Patients with cirrhosis and portal hypertension may have alterations in intestinal barrier resulting in increased susceptibility for infections. We investigated the effect of propranolol in gastrointestinal motility, permeability and bacterial overgrowth in cirrhosis.

Patients with cirrhosis and esophageal varices were studied before and after a build-up dose of propranolol according to standard guidelines. Serum TNF-a, IL-6, IL-1b, LPS and bacterial DNA were measured before and during propranolol therapy. Oro-caecal transit time (OCTT) and bacterial overgrowth (BO) have been evaluated with H2 breath testing. Intestinal paracellular (IP), cellular passive non-carrier (ICNC), cellular passive carrier-mediated (ICCM), and gastric permeability (GP) were evaluated by measurement of lactulose, mannitol, D-xylose and sucrose respectively in urine, with high performance liquid chromatography (HPLC).

35 patients with cirrhosis and portal hypertension with median age was 59.6 years (range 42-86) were included in the study. Twenty one had viral hepatitis and 25 were classified as having advanced cirrhosis (Child-Pugh B: 14 or C: 11). Median dose of administrated propranolol was 40 mg/day. After 7 days propranolol treatment BO was resolved in 15 out of 16 patients (93.7%, p = 0.0001) and OCTT was reduced significantly from 180 min to 139 min (SD 58.5, difference - 4 1 min, p = 0.0001). Serum IL-6 levels were reduced in 21/35 (60%) patients from 41.1 to 19 pg/ml (p = 0.01), TNF-a in 10/35 (28.5%) patients from 10.7 to 5.6 pg/ml (p = 0.007) and LPS in 20/35 (57%) from 7.1 to 5.2 mg/L (p = 0.1). No bacterial DNA was detected in serum of all patients either baseline or under propranolol treatment. IP was significantly reduced (0.2 to 0.16, p = 0.04) whereas ICNC (p = 0.9), ICCM (p = 0.4) and GP (p = 0.7) were not affected significantly. Intestinal Permeability (PI) index (Lactulose to Mannitol ratio) was significantly reduced (0.027 to 0.02, p = 0.03).

In patients with cirrhosis and portal hypertension, propranolol use is associated with reduction in BO, increase in intestinal motility and amelioration in intestinal permeability. Moreover IL-6 and LPS levels are being decreased in the majority of patients under propranolol.

Hepatorenal syndrome has conventionally been regarded as a multisystem syndrome in which pathophysiologic pathways that link cirrhosis with impairment in kidney function are followed by dysfunction of several organs such as the heart. The advances in cardiac studies have helped diagnose more subtle cardiac abnormalities that would have otherwise remained unnoticed in a significant subset of patients with advanced liver disease and cirrhosis. Accumulating data suggests that in many instances, the cardiac dysfunction precedes and predicts development of kidney disease in such patients. These observations point to the heart as a key player in hepatorenal syndrome and challenge the notion that the cardiac abnormalities are either the consequence of aberrancies in hepatorenal interactions or have only minor effects. As such, the disturbances traditionally bundled within hepatorenal syndrome may indeed represent a hepatic form of cardiorenal syndrome whereby the liver affects the kidney in part through cardiorenal pathways (that is, hepato-cardio-renal syndrome).

Nucleotide-binding oligomerization domain containing 2 (NOD2) risk variants lead to impaired mucosal barrier function, increased bacterial translocation (BT), and systemic inflammation.

To evaluate the association between the presence of NOD2 risk variants, BT, inflammation, and hepatic encephalopathy (HE).

This prospective multicenter study included patients with cirrhosis and testing for NOD2 risk variants (p.R702W, p.G908R, c.3020insC, N289S, and c.-958T>C). Patients were evaluated for covert (C) and overt (O) HE. Markers of systemic inflammation (leukocytes, CRP, IL-6, LBP) and immune activation (soluble CD14) as well as bacterial endotoxin (hTRL4 activation) were determined in serum.

Overall, 172 patients (70% men; median age 60 [IQR 54-66] years; MELD 12 [IQR 9-16]; 72% ascites) were included, of whom 53 (31%) carried a NOD2 risk variant. In this cohort, 11% presented with OHE and 27% and CHE. Presence and severity of HE and surrogates of inflammation, BT, and immune activation did not differ between patients with and without a NOD2 risk variant, also not after adjustment for MELD. HE was associated with increased ammonia and systemic inflammation, as indicated by elevated CRP (w/o HE: 7.2 [2.7-16.7]; with HE 12.6 [4.5-29.7] mg/dL; p < 0.001) and elevated soluble CD14 (w/o HE 2592 [2275-3033]; with HE 2755 [2410-3456] ng/mL; p = 0.025).

