The transhepatic endotoxin gradient is present despite liver cirrhosis and is attenuated after transjugular portosystemic shunt (TIPS).
- Daniel Benten†1,
- Julian Schulze zur Wiesch†1Email author,
- Karsten Sydow2,
- Andreas Koops3,
- Peter Buggisch1,
- Rainer H Böger4,
- Charlotte A Gaydos5,
- Helen Won5,
- Veronica Franco5,
- Ansgar W Lohse1,
- Stuart C Ray5 and
- Ashwin Balagopal5
© Benten et al; licensee BioMed Central Ltd. 2011
Received: 19 June 2011
Accepted: 6 October 2011
Published: 6 October 2011
Translocation of gut-derived bacterial products such as endotoxin is a major problem in liver cirrhosis.
To assess the hepatic clearance of bacterial products in individuals with cirrhosis, we tested concentrations of Gram-negative bacterial lipopolysaccharide (LPS), LPS-binding protein (LBP), and the precursor of nitric oxide (NO), L-arginine, in a cohort of 8 stable patients with liver cirrhosis before and after elective transjugular portosystemic shunt (TIPS) implantation, including central venous, hepatic venous, and portal venous measurements.
Using an adapted LPS assay, we detected high portal venous LPS concentrations (mean 1743 ± 819 pg/mL). High concentrations of LPS were detectable in the central venous blood (931 ± 551 pg/mL), as expected in persons with cirrhosis. The transhepatic LPS gradient was found to be 438 ± 287 pg/mL, and 25 ± 12% of portal LPS was cleared by the cirrhotic liver. After TIPS, central venous LPS concentrations increased in the hepatic and central veins, indicating shunting of LPS with the portal blood through the stent. This paralleled a systemic increase of L-arginine, whereas the NO synthase inhibitor asymmetric dimethylarginine (ADMA) remained unchanged, suggesting that bacterial translocation may contribute to the pathogenesis of circulatory dysfunction post-TIPS.
This study provides quantitative estimates of the role of the liver in the pathophysiology of bacterial translocation. The data indicate that the cirrhotic liver retains the capacity for clearance of bacterial endotoxin from the portal venous blood and that TIPS implantation attenuates this clearance. Thus, increased endotoxin concentrations in the systemic circulation provide a possible link to the increased encephalopathy in TIPS patients.
Systemic translocation of gut-derived bacteria and their products is a risk factor for recurrent spontaneous bacterial peritonitis and/or encephalopathy in patients with liver cirrhosis [1, 2]. For decades, there has been great interest in unraveling the pathophysiology of bacterial translocation in cirrhosis . Experimental data derived from animal studies demonstrated portal and systemic bacteremia, predominantly Gram-negative organisms, in cirrhotic animals with portal hypertension [4–6]. Research conducted 20-30 years ago suggested an important role for endotoxemia in liver cirrhosis, but the assays available at that time were less sensitive and human portal blood sampling is challenging [6, 7]. Recent detection of bacterial translocation during HIV infection, thought to result from increased gut permeability, provided a plausible cause of systemic immune activation; however, parallel studies in, HBV, HCV and HIV-HCV co-infection demonstrated that bacterial translocation is strongly associated with cirrhosis, raising questions of cause and effect [8–11]. In this context, we and others have improved the sensitivity of standard LPS assays .
The implantation of a transjugular intrahepatic portosystemic shunt (TIPS) has become a standard procedure for the treatment of complications of portal hypertension [13, 14]. Although of proven benefit in decompensated liver cirrhosis, TIPS is associated with significant mortality and morbidity from worsened hepatic encephalopathy and hematogenous infections . It is thought that these complications of TIPS are, in part, due to the diminished hepatic clearance of bacterial products , although the change in clearance has not been measured. The implantation of TIPS offers an opportunity to directly quantify LPS in various compartments of the human circulation including the portal vein [17, 18].
Here, we assess concentrations of LPS and the precursor of nitric oxide (NO), L-arginine, in a cohort of patients with liver cirrhosis undergoing TIPS implantation to determine the transhepatic LPS gradient in vivo before and after TIPS [17–19].
