolysaccharide (LPS), when compared to LPS injection alone, supported an influence of blood bacteria-free DNA on systemic inflammation. The synergistic effects of free DNA and LPS on macrophage pro-inflammatory responses, as indicated by supernatant cytokines (TNF-α, IL-6, and IL-10), pro-inflammatory genes (NFκB, iNOS, and IL-1β), and profound energy alteration (enhanced glycolysis with reduced mitochondrial functions), which was neutralized by TLR-9 inhibition (chloroquine), were demonstrated. In conclusion, the presence of bacteria-free DNA in sepsis mice is partly due to gut translocation of bacteria-free DNA into the systemic circulation, which would enhance sepsis severity. Inhibition of the responses against bacterial DNA by TLR-9 inhibition could attenuate LPS-DNA synergy in macrophages and might help improve sepsis hyper-inflammation in some situations.

Bacteraemia, sepsis and antibiotic resistance in Australian patients with cirrhosis: a population-based study

Objective

Multiple factors predispose patients with cirrhosis to sepsis and/or bacteraemia and this has a high mortality rate. Within different geographical regions there are marked differences in the prevalence of infection with multidrug-resistant organisms (MDR). This study examined risk factors for and outcomes of sepsis/bacteraemia in public hospital admissions with cirrhosis in the state of Queensland, Australia, over the last decade, along with the bacterial pathogens responsible and their antibiotic susceptibility profiles.

Design

A population-based retrospective cohort study of public hospital admissions was conducted from 1 January 2008 to 31 December 2017. Hospital admissions for patients with a diagnosis of cirrhosis were categorised by the presence or absence of sepsis/bacteraemia. Clinical and sociodemographic information including cirrhosis aetiology, complications and comorbidities, and in-hospital mortality were examined using bivariate and multivariate analyses. In patients with bacteraemia, the type and prevalence of bacteria and antibiotic resistance was assessed.

Results

Sepsis/bacteraemia was present in 3951 of 103 165 hospital admissions with a diagnosis of cirrhosis. Factors associated with sepsis/bacteraemia included disease aetiology, particularly primary sclerosing cholangitis (adj-OR 15.09, 95% CI 12.24 to 18.60), alcohol (adj-OR 2.90, 95% CI 2.71 to 3.09), Charlson Comorbidity Index ≥3 (adj-OR 3.54, 95% CI 3.19 to 3.93) and diabetes (adj-OR 1.87, 95% CI 1.74 to 2.01). Overall case-fatality rate among admissions with sepsis/bacteraemia was 27.7% (95% CI 26.3% to 29.1%) vs 3.7% (95% CI 3.6% to 3.8%) without sepsis/bacteraemia. In-hospital death was significantly associated with sepsis/bacteraemia (adj-OR 6.50, 95% CI 5.95 to 7.11). The most common organisms identified were Escherichia coli and Staphylococcus aureus, present in 22.9% and 18.1%, respectively, of the 2265 admissions with a positive blood culture. The prevalence of MDR bacteria was low (5.6%)

Conclusion

Morbidity and mortality related to sepsis/bacteraemia in patients with cirrhosis remains a critical clinical problem.

Albumin Substitution in Decompensated Liver Cirrhosis: Don't Forget Zinc

Decompensated liver cirrhosis has a dismal prognosis, with patients surviving on average for 2-4 years after the first diagnosis of ascites. Albumin is an important tool in the therapy of cirrhotic ascites. By virtue of its oncotic properties, it reduces the risk of cardiovascular dysfunction after paracentesis. Treatment with albumin also counteracts the development of hepatorenal syndrome and spontaneous bacterial peritonitis. More recently, the positive impact of long-term albumin supplementation in liver disease, based on its pleiotropic non-oncotic activities, has been recognized. These include transport of endo- and exogenous substances, anti-inflammatory, antioxidant and immunomodulatory activities, and stabilizing effects on the endothelium. Besides the growing recognition that effective albumin therapy requires adjustment of the plasma level to normal physiological values, the search for substances with adjuvant activities is becoming increasingly important. More than 75% of patients with decompensated liver cirrhosis do not only present with hypoalbuminemia but also with zinc deficiency. There is a close relationship between albumin and the essential trace element zinc. First and foremost, albumin is the main carrier of zinc in plasma, and is hence critical for systemic distribution of zinc. In this review, we discuss important functions of albumin in the context of metabolic, immunological, oxidative, transport, and distribution processes, alongside crucial functions and effects of zinc and their mutual dependencies. In particular, we focus on the major role of chronic inflammatory processes in pathogenesis and progression of liver cirrhosis and how albumin therapy and zinc supplementation may affect these processes.