The presence of NOD2 risk variants in patients with cirrhosis is not associated with HE and has no marked impact on inflammation, BT, or immune activation. In contrast, the presence of HE was linked to ammonia, the acute phase response, and myeloid cell activation.

Spontaneous bacterial peritonitis (SBP) is a life-threatening complication of liver cirrhosis with a 1-year mortality of 66%. Bacterial translocation (BT) from the intestine to the mesenteric lymph nodes is crucial for the pathogenesis of SBP.

Since BT presupposes a leaky intestinal epithelium, the integrity of mucus and epithelial cell junctions (E-cadherin and occludin) was examined in colonic biopsies from patients with liver cirrhosis and controls. SBP-inducing Escherichia coli (E. coli) and Proteus mirabilis (P. mirabilis) were isolated from ascites of patients with liver cirrhosis and co-cultured with Caco-2 cells to characterise bacteria-to-cell effects.

SBP-derived E. coli and P. mirabilis led to a marked reduction of cell-to-cell junctions in a dose-dependent and time-dependent manner. This effect was enhanced by a direct interaction of live bacteria with epithelial cells. Degradation of occludin is mediated via increased ubiquitination by the proteasome. Remarkably, a novel bacterial protease activity is of pivotal importance for the cleavage of E-cadherin.

Patients with liver cirrhosis show a reduced thickness of colonic mucus, which allows bacteria-to-epithelial cell contact. Intestinal bacteria induce degradation of occludin by exploiting the proteasome of epithelial cells. We identified a novel bacterial protease activity of patient-derived SBP-inducing bacteria, which is responsible for the cleavage of E-cadherin structures. Inhibition of this protease activity leads to stabilisation of cell junctions. Thus, targeting these mechanisms by blocking the ubiquitin-proteasome system and/or the bacterial protease activity might interfere with BT and constitute a novel innovative therapeutic strategy to prevent SBP in patients with liver cirrhosis.

Spontaneous bacterial peritonitis (SBP) is a severe and often fatal infection in patients with decompensated cirrhosis and ascites. The only cure for SBP is antibiotic therapy, but the emerging problem of bacterial resistance requires novel therapeutic strategies. Human amniotic mesenchymal stromal cells (hA-MSCs) possess immunomodulatory and anti-inflammatory properties that can be harnessed as a therapy in such a context.

An in vitro applications of hA-MSCs in ascitic fluid (AF) of cirrhotic patients, subsequently infected with carbapenem-resistant Enterobacterales, was performed. We evaluated the effects of hA-MSCs on bacterial load, innate immunity factors, and macrophage phenotypic expression.

hA-MSCs added to AF significantly reduce the proliferation of both bacterial strains at 24 h and diversely affect M1 and M2 polarization, C3a complement protein, and ficolin 3 concentrations during the course of infection, in a bacterial strain-dependent fashion.

This study shows the potential usefulness of hA-MSC in treating ascites infected with carbapenem-resistant bacteria and lays the foundation to further investigate antibacterial and anti-inflammatory roles of hA-MSC in in vivo models.

Hemodynamic instability (HDI) during liver transplantation (LT) can be difficult to manage and increases postoperative morbidity and mortality. In addition to surgical causes of HDI, patient- and graft-related factors are also important. Nitric oxide-mediated vasodilatation is a common denominator associated with end-stage liver disease related to HDI. Despite intense investigation, optimal management strategies remain elusive. In this consensus article, experts from the International Liver Transplantation Society, the Liver Intensive Care Group of Europe, and the Society for the Advancement of Transplant Anesthesia performed a rigorous review of the most current literature regarding the epidemiology, causes, and management of HDI during LT. Special attention has been paid to unique LT-associated conditions including the causes and management of vasoplegic syndrome, cardiomyopathies, LT-related arrhythmias, right and left ventricular dysfunction, and the specifics of medical and fluid management in end-stage liver disease as well as problems specifically related to portal circulation. When possible, management recommendations are made.

Norfloxacin administration is useful in preventing bacterial infections in cirrhosis but associated to the generation of resistant species. Rifaximin is known to reach high concentrations in the intestinal lumen without generating relevant resistance in the intestinal flora. Our aim was to compare the effect of Norfloxacin and Rifaximin on intestinal flora composition, bacterial translocation and survival in cirrhotic rats.

Cirrhosis was induced in rats by oral administration of CCl₄ . Animals were divided into three groups: only CCl₄ (group I, n = 10); CCl₄ + Norfloxacin (group II, n = 17) and CCl₄ + Rifaximin (group III, n = 14). Gut bacterial composition, bacterial translocation and cytokine levels were measured.