Plasma samples were collected from 8 consecutive patients with liver cirrhosis and either refractory ascites, or recurrent bleeding from varices, undergoing TIPS placement between 2006 and 2007. Spontaneous bacterial peritonitis was excluded in all patients using ascitic fluid criteria (< 250 polymorphonuclear cells per μL), and no patient had systemic infection or active variceal bleeding. Informed consent was obtained from each patient included in the study and the study protocol conforms to the ethical guidelines of the 1975 Declaration of Helsinki as reflected in a priori approval by the institution's human research committee.
Blood was obtained during a standard TIPS procedure. After cannulation of the internal jugular vein and insertion of a LEV2 catheter (Cook Medical, Germany), blood was obtained before TIPS from the right atrium (central venous) and from the hepatic vein close to the junction with the inferior vena cava. After puncture of the portal vein, blood was drawn from its trunk. Approximately 15 min after TIPS placement, blood was again obtained from the hepatic vein at the junction to the inferior vena cava. The final blood sample after TIPS placement was again drawn from the right atrium. All blood samples were immediately cooled on ice, centrifuged for 10 min under 2,000 g and plasma was stored at -80°C. All patients were fasting for at least 8 hours before the procedure.
LPS concentrations were measured in plasma diluted to 1:250 and 1:500 using a Limulus Amebocyte Lysate assay (LONZA, Walkersville, MD) as previously described , with modifications . For LPS-binding protein (LBP) measurement, plasma was diluted 1:800 and measured using a commercially available plate-based ELISA assay according to the manufacturer's specifications (Cell Sciences, Canton, MA).
For quantification of 16s rDNA, DNA was extracted from a 200 μL aliquot of plasma samples after lysis and purification using the Roche MagNA Pure system (Roche Diagnostics, Indianapolis, IN). 16s rDNA was PCR amplified using a set of universal primers and probe (forward primer [P891F] 5'TGGAGCATGTGGTTTAATTCGA; reverse primer [P1033R] TGCGGGACTTAACCCAACA; UniProbe CACGAGCTGACGACARCCATGCA) that have been validated as sensitive and specific for bacterial detection to the limit of 5 pg of contaminating DNA [20, 21].
L-arginine, asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) plasma concentrations were determined by liquid chromatography tandem mass spectrometry as recently described .
The paired t-test was used for inter-group comparisons. All data are expressed as mean ± SD. P values of 0.05 or less were considered significant.
Cause of liver cirrhosis
Indication for TIPS
Central venous LPS before TIPS (μmol/l)
Ascites, hepatorenal syndrome
Ascites, variceal bleeding
Ascites, partial portal vein thrombosis
Varices, partial portal vein thrombosis
Recurrent variceal bleeding, hydrothorax
To facilitate comparison of individual clearance rates pre-/post-TIPS insertion in the various compartments, LPS concentrations were individually normalized to levels in the portal vein (set as 100% in each patient, Figure 1C). On average, the pre-TIPS LPS concentration in the hepatic vein was 75 ± 12%, which corresponds to a hepatic LPS clearance of 25 ± 12%. After TIPS, the hepatic vein LPS concentration increased to 92 ± 16% of the portal vein concentrations, a trend indicating shunting of LPS with the portal venous blood through the stent and loss of the THEG. The central venous LPS concentration increased from 52 ± 10% to 68 ± 15% of the portal venous concentration (Figure 1C).
LBP is intimately connected with the host response to LPS, but freely circulates in all blood compartments and is not expected to be cleared by the liver; therefore, as a negative control we measured LBP concentrations in the right atrium, hepatic, and portal vein and found no transhepatic gradient before or after TIPS (Figure 1C). Bacterial DNA was measured using a quantitative PCR assay for 16s rDNA. Bacterial DNA was found in 37/40 tested samples, but there was no relationship or gradient between 16s rDNA concentrations pre- and post-TIPS in the various blood compartments (data not shown).
