Gut microflora in the pathogenesis of the complications of cirrhosis

High serum lipopolysaccharide binding protein is associated with increased mortality in patients with decompensated cirrhosis

BACKGROUND & AIMS

Lipopolysaccharide-binding-protein (LBP) is an acute-phase-protein produced by hepatocytes. Changes in LBP are associated with the dynamics of bacterial translocation and intestinal permeability in decompensated cirrhosis (DC). We assessed serum and ascitic-fluid (AF) LBP and examined their association with mortality in patients with DC.

METHODS

Eighty-eight consecutive patients (73.9% males) underwent thorough diagnostic investigations for infection. LBP (ng/mL) was assessed in serum (N=88) and AF (n=49) by enzyme-linked-immunosorbent-assay and expressed in natural logarithm (ln).

RESULTS

Serum lnLBP was higher in 18 patients with overt infection compared to those without (P<.001). Serum and AF lnLBP 13.49 and 12.11 displayed a very good-negative-predictive value of 90% and 95.1% to rule out infection and spontaneous-bacterial-peritonitis (SBP), respectively. LBP was higher in serum than in AF (P<.001). Serum and AF LBP levels showed a positive correlation with surrogate markers of inflammation. Patients without overt infection were prospectively followed up. The 90-day-mortality rate was 48% and 24.4% in patients with high (≥13.49) and low (<13.49) lnLBP, respectively, (log rank P=0.045). In univariate Cox regression analysis, neutrophils, LBP, MELD score and CRP were predictive of mortality. However, only high LBP (HR 8.1 95%CI 2.0-31.5, P=0.003) and MELD (HR 1.1 95%CI 1.0-1.2, P=0.002) were predictive of mortality in multivariate analysis.

CONCLUSIONS

Serum and AF LBP concentrations showed a high negative-predictive-value to exclude infection and SBP, respectively. High serum LBP was detected in patients without infection at presentation who died during the 90-day-follow-up period. Elevated serum LBP is a marker of short-term mortality in patients without overt bacterial infection.

Immune Dysfunction in Cirrhosis

Cirrhosis due to any etiology disrupts the homeostatic role of liver in the body. Cirrhosis-associated immune dysfunction leads to alterations in both innate and acquired immunity, due to defects in the local immunity of liver as well as in systemic immunity. Cirrhosis-associated immune dysfunction is a dynamic phenomenon, comprised of both increased systemic inflammation and immunodeficiency, and is responsible for 30% mortality. It also plays an important role in acute as well as chronic decompensation. Immune paralysis can accompany it, which is characterized by increase in anti-inflammatory cytokines and suppression of proinflammatory cytokines. There is also presence of increased gut permeability, reduced gut motility and altered gut flora, all of which leads to increased bacterial translocation. This increased bacterial translocation and consequent endotoxemia leads to increased blood stream bacterial infections that cause systemic inflammatory response syndrome, sepsis, multiorgan failure and death. The gut microbiota of cirrhotic patients has more pathogenic microbes than that of non-cirrhotic individuals, and this disturbs the homeostasis and favors gut translocation. Prompt diagnosis and treatment of such infections are necessary for better survival. We have reviewed the various mechanisms of immune dysfunction and its consequences in cirrhosis. Recognizing the exact pathophysiology of immune dysfunction will help treating clinicians in avoiding its complications in their patients and can lead to newer therapeutic interventions and reducing the morbidity and mortality rates.

Bacterial translocation aggravates CCl4-induced liver cirrhosis by regulating CD4+ T cells in rats

Bacterial translocation (BT) is thought to play an important role in the development of liver cirrhosis, but the mechanisms have not been fully explored. This study aims to investigate the distribution of Treg (CD3+CD4+CD25+Foxp3+), Th17 (CD3+CD4+IL-17+), and Th1 (CD3+CD4+IFN-γ+) cells in the intestinal lamina propria, liver and blood and to explore their relationships with BT. Cirrhotic rats with ascites were induced by CCl4. We found that there were lower levels of total protein and albumin, lower albumin/globulin ratio, lower body weight and higher spleen weight and ascites volume in cirrhotic rats with than without BT. We found that BT may cause increase of Treg cells in the proximal small intestine and decrease of Th17 cells in the whole intestine and blood in cirrhotic rats. It may also aggravate the CCl4-induced decrease in Th1 cells in the whole intestine, liver, caecum, and blood and the CCl4-induced increase in Th17 cells in the liver and Tregs in the distal small intestine, colon, and liver. Our data suggest that BT may aggravate liver injury and decrease liver function via an interaction with CD4+ T Cells. The results of this study may be helpful for the development of new treatments for liver cirrhosis.

Gut microbiome and liver disease

Gut microbiota changes are important in determining the occurrence and progression of chronic liver disease related to alcohol, nonalcoholic fatty liver disease, and cirrhosis. Specifically, the systemic inflammation, endotoxemia, and the vasodilation that leads to complications such as spontaneous bacterial peritonitis and hepatic encephalopathy could be related to the gut milieu. Given the poor prognosis of these events, their prevention and early management are essential. Microbiota may be an essential component of the gut milieu that can impact these clinical events, and the study of their composition and function in a culture-independent manner could help understand the prognosis. Recent human and animal studies have shown that the relative abundance and the functional changes of microbiota in the stool, colonic mucosa, and saliva have varying consequences on the presence and prognosis of chronic liver disease and cirrhosis. The impact of therapies on the microbiota is slowly being understood and will likely lead to a more targeted approach to gut microbiota modification in chronic liver disease and cirrhosis.

Rifaximin Decreases the Incidence and Severity of Acute Kidney Injury and Hepatorenal Syndrome in Cirrhosis

BACKGROUND

While the effects of rifaximin have been shown to be protective against acute kidney injury (AKI) and hepatorenal syndrome (HRS) in alcohol-induced cirrhosis, its long-term effects on the renal function of other cirrhotic patients are unknown.

AIM

To examine the long-term effects of rifaximin on the renal function of patients with cirrhosis from various etiologies.

METHODS

In a retrospective study, we examined cirrhotic patients at the University of Chicago Liver Clinic from January 1, 2011, to December 31, 2014. The study enrolled patients on rifaximin for ≥90 days, who were then matched by age, gender, and MELD score to a control group. Patients with malignancy and renal replacement therapy (RRT) at baseline were excluded. Data were censored at the last follow-up, termination of rifaximin therapy, initiation of RRT, death, or liver transplant.

RESULTS

Eighty-eight rifaximin cases were identified and matched to 88 control cases. Baseline characteristics were similar, with the exceptions of more prevalent long-term midodrine use (≥90 days) (17.0 vs 4.5 %, p = 0.01) and baseline ascites (37.5 vs 23.8 %, p = 0.05) in the rifaximin group. There was no difference in the frequency of infections, deaths, liver transplants, or hospitalizations. After controlling for cofounders, the incidence rate ratio of AKI (IRR 0.71, p = 0.02) and HRS (IRR 0.21, p = 0.02), as well as the risk of requiring RRT (OR 0.23, p = 0.01), was lower in the rifaximin group.

CONCLUSIONS

Long-term use of rifaximin is associated with a decrease incidence of AKI and HRS and a decrease risk of requiring RRT in a general population of cirrhotic patients.

Cirrhosis related functionality characteristic of the fecal microbiota as revealed by a metaproteomic approach

BACKGROUND

Intestinal microbiota operated as a whole and was closely related with human health. Previous studies had suggested close relationship between liver cirrhosis (LC) and gut microbiota.

METHODS

To determine the functional characteristic of the intestinal microbiota specific for liver cirrhosis, the fecal metaproteome of three LC patients with Child-Turcotte-Pugh (CTP) score of A, B, and C, and their spouse were first compared using high-throughput approach based on denaturing polyacrylamide gel electrophoresis and liquid chromatography-tandem mass spectrometry in our study.

RESULTS

A total of 5,020 proteins (88 % from bacteria, 12 % form human) were identified and annotated based on the GO and KEGG classification. Our results indicated that the LC patients possessed a core metaproteome including 119 proteins, among which 14 proteins were enhanced expressed and 7 proteins were unique for LC patients compared with the normal, which were dominant at the function of carbohydrate metabolism. In addition, LC patients have unique biosynthesis of branched chain amino acid (BCAA), pantothenate, and CoA, enhanced as CTP scores increased. Those three substances were all important in a wide array of key and essential biological roles of life.