Forty-one rats were finally included. The incidence of viable and non-viable bacterial translocation was significantly reduced in animals receiving Norfloxacin; Rifaximin also decreased the incidence of viable and non-viable bacterial translocation, but did not reach statistical significance. Serum TNF-α levels were significantly lower in antibiotic groups. Norfloxacin modified intestinal microbiota, depleting significantly more pathobionts than Rifaximin.

Norfloxacin is more effective than Rifaximin in preventing bacterial translocation in rats with cirrhosis probably because of its capacity to reduce pathobionts from intestinal microbiota.

The prognostic impact of the first ever episode of spontaneous bacterial peritonitis (SBP) on patient outcomes is not well described. Our aim was to compare the clinical outcomes of cirrhotic patients with ascites, and with or without a first episode of SBP.

Consecutive patients with cirrhosis and ascites were prospectively enrolled. Demographics, liver and renal function, and hemodynamics were documented at baseline, at resolution of SBP, and thereafter at 4 monthly intervals for 12 months. Complications of cirrhosis and survival were noted.

Twenty-nine cirrhotic patients with a first ever episode of SBP (group A) and 123 control patients slightly younger but similar in gender who never had SBP (group B) were enrolled. At SBP diagnosis, group A had worse liver and renal function (Model of End-Stage Liver Disease : 21.1±10.6 vs. 14.4±5.0), lower serum sodium concentrations, and a more hyperdynamic circulation compared with group B (all P<0.001). SBP resolution resulted in improvement in all measures to baseline levels. During follow-up, group A required more frequent hospital admissions than group B (58% vs. 43%), developed more cirrhotic complications, including further SBP (31% vs. 3%*), hyponatremia (12% vs. 0.8%*), acute kidney injury (50% vs. 23%*), hepatorenal syndrome type 1 (46% vs. 7%*), liver transplantation (62% vs. 30%*), and had a worse overall 1-year survival (38% vs. 70%*) (*P<0.05).

A first SBP episode is commonly followed by multiple complications, and overall worse prognosis. Consideration should be given to assess cirrhotic patients for liver transplant after the first episode of SBP.

Endoscopic variceal ligation (EVL) and endoscopic variceal sclerotherapy (EVS) are the main therapeutic procedures for the emergency treatment and secondary prophylaxis of esophageal varices in cirrhotics. Post-endoscopic bacteremia has been reported after EVS and EVL, but data on the frequency of bacteremia are conflicting. This study aims to provide incidences of bacteremia after EVS and EVL in different settings through meta-analysis.

Only prospective or randomized studies were included in this meta-analysis. Binomial distribution was used to compute variance for each study. Random effects models were used as the final model for estimating the effect size and 95 % confidence interval. Adjusted effects were obtained using meta-regression analysis.

Nineteen prospective studies involving 1001 procedures in 587 patients were included in the meta-analysis on the risk of bacteremia after EVS or EVL in cirrhotics with esophageal varices. The frequency of bacteremia after endoscopic variceal therapy was 13 %. The frequency of bacteremia after EVS (17 %) was higher than after EVL (6 %) with no statistically significant difference (P = 0.106). The frequency of bacteremia after elective EVS (14 %) was significantly less than after emergency EVS (22 %) (P < 0.001). The frequency of bacteremia after elective EVL (7.6 %) was not significantly different from after emergency EVL (3.2 %) (P = 0.850).

The incidence of bacteremia is low in patients with cirrhosis and varices after esophageal variceal therapy. These results are consistent with our current guidelines that antibiotic prophylaxis before endoscopic variceal therapy is only necessary for bleeding patients.

In patients with decompensated cirrhosis, bacterial translocation can contribute to splanchnic vasodilatation, decreased effective circulating volume, and portal hypertension. The primary objective of this randomized, double blind placebo controlled trial was to evaluate the effect of the probiotic VSL#3(®) on the hepatic venous pressure gradient (HVPG).

Seventeen patients with decompensated cirrhosis and an HVPG of ≥ 10 mmHg were randomized to receive 2 months of VSL#3(®) or an identical placebo. HVPG, endotoxin, interleukin (IL)-6, IL-8, IL-10, renin, aldosterone, nitric oxide and stool microbiota were measured at baseline and study end.

Two of the 17 patients were taken off the trial before completion (one for alcohol abuse and the second for SBP - both in placebo arm). Data were analysed on the remaining 15 patients. The median model for end-stage liver disease score was 12, and 80% of patients had Child Pugh B disease. The treatment arm had a greater decrease in HVPG from baseline to study end than the placebo arm (median change from baseline -11.6% vs +2.8%), although this reduction was not statistically significant in either group. There was a significant reduction in the plasma aldosterone level in the VSL#3(®) group, but no significant changes in the other measured parameters, including the stool microflora analysis.