It has recently been shown that the presence of bacterial DNA, a marker of bacterial translocation, was associated with aggravation of NO-mediated peripheral vasodilation in patients with liver cirrhosis . In addition NO production resulted from endotoxemia . Thus, we measured L-arginine as an NO precursor in the various compartments before and after TIPS. In the portal vein, L-arginine plasma concentrations were higher than in the hepatic vein before TIPS (77.4 ± 10.0 vs. 51.2 ± 8.1 μmol/l, p < 0.01). After TIPS, concentrations in the hepatic vein increased to 77.0 ± 11.8 μmol/l, similar to the portal vein levels. Also, the central venous L-arginine concentration increased from 66.9 ± 12.4 μmol/l pre-TIPS to 78.4 ± 13.2 μmol/l after TIPS (p < 0.05). Interestingly, concentrations of the endogenous NO synthase inhibitor ADMA and SDMA were similar in all compartments before and after TIPS (p = n.s., data not shown).
In healthy individuals, only minimal amounts of endotoxin are found in peripheral venous blood, since hepatic macrophages (Kupffer cells) are believed to clear the endotoxin from intestinal bacteria that enter the portal vein [3, 24–26]. In contrast, endotoxin is frequently detected in the peripheral blood of cirrhotic patients resulting from both increased translocation from the gut and reduced hepatic clearance [27–29]. However, clinical studies on the pathophysiology of bacterial translocation and hepatic endotoxin clearance in cirrhosis have been challenging due to the problem of accessing the portal vein in humans, emphasizing the demand for new diagnostic strategies. Recently, a trial in cirrhotic patients has shown that presence of bacterial DNA, a marker of bacterial translocation, was associated with aggravation of peripheral vasodilation and worsening of intrahepatic endothelial dysfunction . To further assess the impact of bacterial translocation in patients with decompensated cirrhosis, we screened a series of patients undergoing elective TIPS implantation for changes in endotoxemia before and after shunting blood from the liver.
A striking difference from previous studies is the high concentration of systemic endotoxemia detected in our cohort of patients. The Limulus Amebocyte Lysate (LAL) assay for LPS quantification has been extensively reported to be inhibited by mammalian plasma and serum. We have recently reported that in a cohort of HIV-infected persons and SIV-infected macaques, plasma dilutions of ≥ 1:200 were required to diminish the assay inhibition of plasma, revealing concentrations comparable with those reported here .
Recently, a well-designed trial in patients undergoing emergency TIPS for uncontrollable variceal bleeding has examined hemodynamic changes in systemic and cerebral blood flow and found systemic endotoxemia to be associated with increased NO production . The assessment of systemic LPS concentrations in such severely ill patients, however, may not be representative of our cohort, which consists of stable patients receiving elective TIPS given the strong possibility of transient endotoxinemia due to instrumentation and bleeding in the former group [30, 31]. Paradoxically, only one-half of individuals in that study had detectable LPS and even post-TIPS values were comparatively low , which may be explained by the practice of broad-spectrum antibiotic administration in persons with acute variceal bleeding.
We found that the cirrhotic liver cleared 25% of the endotoxin present in the portal vein. The proportion of LPS that we measured in the central vein compared to the portal vein (52 ± 10%) compared closely with a previous analysis from Lumsden et al. 1988, who determined that 57% of portal LPS was cleared compared to the systemic circulation . In contrast, we analyzed for the first time the THEG between the portal vein and the hepatic vein directly pre- and post TIPS, which better reflects hepatic clearance due to absence of dilution from the systemic venous circulation. The THEG pre-TIPS was found to be 438 ± 287 pg/mL, and was remarkably similar between patients despite variable portal and hepatic vein LPS concentrations in the cohort. The pre-TIPS THEG we observed strongly indicates that the liver retains the capacity for portal blood detoxification even in the setting of cirrhosis, but this may be an underestimate of LPS clearance because cirrhosis is frequently associated with reversal of flow, spontaneous portosystemic shunting, and impaired clearance of bacteremia. Ideally it would be interesting to assess the same values in control patients without liver cirrhosis. However, this is practically challenging, since access to portal venous and hepatic venous blood is ethically justified only in persons with a clinical indication for TIPS placement.
