Spontaneous bacterial peritonitis:the clinical challenge of a leaky gut and a cirrhotic liver

Spontaneous bacterial peritonitis (SBP) is a frequent, life-threatening bacterial infection in patients with liver cirrhosis and ascites. Portal hypertension leads to increased bacterial translocation from the intestine. Failure to eliminate invading pathogens due to immune defects associated with advanced liver disease on the background of genetic predisposition may result in SBP. The efficacy of antibiotic treatment and prophylaxis has declined due to the spread of multi-resistant bacteria. Patients with nosocomial SBP and with prior antibiotic treatment are at a particularly high risk for infection with resistant bacteria. Therefore, it is important to adapt empirical treatment to these risk factors and to the local resistance profile. Rifaximin, an oral, non-absorbable antibiotic, has been proposed to prevent SBP, but may be useful only in a subset of patients. Since novel antibiotic classes are lacking, we have to develop prophylactic strategies which do not induce bacterial resistance. Farnesoid X receptor agonists may be a candidate, but so far, clinical studies are not available. New diagnostic tests which can be carried out quickly at the patient’s site and provide additional prognostic information would be helpful. Furthermore, we need tools to predict antibiotic resistance in order to tailor first-line antibiotic treatment of spontaneous bacterial peritonitis to the individual patient and to reduce mortality

Semiquantitative analysis of intrahepatic CC-chemokine mRNas in chronic hepatitis C.

BACKGROUND: The mechanisms leading to hepatic injury in chronic hepatitis C virus (HCV) infection are only incompletely understood. Recent data propose a correlation of the intrahepatic expression of the CC chemokine RANTES and the degree of periportal and portal inflammatory liver damage. AIM: Here, we have studied the intrahepatic mRNA levels of CC chemokines RANTES together with that of other members of this chemokine family (MIP-1beta, MCP-1, and MCP-2) in chronic hepatitis C as compared with healthy controls. METHODS: Liver samples from 22 HCV-infected patients, nine individuals with primary biliary cirrhosis and from 12 normal controls were included into this study. Intrahepatic mRNA levels of CC chemokines RANTES, MIP-1beta, MCP-1, and MCP-2 were analyzed by a semi-quantitative reverse transcription/real-time polymerase chain reaction assay. RESULTS: In chronic HCV infection, intrahepatic RANTES mRNA levels were significantly higher than in non-infected controls (7.2-fold, p < 0.001) or in the disease control group (2.8-fold, p < 0.001) and higher levels of RANTES mRNA levels were observed in livers with an advanced stage of liver cell injury (histologic activity index > or = 6), although this difference was not statistically significant (p = 0.08). In contrast, mRNA levels of MIP-1beta (p = 0.021) and MCP-1 (p = 0.021) were significantly lower in HCV liver samples while MCP-2 expression was similar in all groups analyzed. CONCLUSION: The data support the concept of chemokines as mediators of liver cell injury in chronic hepatitis C

PNPLA3 gene polymorphism is associated with predisposition to and severity of alcoholic liver disease

The genetic polymorphism with an isoleucine-to-methionine substitution at position 148 (rs738409 C>G) in the patatin-like phospholipase domain protein 3 (PNPLA3) gene confers risk of steatosis. PNPLA3 polymorphism is shown to be associated with alcoholic liver disease (ALD). We performed a systematic review and meta-analysis to examine association of this genetic polymorphism with ALD spectrum and its severity.METHODS:Medline, Embase, and Cochrane Library were searched for studies on association of PNPLA3 polymorphism and ALD spectrum: alcoholic fatty liver (AFL), alcoholic liver injury (ALI), alcoholic cirrhosis (AC), and hepatocellular carcinoma (HCC). Pooled data are reported as odds ratio (OR) with 95% confidence interval. Heterogeneity was assessed using the I 2 statistics and publication bias using Egger's test and Begg and Mazumdar's test. Individual participant data obtained from five studies were used for subgroup analyses.RESULTS:Among 10 studies included in this pooled analysis, compared with controls, OR for rs738409 CG and GG among ALI patients was 1.45 (1.24-1.69) and 2.22 (1.50-3.28), respectively, compared with CC. Respective OR among AC patients was 2.09 (1.79-2.44) and 3.37 (2.49-4.58) and among AC patients with HCC was 2.87 (1.61-5.10) and 12.41 (6.99-22.03). Data for AFL were inconsistent. Among ALD patients, OR of CG and GG genotypes was 2.62 (1.73-3.97) and 8.45 (2.52-28.37), respectively, for AC compared with fatty liver (FL) patients. Similar OR for AC compared with ALI was 1.98 (1.24-3.17) and 3.86 (1.18-12.60). The OR for CG and GG genotypes among AC patients for HCC occurrence was 1.43 (0.76-2.72) and 2.81 (1.57-5.01), respectively. Individual participant data analysis showed age to predispose to AC among ALI patients.CONCLUSIONS:PNPLA3 genetic polymorphism (rs738409 C>G) is associated with increased risk for the entire spectrum of ALD among drinkers including ALI, AC, and HCC. Studies are needed to clarify association of PNPLA3 polymorphism and steatosis in alcoholics. PNPLA3 gene may potentially be a therapeutic target in ALD