Within the limitations of our sample size, VSL#3(®) therapy does not appear to have a significant impact on portal pressure reduction in patients with decompensated cirrhosis.

Proton pump inhibitors (PPIs) facilitate intestinal bacterial translocation. No robust data exist demonstrating that PPIs increase the risk of spontaneous bacterial peritonitis (SBP) and that PPIs worsen the prognosis of SBP patients. PPI use might be unsuitable for cirrhotic patients.

To analyse: (i) the role of PPIs in the occurrence of SBP in cirrhotic patients; (ii) their impact on the prognosis of SBP patients; and (iii) the suitability of their use.

In this retrospective case-control study, PPI use was first assessed in cirrhotic patients consecutively admitted with SBP (group I) and in a control group that included the same number of uninfected cirrhotic patients with ascites (group II). Afterwards, the impact of PPIs on SBP was assessed in group I by comparing survival of patients with and without PPIs.

A total of 102 patients were included, 51 in each group. (i) SBP patients were more frequently treated by PPIs than controls (49 vs. 25%, P = 0.014). (ii) In group I, patients with (n = 25) and without (n = 26) PPIs had similar survival rates at 1 month (64.0 ± 9.6% vs. 59.4 ± 10.0%), 3 months (41.2 ± 10.2% vs. 44.6 ± 10.6%), and 1 year (26.6 ± 9.6% vs. 28.9 ± 10.1%), and similar median age at death (53 vs. 57 years). (iii) The reason for PPI use was inappropriate or undocumented in 34% of group I and II.

Proton pump inhibitors were more frequently used in SBP patients than in controls, but did not influence the prognosis in SBP. Overuse of PPIs was encountered in one-third of cirrhotic patients and should be avoided.

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

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.

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.

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.

  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.

  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.

  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.

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

There is increasing evidence that proton pump inhibitors (PPIs) increase the rate of infections in patients with decompensated cirrhosis.

To estimate the extent to which proton pump inhibitors (PPIs) increase the rate of infections among patients with decompensated cirrhosis.

We conducted a retrospective propensity-matched new user design using US Veterans Health Administration data. Only decompensated cirrhotic patients from 2001 to 2009 were included. New PPI users after decompensation (n = 1268) were 1:1 matched to those who did not initiate gastric acid suppression. Serious infections, defined as infections associated with a hospitalisation, were the outcomes. These were separated into acid suppression-related (SBP, bacteremia, Clostridium difficile and pneumonia) and non-acid suppression-related. Time-varying Cox models were used to estimate adjusted hazard ratios (HR) and 95% CIs of serious infections. Parallel analyses were conducted with H2 receptor antagonists (H2RA).

More than half of persons with decompensated cirrhosis were new users of gastric acid suppressants, with most using PPIs (45.6%) compared with H2RAs (5.9%). In the PPI propensity-matched analysis, 25.3% developed serious infections and 25.9% developed serious infections in the H2RA analysis. PPI users developed serious infections faster than nongastric acid suppression users (adjusted HR: 1.66; 95% CI: 1.31–2.12). For acid suppression-related serious infections, PPI users developed the outcome at a rate 1.75 times faster than non-users (95% CI: 1.32–2.34). The H2RA findings were not statistically significant (HR serious infections: 1.59; 95% CI: 0.80–3.18; HR acid suppression-related infections: 0.92; 95% CI: 0.31–2.73).

Among patients with decompensated cirrhosis, proton pump inhibitors but not H2 receptor antagonists increase the rate of serious infections.

Bacterial translocation is a frequent event in cirrhosis leading to an increased inflammatory response. Splanchnic adrenergic system hyperactivation has been related with increased bacterial translocation. We aim at evaluating the interacting mechanism between hepatic norepinephrine and inflammation during liver damage in the presence of bacterial-DNA.

Forty-six mice were included in a 16-week protocol of CCl(4)-induced cirrhosis. Laparotomies were performed at weeks 6, 10, 13 and 16. A second set of forty mice injected with a single intraperitoneal dose of CCl(4) was treated with saline, 6-hydroxidopamine, Nebivolol or Butoxamine. After 5 days, mice received E. coli-DNA intraperitoneally. Laparotomies were performed 24 hours later. Liver bacterial-DNA, norepinephrine, TNF-alpha, IL-6 and beta-adrenergic receptor levels were measured.