LBP concentrations were not differentially enriched in the various blood compartments, suggesting that the transhepatic LPS gradient was not simply an artifact due to progressive hepatic vein dilution. Since LBP -in contrast to LPS- is not specifically cleared by Kupffer cells, LBP amounts were expected to be the same in the portal and hepatic veins. LBP is produced by hepatocytes, and circulating quantities may be diminished with extensive hepatic fibrosis and cirrhosis. Reduced LBP levels may impair LPS sensing systemically, since it is a key component of the TLR4 receptor complex. The negative immunologic consequences of reduced LPS sensing in the context of impaired LPS clearance potentially includes both poor innate immune surveillance with resulting bacterial infections, as well as reduced immunotolerance resulting in sepsis-like syndromes; both are known complications of end-stage liver disease.
Bacterial DNA concentrations were elevated in all patients, but the levels were not different in the hepatic and portal vein, suggesting that clearance of bacterial DNA and LPS occurs via different mechanisms. Markers of impaired intestinal permeability are elevated in portal hypertension, particularly with severe liver disease, and in viral and alcoholic cirrhosis [11, 32]. Circulating LPS levels have indeed been associated with extensive hepatic fibrosis in HCV and HBV infection [8, 11]. Therefore, although we observed an increase in hepatic venous and systemic endotoxemia in the short term, this may be reversed in the follow-up period after TIPS placement, since portal hypertension is reduced. In accordance, three studies observed reduction of surgical infections or peritonitis after lowering portal venous pressures [33–35]. Indeed, it is important to highlight that despite the patients' clinical status as having decompensated cirrhosis, we found that the liver retains the capacity to clear translocated bacterial products and that a decrease in this capacity post-TIPS implantation is associated with increased NO concentrations. Since no long-term peripheral endotoxin concentrations are available in our cohort of patients, future studies should focus on the potential improvement of endotoxemia and the incidence of infections after TIPS placement.
Endogenous NO is important for the integrity of the intestinal mucosa, whereas overproduction of NO, e.g. by inducible NO synthase (iNOS), impairs function of the intestinal epithelium, increases its permeability and leads to bacterial translocation and inflammatory responses [36, 37]. Further complicating inference of cause and effect, bacterial translocation and endotoxemia increase NO production in animal models of cirrhosis and in patients [23, 38, 39]. In accordance with a recent study focusing on hepatic clearance of NO synthase inhibitors , we found the highest values for L-arginine in the portal venous blood. Also, L-arginine concentrations in the hepatic vein and central venous blood increased after TIPS to a level as high as in the portal vein. In contrast, the endogenous NOS inhibitor ADMA was unaltered before and after TIPS. This increase in NO bioavailability after TIPS placement may be one of the factors contributing to the hyperdynamic state after TIPS placement. Whether this results solely from shunting through the TIPS or is a consequence of reduced cleareance of endotoxin by the liver remains unclear. It has been suggested that arginase-1 expressing, alternatively activated macrophages regulate collagen production and organ fibrosis . Whether the increased L-arginine, which serves as a substrate for arginase-1, is also involved in alteration of liver fibrosis is still unclear and needs to be studied in animal models . However, studies in cirrhotic patients demonstrated that intestinal decontamination with antibiotics is associated with less systemic endotoxemia and less NO-mediated vasodilatation [23, 43], thus indicating a potential link to the observed changes after TIPS placement. Since intestinal decontamination has recently shown to improve encephalopathy and prognosis in cirrhotic patients [44, 45], future studies should focus on the underlying pathophysiology including analysis of portal/systemic endotoxin and NO physiology in patients with cirrhosis. LPS concentrations should be correlated with clinical parameters and outcome, and clinical interventions should be tested to lower endotoxemia in patients undergoing TIPS, i.e. by application of prophylactic periinterventional or long-term antibiotics.