CONCLUSIONS

We observed a highly comparable cirrhosis-specific metaproteome clustering of fecal microbiota and provided the first supportive evidence for the presence of a LC-related substantial functional core mainly involved in carbohydrate, BCAA, pantothenate, and CoA metabolism, suggesting the compensation of intestinal microbiota for the fragile and innutritious body of cirrhotic patients.

The pathophysiology of thrombocytopenia in chronic liver disease

Thrombocytopenia is the most common hematological abnormality encountered in patients with chronic liver disease (CLD). In addition to being an indicator of advanced disease and poor prognosis, it frequently prevents crucial interventions. Historically, thrombocytopenia has been attributed to hypersplenism, which is the increased pooling of platelets in a spleen enlarged by congestive splenomegaly secondary to portal hypertension. Over the past decade, however, there have been significant advances in the understanding of thrombopoiesis, which, in turn, has led to an improved understanding of thrombocytopenia in cirrhosis. Multiple factors contribute to the development of thrombocytopenia and these can broadly be divided into those that cause decreased production, splenic sequestration, and increased destruction. Depressed thrombopoietin levels in CLD, together with direct bone marrow suppression, result in a reduced rate of platelet production. Thrombopoietin regulates both platelet production and maturation and is impaired in CLD. Bone marrow suppression can be caused by viruses, alcohol, iron overload, and medications. Splenic sequestration results from hypersplenism. The increased rate of platelet destruction in cirrhosis also occurs through a number of pathways: increased shear stress, increased fibrinolysis, bacterial translocation, and infection result in an increased rate of platelet aggregation, while autoimmune disease and raised titers of antiplatelet immunoglobulin result in the immunologic destruction of platelets. An in-depth understanding of the complex pathophysiology of the thrombocytopenia of CLD is crucial when considering treatment strategies. This review outlines the recent advances in our understanding of thrombocytopenia in cirrhosis and CLD.

Microbiome and bacterial translocation in cirrhosis

Qualitative and quantitative changes in gut microbiota play a very important role in cirrhosis. Humans harbour around 100 quintillion gut bacteria, thus representing around 10 times more microbial cells than eukaryotic ones. The gastrointestinal tract is the largest surface area in the body and it is subject to constant exposure to these living microorganisms. The existing symbiosis, proven by the lack of proinflammatory response against commensal bacteria, implies the presence of clearly defined communication lines that contribute to the maintenance of homeostasis of the host. Therefore, alterations of gut flora seem to play a role in the pathogenesis and progress of multiple liver and gastrointestinal diseases. This has made its selective modification into an area of high therapeutic interest. Bacterial translocation is defined as the migration of bacteria or bacterial products from the intestines to the mesenteric lymph nodes. It follows that alteration in gut microbiota have shown importance, at least to some extent, in the pathogenesis of several complications arising from terminal liver disease, such as hepatic encephalopathy, portal hypertension and spontaneous bacterial peritonitis. This review sums up, firstly, how liver disease can alter the common composition of gut microbiota, and secondly, how this alteration contributes to the development of complications in cirrhosis.

Metagenomics: A New Way to Illustrate the Crosstalk between Infectious Diseases and Host Microbiome

Microbes have co-evolved with human beings for millions of years. They play a very important role in maintaining the health of the host. With the advancement in next generation sequencing technology, the microbiome profiling in the host can be obtained under different circumstances. This review focuses on the current knowledge of the alteration of complex microbial communities upon the infection of different pathogens, such as human immunodeficiency virus, hepatitis B virus, influenza virus, and Mycobacterium tuberculosis, at different body sites. It is believed that the increased understanding of the correlation between infectious disease and the alteration of the microbiome can contribute to better management of disease progression in the future. However, future studies may need to be more integrative so as to establish the exact causality of diseases by analyzing the correlation between microorganisms within the human host and the pathogenesis of infectious diseases.

Alcoholic hepatitis and HCV interactions in the modulation of liver disease

Most HCV-infected patients regularly consume alcohol. Alcoholic liver disease (ALD) and chronic hepatitis C virus (HCV) infection together are the most common causes of liver disease worldwide. Although both factors independently cause liver disease, they synergistically promote rapid liver disease progression with devastating outcomes for patients. This review focuses on the prevalence, clinical characteristics and molecular pathophysiologic mechanisms of HCV infection associated with alcohol abuse. Recent findings have centred on the synergistic effect of alcohol and HCV on viral replication, hepatocyte apoptosis, oxidative stress, alcohol-induced 'leaky gut', miR-122 and immune dysregulation. Clinical and basic research findings presented here summarize key scientific findings with the aim of highlighting potential areas for new therapies and identifying ways of optimizing current treatments for alcoholics with HCV infection.

Role of systemic inflammation in cirrhosis: From pathogenesis to prognosis

The natural history of cirrhosis can be divided into an initial stage, known as compensated cirrhosis, and an advanced stage which encompasses both decompensated cirrhosis and acute-on-chronic liver failure (ACLF). The latter syndrome has been recently described as an acute deterioration of liver function in patients with cirrhosis, which is usually triggered by a precipitating event and results in the failure of one or more organs and high short-term mortality rates. Each stage is characterized by distinctive clinical manifestations and prognoses. One of the key elements involved in cirrhosis physiopathology is systemic inflammation, recently described as one of the components in the cirrhosis-associated immune dysfunction syndrome. This syndrome refers to the combination of immune deficiency and exacerbated inflammation that coexist during the course of cirrhosis and relates to the appearance of clinical complications. Since systemic inflammation is often difficult to assess in cirrhosis patients, new objective, reproducible and readily-available markers are needed in order to optimize prognosis and lengthen survival. Thus, surrogate serum markers and clinical parameters of systemic inflammation have been sought to improve disease follow-up and management, especially in decompensated cirrhosis and ACLF. Leukocyte counts (evaluated as total leukocytes, total eosinophils or neutrophil:lymphocyte ratio) and plasma levels of procalcitonin or C-reactive protein have been proposed as prognostic markers, each with advantages and shortcomings. Research and prospective randomized studies that validate these and other markers are clearly warranted.

IGF-1 decreases portal vein endotoxin via regulating intestinal tight junctions and plays a role in attenuating portal hypertension of cirrhotic rats

Background

Intestinal barrier dysfunction is not only the consequence of liver cirrhosis, but also an active participant in the development of liver cirrhosis. Previous studies showed that external administration of insulin-like growth factor 1 (IGF-1) improved intestinal barrier function in liver cirrhosis. However, the mechanism of IGF-1 on intestinal barrier in liver cirrhosis is not fully elucidated. The present study aims to investigate the mechanisms of IGF-1 improving intestinal barrier function via regulating tight junctions in intestines.

Methods

We used carbon tetrachloride induced liver cirrhotic rats to investigate the effect of IGF-1 on intestinal claudin-1 and occludin expressions, serum alanine transaminase (ALT) and aspartate transaminase (AST) levels, severity of liver fibrosis, portal pressures, enterocytic apoptosis and lipopolysaccharides (LPS) levels in portal vein. The changes of IGF-1 in serum during the development of rat liver cirrhosis were also evaluated. Additionally, we assessed the effect of IGF-1 on claudin-1 and occludin expressions, changes of transepithelial electrical resistance (TEER) and apoptosis in Caco-2 cells to confirm in vivo findings.

Results

Serum IGF-1 levels were decreased in the development of rat liver cirrhosis, and external administration of IGF-1 restored serum IGF-1 levels. External administration of IGF-1 reduced serum ALT and AST levels, severity of liver fibrosis, LPS levels in portal vein, enterocytic apoptosis and portal pressure in cirrhotic rats. External administration of IGF-1 increased the expressions of claudin-1 and occludin in enterocytes, and attenuated tight junction dysfunction in intestines of cirrhotic rats. LPS decreased TEER in Caco-2 cell monolayer. LPS also decreased claudin-1 and occludin expressions and increased apoptosis in Caco-2 cells. Furthermore, IGF-1 attenuated the effect of LPS on TEER, claudin-1 expression, occludin expression and apoptosis in Caco-2 cells.