Bacterial-DNA translocation was more frequent in CCl(4)-treated animals compared with controls, and increased as fibrosis progressed. Liver norepinephrine and pro-inflammatory cytokines were significantly higher in mice with vs without bacterial-DNA (319.7 ± 120.6 vs 120.7 ± 68.6 pg/g for norepinephrine, 38.4 ± 6.1 vs 29.7 ± 4.2 pg/g for TNF-alpha, 41.8 ± 7.4 vs 28.7 ± 4.3 pg/g for IL-6). Only beta-adrenergic receptor-1 was significantly increased in treated vs control animals (34.6 ± 7.3 vs 12.5 ± 5.3, p=0.01) and correlated with TNF-alpha, IL-6 and norepinephrine hepatic levels in animals with bacterial-DNA. In the second set of mice, cytokine levels were increased in 6-hydroxidopamine and Nebivolol (beta-adrenergic receptor-1 antagonist) treated mice compared with saline. Butoxamine (beta-adrenergic receptor-2 antagonist) didn't inhibit liver norepinephrine modulation of pro-inflammatory cytokines.

Beta-adrenergic receptor-1 mediates liver norepinephrine modulation of the pro-inflammatory response in CCl(4)-treated mice with bacterial-DNA.

Gut is the major source of endogenous bacteria causing infections in advanced cirrhosis. Intestinal barrier dysfunction has been described in cirrhosis and account for an increased bacterial translocation rate.

We hypothesize that microbiota composition may be affected and change along with the induction of experimental cirrhosis, affecting the inflammatory response.

Progressive liver damage was induced in Balb/c mice by weight-controlled oral administration of carbon tetrachloride. Laparotomies were performed at weeks 6, 10, 13 and 16 in a subgroup of treated mice (n = 6/week) and control animals (n = 4/week). Liver tissue specimens, mesenteric lymph nodes, intestinal content and blood were collected at laparotomies. Fibrosis grade, pro-fibrogenic genes expression, gut bacterial composition, bacterial translocation, host's specific butyrate-receptor GPR-43 and serum cytokine levels were measured.

Expression of pro-fibrogenic markers was significantly increased compared with control animals and correlated with the accumulated dose of carbon tetrachloride. Bacterial translocation episodes were less frequent in control mice than in treated animals. Gram-positive anaerobic Clostridia spp count was decreased in treated mice compared with control animals and with other gut common bacterial species, altering the aerobic/anaerobic ratio. This fact was associated with a decreased gene expression of GPR43 in neutrophils of treated mice and inversely correlated with TNF-alpha and IL-6 up-regulation in serum of treated mice along the study protocol. This pro-inflammatory scenario favoured blood bacterial translocation in treated animals, showing the highest bacterial translocation rate and aerobic/anaerobic ratio at the same weeks.

Gut microbiota alterations are associated with the development of an inflammatory environment, fibrosis progression and bacterial translocation in carbon tetrachloride-treated mice.

The straight relationship between cirrhosis and impaired intestinal barrier has not been elucidated yet.

To verify (51)Cr-EDTA-intestinal permeability in rats with CCl(4)-induced cirrhosis and controls.

Fifty male Wistar rats weighing 150-180 g were separated in three groups: 25 animals received CCl(4) 0.25 mL/kg with olive oil by gavage with 12 g/rat/day food restriction for 10 weeks (CCl(4)-induced cirrhosis); 12 received the same food restriction for 10 weeks (CCl(4)-non exposed). Other 13 rats received indomethacin 15 mg/kg by gavage as positive control of intestinal inflammation.

The median (25-75 interquartile range) (51)Cr-EDTA-IP values of cirrhotic and CCl(4)-non exposed rats were 0.90% (0.63-1.79) and 0.90% (0.60-1.52) respectively, without significant difference (P = 0.65). Animals from indomethacin group showed (51)Cr-EDTA-IP, median 7.3% (5.1-14.7), significantly higher than cirrhotic and CCl(4)-non exposed rats (P<0.001).

This study showed the lack of difference between (51)Cr-EDTA-intestinal permeability in rats with and without cirrhosis. Further studies are necessary to better clarify the relationship between intestinal permeability and cirrhosis.

Liver cirrhosis is associated with a wide range of cardiovascular abnormalities including hyperdynamic circulation, cirrhotic cardiomyopathy, and pulmonary vascular abnormalities. The pathogenic mechanisms of these cardiovascular changes are multifactorial and include neurohumoral and vascular dysregulations. Accumulating evidence suggests that cirrhosis-related cardiovascular abnormalities play a major role in the pathogenesis of multiple life-threatening complications including hepatorenal syndrome, ascites, spontaneous bacterial peritonitis, gastroesophageal varices, and hepatopulmonary syndrome. Treatment targeting the circulatory dysfunction in these patients may improve the short-term prognosis while awaiting liver transplantation. Careful fluid management in the immediate post-transplant period is extremely important to avoid cardiac-related complications. Liver transplantation results in correction of portal hypertension and reversal of all the pathophysiological mechanisms that lead to the cardiovascular abnormalities, resulting in restoration of a normal circulation. The following is a review of the pathogenesis and clinical implications of the cardiovascular changes in cirrhosis.