Recent insights into the characteristics and role of peritoneal macrophages from ascites of cirrhotic patients

Macrophages are a diverse myeloid cell population involved in innate and adaptive immune responses, embryonic development, wound repair, and regulation of tissue homeostasis. These cells link the innate and adaptive immunities and are crucial in the development and sustainment of various inflammatory diseases. Macrophages are tissue-resident cells in steady-state conditions; however, they are also recruited from blood monocytes after local pathogen invasion or tissue injury. Peritoneal macrophages vary based on their cell complexity, phenotype, and functional capabilities. These cells regulate inflammation and control bacterial infections in the ascites of decompensated cirrhotic patients. Our recent work reported several phenotypic and functional characteristics of these cells under both healthy and pathological conditions. A direct association between cell size, CD14/CD16 expression, intracellular level of GATA-6, and expression of CD206 and HLA-DR activation/maturation markers, indicate that the large peritoneal macrophage CD14^highCD16^high subset constitutes the mature phenotype of human resident peritoneal macrophages during homeostasis. Moreover, elevated expression of CD14/CD16 is related to the phagocytic capacity. The novel large CD14^highCD16^high peritoneal subpopulation is increased in the ascites of cirrhotic patients and is highly sensitive to lipopolysaccharide (LPS)-induced activation, thereby exhibiting features of inflammatory priming. Thus, phosphorylation of ERK1/2, PKB/Akt, and c-Jun is remarkably increased in response to LPS in vitro, whereas that of p38 MAPK is reduced compared with the monocyte-derived macrophages from the blood of healthy controls. Furthermore, in vitro activated monocyte-derived macrophages from ascites of cirrhotic patients secreted significantly higher levels of IL-6, IL-10, and TNF-α and lower amounts of IL-1β and IL-12 than the corresponding cells from healthy donor’s blood. Based on these results, other authors have recently reported that the surface expression level of CD206 can be used to identify mature, resident, inflammatory peritoneal macrophages in patients with cirrhosis. Soluble CD206 is released from activated large peritoneal macrophages, and increased concentrations in patients with cirrhosis and spontaneous bacterial peritonitis (SBP) indicate reduced odds of survival for 90 d. Hence, the level of soluble CD206 in ascites might be used to identify patients with SBP at risk of death. In conclusion, peritoneal macrophages present in ascites of cirrhotic patients display multiple phenotypic modifications characterized by reduced ratio of cells expressing several membrane markers, together with an increase in the ratios of complex and intermediate subpopulations and a decrease in the classic-like subset. These modifications may lead to the identification of novel pharmaceutical targets for prevention and treatment of hepatic damage.

Leaky Gut and Gut-Liver Axis in Liver Cirrhosis: Clinical Studies Update

Portal blood flows into the liver containing the gut microbiome and its products such as endotoxin and bacterial DNA. The cirrhotic liver acts and detoxifies as the initial site of microbial products. In so-called "leaky gut," the increased intestinal permeability for bacteria and their products constitutes an important pathogenetic factor for major complications in patients with liver cirrhosis. Prolonged gastric and small intestinal transit may induce intestinal bacterial overgrowth, a condition in which colonic bacteria translocate into the small gut. Cirrhotic patients further show gut dysbiosis characterized by an overgrowth of potentially pathogenic bacteria and a decrease in autochthonous nonpathogenic bacteria. Pathological bacterial translocation (BT) is a contributing factor in the development of various severe complications. Bile acids (BAs) undergo extensive enterohepatic circulation and play important roles in the gut-liver axis. BT-induced inflammation prevents synthesis of BAs in the liver through inhibition of BA-synthesizing enzyme CYP7A1. A lower abundance of 7α-dehydroxylating gut bacteria leads to decreased conversion of primary to secondary BAs. Decreases in total and secondary BAs may play an important role in the gut dysbiosis characterized by a proinflammatory and toxic gut microbiome inducing BT and endotoxemia, as addressed in my previous reviews. Selective intestinal decontamination by the use of various antimicrobial drugs for management of complications has a long history. Lactobacillus GG decreasing endotoxemia is reported to improve the microbiome with beneficial changes in amino acid, vitamin and secondary BA metabolism. Current approaches for hepatic encephalopathy are the use of nonabsorbable antibiotics and disaccharides. Probiotics may become an additional therapeutic option for advanced liver cirrhosis.