TRAIL receptor I (DR4) polymorphisms C626G and A683C are associated with an increased risk for hepatocellular carcinoma (HCC) in HCV-infected patients

<p>Abstract</p> <p>Background</p> <p>Tumour surveillance via induction of TRAIL-mediated apoptosis is a key mechanism, how the immune system prevents malignancy. To determine if gene variants in the TRAIL receptor I (<it>DR4</it>) gene affect the risk of hepatitis C virus (HCV)-induced liver cancer (HCC), we analysed <it>DR4 </it>mutations C626G (rs20575) and A683C (rs20576) in HCV-infected patients with and without HCC.</p> <p>Methods</p> <p>Frequencies of <it>DR4 </it>gene polymorphisms were determined by LightSNiP assays in 159 and 234 HCV-infected patients with HCC and without HCC, respectively. 359 healthy controls served as reference population.</p> <p>Results</p> <p>Distribution of C626G and A683C genotypes were not significantly different between healthy controls and HCV-positive patients without HCC. <it>DR4 </it>variants 626C and 683A occurred at increased frequencies in patients with HCC. The risk of HCC was linked to carriage of the 626C allele and the homozygous 683AA genotype, and the simultaneous presence of the two risk variants was confirmed as independent HCC risk factor by Cox regression analysis (Odds ratio 1.975, 95% CI 1.205-3.236; p = 0.007). Furthermore HCV viral loads were significantly increased in patients who simultaneously carried both genetic risk factors (2.69 ± 0.36 × 10⁶ IU/ml vs. 1.81 ± 0.23 × 10⁶ IU/ml, p = 0.049).</p> <p>Conclusions</p> <p>The increased prevalence of patients with a 626C allele and the homozygous 683AA genotype in HCV-infected patients with HCC suggests that these genetic variants are a risk factor for HCC in chronic hepatitis C.</p

The rs429358 locus in apolipoprotein E is associated with hepatocellular carcinoma in patients with cirrhosis

The host genetic background for hepatocellular carcinoma (HCC) is incompletely understood. We aimed to determine if four germline genetic polymorphisms, rs429358 in apolipoprotein E (APOE), rs2642438 in mitochondrial amidoxime reducing component 1 (MARC1), rs2792751 in glycerol-3-phosphate acyltransferase (GPAM), and rs187429064 in transmembrane 6 superfamily member 2 (TM6SF2), previously associated with progressive alcohol-related and nonalcoholic fatty liver disease, are also associated with HCC. Four HCC case-control data sets were constructed, including two mixed etiology data sets (UK Biobank and FinnGen); one hepatitis C virus (HCV) cohort (STOP-HCV), and one alcohol-related HCC cohort (Dresden HCC). The frequency of each variant was compared between HCC cases and cirrhosis controls (i.e., patients with cirrhosis without HCC). Population controls were also considered. Odds ratios (ORs) associations were calculated using logistic regression, adjusting for age, sex, and principal components of genetic ancestry. Fixed-effect meta-analysis was used to determine the pooled effect size across all data sets. Across four case-control data sets, 2,070 HCC cases, 4,121 cirrhosis controls, and 525,779 population controls were included. The rs429358:C allele (APOE) was significantly less frequent in HCC cases versus cirrhosis controls (OR, 0.71; 95% confidence interval [CI], 0.61-0.84; P=2.9×10−5). Rs187429064:G (TM6SF2) was significantly more common in HCC cases versus cirrhosis controls and exhibited the strongest effect size (OR, 2.03; 95% CI, 1.45-2.86; P=3.1×10−6). In contrast, rs2792751:T (GPAM) was not associated with HCC (OR, 1.01; 95% CI, 0.90-1.13; P=0.89), whereas rs2642438:A (MARC1) narrowly missed statistical significance (OR, 0.91; 95% CI, 0.84-1.00; P=0.043). Conclusion: This study associates carriage of rs429358:C (APOE) with a reduced risk of HCC in patients with cirrhosis. Conversely, carriage of rs187429064:G in TM6SF2 is associated with an increased risk of HCC in patients with cirrhosis