Conclusions

Tight junction dysfunction develops during the development of liver cirrhosis, and endotoxemia will develop subsequently. Correspondingly, increased endotoxin in portal system worsens tight junction dysfunction via decreasing intestinal occludin and claudin-1 expressions and increasing enterocytic apoptosis. Endotoxemia and intestinal barrier dysfunction form a vicious circle. External administration of IGF-1 breaks this vicious circle. Improvement of tight junctions might be one possible mechanism of the restoration of intestinal barrier function mediated by IGF-1.

Infection as a Trigger for Portal Hypertension

BACKGROUND

Microbial infections are a relevant problem for patients with liver cirrhosis. Different types of bacteria are responsible for different kinds of infections: Escherichia coli and Klebsiella pneumoniae are frequently observed in spontaneous bacterial peritonitis or urinary tract infections, and Streptococcus pneumoniae and Mycoplasma pneumoniae in pulmonary infections. Mortality is up to 4-fold higher in infected patients with liver cirrhosis than in patients without infections. Key Messages: Infections in patients with liver cirrhosis are due to three major reasons: bacterial translocation, immune deficiency and an increased incidence of systemic infections. Nonparenchymal liver cells like Kupffer cells, sinusoidal endothelial cells and hepatic stellate cells are the first liver cells to come into contact with microbial products when systemic infection or bacterial translocation occurs. Kupffer cell (KC) activation by Toll-like receptor (TLR) agonists and endothelial sinusoidal dysfunction have been shown to be important mechanisms increasing portal pressure following intraperitoneal lipopolysaccharide pretreatment in cirrhotic rat livers. Reduced intrahepatic vasodilation and increased intrahepatic vasoconstriction are the relevant pathophysiological pathways. Thromboxane A2 and leukotriene (LT) C4/D4 have been identified as important vasoconstrictors. Accordingly, treatment with montelukast to inhibit the cysteinyl-LT1 receptor reduced portal pressure in cirrhotic rat livers. Clinical studies have demonstrated that activation of KCs, estimated by the amount of soluble CD163 in the blood, correlates with the risk for variceal bleeding. Additionally, intestinal decontamination with rifaximin in patients with alcohol-associated liver cirrhosis reduced the portal pressure and the risk for variceal bleeding.

CONCLUSIONS

TLR activation of nonparenchymal liver cells by pathogens results in portal hypertension. This might explain the pathophysiologic correlation between microbial infections and portal hypertension in patients with liver cirrhosis. These findings are the basis for both better risk stratifying and new treatment options, such as specific inhibition of TLR for patients with liver cirrhosis and portal hypertension.

B-cell-associated immune profiles in patients with decompensated cirrhosis

OBJECTIVE

Previous observations on immune dysfunction in decompensated cirrhosis have raised the possibility of B-cell impairment.

METHODS

B-cell subsets in decompensated cirrhotic patients were investigated. Twenty-six decompensated cirrhotic patients and 26 healthy controls were included in this study. The percentages of B-cell subsets, such as mature, memory, immature B cells, and interleukin (IL)-10+-B-cell subpopulations, were measured using fluorescent activated cell sorting. B-cell-associated cytokines (IL-10, IL-21 and IL-4) were determined using an enzyme-linked immunosorbent assay.

RESULTS

The percentage of total B cells and mature B cells increased in patients with decompensated cirrhosis compared to healthy controls. The proportions of memory B cells were significantly lower in the decompensated cirrhosis group than the control group. However, the frequency of immature B cells and the percentage of IL-10-expressing cells that were CD19+, memory, mature, or immature B cells were not significantly different between the two groups. Serum levels of IL-10, IL-21, and IL-4 were significantly lower in the decompensated cirrhosis group compared to the control group.

CONCLUSION

These results indicate significant alterations in peripheral blood B-cell subsets in patients with decompensated cirrhosis. Specifically, a profound reduction of memory B cells was observed in spite of an increase in total B-cell populations in decompensated cirrhotic patients. This implies the underlying mechanisms of impaired immune response in these patients.

Prognostic value of C-reactive protein levels in patients with cirrhosis

I dentifying cirrhosis with a poor short-term prognosis remains crucial for improving the allocation of liver grafts. The purpose of this study was to assess the prognostic value of a model combining the variation of C-reactive protein (CRP) levels within 15 days, the Model for End-Stage Liver Disease (MELD) score, and the presence of comorbidities in patients with decompensated cirrhosis with a Child-Pugh score > B7 and to test the relevance of this model in patients with compensated cirrhosis. We collected data for cirrhotic patients without hepatocellular carcinoma, extrahepatic malignancy, human immunodeficiency virus infection, organ transplantation, seen between January 2010 and December 2011. Multivariate analyses of predictors of 3-month mortality used Cox models adjusted with the age-adjusted Charlson comorbidity index. The prognostic performance [area under receiver operating characteristic curves (AUROCs)] of the 3-variable model was compared to that of the MELD score. The 241 patients who met the inclusion criteria included 109 patients with a Child-Pugh score > B7 who were hospitalized for decompensation. In these patients with severe cases, the 3-month mortality was independently predicted by the MELD score [hazard ratio (HR), 1.10; 95% confidence interval (CI), 1.05-1.14; P < 0.001] and a CRP level > 32 mg/L at the baseline and on day 15 (HR, 2.21; 95% CI, 1.03-4.76; P = 0.042). This model was better than MELD alone (AUROC, 0.789 versus 0.734; P = 0.043). In the whole population with cirrhosis, the 3-month mortality was also predicted by high MELD scores (HR, 1.11; 95% CI, 1.07-1.16; P < 0.001) and a CRP level > 10 mg/L at the baseline and on day 15 (HR, 2.89; 95% CI, 1.29-6.48; P < 0.001), but the AUROCs of the 3-variable model and the MELD score alone were no longer significantly different (0.89 versus 0.88, not significant). In conclusion, prognostic models incorporating variations in CRP predict 3-month mortality in patients with cirrhosis. Such models are particularly relevant for patients with decompensated cirrhosis but provide a limited increase in prediction in comparison with the MELD score in the whole population with cirrhosis.

Two-Stage Revision Arthroplasty for Periprosthetic Hip Infection: Mean Follow-Up of Ten Years

Background. Two-stage revision hip arthroplasty is the gold standard for treatment of patients with chronic periprosthetic joint infection (PJI), but few studies have reported outcomes beyond short-term follow-up. Methods. A total of 155 patients who underwent two-stage revision arthroplasty for chronic PJI in 157 hips were retrospectively enrolled in this study between January 2001 and December 2010. The mean patient age was 57.5 years, the mean prosthetic age was 3.6 years, and the interim interval was 17.8 weeks. These patients were followed up for an average of 9.7 years. Results. At the latest follow-up, 91.7% of the patients were free of infection. The mean Harris hip score improved significantly from 28.3 points before operation to 85.7 points at the latest follow-up. Radiographically, there was aseptic loosening of the stem or acetabular components in 4 patients. In the multivariate survival analysis using a Cox regression model, repeated debridement before final reconstruction, an inadequate interim period, bacteriuria or pyuria, and cirrhosis were found to be the independent risk factors for treatment failure. Conclusion. Our data show that two-stage revision hip arthroplasty provides reliable eradication of infection and durable reconstruction of the joint in patients with PJI caused by a variety of pathogens.

Fecal calprotectin use in inflammatory bowel disease and beyond: A mini-review

Given the number of inflammatory disorders affecting the gastrointestinal tract directly and indirectly, coupled with the considerable overlap with functional disorders, it is evident that more useful noninvasive diagnostic tests are required to aid with diagnosis. If these tests can also have some utility for individual patient follow-up in terms of disease activity and response to treatment, as well as providing forewarning of disease relapse, it would be extremely useful information for the clinician. One recently described test that may fulfill several of these attributes is based on leakage of a mononuclear cell cytoplasmic protein, calprotectin, along the intestinal tract, which can then be quantified in feces. This has been used to distinguish patients exhibiting symptoms of irritable bowel syndrome from patients with inflammatory bowel disease, with a measure of success greater than with currently used techniques. The present article summarizes the experience with this test used in inflammatory bowel disease, as well as a variety of gastrointestinal disorders.