Bacterial infections and severity of associated inflammatory reaction influence prognosis in patients with advanced cirrhosis. We compared the innate immune response to bacterial DNA (bactDNA) translocation with that caused by viable bacteria translocation in patients with spontaneous bacterial peritonitis and the relationship between the cytokine response and serum levels of bactDNA. The bactDNA translocation was investigated in 226 patients with cirrhosis and noninfected ascites, 22 patients with spontaneous bacterial peritonitis, and 10 patients with ascites receiving continuous norfloxacin. Serum and ascitic fluid tumor necrosis factor alpha, interferon-gamma, interleukin-12, and nitric oxide metabolites were measured via enzyme-linked immunosorbent assay. Bacterial genomic identifications were made via amplification and sequencing of the 16S ribosomal RNA gene and digital quantization with DNA Lab-on-chips. The bactDNA was present in 77 noninfected patients (34%) and in all cases of spontaneous bacterial peritonitis, even in those with culture-negative ascitic fluid. No patient receiving norfloxacin showed bactDNA translocation. Levels of all cytokines were similar in patients with bactDNA translocation or spontaneous bacterial peritonitis and significantly higher than in patients without bactDNA or in those receiving norfloxacin. Serum bactDNA concentration paralleled levels of all cytokines and nitric oxide in a series of patients with bactDNA translocation or spontaneous bacterial peritonitis followed during 72 hours. Antibiotic treatment in the series of patients with spontaneous bacterial peritonitis did not abrogate bactDNA translocation in the short term.

bactDNA translocation-associated cytokine response is indistinguishable from that in patients with spontaneous bacterial peritonitis and is dependent on bactDNA concentration. Norfloxacin abrogates bactDNA translocation and cytokine response.

To evaluate 16S ribosomal RNA (rRNA) gene amplification to diagnose spontaneous bacterial peritonitis (SBP).

According to a retrospective protocol, 31 patients with portal hypertensive ascites (serum to ascites albumin gradient > or = 1.1 g/dL) were studied. Ascitic fluid was analyzed as follows: Gram stain, aerobic and anaerobic cultures, polymorphonuclear cell count, and biochemical tests. Bacterial DNA was detected by polymerase chain reaction.

There were 8 episodes of SBP and 4 episodes of bacterascites (BA). Culture was positive in 4 of 8 cases of SBP and bacterial DNA was positive in 7 of 8 cases of SBP. Bacterial DNA was positive in 3 of 4 cases of BA and in 8 of 28 cases of culture-negative non-neutrocytic ascites (CNNNA). The PELD score, serum to albumin ascites gradient, and mortality showed no statistical difference between patients with CNNNA and the result of the bacterial DNA analysis.

Although the 16S rRNA gene amplification was better than culture to diagnose SBP, bacterial DNA does not seem to allow a distinction between ascites infection and ascites colonization.

Translocation of intestinal bacteria to ascitic fluid is, probably, the first step in the development of spontaneous bacterial peritonitis in patients with cirrhosis. Proteins of the complement system are soluble mediators implicated in the host immune response to bacterial infections and its activation has been traditionally considered to be an endotoxin-induced phenomenon. The aim of this study was to compare the modulation of these proteins in response to the presence of bacterial DNA and/or endotoxin in patients with advanced cirrhosis and ascites in different clinical conditions. Groups I and II consisted of patients without/with bacterial DNA. Group III included patients with spontaneous bacterial peritonitis and Group IV with patients receiving norfloxacin as secondary long-term prophylaxis of spontaneous bacterial peritonitis. Serum and ascitic fluid levels of endotoxin and truncated residues of the complement system were measured by ELISA. The complement system is triggered in response to bacterial DNA, as evidenced by significantly increased levels of C3b, membrane attack complex, and C5a in patients from Groups II and III compared with patients without bacterial DNA (Group I) and those receiving norfloxacin (Group IV). Gram classification did not further differentiate the immune response between patients within groups II and III, even though endotoxin levels were, as expected, significantly higher in patients with bacterial DNA from gram-negative microorganisms. The complement protein activation observed in patients with bacterial DNA in blood and ascitic fluid is indistinguishable from that observed in patients with spontaneous bacterial peritonitis and may occur in an endotoxin-independent manner.