Fecal Microbiota Transplantation Is Safe and Effective in Patients With Clostridioides difficile Infection and Cirrhosis

BACKGROUND & AIMS

Clostridioides difficile infection (CDI) harms a large proportion of patients with cirrhosis. Fecal microbiota transplantation (FMT) is recommended for recurrent CDI, but its effects in patients with cirrhosis have not been established. We performed a multicenter observational study to evaluate the efficacy and safety of FMT for CDI in patients with cirrhosis.

METHODS

We performed a retrospective study of 63 adults with cirrhosis (median model for end-stage liver disease score, 14.5; 24 patients with decompensated cirrhosis) who underwent FMT for CDI from January 2012 through November 2018 at 8 academic centers in the United States, Canada, and Italy. We collected data on patient demographics and characteristics of cirrhosis, CDI, and FMT from medical records and compared differences among patients with different severities of cirrhosis, and FMT successes vs failures at the 8-week follow-up evaluation. We also obtained data on adverse events (AEs) and severe AEs within 12 weeks of FMT.

RESULTS

Patients underwent FMT for recurrent CDI (55 of 63; 87.3%), severe CDI (6 of 63; 9.5%), or fulminant CDI (2 of 63; 3.2%) primarily via colonoscopy (59 of 63; 93.7%) as outpatients (47 of 63; 76.8%). FMT success was achieved for 54 patients (85.7%). Among FMT failures, a higher proportion used non-CDI antibiotics at the time of FMT (44.4% vs 5.6%; P < .001), had Child-Pugh scores of B or C (100% vs 37.7%; P < .001), used probiotics (77.8% vs 24.1%; P = .003), had pseudomembranes (22.2% vs 0; P = .018), and underwent FMT as inpatients (45.5% vs 19%; P = .039), compared with FMT successes. In multivariable analysis, use of non-CDI antibiotics at the time of FMT (odds ratio, 17.43; 95% CI, 2.00-152.03; P = .01) and use of probiotics (odds ratio, 11.9; 95% CI, 1.81-78.3; P = .01) were associated with a greater risk of FMT failure. FMT-related AEs occurred in 33.3% of patients (21 of 63)-most were self-limited abdominal cramps or diarrhea. There were only 5 severe AEs that possibly were related to FMT; none involved infection or death.

CONCLUSIONS

In a retrospective study, we found FMT to be safe and effective for the treatment of CDI in patients with cirrhosis.

Assessment of Pyroptosis-Related Indicators as Potential Biomarkers and Their Association with Severity in Patients with Liver Cirrhosis

Purpose

The diagnosis and management of liver cirrhosis remain challenging due to its diverse clinical manifestations and elusive severity evaluation. Pyroptosis, an identified inflammatory form of cell death, has recently been reported to participate in cirrhosis development. Nonetheless, the clinical significance of pyroptosis in liver cirrhosis remains largely unexplored.

Patients and Methods

One hundred and fifty-one liver cirrhosis patients either alone or in combination with various complications and twenty-nine gender- and age-matched healthy controls (HCs) were enrolled in this study. Pyroptosis-related indicators gasdermin D (GSDMD), IL-1ß and IL-18 were measured by IHC in tissue section and by ELISA in serum, respectively, and correlations of their circulating levels with disease severity as well as their potential as biomarkers for monitoring cirrhosis progression were evaluated.

Results

Increased levels of the circulating pyroptosis-related indicators GSDMD, IL-1ß and IL-18 were observed in liver cirrhosis patients, especially those with an etiology of viral infection. In addition, all three indicators were positively correlated with disease severity parameters, including Child-Pugh classification, APRI scores and compensated status. Furthermore, receiver operating characteristic (ROC) analysis showed that circulating IL-1ß exerted potential discriminating power for SBP occurrence in liver cirrhosis, but GSDMD possessed differentiating power for SBP in liver cirrhosis with ascites, which yielded area under the ROC curve (AUC) of 0.81 and 0.80, respectively.

Conclusion

Liver cirrhosis patients exhibited increased levels of circulating GSDMD, IL-1ß and IL-18, all of which were positively correlated with disease severity. More importantly, the identified circulating IL-1ß and GSDMD exhibited potentials as novel biomarkers for liver cirrhosis patients presenting with SBP.

Genetically engineered E. coli Nissle attenuates hyperammonemia and prevents memory impairment in bile-duct ligated rats

Hyperammonemia associated with chronic liver disease (CLD) is implicated in the pathogenesis of hepatic encephalopathy (HE). The gut is a major source of ammonia production that contributes to hyperammonemia in CLD and HE and remains the primary therapeutic target for lowering hyperammonemia. As an ammonia-lowering strategy, Escherichia coli Nissle 1917 bacterium was genetically modified to consume and convert ammonia to arginine (S-ARG). S-ARG was further modified to additionally synthesize butyrate (S-ARG + BUT). Both strains were evaluated in bile-duct ligated (BDL) rats; experimental model of CLD and HE.