Interleukin-1 receptor antagonist correlates with hepatic venous pressure gradient and predicts occurrence of overall complications and bacterial infections in patients with cirrhosis

AIM

The plasma levels of interleukin (IL)-1α, IL-1β and IL-1 receptor antagonist (IL-1Ra) are increased in cirrhotic patients. We aimed to investigate whether these cytokines correlate with hepatic venous pressure gradient (HVPG), the severity of liver cirrhosis and complications of cirrhosis.

METHODS

Sixty-three cirrhotic patients that underwent hemodynamic studies in Taipei Veterans General hospital were enrolled retrospectively. Plasma levels of IL-1α, IL-1β, IL-1Ra and endotoxin were assessed by enzyme-linked immunosorbent assay. Plasma obtained from 11 healthy subjects served as normal controls.

RESULTS

Plasma levels of IL-1α, IL-1β and IL-1Ra were increased in cirrhotic patients compared with controls. IL-1Ra levels significantly correlated with plasma endotoxin levels, Child-Pugh scores, Model of End-Stage Liver Disease (MELD) scores and HVPG. On multivariate analysis, higher IL-1Ra levels (≥760 pg/mL) predicted the occurrence of portal hypertension-related complications and the development of bacterial infections independently of the MELD scores and portal pressure. Furthermore, higher IL-1Ra levels also predicted the survival in patients without hepatocellular carcinoma.

CONCLUSION

The plasma IL-1Ra level correlates with HVPG. Additionally, it may predict the occurrence of portal hypertension-related complications and bacterial infections in cirrhotic patients and the survival in patients without hepatocellular carcinoma.

Alcohol and HCV: implications for liver cancer

Liver cancers are one of the deadliest known malignancies which are increasingly becoming a major public health problem in both developed and developing countries. Overwhelming evidence suggests a strong role of infection with hepatitis B and C virus (HBV and HCV), alcohol abuse, as well as metabolic diseases such as obesity and diabetes either individually or synergistically to cause or exacerbate the development of liver cancers. Although numerous etiologic mechanisms for liver cancer development have been advanced and well characterized, the lack of definite curative treatments means that gaps in knowledge still exist in identifying key molecular mechanisms and pathways in the pathophysiology of liver cancers. Given the limited success with current therapies and preventive strategies against liver cancer, there is an urgent need to identify new therapeutic options for patients. Targeting HCV and or alcohol-induced signal transduction, or virus-host protein interactions may offer novel therapies for liver cancer. This review summarizes current knowledge on the mechanistic development of liver cancer associated with HCV infection and alcohol abuse as well as highlights potential novel therapeutic strategies.

Association of markers of bacterial translocation with immune activation in decompensated cirrhosis

BACKGROUND

Bacterial translocation (BT) may cause infections, in particular, spontaneous bacterial peritonitis (SBP). In the absence of overt infection, BT may further stimulate the immune system and contribute to haemodynamic alterations and complications. Bacterial DNA (bDNA) is claimed to be a promising surrogate marker for BT, although its clinical relevance has been questioned.

MATERIALS AND METHODS

In 38 cirrhotic patients with and without SBP, bDNA in blood and ascites were assessed by 16S rDNA quantitative PCR. Levels of lipopolysaccharide-binding protein in plasma and highly sensitive C-reactive protein, tumour necrosis factor-α, soluble urokinase plasminogen activating receptor, interleukin-6, interleukin 8, interferon-γ inducible protein-10 and vascular endothelial growth factor in plasma and ascites were measured by multiplex cytokine and ELISA assays.

RESULTS

In patients without signs of SBP or positive cultures, we found a high frequency of bDNA but low concordance of bDNA between blood and ascites. Markers of inflammation were not significantly different between blood bDNA-positive (22%), ascites bDNA-positive (52%), and bDNA-negative patients. The 16S rDNA PCR failed to show bDNA in two out of six samples with SBP. Sequencing of positive samples did not determine the source of bDNA.

CONCLUSION

bDNA as assessed by this PCR method was largely unrelated to markers of inflammation and does not seem to be of clinical value in the diagnosis of SBP. According to our results, bDNA is not a reliable marker of BT.

A farnesoid X receptor polymorphism predisposes to spontaneous bacterial peritonitis

BACKGROUND

In mice, the farnesoid X receptor is involved in bacterial translocation, which can result in spontaneous bacterial peritonitis in patients with cirrhosis. We investigated if polymorphisms in the farnesoid X receptor gene influence the risk for spontaneous bacterial peritonitis.

METHODS

Laboratory and clinical data of 293 cirrhotic patients with ascites and 226 healthy controls were prospectively collected. The rs56163822, rs11110390 and rs12313471 polymorphisms of the farnesoid X receptor were determined.

RESULTS

115 (39%) patients had spontaneous bacterial peritonitis. Distribution of all farnesoid X receptor genotypes matched the Hardy-Weinberg equilibrium. Patients with spontaneous bacterial peritonitis had a higher frequency of the rs56163822 GT genotype (7.0%) than patients without (1.7%, OR=4.4, p=0.02). This genotype was confirmed as predictor of spontaneous bacterial peritonitis by binary logistic regression analysis (OR=6.8, p=0.018).

CONCLUSION

The farnesoid X receptor rs56163822 GT genotype increases the risk for spontaneous bacterial peritonitis in cirrhotic patients with ascites.

Intensive care unit management of patients with liver failure

Acute liver failure (ALF) and acute-on-chronic liver failure (ACLF) usually mandate management within an intensive care unit (ICU). Even though the conditions bear some similarities, precipitating causes, and systemic complications management practices differ. Although early identification of ALF and ACLF, improvements in ICU management, and the widespread availability of liver transplantation have improved mortality, optimal management practices have not been defined. This article summarizes current ICU management practices and identifies areas of management that require further study.

Functional gene arrays-based analysis of fecal microbiomes in patients with liver cirrhosis

Background

Human gut microbiota plays an important role in the pathogenesis of cirrhosis complications. Although the phylogenetic diversity of intestinal microbiota in patients with liver cirrhosis has been examined in several studies, little is known about their functional composition and structure.

Results

To characterize the functional gene diversity of the gut microbiome in cirrhotic patients, we recruited a total of 42 individuals, 12 alcoholic cirrhosis patients, 18 hepatitis B virus (HBV)-related cirrhosis patients, and 12 normal controls. We determined the functional structure of these samples using a specific functional gene array, which is a combination of GeoChip for monitoring biogeochemical processes and HuMiChip specifically designed for analyzing human microbiomes. Our experimental data showed that the microbial community functional composition and structure were dramatically distinctive in the alcoholic cirrhosis. Various microbial functional genes involved in organic remediation, stress response, antibiotic resistance, metal resistance, and virulence were highly enriched in the alcoholic cirrhosis group compared to the control group and HBV-related cirrhosis group. Cirrhosis may have distinct influences on metabolic potential of fecal microbial communities. The abundance of functional genes relevant to nutrient metabolism, including amino acid metabolism, lipid metabolism, nucleotide metabolism, and isoprenoid biosynthesis, were significantly decreased in both alcoholic cirrhosis group and HBV-related cirrhosis group. Significant correlations were observed between functional gene abundances and Child-Pugh scores, such as those encoding aspartate-ammonia ligase, transaldolase, adenylosuccinate synthetase and IMP dehydrogenase.

Conclusions

Functional gene array was utilized to study the gut microbiome in alcoholic and HBV-related cirrhosis patients and controls in this study. Our array data indicated that the functional composition of fecal microbiomes was heavily influenced by cirrhosis, especially by alcoholic cirrhosis. This study provides new insights into the functional potentials and activity of gut microbiota in cirrhotic patients with different etiologies.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-753) contains supplementary material, which is available to authorized users.

Vaccinations in older adults with gastrointestinal diseases

Vaccines play a key role in the prevention of illness in the elderly, are cost effective, and generally safe. Hepatitis C, cirrhosis, autoimmune hepatitis, and inflammatory bowel disease are more prevalent than ever among older adults. Along with an age-related decline in immune system function (immunosenescence), these diseases make elderly individuals more susceptible to infections and more likely to experience a poor outcome relative to their younger counterparts. Vaccinations also appear to be less effective in the elderly, warranting research into different vaccination strategies such as booster vaccines, higher doses of vaccine, and measurement of antibody titers to guide vaccination.