Bacterial translocation (BT) is a phenomenon in which live bacteria or its products cross the intestinal barrier. Gut translocation of bacteria has been shown in both animal and human studies. BT and its complications have been shown clearly to occur in animal models, but its existence and importance in humans has been difficult to ascertain. We review the mechanisms of BT and its clinical impact based on the current literature.

Patients with cirrhosis are at increased risk of developing infections due to bacterial translocation. This process depends on three principal factors: bacterial overgrowth, immunodepression, and altered intestinal permeability. Intestinal barrier functions may be disturbed in cirrhosis, related to the toxic effects of alcohol (on mucosa and biological membranes) and portal hypertensive enteropathy. Few studies on the assessment of intestinal permeability in cirrhotic patients are available, and contradictory results may be explained by methodological differences. However, four studies using a differential sugar absorption test (lactulose-mannitol test, a combination of an oligosaccharide and a monosaccharide) showed an increased intestinal permeability in cirrhotic patients. The recurrence of spontaneous bacterial peritonitis can be appreciated only by one similar case history, a low rate of protides in ascites (<10 g/L), bilirubinemia > 55 micromol/L, and thrombocytopenia<98.000/mm3. These results suggest that primary antibiotherapy prophylaxis should be recommended, but this recommendation is limited by the risk of bacterial resistant selection and by the fact that no patient survival benefits was shown. Intestinal permeability could be another predictive factor to justify preventive antibiotherapy; but more studies are needed and methods should be standardized (technique used to measure permeability, patient groups involved).

Abnormal vascular tone is responsible for many of the complications seen in cirrhosis making the identification of the pathophysiology of abnormal dilatation a major focus in hepatology research. The study of abnormal vascular tone is complicated by the multiple vascular beds involved (hepatic, splanchnic, peripheral, renal and pulmonary), the differences in the underlying cause of portal hypertension (hepatic versus pre-hepatic) and the slow evolution of the hyperdynamic state. The autonomic nervous system, circulating vasodilators and abnormalities in vascular smooth muscle cells (receptors, ion channels, signalling systems and contraction) have all been implicated. There is overwhelming evidence for an overproduction of NO (nitric oxide) contributing to the peripheral dilatation in both animal models of, and in humans with, cirrhosis and portal hypertension. This review focuses on the proposal that endotoxaemia, possibly from gut-derived bacterial translocation, causes induction of NOS (NO synthase) leading to increased vascular NO production, which is the primary stimulus for the development of vasodilatation in cirrhosis and its accompanying clinical manifestations. The current controversy lies not in whether NO production is elevated, but in which isoform of NOS is responsible. We review the evidence for endotoxaemia in cirrhosis and the factors contributing to gut-derived bacterial translocation, including intestinal motility and permeability, and finally discuss the possible role of selective intestinal decontamination in the management of circulatory abnormalities in cirrhosis.

The gut flora plays an important role in the pathogenesis of the complications of cirrhosis. Cirrhotic patients are prone to develop bacterial infections, mainly the 'spontaneous' infection of ascites or spontaneous bacterial peritonitis. Other complications of cirrhosis, such as variceal haemorrhage and ascites, occur mostly or solely as a consequence of portal hypertension. Portal pressure increases initially as a consequence of an increased intrahepatic resistance but, once collaterals have formed, high portal pressure is maintained by an increased splanchnic blood inflow secondary to vasodilatation. Splanchnic vasodilatation is the initiating event in the hyperdynamic circulatory state that aggravates the complications of cirrhosis. The gut flora plays a role in both the development of infections and in the hyperdynamic circulatory state of cirrhosis and, although less prominently, it also plays a role in the pathogenesis of hepatic encephalopathy. This chapter presents evidence regarding gut flora and its modification in the pathogenesis and management of these complications of cirrhosis.