METHODS

One-week post-surgery, BDLs received non-modified EcN (EcN), S-ARG, S-ARG + BUT (3x10¹¹ CFU/day) or vehicle until sacrifice at 3 or 5 weeks. Plasma (ammonia/pro-inflammatory/liver function), liver fibrosis (hydroxyproline), liver mRNA (pro-inflammatory/fibrogenic/anti-apoptotic) and colon mRNA (pro-inflammatory) biomarkers were measured post-sacrifice. Memory, motor-coordination, muscle-strength and locomotion were assessed at 5 weeks.

RESULTS

In BDL-Veh rats, hyperammonemia developed at 3 and further increased at 5 weeks. This rise was prevented by S-ARG and S-ARG + BUT, whereas EcN was ineffective. Memory impairment was prevented only in S-ARG + BUT vs BDL-Veh. Systemic inflammation (IL-10/MCP-1/endotoxin) increased at 3 and 5 weeks in BDL-Veh. S-ARG + BUT attenuated inflammation at both timepoints (except 5-week endotoxin) vs BDL-Veh, whereas S-ARG only attenuated IP-10 and MCP-1 at 3 weeks. Circulating ALT/AST/ALP/GGT/albumin/bilirubin and gene expression of liver function markers (IL-10/IL-6/IL-1β/TGF-β/α-SMA/collagen-1α1/Bcl-2) were not normalized by either strain. Colonic mRNA (TNF-α/IL-1β/occludin) markers were attenuated by synthetic strains at both timepoints vs BDL-Veh.

CONCLUSION

S-ARG and S-ARG + BUT attenuated hyperammonemia, with S-ARG + BUT additional memory protection likely due to greater anti-inflammatory effect. These innovative strategies, particularly S-ARG + BUT, have potential to prevent HE.

Systemic Inflammatory Response Syndrome in Patients Hospitalized for Acute Decompensation of Cirrhosis

BACKGROUND

Although recently challenged, systemic inflammatory response syndrome (SIRS) criteria are still commonly used in daily practice to define sepsis. However, several factors in liver cirrhosis may negatively impact its prognostic ability. Goals. To investigate the factors associated with the presence of SIRS, the characteristics of SIRS related to infection, and its prognostic value among patients hospitalized for acute decompensation of cirrhosis. Study. In this cohort study from two tertiary hospitals, 543 patients were followed up, up to 90 days. Data collection, including the prognostic models, was within 48 hours of admission.

RESULTS

SIRS was present in 42.7% of the sample and was independently associated with upper gastrointestinal bleeding (UGB), ACLF, infection, and negatively related to beta-blockers. SIRS was associated with mortality in univariate analysis, but not in multiple Cox regression analysis. The Kaplan-Meier survival probability of patients without SIRS was 73.0% and for those with SIRS was 64.7%. The presence of SIRS was not significantly associated with mortality when considering patients with or without infection, separately. Infection in SIRS patients was independently associated with Child-Pugh C and inversely related to UGB. Among subjects with SIRS, mortality was independently related to the presence of infection, ACLF, and Child-Pugh C.

CONCLUSIONS

SIRS was common in hospitalized patients with cirrhosis and was of no prognostic value, even in the presence of infection.

Non-alcoholic fatty liver disease is associated with bacterial translocation and a higher inflammation response in psoriatic patients

Psoriasis and non-alcoholic fatty liver disease (NAFLD) are both inflammatory diseases. The study objective was to estimate the risk of NAFLD, non-alcoholic steatohepatitis, and liver fibrosis (by liver stiffness and liver biopsy) in patients with psoriasis and to determine the epidemiological, clinical, immunological (TNF-α, IL-2, IL-6, IL-12, IL-17, IL-23, and TGF-β) characteristics, and bacterial translocation. Of the 215 psoriatic patients included, 91 presented NAFLD (prevalence: 42.3%). Compared to patients with psoriasis alone, those with NAFLD were significantly more likely to have metabolic syndrome, diabetes, dyslipidemia, body mass index ≥ 30 kg/m², homeostatic model assessment of insulin resistance ≥ 2.15, and greater psoriasis area severity index. NAFLD patients also had significantly higher levels of TNF-α (p = 0.002) and TGF-β (p = 0.007) and a higher prevalence of bacterial translocation (29.7% vs. 13.7%; p = 0.004). Liver stiffness measurement was over 7.8 kPa in 17.2% (15/87) of NAFLD patients; 13 of these underwent liver biopsy, and 5.7% (5/87) had liver fibrosis, while 1.1% (1/87) had advanced fibrosis or non-alcoholic steatohepatitis. In conclusion the prevalence of NAFLD in patients with psoriasis is high and associated with a higher prevalence of metabolic syndrome features, bacterial translocation and a higher pro-inflammatory state. It is worth mentioning that liver fibrosis and non-alcoholic steatohepatitis are not frequent in this population of patients.