Alterations of the human gut microbiome in liver cirrhosis

Liver cirrhosis occurs as a consequence of many chronic liver diseases that are prevalent worldwide. Here we characterize the gut microbiome in liver cirrhosis by comparing 98 patients and 83 healthy control individuals. We build a reference gene set for the cohort containing 2.69 million genes, 36.1% of which are novel. Quantitative metagenomics reveals 75,245 genes that differ in abundance between the patients and healthy individuals (false discovery rate < 0.0001) and can be grouped into 66 clusters representing cognate bacterial species; 28 are enriched in patients and 38 in control individuals. Most (54%) of the patient-enriched, taxonomically assigned species are of buccal origin, suggesting an invasion of the gut from the mouth in liver cirrhosis. Biomarkers specific to liver cirrhosis at gene and function levels are revealed by a comparison with those for type 2 diabetes and inflammatory bowel disease. On the basis of only 15 biomarkers, a highly accurate patient discrimination index is created and validated on an independent cohort. Thus microbiota-targeted biomarkers may be a powerful tool for diagnosis of different diseases.

A multicenter prospective study of infections related morbidity and mortality in cirrhosis of liver

BACKGROUND AND AIMS

Infections are a common and serious complication among patients with cirrhosis. We assessed the epidemiology, risk factors, and clinical consequences of bacterial infections in cirrhotic patients.

METHODS

In this multicenter prospective study, all patients with cirrhosis of liver with different infections were analyzed. Infections were classified as community-acquired (CA), healthcare-associated (HCA), or hospital-acquired (HA). Site of infection and characteristics of bacteria were recorded; effect on liver function and 30-day survival were evaluated.

RESULTS

One hundred and six out of 420 (25 %) patients with cirrhosis of liver had infection. Infection rate among indoor patients was 37.5 % (92/245) and among outdoor patients was 8 % (14/175). Out of 106 patients, CA, HCA, and HA were seen in 19.8 %, 50 %, and 30.2 %, respectively. Spontaneous bacterial peritonitis (31.1 %), urinary tract infections (22.6 %), and pneumonia and cellulitis (11.3 % each) were common infections. Gram-negative bacteria (54 %) were more common than Gram-positive cocci (46 %). Multidrug resistant (MDR) organisms were seen in 41.7 % of patients. Most of the MDR organisms were seen in HCA and HA patients. The degree of liver impairment was significantly more severe in patients with infection. Independent predictor of infection was high Child-Turcott-Pugh (CTP) class (p = 0.006, Child B vs. A (odds ratio (OR) 3.04 95 % CI = 1.63 to 5.68) and Child C vs. A (OR 4.17 95 % CI = 2.12 to 8.19). Overall in-hospital mortality was 7.6 %. Patients with infection had increased mortality at 30-day follow up compared to those without infection (23.5 % vs. 2.2 %; p<0.001).

CONCLUSIONS

Infections are one of the important causes of morbidity and mortality in patients with cirrhosis of liver. The most frequent infections are HCA and HA. Infection predisposes to deterioration of liver function and increases mortality. Cirrhotic patients should be monitored closely for infections especially those with Child class B and C.

Protective effect of Bifidobacterium pseudocatenulatum CECT7765 against induced bacterial antigen translocation in experimental cirrhosis

BACKGROUND & AIMS

Intervention in the gut ecosystem is considered as a potential strategy to treat liver diseases and their complications. We have evaluated the effects of Bifidobacterium pseudocatenulatum CECT7765 on bacterial translocation and the liver status in experimental cirrhosis.

ANIMALS & METHODS

Liver damage was induced in Balb/c mice by weight-controlled oral administration of carbon tetrachloride. Laparotomies were performed at week 12. One week prior to laparotomy, animals received B. pseudocatenulatum CECT7765 (10(9) cfu/daily) or placebo intragastrically. All animals received Escherichia coli (10(7) cfu/single dose) intragastrically 24 hours before laparotomy. A group of naïve non-treated animals was included as control. Liver tissue specimens, mesenteric lymph nodes, intestinal content and blood were collected. Liver histology, profibrogenic genes expression, bacterial DNA translocation, serum endotoxaemia and liver cytokine levels were measured.

RESULTS

Bifidobacterium pseudocatenulatum CECT7765 showed no significant effect on structural liver damage, as determined by histological evaluation, alpha-smooth muscle actin distribution, profibrogenic gene expression levels, total hydroxyproline levels and malon dialdehyde production compared with mice receiving placebo. Interestingly, bacterial DNA translocation and serum endotoxin levels were significantly decreased in mice receiving the Bifidobacterium strain compared with placebo. Gut barrier integrity markers were up-regulated in mice receiving B. pseudocatenulatum CECT7765 and quantitatively correlated with intestinal gene copy numbers of the bifidobacterial strain. Gene expression levels of several anti-inflammatory mediators were also increased in mice receiving B. pseudocatenulatum CECT7765 compared with placebo.

CONCLUSION

Oral administration of B. pseudocatenulatum CECT7765 is associated with improved gut barrier integrity and shows a beneficial effect against induced bacterial antigen translocation in the CCl4 -model of cirrhosis.

Liver cirrhosis as a real risk factor for necrotising fasciitis: a three-year population-based follow-up study

INTRODUCTION

Necrotising fasciitis (NF) is often found in patients with diabetes mellitus, chronic renal failure, alcoholism, malignancy or liver cirrhosis. However, it remains unknown whether liver cirrhosis is an independent risk factor for the occurrence of NF. This study aimed to determine whether liver cirrhosis is an independent risk factor for the occurrence of NF, and to identify the relationship between severity of liver cirrhosis and occurrence of NF.

METHODS

The National Health Insurance Research Database, maintained by Taiwan's National Health Insurance programme, was retrospectively analysed, and the hospitalisation data of 40,802 cirrhotic patients and 40,865 randomly selected, age‑ and gender‑matched non‑cirrhotic control patients was collected. The medical records of all patients were individually followed for a three‑year period from the patients' first hospitalisation in 2004.

RESULTS

During the three‑year follow‑up period, there were 299 (0.7%) cirrhotic patients with NF and 160 (0.4%) non‑cirrhotic patients with NF. Cox regression analysis showed that liver cirrhosis was a risk factor for the occurrence of NF during the study period (hazard ratio 1.982; p < 0.001). Among cirrhotic patients, those with complicated liver cirrhosis had a higher risk for the occurrence of NF than patients with non‑complicated liver cirrhosis (hazard ratio 1.320; p = 0.028).

CONCLUSION

Cirrhotic patients had a higher risk for the occurrence of NF than non‑cirrhotic patients, and the risk for NF was especially high among patients with complicated liver cirrhosis.

Acute-on-chronic liver failure: a review

There is no universally accepted definition of acute-on-chronic liver failure; however, it is recognized as an entity characterized by decompensation from an underlying chronic liver disease associated with organ failure that conveys high short-term mortality, with alcoholism and infection being the most frequent precipitating events. The pathophysiology involves inflammatory processes associated with a trigger factor in susceptible individuals (related to altered immunity in the cirrhotic population). This review addresses the different definitions developed by leading research groups, epidemiological and pathophysiological aspects, and the latest treatments for this entity.

Application of qualitative and quantitative real-time PCR, direct sequencing, and terminal restriction fragment length polymorphism analysis for detection and identification of polymicrobial 16S rRNA genes in ascites

Qualitative and quantitative 16S rRNA gene-based real-time PCR and direct sequencing were applied for rapid detection and identification of bacterial DNA (bactDNA) in 356 ascites samples. bactDNA was detected in 35% of samples, with a mean of 3.24 log copies ml(-1). Direct sequencing of PCR products revealed 62% mixed chromatograms predominantly belonging to Gram-positive bacteria. Terminal restriction fragment length polymorphism (T-RFLP) results of a sample subset confirmed sequence data showing polymicrobial DNA contents in 67% of bactDNA-positive ascites samples.