Taken together, this small pilot study demonstrates for the first time a significant transhepatic gradient of LPS and L-arginine in vivo, and immediate loss of this gradient following TIPS. These findings also suggest that measurements of microbial translocation from peripheral blood are likely to be both underestimates of intestinal translocation and significantly confounded by liver disease. The liver retains some capacity for LPS clearance even in cirrhosis, and bypassing hepatic LPS may increase the risk of infection after TIPS. In addition, future studies of microbial translocation must include assessment of liver function, particularly in studies of HIV-infected people in whom liver disease is a major cause of death .
Acknowledgements and financial support
The project described was supported by Grant Numbers BE2559/2-1, FFM (DB), SFB 841 A6 (JSzW) from Deutsche Forschungsgemeinschaft, FFM (JSzW), Werner Otto Stiftung (JSzW), K08 AI081544 (AB) from NIAID and R01 DA016078 (DT) from NIDA.
- Bigatello LM, Broitman SA, Fattori L, Di Paoli M, Pontello M, Bevilacqua G, Nespoli A: Endotoxemia, encephalopathy, and mortality in cirrhotic patients. Am J Gastroenterol. 1987, 82: 11-15.PubMedGoogle Scholar
- Scarpellini E, Valenza V, Gabrielli M, Lauritano EC, Perotti G, Merra G, Dal Lago A, Ojetti V, Ainora ME, Santoro M, et al: Intestinal permeability in cirrhotic patients with and without spontaneous bacterial peritonitis: is the ring closed?. Am J Gastroenterol. 2010, 105: 323-327. 10.1038/ajg.2009.558.View ArticlePubMedGoogle Scholar
- Wiest R, Garcia-Tsao G: Bacterial translocation (BT) in cirrhosis. Hepatology. 2005, 41: 422-433. 10.1002/hep.20632.View ArticlePubMedGoogle Scholar
- Howe LM, Boothe DM, Boothe HW: Endotoxemia associated with experimentally induced multiple portosystemic shunts in dogs. Am J Vet Res. 1997, 58: 83-88.PubMedGoogle Scholar
- Palma P, Mihaljevic N, Hasenberg T, Keese M, Koeppel TA: Intestinal barrier dysfunction in developing liver cirrhosis: An in vivo analysis of bacterial translocation. Hepatol Res. 2007, 37: 6-12. 10.1111/j.1872-034X.2007.00004.x.View ArticlePubMedGoogle Scholar
- Peterson SL, Koblik PD, Whiting PG, Breznock EM: Endotoxin concentrations measured by a chromogenic assay in portal and peripheral venous blood in ten dogs with portosystemic shunts. J Vet Intern Med. 1991, 5: 71-74. 10.1111/j.1939-1676.1991.tb00934.x.View ArticlePubMedGoogle Scholar
- Jacob AI, Goldberg PK, Bloom N, Degenshein GA, Kozinn PJ: Endotoxin and bacteria in portal blood. Gastroenterology. 1977, 72: 1268-1270.PubMedGoogle Scholar
- Balagopal A, Philp FH, Astemborski J, Block TM, Mehta A, Long R, Kirk GD, Mehta SH, Cox AL, Thomas DL, Ray SC: Human immunodeficiency virus-related microbial translocation and progression of hepatitis C. Gastroenterology. 2008, 135: 226-233. 10.1053/j.gastro.2008.03.022.View ArticlePubMedPubMed CentralGoogle Scholar
- Brenchley JM, Price DA, Schacker TW, Asher TE, Silvestri G, Rao S, Kazzaz Z, Bornstein E, Lambotte O, Altmann D, et al: Microbial translocation is a cause of systemic immune activation in chronic HIV infection. Nat Med. 2006, 12: 1365-1371.View ArticlePubMedGoogle Scholar
- Redd AD, Gray RH, Quinn TC: Is Microbial Translocation a Cause or Consequence of HIV Disease Progression?. J Infect Dis.