Non-selective beta-blocker use in cirrhotic patients is associated with a reduced likelihood of hospitalisation for infection

BACKGROUND

Non-selective beta-blockers (NSBBs) reduce enteric bacterial translocation rates and the frequency of spontaneous bacterial peritonitis (SBP) in animal models.

AIM

To evaluate the effect of NSBBs on infection-related admissions.

METHODS

We performed a case-control study of cirrhotic patients' first in-patient admission between 1 January 2011 and 31 December 2016. We examined NSBB use and the development of infection. We performed a propensity score-matched analysis in those with NSBB use vs no use and calculated odds ratios on this matched cohort to determine the odds of outcomes based on NSBB use.

RESULTS

We identified 2165 cirrhotic patients who met our inclusion criteria. Most patients were Caucasian (69%), male (62%). Admission Model for End stage Liver Disease (MELD) score, Charlson comorbidity index and Child-Pugh score were 12 ± 1, 4 ± 2, and 8 ± 2, respectively. Ascites was the most common complication of portal hypertension (44%); 23% of patients used NSBBs at home. Infections occurred in 33% of admissions. In the propensity score-matched cohort, the use of NSBBs at home was associated with lower overall, and specific, infections. The effect was similar in patients taking NSBBs for either primary or secondary oesophageal variceal prophylaxis and for those on NSBBs for other indications. Patients not on NSBBs had higher odds of infection (OR = 2.5), SBP (OR = 4.0), and bacteraemia (OR = 6.0).

CONCLUSION

Home use of NSBBs by patients with cirrhosis was associated with fewer infection-related admissions. The data suggest that NSBBs in this group of patients reduce the risk of infection.

Current progress of research on intestinal bacterial translocation

Under normal conditions, the intestinal flora and the body are in dynamic equilibrium. When the barrier function of the intestinal tract is damaged due to various reasons, changes in the number and proportion of bacteria or spatial displacement result in bacterial translocation (BT), which ultimately leads to multiple organ dysfunction syndrome (MODS). Endogenous infections and endotoxemia caused by intestinal flora and endotoxin translocation are the origins of inflammatory responses, and the intestinal tract is the organ in which MODS both initiates and targets. Only by ensuring the integrity of the intestinal mucosal barrier can intestinal BT be effectively prevented. Elimination of the primary disease and maintaining blood and oxygen supply to the intestine is the most basic treatment. Early initiation of the intestinal tract, establishment of enteral nutrition, and selective digestive decontamination are also highly effective treatments. Early diagnosis, intervention, or prevention of BT may be a new avenue or important connection in the treatment of various diseases. The mechanism of BT, detection techniques, prevention and treatment, and its interaction with parenteral diseases were reviewed.

Gut-liver crosstalk in sepsis-induced liver injury

Sepsis is characterized by a dysregulated immune response to infection leading to life-threatening organ dysfunction. Sepsis-induced liver injury is recognized as a powerful independent predictor of mortality in the intensive care unit. During systemic infections, the liver regulates immune defenses via bacterial clearance, production of acute-phase proteins (APPs) and cytokines, and metabolic adaptation to inflammation. Increased levels of inflammatory cytokines and impaired bacterial clearance and disrupted metabolic products can cause gut microbiota dysbiosis and disruption of the intestinal mucosal barrier. Changes in the gut microbiota play crucial roles in liver injury during sepsis. Bacterial translocation and resulting intestinal inflammation lead to a systemic inflammatory response and acute liver injury. The gut-liver crosstalk is a potential target for therapeutic interventions. This review analyzes the underlying mechanisms for the gut-liver crosstalk in sepsis-induced liver injury.

Clinical Characteristics and Risk Factors for Bloodstream Infection Due to Carbapenem-Resistant Klebsiella pneumoniae in Patients with Hematologic Malignancies

Purpose

The aim was to examine the clinical characteristics and risk factors for bloodstream infection (BSI) due to carbapenem-resistant Klebsiella pneumoniae (CRKP) in patients with hematologic malignancies.