Laboratory diagnostics of spontaneous bacterial peritonitis

The term peritonitis indicates an inflammatory process involving the peritoneum that is most frequently infectious in nature. Primary or spontaneous bacterial peritonitis (SBP) typically occurs when a bacterial infection spreads to the peritoneum across the gut wall or mesenteric lymphatics or, less frequently, from hematogenous transmission in combination with impaired immune system and in absence of an identified intra-abdominal source of infection or malignancy. The clinical presentation of SBP is variable. The condition may manifest as a relatively insidious colonization, without signs and symptoms, or may suddenly occur as a septic syndrome. Laboratory diagnostics play a pivotal role for timely and appropriate management of patients with bacterial peritonitis. It is now clearly established that polymorphonuclear leukocyte (PMN) in peritoneal fluid is the mainstay for the diagnosis, whereas the role of additional biochemical tests is rather controversial. Recent evidence also suggests that automatic cell counting in peritoneal fluid may be a reliable approach for early screening of patients. According to available clinical and laboratory data, we have developed a tentative algorithm for efficient diagnosis of SBP, which is based on a reasonable integration between optimization of human/economical resources and gradually increasing use of invasive and expensive testing. The proposed strategy entails, in sequential steps, serum procalcitonin testing, automated cell count in peritoneal fluid, manual cell count in peritoneal fluid, peritoneal fluid culture and bacterial DNA testing in peritoneal fluid.

Antibiotics Protect against Septic Shock in Mice Administered β-Glucan and Indomethacin

We have developed an animal model of sepsis in mice by repeatedly administering beta-glucan, a biological response modifier, and indomethacin (IND), a nonsteroidal anti-inflammatory drug. The combination of these drugs induced bacteremia by translocation of the enterobacterial flora, resulting in increasing the number of activated leukocytes, and inducing hyper cytokinemia. In the present study, we examined the effect of antibiotics on beta-glucan and IND-induced septic shock. Treatment with antibiotics inhibited microbial translocation, inhibited contraction of the colon, reduced lipopolysaccharides (LPS)-elicited production of TNF-alpha and IL-6, and finally prolonged survival. However, the efficacy of antibiotics treatment was limited in mice administered IND orally. These findings strongly suggested that the antibiotics controlled the gut-associated action of IND and reduced various symptoms accompanying sepsis.

Intestinal epithelial barrier function in liver cirrhosis: an extensive review of the literature

Recent evidence suggests that translocation of bacteria and bacterial products, such as endotoxin from the intestinal lumen into the systemic circulation is a contributing factor in the pathogenesis of chronic liver diseases and the development of complications in cirrhosis. In addition to alterations in the intestinal microbiota and immune system, dysfunction of the intestinal epithelial barrier may be an important factor facilitating bacterial translocation. This review aims to provide an overview of the current evidence of intestinal epithelial barrier dysfunction in human chronic liver diseases and cirrhosis, and to discuss possible contributing factors and mechanisms. Data suggest the presence of intestinal epithelial barrier dysfunction in patients with chronic liver diseases, but are more convincing in patients with cirrhosis, especially in those with complications. The barrier dysfunction can result from both direct and indirect effects of aetiological factors, such as alcohol and obesity, which can cause chronic liver diseases and ultimately cirrhosis. On the other hand characteristics of cirrhosis itself, including portal hypertension, alterations in the intestinal microbiota, inflammation and oxidative stress can affect barrier function of both small and large intestine and may contribute to the development of complications. In conclusion, there are indications for intestinal epithelial barrier dysfunction in patients with chronic liver diseases and especially in patients with cirrhosis, which can be caused by various factors affecting both the small and large intestine.

No difference in portal and hepatic venous bacterial DNA in patients with cirrhosis undergoing transjugular intrahepatic portosystemic shunt insertion

BACKGROUND

Bacterial translocation (BT) with immune activation may lead to hemodynamical alterations and poor outcomes in patients with cirrhosis.

AIMS

We investigated bacterial DNA (bDNA), a marker of BT, and its relation to portal pressure and markers of inflammation in the portal and hepatic veins in patients with cirrhosis undergoing TIPS insertion.

METHODS

We analysed plasma for bDNA and markers of inflammation in 28 patients [median portal pressure gradient 15 (11-19) mmHg] during TIPS treatment for refractory ascites (n = 19) or acute variceal bleeding (n = 9). Advanced cirrhosis was present in the majority [Child-Pugh class (A/B/C): 1/14/13], and most often caused by alcohol (n = 21).

RESULTS

bDNA was detectable in one or both samples in 16 of 28 patients (57%). bDNA was present in 39% of the samples from the portal vein vs 43% of the samples in the hepatic vein (P = 0.126). Antibiotics had no effect on bDNA or markers of inflammation. Markers of inflammation did not differ between the hepatic and portal veins with the exceptions of soluble urokinase plasminogen activating receptor (suPAR) and vascular endothelial growth factor (VEGF), both higher in the hepatic vein (P = 0.031 and 0.003 respectively).

CONCLUSIONS

No transhepatic gradient of bDNA was evident, suggesting that no major hepatic elimination of bDNA occurs in advanced liver disease. bDNA, in contrast to previous reports was largely unrelated to a panel of markers of inflammation and without relation to portal pressure.

Acute phase proteins for the diagnosis of bacterial infection and prediction of mortality in acute complications of cirrhosis

INTRODUCTION

Bacterial infection is a frequent complication in patients with decompensated liver cirrhosis and is related to high mortality rates during follow-up of these individuals. We sought to evaluate the diagnostic value of C-reactive protein (CRP) and procalcitonin (PCT) in diagnosing infection and to investigate the relationship between these biomarkers and mortality after hospital admission.

MATERIAL AND METHODS

Prospective study that included cirrhotic patients admitted to the hospital due to complications of the disease. The diagnostic accuracy of CRP and PCT for the diagnosis of infection was evaluated by estimating the sensitivity and specificity and by measuring the area under the receiver operating characteristics curve (AUROC).

RESULTS

A total of 64 patients and 81 hospitalizations were analyzed during the study. The mean age was 54.31 ± 11.87 years with male predominance (68.8%). Significantly higher median CRP and PCT levels were observed among infected patients (P < 0.001). The AUROC of CRP and PCT for the diagnosis of infection were 0.835 ± 0.052 and 0.860 ± 0.047, respectively (P = 0.273). CRP levels > 29.5 exhibited sensitivity of 82% and specificity of 81% for the diagnosis of bacterial infection. Similarly, PCT levels > 1.10 showed sensitivity of 67% and specificity of 90%. Significantly higher levels of CRP (P = 0.026) and PCT (P = 0.001) were observed among those who died within three months after admission.

CONCLUSION

CRP and PCT were reliable markers of bacterial infection in subjects admitted due to complications of liver cirrhosis and higher levels of these tests are related to short-term mortality in those patients.

Non-selective betablocker therapy decreases intestinal permeability and serum levels of LBP and IL-6 in patients with cirrhosis

BACKGROUND & AIMS

We evaluated the gastrointestinal permeability and bacterial translocation in cirrhotic patients with portal hypertension (PHT) prior to and after non-selective betablocker (NSBB) treatment.

METHODS

Hepatic venous pressure gradient (HVPG) was measured prior to and under NSBB treatment. Gastroduodenal and intestinal permeability was assessed by the sucrose-lactulose-mannitol (SLM) test. Anti-gliadin and anti-endomysial antibodies were measured. Levels of LPS-binding protein (LBP) and interleukin-6 (IL-6) were quantified by ELISA, and NOD2 and toll-like receptor 2 (TLR2) polymorphisms were genotyped.

RESULTS

Fifty cirrhotics were included (72% male, 18% ascites, 60% alcoholic etiology). Abnormal gastroduodenal and intestinal permeability was found in 72% and 59% of patients, respectively. Patients with severe portal hypertension (HVPG ≥20 mm Hg; n=35) had increased markers of gastroduodenal/intestinal permeability (urine sucrose levels p=0.049; sucrose/mannitol ratios p=0.007; intestinal permeability indices p=0.002), and bacterial translocation (LBP p=0.002; IL-6 p=0.025) than patients with HVPG <20 mm Hg. A substantial portion of patients showed elevated levels of anti-gliadin antibodies (IgA: 60%, IgG: 34%) whereas no anti-endomysial antibodies were detected. A significant correlation of portal pressure (i.e., HVPG) with all markers of gastroduodenal/intestinal permeability and with LBP and IL-6 levels was observed. NOD2 and TLR2 risk variants were associated with abnormal intestinal permeability and elevated markers of bacterial translocation. At follow-up HVPG measurements under NSBB, we found an amelioration of gastroduodenal/intestinal permeability and a decrease of bacterial translocation (LBP - 16% p=0.018; IL-6 - 41% p<0.0001) levels, which was not limited to hemodynamic responders. Abnormal SLM test results and higher LBP/IL-6 levels were associated with a higher risk of variceal bleeding during follow-up but not with mortality.