- Sandler NG, Koh C, Roque A, Eccleston JL, Siegel RB, Demino M, Kleiner DE, Deeks SG, Liang TJ, Heller T, Douek DC: Host Response to Translocated Microbial Products Predicts Outcomes of Patients With HBV or HCV Infection. Gastroenterology. 2011Google Scholar
- Balagopal A, Gama L, Franco V, Russell J, Smeaton L, Clements J, Thomas D, Ray S, Gupta A: Serum Inhibits Detection of Microbial Translocation in HIV-1 and SIV Infection: ACTG NWCS 319. 2011, [abstract 306], 18th Conference on Retroviruses and Opportunistic Infections, Boston, [http://www.retroconference.org/2011/PDFs/306.pdf]Google Scholar
- Afdhal NH, Curry MP: Early TIPS to improve survival in acute variceal bleeding. N Engl J Med. 2010, 362: 2421-2422. 10.1056/NEJMe1003400.View ArticlePubMedGoogle Scholar
- Luca A, Miraglia R, Caruso S, Milazzo M, Sapere C, Maruzzelli L, Vizzini G, Tuzzolino F, Gridelli B, Bosch J: Short- and long-term effects of the transjugular intrahepatic portosystemic shunt on portal vein thrombosis in patients with cirrhosis. Gut. 2011, 60: 846-852. 10.1136/gut.2010.228023.View ArticlePubMedGoogle Scholar
- Boyer TD, Haskal ZJ: The Role of Transjugular Intrahepatic Portosystemic Shunt (TIPS) in the Management of Portal Hypertension: update 2009. Hepatology. 2010, 51: 306-View ArticlePubMedGoogle Scholar
- Ochs A: Transjugular intrahepatic portosystemic shunt. Dig Dis. 2005, 23: 56-64. 10.1159/000084726.View ArticlePubMedGoogle Scholar
- Nolte W, Ehrenreich H, Wiltfang J, Pahl K, Unterberg K, Kamrowski-Kruck H, Schindler CG, Figulla HR, Buchwald AB, Hartmann H, Ramadori G: Systemic and splanchnic endothelin-1 plasma levels in liver cirrhosis before and after transjugular intrahepatic portosystemic shunt (TIPS). Liver. 2000, 20: 60-65. 10.1034/j.1600-0676.2000.020001060.x.View ArticlePubMedGoogle Scholar
- Jalan R, Olde Damink SW, Ter Steege JC, Redhead DN, Lee A, Hayes PC, Deutz NE: Acute endotoxemia following transjugular intrahepatic stent-shunt insertion is associated with systemic and cerebral vasodilatation with increased whole body nitric oxide production in critically ill cirrhotic patients. J Hepatol. 2011, 54: 265-271. 10.1016/j.jhep.2010.06.042.View ArticlePubMedGoogle Scholar
- Bellot P, Garcia-Pagan JC, Frances R, Abraldes JG, Navasa M, Perez-Mateo M, Such J, Bosch J: Bacterial DNA translocation is associated with systemic circulatory abnormalities and intrahepatic endothelial dysfunction in patients with cirrhosis. Hepatology. 2010, 52: 2044-2052. 10.1002/hep.23918.View ArticlePubMedGoogle Scholar
- Won H, Rothman R, Ramachandran P, Hsieh YH, Kecojevic A, Carroll KC, Aird D, Gaydos C, Yang S: Rapid identification of bacterial pathogens in positive blood culture bottles by use of a broad-based PCR assay coupled with high-resolution melt analysis. J Clin Microbiol. 2010, 48: 3410-3413. 10.1128/JCM.00718-10.View ArticlePubMedPubMed CentralGoogle Scholar
- Yang S, Lin S, Kelen GD, Quinn TC, Dick JD, Gaydos CA, Rothman RE: Quantitative multiprobe PCR assay for simultaneous detection and identification to species level of bacterial pathogens. J Clin Microbiol. 2002, 40: 3449-3454. 10.1128/JCM.40.9.3449-3454.2002.View ArticlePubMedPubMed CentralGoogle Scholar