Materials and Methods

A single-centre, retrospective case–control study representing 734 patients with hematologic malignancies between January 1, 2017, and December 31, 2018, was conducted. Demographic and clinical data were collected from the hospital electronic medical records system.

Results

Among the 734 patients with hematologic malignancies, 3% (22/734) of the patients developed CRKP BSI during their hospitalization. Overall 28-day all-cause mortality reached 77.3% (17/22). Patients with Pitt bacteremia score (PBS) >4, pneumonia and septic shock were more frequent in the non-survivors versus the survivors. Compared with the non-survivors in antimicrobial treatment, combination therapy of tigecycline and polymyxin B was more common in the survivors. The independent risk factors associated with CRKP BSI were CRKP rectal colonization (OR, 11.067; CI=4.43–27.644; P<0.001; 3 points), severe neutropenia (OR, 4.095; CI=0.876–19.141; P=0.073; 1 point) and invasive mechanical ventilation (IMV) within the previous 30 days to onset of BSI (OR, 18.444; CI=1.787–190.343; P=0.014; 4 points). The total risk score of ≥5 indicated that the probability of CRKP BSI occurrence was above 48%.

Conclusion

CRKP BSI in patients with hematologic malignancies is associated with high mortality. The risk factor-based prediction model might help clinicians to start prompt effective anti-infective therapy in patients with suspicion of CRKP BSI and improve outcomes.

Discrimination of ascitic fluid infection in malignant ascites by polymorphonuclear neutrophil ratio and count: Investigating the validity of count ≥250/mm3 as the one-size-fits-all criterion

AIM

Neutrocytic ascites, traditionally defined as a polymorphonuclear neutrophil count ≥250/mm³ , is infrequently reported during paracenteses to relieve malignant ascites (MA). This study aims to explore new potential diagnostic criteria to discriminate ascitic fluid infection associated with MA and to examine the clinical and laboratory characteristics of neutrocytic ascites.

METHODS

The investigators retrospectively collected data on paracenteses to relieve MA at the Emergency Department of National Cancer Center, Korea, from January 2014 to February 2017. We analyzed the patients whose ascites fulfilled the traditional criteria for classification as neutrocytic ascites; polymorphonuclear neutrophils ≥250/mm³ with no history of either hepatocellular carcinoma or liver cirrhosis.

RESULTS

In total, 1467 patients underwent paracentesis to relieve MA. Excluding 98 follow-up paracenteses cases, 112 cases (8.2%) showed neutrocytic ascites. Of these 112 patients, 27 (24.1%) had positive culture results. Receiver-operating characteristic analysis indicated that the area under the curve (AUC) values were 0.90 (95% CI 0.82-0.95) and 0.86 (95% CI 0.78-0.92) for polymorphonuclear neutrophil ratio and count, respectively. The difference between the two AUCs was not statistically significant (P = .29). Moreover, the best cutoff points were 70% and 1500/mm³ for polymorphonuclear neutrophil ratio and count, respectively. In addition, extensive liver metastasis was a significant independent risk factor of MA associated with ascitic fluid infection.

CONCLUSIONS

Both polymorphonuclear neutrophil ratio and count had good discriminative abilities for culture results in MA. Polymorphonuclear neutrophil ratio was somewhat better despite lacking statistical significance compared to polymorphonuclear neutrophil count, with 70% as best cutoff.

Current Status and Prospects of Spontaneous Peritonitis in Patients with Cirrhosis

Spontaneous bacterial peritonitis (SBP) is a common cirrhotic ascites complication which exacerbates the patient's condition. SBP is caused by gram-negative bacilli and, to a lesser extent, gram-positive cocci. Hospital-acquired infections show higher levels of drug-resistant bacteria. Geographical location influences pathogenic bacteria distribution; therefore, different hospitals in the same country record different bacteria strains. Intestinal changes and a weak immune system in patients with liver cirrhosis lead to bacterial translocation thus causing SBP. Early diagnosis and timely treatment are important in SBP management. When the treatment effect is not effective, other rare pathogens should be explored.

Vitamin D-related immunomodulation in patients with liver cirrhosis

OBJECTIVE(S)

Increasing evidence indicates that vitamin D status is linked to severity of liver cirrhosis and patients' survival. However, the potential role of vitamin D-related immunomodulation in hepatic decompensation and patients' mortality in relation to vitamin D deficiency remains unknown. The aim of the current study is to evaluate the association between vitamin D status and vitamin D binding protein (VDBP) levels with serum cytokine and lipopolysaccharide binding protein (LBP) and to examine their role on disease severity and cirrhotics' mortality.