CONCLUSIONS

Abnormal gastroduodenal/intestinal permeability, anti-gliadin antibodies, and bacterial translocation are common findings in cirrhotic patients and are correlated with the degree of portal hypertension. NSBB treatment ameliorates gastroduodenal/intestinal permeability and reduces bacterial translocation partially independent of their hemodynamic effects on portal pressure, which may contribute to a reduced risk of variceal bleeding.

Intestinal permeability and complications in liver cirrhosis: A prospective cohort study

AIM

  Increased intestinal permeability (IP) has been implicated as an important factor for bacterial translocation (BT), leading to bacteremia and endotoxemia, resulting in various septic complications, variceal bleeding (VB), hepatic encephalopathy (HE), hepatorenal syndrome (HRS) and death in patients with liver cirrhosis (LC). This study was planned to assess IP in patients with LC and follow them for the occurrence of complications.

METHODS

  Patients with Child B and C cirrhosis without a history of disease-related complications were followed up for 6 months. IP was measured by lactulose and mannitol excretion ratio (LMR) in patients and 50 healthy controls (HC). Serum endotoxin levels were also assessed in 48 patients and 20 HC.

RESULTS

  Eighty patients (74 male), 41 (51.3%) Child B and 56 (70%) Child C, with a mean age of 40.7 ± 9.8 years were enrolled. IP was increased in 28 (35%) patients. LMR of patients was higher than HC (patients vs HC = 0.0238 [0.0010-1.557] vs 0.0166 [0.0018-0.720]; P = 0.007]. No significant difference was seen in the LMR of patients among various Child classes and etiologies. Serum endotoxin levels (GMU/mL) were higher in patients than HC (patients vs HC = 1.42 [0.68-2.13] vs 0.994 [0.067-1.382]; P = 0.001), but comparable between patients with abnormal and normal IP. At follow up, there was no significant difference in the incidence of complications like spontaneous bacterial peritonitis, HRS, VB, HE and death between patients with abnormal and normal IP.

CONCLUSION

  IP was increased in 35% of patients with LC; however, it was not associated with a higher incidence of disease-related complications.

Chronic immune activation in common variable immunodeficiency (CVID) is associated with elevated serum levels of soluble CD14 and CD25 but not endotoxaemia

Common variable immunodeficiency (CVID), the most frequent symptomatic immunoglobulin primary immunodeficiency, is associated with chronic T cell activation and reduced frequency of CD4(+) T cells. The underlying cause of immune activation in CVID is unknown. Microbial translocation indicated by elevated serum levels of lipopolysaccharide and soluble CD14 (sCD14) has been linked previously to systemic immune activation in human immunodeficiency virus/acquired immune deficiency syndrome (HIV-1/AIDS), alcoholic cirrhosis and other conditions. To address the mechanisms of chronic immune activation in CVID, we performed a detailed analysis of immune cell populations and serum levels of sCD14, soluble CD25 (sCD25), lipopolysaccharide and markers of liver function in 35 patients with CVID, 53 patients with selective immunoglobulin (Ig)A deficiency (IgAD) and 63 control healthy subjects. In CVID subjects, the concentration of serum sCD14 was increased significantly and correlated with the level of sCD25, C-reactive protein and the extent of T cell activation. Importantly, no increase in serum lipopolysaccharide concentration was observed in patients with CVID or IgAD. Collectively, the data presented suggest that chronic T cell activation in CVID is associated with elevated levels of sCD14 and sCD25, but not with systemic endotoxaemia, and suggest involvement of lipopolysaccharide-independent mechanisms of induction of sCD14 production.

The role of gut-liver axis in the pathogenesis of liver cirrhosis and portal hypertension

Because of the anatomical position and its unique vascular system, the liver is susceptible to the exposure to the microbial products from the gut. Although large amount of microbes colonize in the gut, translocation of the microbes or microbial products into the liver and systemic circulation is prevented by gut epithelial barrier function and cleansing and detoxifying functions of the liver in healthy subjects. However, when the intestinal barrier function is disrupted, large amount of bacterial products can enter into the liver and systemic circulation and induce inflammation through their receptors. Nowadays, there have been various reports suggesting the role of gut flora and bacterial translocation in the pathogenesis of chronic liver disease and portal hypertension. This review summarizes the current knowledge about bacterial translocation and its contribution to the pathogenesis of chronic liver diseases and portal hypertension.

Acute febrile illness in cirrhosis – thinking beyond spontaneous bacterial peritonitis!

Summary

The aim of this study was to look at the aetiological factors presenting as acute febrile illness in cirrhotic patients. The study group included all cirrhotic patients admitted as inpatients between January and December 2011 with a history of fever of less than seven days duration. Detailed history, clinical examination and investigations, as required, were noted. The data collected were analysed. A total of 42 patients formed the study group. The male-to-female ratio was 9.5:1. The mean age at presentation was 45.09 years (24 –77 years). The aetiological factors for fever were: spontaneous bacterial peritonitis (20), lower respiratory tract infection (8), urinary tract infection (6), lower limb cellulitis (4), acute cholecystitis (2) and malaria (2). The mean MELD (model for end-stage liver disease) score at presentation was 20.4. Three patients with spontaneous bacterial peritonitis (SBP) and a mean MELD score of 31 died during the hospital admission. Febrile illness in cirrhosis is attributable to multiple causes. Outcome is dependent on the severity of underlying liver disease.

Microbial translocation in chronic liver diseases

The intestinal microflora is not only involved in the digestion of nutrients, but also in local immunity, forming a barrier against pathogenic microorganisms. The derangement of the gut microflora may lead to microbial translocation, defined as the passage of viable microorganisms or bacterial products (i.e., LPS, lipopeptides) from the intestinal lumen to the mesenteric lymph nodes and other extraintestinal sites. The most recent evidence suggests that microbial translocation (MT) may occur not only in cirrhosis, but also in the early stage of several liver diseases, including alcoholic hepatopathy and nonalcoholic fatty liver disease. Different mechanisms, such as small intestinal bacterial overgrowth, increased permeability of intestinal mucosa, and impaired immunity, may favor MT. Furthermore, MT has been implicated in the pathogenesis of the complications of cirrhosis, which are a significant cause of morbidity and mortality in cirrhotic subjects. Therapeutic strategies aiming at modulating the gut microflora and reducing MT have focused on antibiotic-based options, such as selective intestinal decontamination, and nonantibiotic-based options, such as prokinetics and probiotics. In particular, probiotics may represent an attractive strategy, even though the promising results of experimental models and limited clinical studies need to be confirmed in larger randomized trials.

Evaluation of different therapeutic approaches for spontaneous bacterial peritonitis

BACKGROUND AND STUDY AIMS

Spontaneous bacterial peritonitis (SBP) is a significant cause of mortality in cirrhosis. Reducing toxic burden of infected ascitic fluid through paracentesis needs further studies as adjunctive therapy of SBP. We aimed to evaluate different therapies for SBP.

PATIENTS AND METHODS

Thirty-six cirrhotic ascitic patients with SBP were examined and classified according to treatment modality (5-7 days) into: Group A received cefotaxime, group B received cefotaxime and albumin 1.5 g/kg body weight within 6h of SBP being diagnosed and 1g/kg body weight on day 3, group C received cefotaxime and paracentesis with volume dependent albumin infusion. Control group of 12 cirrhotic ascitic patients free from SBP were included. Routine laboratory tests, ascitic fluid analysis for leucocytes and culture were done, inflammatory mediators such as nitric oxide and tumour necrosis factor alpha were measured in serum and ascitic fluid. Duplex-Doppler assessment of portal flow volume and renal resistive index, Echocardiography to measure end diastolic and end systolic volumes, stroke volume and cardiac output were done. Tests were carried out before and after therapy.