- Schwedhelm E, von Leitner EC, Atzler D, Schmitz C, Jacobi J, Meinertz T, Munzel T, Baldus S, Cooke JP, Boger RH, et al: Extensive characterization of the human DDAH1 transgenic mice. Pharmacol Res. 2009, 60: 494-502. 10.1016/j.phrs.2009.08.001.View ArticlePubMedGoogle Scholar
- Guarner C, Soriano G, Tomas A, Bulbena O, Novella MT, Balanzo J, Vilardell F, Mourelle M, Moncada S: Increased serum nitrite and nitrate levels in patients with cirrhosis: relationship to endotoxemia. Hepatology. 1993, 18: 1139-1143. 10.1002/hep.1840180520.View ArticlePubMedGoogle Scholar
- Triger DR, Boyer TD, Levin J: Portal and systemic bacteraemia and endotoxaemia in liver disease. Gut. 1978, 19: 935-939. 10.1136/gut.19.10.935.View ArticlePubMedPubMed CentralGoogle Scholar
- Van Leeuwen PA, Boermeester MA, Houdijk AP, Ferwerda CC, Cuesta MA, Meyer S, Wesdorp RI: Clinical significance of translocation. Gut. 1994, 35: S28-34.View ArticlePubMedPubMed CentralGoogle Scholar
- Balagopal A, Ray SC, De Oca RM, Sutcliffe CG, Vivekanandan P, Higgins Y, Mehta SH, Moore RD, Sulkowski MS, Thomas DL, Torbenson MS: Kupffer cells are depleted with HIV immunodeficiency and partially recovered with antiretroviral immune reconstitution. Aids. 2009, 23: 2397-2404. 10.1097/QAD.0b013e3283324344.View ArticlePubMedPubMed CentralGoogle Scholar
- Lumsden AB, Henderson JM, Kutner MH: Endotoxin levels measured by a chromogenic assay in portal, hepatic and peripheral venous blood in patients with cirrhosis. Hepatology. 1988, 8: 232-236. 10.1002/hep.1840080207.View ArticlePubMedGoogle Scholar
- Lin RS, Lee FY, Lee SD, Tsai YT, Lin HC, Lu RH, Hsu WC, Huang CC, Wang SS, Lo KJ: Endotoxemia in patients with chronic liver diseases: relationship to severity of liver diseases, presence of esophageal varices, and hyperdynamic circulation. J Hepatol. 1995, 22: 165-172. 10.1016/0168-8278(95)80424-2.View ArticlePubMedGoogle Scholar
- von Baehr V, Docke WD, Plauth M, Liebenthal C, Kupferling S, Lochs H, Baumgarten R, Volk HD: Mechanisms of endotoxin tolerance in patients with alcoholic liver cirrhosis: role of interleukin 10, interleukin 1 receptor antagonist, and soluble tumour necrosis factor receptors as well as effector cell desensitisation. Gut. 2000, 47: 281-287. 10.1136/gut.47.2.281.View ArticlePubMedPubMed CentralGoogle Scholar
- Fukui H, Matsumoto M, Tsujita S, Takaya A, Kojima H, Matsumura M, Tsujii T: Plasma endotoxin concentration and endotoxin binding capacity of plasma acute phase proteins in cirrhotics with variceal bleeding: an analysis by new methods. J Gastroenterol Hepatol. 1994, 9: 582-586. 10.1111/j.1440-1746.1994.tb01565.x.View ArticlePubMedGoogle Scholar
- Goulis J, Armonis A, Patch D, Sabin C, Greenslade L, Burroughs AK: Bacterial infection is independently associated with failure to control bleeding in cirrhotic patients with gastrointestinal hemorrhage. Hepatology. 1998, 27: 1207-1212. 10.1002/hep.510270504.View ArticlePubMedGoogle Scholar
- Campillo B, Pernet P, Bories PN, Richardet JP, Devanlay M, Aussel C: Intestinal permeability in liver cirrhosis: relationship with severe septic complications. Eur J Gastroenterol Hepatol. 1999, 11: 755-759. 10.1097/00042737-199907000-00013.View ArticlePubMedGoogle Scholar