METHODS

One hundred consecutive Caucasian patients with liver cirrhosis were enrolled in the study. 25(OH)D, VDBP, and LBP concentrations were assessed by ELISA. Cytokine tumor necrosis factor-a (TNF-a), interleukin 6 (IL-6), IL-1β, IL-8, IL-10, and IL-12 levels were determined by Cytometric Bead Array.

RESULTS

25(OH)D levels were inversely correlated with CP score, MELD, IL-6, and CP stage and VDBP levels with CP score, MELD, IL-6, IL-8, LBP, and CP stage. Cirrhotics with 25(OH)D deficiency and severe deficiency had significantly higher CP score, increased IL-6 levels and lower VDBP levels. In the multivariate analysis, the independent prognostic factors associated with patients' survival were CP stage B [hazard ratio = 6.75; 95% confidence interval (CI) 1.32, 34.43; P = 0.022], CP stage C (hazard ratio = 7.39; 95% CI 1.41, 38.81; P = 0.018), the presence of hepatocellular carcinoma (hazard ratio = 4.50; 95% CI 1.54, 13.13; P = 0.006) and 25(OH)D levels (hazard ratio = 0.87; 95% CI 0.80, 0.95; P = 0.002).

CONCLUSION

The results show that vitamin D status and VDBP levels are associated with liver cirrhosis severity and patients' mortality, possibly through a proinflammatory immune response.

Minimal Hepatic Encephalopathy: Effect of H. pylori infection and small intestinal bacterial overgrowth treatment on clinical outcomes

The effect Helicobacter pylori (Hp) infection and small intestinal bacterial over growth (SIBO) in minimal hepatic encephalopathy (MHE) is not well understood. The aim of the study was to determine the effect of eradication of Hp infection and SIBO treatment on MHE in patients with cirrhosis. Patients with cirrhosis were enrolled and MHE was determined by psychometric tests and critical flicker frequency analysis. Hp infection and SIBO were assessed by urea breath and Hydrogen breath tests respectively in patients with cirrhosis and in healthy volunteers. Patients with Hp infection and SIBO were given appropriate treatment. At six weeks follow-up, presence of Hp infection, SIBO and MHE status was reassessed. Ninety patients with cirrhosis and equal number of healthy controls were included. 55 (61.1%) patients in the cirrhotic group were diagnosed to have underlying MHE. Among cirrhotic group, Hp infection was present in 28 with MHE (50.9%) vs. in 15 without MHE (42.8%) (p = 0.45). Similarly, SIBO was present in 17 (30.9%) vs. 11 (31.4%) (p = 0.95) in patients with and without MHE respectively. In comparison with healthy controls, patients with cirrhosis were more frequently harboring Hp and SIBO (47.7% vs. 17.7% (p < 0.001) and 31.1% vs. 4.4% (p < 0.001) respectively. On follow-up, all patients showed evidence of eradication of Hp and SIBO infection. Treatment of SIBO significantly improved the state of MHE in cirrhotics, however eradication of Hp infection did not improve MHE significantly. Additionally, patients with low Model for End-Stage Liver Disease (MELD) score and belonging to Child class B had significantly better improvement in MHE. A large number of patients with cirrhosis had either active Hp infection or SIBO with or without MHE, compared to healthy controls. Treatment of SIBO significantly improved MHE in patients with cirrhosis, whereas eradication of Hp did not affect the outcome of MHE in these patients.

Safety of TNF inhibitors in rheumatic disease in case of NAFLD and cirrhosis

The management of inflammatory rheumatic diseases has substantially changed in recent years, as has the profile of patients. The advent of biotherapies has been a revolution in rheumatology and the impact of co-morbidities in the management of these patients is now becoming increasingly important. Metabolic syndrome (MetS) is one of the most frequent comorbidities, and hepatic complications of MetS are not uncommon. MetS is responsible for Non-alcoholic fatty liver disease (NAFLD), characterized by excessive hepatic fat accumulation. In extreme cases, progression to cirrhosis is possible. NAFLD ranks among the top three indications for liver transplantation. We review available data on the safety, especially the risk of infections, of TNF inhibitors (TNFi) in case of NAFLD and in case of liver cirrhosis, in patients with rheumatic disease. In cases of NAFLD without severe fibrosis, available data are reassuring and tend to show a beneficial effect of TNFi on hepatic tissue. In case of cirrhosis, data are conflicting. Further large, well-designed studies are needed to explore this specific issue.