Genetic variants in PNPLA3 and TM6SF2 predispose to the development of hepatocellular carcinoma in individuals with alcohol-related cirrhosis

OBJECTIVES Variants in patatin-like phospholipase domain-containing 3 (PNPLA3; rs738409), transmembrane 6 superfamily member 2 (TM6SF2; rs58542926), and membrane bound O-acyltransferase domain containing 7 (MBOAT7; rs641738) are risk factors for the development of alcohol-related cirrhosis. Within this population, PNPLA3 rs738409 is also an established risk factor for the development of hepatocellular carcinoma (HCC). The aim of this study was to explore possible risk associations of TM6SF2 rs58542926 and MBOAT7 rs641738 with HCC. METHODS Risk variants in PNPLA3, TM6SF2, and MBOAT7 were genotyped in 751 cases with alcohol-related cirrhosis and HCC and in 1165 controls with alcohol-related cirrhosis without HCC. Association with the risk of developing HCC was analyzed using multivariate logistic regression. RESULTS The development of HCC was independently associated with PNPLA3 rs738409 (OR 1.84 [95% CI 1.55-2.18], p = 1.85 × 10) and TM6SF2 rs58542926 (OR 1.66 [1.30-2.13], p = 5.13 × 10), using an additive model, and controlling the sex, age, body mass index, and type 2 diabetes mellitus; the risk associated with carriage of MBOAT7 rs641738 (OR 1.04 [0.88-1.24], p = 0.61) was not significant. The population-attributable fractions were 43.5% for PNPLA3 rs738409, 11.5% for TM6SF2 rs58542926, and 49.9% for the carriage of both the variants combined. CONCLUSIONS Carriage of TM6SF2 rs58542926 is an additional risk factor for the development of HCC in people with alcohol-related cirrhosis. Carriage of both PNPLA3 rs738409 and TM6SF2 rs58542926 accounts for half of the attributable risk for HCC in this population. Genotyping will allow for more precise HCC risk-stratification of patients with alcohol-related cirrhosis, and genotype-guided screening algorithms would optimize patient care

Correction: Genetic Variants in PNPLA3 and TM6SF2 Predispose to the Development of Hepatocellular Carcinoma in Individuals With Alcohol-Related Cirrhosis

Author Pierre Deltenre, MD should appear in the author list in position 25, between Felix Braun and Thomas Berg. He should also have a PhD degree added to his name

Ribavirin exerts differential effects on functions of Cd4+ Th1, Th2, and regulatory T cell clones in hepatitis C.

Ribavirin improves outcomes of therapy in chronic hepatitis C but its mode of action has still remained unclear. Since ribavirin has been proposed to modulate the host's T cell responses, we studied its direct effects on CD4(+) T cell clones with diverse functional polarization which had been generated from patients with chronic hepatitis C. We analysed in vitro proliferation ([(3)H] thymidine uptake) and cytokine responses (IL-10, IFN-gamma) at varying concentrations of ribavirin (0-10 µg/ml) in 8, 9 and 7 CD4(+) TH1, TH2 and regulatory T cell (Treg) clones, respectively. In co-culture experiments, we further determined effects of ribarivin on inhibition of TH1 and TH2 effector cells by Treg clones. All clones had been generated from peripheral blood of patients with chronic hepatitis C in the presence of HCV core protein. Ribavirin enhanced proliferation of T effector cells and increased production of IFN-gamma in TH1 clones, but had only little effect on IL-10 secretion in TH2 clones. However, ribavirin markedly inhibited IL-10 release in Treg clones in a dose dependent fashion. These Treg clones suppressed proliferation of T effector clones by their IL-10 secretion, and in co-culture assays ribavirin reversed Treg-mediated suppression of T effector cells. Our in vitro data suggest that--in addition to its immunostimulatory effects on TH1 cells--ribavirin can inhibit functions of HCV-specific Tregs and thus reverses Treg-mediated suppression of T effector cells in chronic hepatitis C