Various Helicobacter species have been isolated from the stomach, intestinal tract and liver of a variety of mammalian and some avian species, and Helicobacter DNA has been detected in human bile and liver samples. An immunoblot assay was established to analyse serum antibody responses to non-gastric Helicobacter species in patients with autoimmune liver diseases, in comparison with healthy individuals. Sera from 36 patients with primary sclerosing cholangitis (PSC), 21 with primary biliary cirrhosis, 19 with autoimmune chronic hepatitis and 80 blood donors were analysed by immunoblot, using cell-surface proteins from Helicobacter pullorum, Helicobacter bilis and Helicobacter hepaticus as antigens. Prior to testing, sera were cross-absorbed with a whole-cell lysate of Helicobacter pylori. Antibody reactivity to various proteins of these three Helicobacter species was measured by densitometric scanning and results were processed by computer software to estimate antigenic specificity. Results were also compared with antibody response to H. pylori. For H. pullorum, reactivity to at least two of the proteins with molecular masses of 48, 45, 37, 20 and 16 kDa, for H. hepaticus, reactivity to the 76, 30 and 21 kDa proteins and for H. bilis, reactivity to the 22 and 20 kDa proteins, seemed to have high specificity. Positive immunoblot results with sera from patients with PSC to antigens of H. pullorum, H. bilis and H. hepaticus were found in 38, 22 and 25 % of cases, respectively, and from patients with other autoimmune liver diseases, in 30, 22 and 22 % of cases, respectively. Prevalence of serum antibodies to non-gastric Helicobacter species was significantly higher in patients with autoimmune chronic liver diseases than in healthy blood donors (P < 0.001). Increased antibody levels to enterohepatic Helicobacter species raise questions concerning an infectious role of these emerging bacterial pathogens in human autoimmune liver diseases.

Carbon monoxide, a product of the heme-oxygenase (HO) pathway, is an important endogenous vasoactive substance. Production of CO has not been assessed in human cirrhosis. The aim of this study was to assess production of CO in patients with cirrhosis with and without spontaneous bacterial peritonitis (SBP). CO concentration in the exhaled air and blood carboxyhemoglobin (COHb) levels, as estimates of total HO activity, were determined in 16 healthy subjects, 32 noninfected cirrhotic patients (20 with ascites), and 19 patients with SBP, all nonsmokers. Noninfected cirrhotic patients had a CO concentration in the exhaled air and COHb levels significantly higher compared with values of healthy subjects (2.3 +/- 0.2 ppm vs. 0.7 +/- 0.1 ppm and 1.0% +/- 0.1% vs. 0.6% +/- 0.1%, respectively; P <.05 for both). Patients with ascites had the highest values. Both CO concentration in the exhaled air and COHb levels were very high in patients with SBP (5.6 +/- 0.6 ppm and 1.9% +/- 0.2%; P <.01 vs. the other 2 groups) and decreased slowly after resolution of the infection, reaching values similar to those of noninfected patients 1 month after SBP. In patients with SBP, there was a significantly direct correlation between CO and plasma renin activity (PRA) (r = 0.71, P <.001). In conclusion, these results support the existence of increased CO production in human cirrhosis, which further increases in the setting of SBP. Increased CO production may participate in the disturbance of circulatory function that occurs during severe bacterial infections in cirrhosis.

Probiotics and antioxidants could be alternatives to antibiotics in the prevention of bacterial infections in cirrhosis. The aim of the present study was to determine the effect of Lactobacillus johnsonii La1 and antioxidants on intestinal flora, endotoxemia, and bacterial translocation in cirrhotic rats.

Twenty-nine Sprague-Dawley rats with cirrhosis induced by CCl(4) and ascites received Lactobacillus johnsonii La1 10(9)cfu/day in vehicle (antioxidants: vitamin C+glutamate) (n=10), vehicle alone (n=11), or water (n=8) by gavage. Another eight non-cirrhotic rats formed the control group. After 10 days of treatment, a laparotomy was performed to determine microbiological study of ileal and cecal feces, bacterial translocation, endotoxemia, and intestinal malondialdehyde (MDA) levels as index of intestinal oxidative damage.

Intestinal enterobacteria and enterococci, bacterial translocation (0/11 and 0/10 vs. 5/8, P<0.01), and ileal MDA levels (P<0.01) were lower in cirrhotic rats treated with antioxidants alone or in combination with Lactobacillus johnsonii La1 compared to cirrhotic rats receiving water. Only rats treated with antioxidants and Lactobacillus johnsonii La1 showed a decrease in endotoxemia with respect to cirrhotic rats receiving water (P<0.05).

Antioxidants alone or in combination with Lactobacillus johnsonii La1 can be useful in preventing bacterial translocation in cirrhosis.

Spontaneous bacterial peritonitis (SBP) is the most common and serious infection that develops in cirrhotic patients. Translocation of bacteria from their intestinal origin, alterations in immune defence mechanisms and deficiencies in the ascitic fluid antimicrobial activity seem to represent the main steps in the pathogenesis of SBP in cirrhosis. Among the factors determining the development of bacterial translocation, intestinal bacterial overgrowth (mainly related to decreased intestinal motility) and changes in the intestinal barrier appear to play an outstanding role. In conclusion, greater understanding of the pathogenesis of SBP will allow better identification of patients at high risk of developing this complication and contribute to the search for new strategies for its prevention.