Pathophysiology of Hepatic Encephalopathy

Hepatic encephalopathy (HE) is one of the major clinical decompensations of cirrhosis, with a high impact on health care resource utilization and cost. For an effective and comprehensive management of HE, the clinicians need to understand the pathophysiologic mechanisms of HE. This review describes the multiorgan processes involved in HE and how several HE precipitants and treatment strategies act on ammonia production, excretion, and neurotoxicity, including the impact of diabetes and use of cannabinoids. The authors also discuss the current and future role of gut microbiome, systemic/central inflammation, and various neurotransmitters for the pathogenesis and treatment of HE.

Risk stratification for early bacteremia after living donor liver transplantation: a retrospective observational cohort study

BACKGROUND

This study investigated perioperative clinical risk factors for early post-transplant bacteremia in patients undergoing living donor liver transplantation (LDLT). Additionally, postoperative outcomes were compared between patients with and without early post-transplant bacteremia.

METHODS

Clinical data of 610 adult patients who underwent elective LDLT between January 2009 and December 2018 at Seoul St. Mary's Hospital were retrospectively collected. The exclusion criteria included overt signs of infection within 1 month before surgery. A total of 596 adult patients were enrolled in this study. Based on the occurrence of a systemic bacterial infection after surgery, patients were classified into non-infected and infected groups.

RESULTS

The incidence of bacteremia at 1 month after LDLT was 9.7% (57 patients) and Enterococcus faecium (31.6%) was the most commonly cultured bacterium in the blood samples. Univariate analysis showed that preoperative psoas muscle index (PMI), model for end-stage disease score, utility of continuous renal replacement therapy (CRRT), ascites, C-reactive protein to albumin ratio, neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio, and sodium level, as well as intraoperative post-reperfusion syndrome, mean central venous pressure, requirement for packed red blood cells and fresh frozen plasma, hourly fluid infusion and urine output, and short-term postoperative early allograft dysfunction (EAD) were associated with the risk of early post-transplant bacteremia. Multivariate analysis revealed that PMI, the CRRT requirement, the NLR, and EAD were independently associated with the risk of early post-transplant bacteremia (area under the curve: 0.707; 95% confidence interval: 0.667-0.745; p < 0.001). The overall survival rate was better in the non-infected patient group. Among patients with bacteremia, anti-bacterial treatment was unable to resolve infection in 34 patients, resulting in an increased risk of patient mortality. Among the factors included in the model, EAD was significantly correlated with non-resolving infection.

CONCLUSIONS

We propose a prognostic model to identify patients at high risk for a bloodstream bacterial infection; furthermore, our findings support the notion that skeletal muscle depletion, CRRT requirement, systemic inflammatory response, and delayed liver graft function are associated with a pathogenic vulnerability in cirrhotic patients who undergo LDLT.

Genetic variants of innate immunity receptors are associated with mortality in cirrhotic patients with bacterial infection

BACKGROUND & AIMS

Acute-on-chronic liver failure (ACLF) is characterized by acute decompensation of cirrhosis (AD), organ failure(s) and high risk of short-term mortality with bacterial infection frequently as precipitating event. Innate immune pattern recognition receptors and members of the lectin pathway of complement activation are crucial to the innate immune response to pathogens. The aim of this study was to investigate whether single nucleotide polymorphisms (SNPs) of innate immune components are associated with the occurrence of bacterial infections or mortality in patients with cirrhosis hospitalized for AD or ACLF.

METHODS

Twenty-one innate immunity SNPs with known functional implications were genotyped in 826 AD/ACLF patients included in the CANONIC study. Associations between baseline characteristics of the patients, the occurrence of bacterial infections and survival rate at 90 days of follow-up in relation to the innate immunity genetic variants were analysed.

RESULTS

The NOD2-G908R genetic variant was associated with mortality (HR 2.25, P = .004) independently of age and MELD Score. This association was also found in a predefined subgroup analysis in patients with bacterial infections (HR 2.78, P < .001) along with MBL_Yx (HR 1.72, P = .008) and MASP2_371 (HR 1.67, P = .012) genetic variants. None of the analysed SNPs were significantly associated with the occurrence of acute bacterial infections or spontaneous bacterial peritonitis in particular.

CONCLUSIONS

Innate immune system-specific NOD2-G908R, MBL_Yx and MASP2_371 genetic variants were independently associated with increased risk of short-term mortality in AD/ACLF patients with bacterial infection.