RESULTS

Treatment response was assessed by, cardiac haemodynamics, portal and renal flow and NO and TNF. All studied parameters; laboratory, cardiac, Doppler exhibited a significant improvement in group B in contrast to the other groups as demonstrated by post therapy reduction of (blood and ascitic fluid WBCs & PNLS, serum and ascitic NO & TNF and renal resistive index), elevation of (serum albumin and portal flow volume) and improvement of cardiac haemodynamic.

CONCLUSION

Treatment of spontaneous bacterial peritonitis by cefotaxime and body weight based albumin infusion gave most favourable results compared to other regimens. Postulation of removing toxic burden through paracentesis has not been confirmed.

Rifaximin improves systemic hemodynamics and renal function in patients with alcohol-related cirrhosis and ascites

Circulating levels of endotoxin, interleukin (IL)-6, and tumor necrosis factor (TNF)-α increase with intestinal bacterial overgrowth and translocation, and are believed to be involved in the pathogenesis of hyperdynamic circulatory syndrome and functional renal failure in patients with advanced cirrhosis. We investigated the effects of the antibiotic rifaximin on systemic hemodynamics and renal function in patients with alcohol-related cirrhosis and ascites. We measured mean arterial pressure, cardiac output (CO) by Doppler ultrasound, systemic vascular resistance (as the ratio of mean arterial pressure:CO), plasma renin activity, levels of plasma aldosterone, the glomerular filtration rate by plasma clearance of technetium-99m-DTPA, natriuresis, levels of plasma endotoxin, and serum levels of IL-6 and TNF-α in 13 patients at baseline and after 4 weeks of treatment with rifaximin. Rifaximin treatment significantly reduced CO and significantly increased systemic vascular resistance, in association with a significant decrease in plasma rennin activity. The therapy also significantly increased the glomerular filtration rate and natriuresis while reducing levels of endotoxin, IL-6, and TNF-α. Intestinal decontamination with rifaximin improved systemic hemodynamics and renal function in patients with advanced cirrhosis.

High-sensitivity C-reactive protein levels predict survival and are related to haemodynamics in alcoholic cirrhosis

OBJECTIVES

Inflammation may be implicated in the haemodynamic deterioration and in the development of complications in patients with cirrhosis. High-sensitivity C-reactive protein (hsCRP) is a marker of low-grade inflammation, and predicts outcomes in patients at risk of ischaemic heart disease. Proinflammatory cytokines reflect immune activation and have been found to be elevated in cirrhosis. We investigated a possible association between markers of inflammation and splanchnic and systemic haemodynamics, complications and survival in patients with cirrhosis.

METHODS

In 45 stable patients with cirrhosis on the basis of alcohol consumption, we measured hsCRP, as well as monocyte chemoattractant protein-1, tumour necrosis factor-α, interleukin-6, interleukin-8 and vascular endothelial growth factor in patients and in 12 healthy controls. Systemic and splanchnic haemodynamics were investigated in patients.

RESULTS

hsCRP levels were significantly higher in patients compared with controls (P<0.05) and the highest in patients belonging to Child-Pugh class C. hsCRP levels correlated with markers of liver dysfunction and with the hepatic venous pressure gradient (r=0.48, P<0.001). hsCRP values above the median level of 5.3 mg/l were associated with a highly increased mortality (P=0.001). Model for End-Stage Liver Disease score (P=0.01) and hsCRP (P<0.05) provided independent prognostic information. Cytokines had no discernible value in predicting survival.

CONCLUSION

hsCRP is elevated in patients with cirrhosis and is associated with portal hypertension and decreased survival. hsCRP is a promising prognostic marker in cirrhosis, which may improve the selection of candidates for liver transplantation.

Hepatic encephalopathy

Hepatic encephalopathy (HE) represents a continuum of transient and reversible neurologic and psychiatric dysfunction. It is a reversible state of impaired cognitive function or altered consciousness in patients with liver disease or portosystemic shunting. Over the last several years, high-quality studies have been conducted on various pharmacologic therapies for HE; as more data emerge, it is hoped that HE will become a more easily treated complication of decompensated liver disease. In the interim, it is important that physicians continue to screen for minimal HE and treat patients early in addition to continuing to provide current treatments of overt HE.

Intestinal bacterial translocation in rats with cirrhosis is related to compromised Paneth cell antimicrobial host defense

Liver cirrhosis is associated with bacterial translocation (BT) and endotoxemia. Most translocating bacteria belong to the common intestinal microbiota, suggesting a breakdown of intestinal barrier function. We hypothesized that diminished mucosal antimicrobial host defense could predispose to BT. Two rodent models of portal hypertension with increased BT were used, CCl(4)-induced ascitic cirrhosis and 2-day portal vein-ligated (PVL) animals. BT was assessed by standard microbiological techniques on mesenteric lymph nodes. Total RNA was isolated systematically throughout the intestinal tract, and expression of Paneth cell α-cryptdins and β-defensins was determined by real-time quantitative polymerase chain reaction (qPCR). To determine functional consequences, mucosal antimicrobial activity was assessed with a fluorescence-activated cell sorting assay. BT was detectable in 40% of rats with cirrhosis. Compared with the group without BT, these animals exhibited diminished intestinal Paneth cell α-cryptdin 5 and 7 expression. In contrast, PVL was associated with BT in all animals but did not affect antimicrobial peptides. The decrease in Paneth cell antimicrobials was most pronounced in the ileum and the coecum. Other antimicrobials showed no changes or even an induction in the case of BT at different sites. Antimicrobial activity toward different commensal strains was reduced, especially in the distal ileum and the cecum in experimental cirrhosis with BT (excluding PVL).

CONCLUSION

Compromised Paneth cell antimicrobial host defense seems to predispose to BT in experimental cirrhosis. Understanding this liver-gut axis including the underlying mechanisms could help us to find new treatment avenues.

Rifaximin improves thrombocytopenia in patients with alcoholic cirrhosis in association with reduction of endotoxaemia

BACKGROUND

Thrombocytopenia is a major haematological disorder of cirrhosis with unclear pathogenesis. Endotoxaemia resulting from intestinal bacterial overgrowth could reduce platelet counts directly or through cytokine release.

AIMS

To correlate endotoxaemia with platelet counts and study the effects of intestinal decontamination with rifaximin on thrombocytopenia in relation to changes in endotoxin and cytokine concentrations in patients with alcoholic cirrhosis.

METHODS

Platelet counts, plasma endotoxin levels and serum interleukin-1 (IL-1), interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) levels were measured in 23 thrombocytopenic cirrhotic patients (platelet count<150 000/μl) before and after 4-week treatment with rifaximin 1200 mg/d (n = 13) or no treatment (n = 10) and at baseline in 10 cirrhotic patients without thrombocytopenia; spleen size was measured at baseline in all patients.

RESULTS

Endotoxin and IL-6 levels were significantly higher in patients with thrombocytopenia than in those without thrombocytopenia (2.76 ± 0.69 vs. 0.64 ± 0.09 EU/ml; P < 0.001 and 24.26 ± 3.38 vs. 2.66 ± 0.74 pg/ml; P = 0.001 respectively). Platelet counts were inversely correlated with endotoxin levels (r = -0.589; P = 0.003), Child-Pugh score (r = -0.625; P = 0.001), IL-6 levels (r = -0.464; P = 0.02) and spleen size (r = -0.455; P = 0.02) in patients with thrombocytopenia. Following rifaximin, platelet counts increased significantly (83 100 ± 9700 vs. 99 600 ± 11 200/μl; P = 0.006) in line with significant reductions in endotoxin (1.28 ± 0.41 vs. 2.54 ± 0.86 EU/ml; P = 0.005), IL-1 (3.1 ± 0.5 vs. 4.4 ± 1.2 pg/ml; P = 0.04), IL-6 (12.8 ± 2.5 vs. 21.1 ± 4.2 pg/ml; P = 0.01) and TNF-α (3.6 ± 1.3 vs. 5.8 ± 1.7; P = 0.02) levels. Platelet count changes were correlated with the changes in endotoxin (r = 0.573; P = 0.04), TNF-α (r = 0.554; P = 0.05) and IL-6 (r = 0.495; P = 0.07) levels.

CONCLUSIONS

Rifaximin improves cirrhosis-related thrombocytopenia and this could be related with the reduction of endotoxaemia.