- Perez-Paramo M, Munoz J, Albillos A, Freile I, Portero F, Santos M, Ortiz-Berrocal J: Effect of propranolol on the factors promoting bacterial translocation in cirrhotic rats with ascites. Hepatology. 2000, 31: 43-48. 10.1002/hep.510310109.View ArticlePubMedGoogle Scholar
- Xu WH, Wu XJ, Li JS: Influence of portal pressure change on intestinal permeability in patients with portal hypertension. Hepatobiliary Pancreat Dis Int. 2002, 1: 510-514.PubMedGoogle Scholar
- Senzolo M, Fries W, Buda A, Pizzuti D, Nadal E, Sturniolo GC, Burroughs AK, D'Inca R: Oral propranolol decreases intestinal permeability in patients with cirrhosis: another protective mechanism against bleeding?. Am J Gastroenterol. 2009, 104: 3115-3116. 10.1038/ajg.2009.457.View ArticlePubMedGoogle Scholar
- Alican I, Kubes P: A critical role for nitric oxide in intestinal barrier function and dysfunction. Am J Physiol. 1996, 270: G225-237.PubMedGoogle Scholar
- Unno N, Wang H, Menconi MJ, Tytgat SH, Larkin V, Smith M, Morin MJ, Chavez A, Hodin RA, Fink MP: Inhibition of inducible nitric oxide synthase ameliorates endotoxin-induced gut mucosal barrier dysfunction in rats. Gastroenterology. 1997, 113: 1246-1257. 10.1053/gast.1997.v113.pm9322519.View ArticlePubMedGoogle Scholar
- Wiest R, Das S, Cadelina G, Garcia-Tsao G, Milstien S, Groszmann RJ: Bacterial translocation in cirrhotic rats stimulates eNOS-derived NO production and impairs mesenteric vascular contractility. J Clin Invest. 1999, 104: 1223-1233. 10.1172/JCI7458.View ArticlePubMedPubMed CentralGoogle Scholar
- Wiest R, Cadelina G, Milstien S, McCuskey RS, Garcia-Tsao G, Groszmann RJ: Bacterial translocation up-regulates GTP-cyclohydrolase I in mesenteric vasculature of cirrhotic rats. Hepatology. 2003, 38: 1508-1515.View ArticlePubMedGoogle Scholar
- Siroen MP, Wiest R, Richir MC, Teerlink T, Rauwerda JA, Drescher FT, Zorger N, van Leeuwen PA: Transjugular intrahepatic portosystemic shunt-placement increases arginine/asymmetric dimethylarginine ratio in cirrhotic patients. World J Gastroenterol. 2008, 14: 7214-7219. 10.3748/wjg.14.7214.View ArticlePubMedPubMed CentralGoogle Scholar
- Wynn TA, Barron L: Macrophages: master regulators of inflammation and fibrosis. Semin Liver Dis. 2010, 30: 245-257. 10.1055/s-0030-1255354.View ArticlePubMedPubMed CentralGoogle Scholar
- Pesce JT, Ramalingam TR, Mentink-Kane MM, Wilson MS, El Kasmi KC, Smith AM, Thompson RW, Cheever AW, Murray PJ, Wynn TA: Arginase-1-expressing macrophages suppress Th2 cytokine-driven inflammation and fibrosis. PLoS Pathog. 2009, 5: e1000371-10.1371/journal.ppat.1000371.View ArticlePubMedPubMed CentralGoogle Scholar
- Rasaratnam B, Kaye D, Jennings G, Dudley F, Chin-Dusting J: The effect of selective intestinal decontamination on the hyperdynamic circulatory state in cirrhosis. A randomized trial. Ann Intern Med. 2003, 139: 186-193.View ArticlePubMedGoogle Scholar
- Bass NM, Mullen KD, Sanyal A, Poordad F, Neff G, Leevy CB, Sigal S, Sheikh MY, Beavers K, Frederick T, et al: Rifaximin treatment in hepatic encephalopathy. N Engl J Med. 2010, 362: 1071-1081. 10.1056/NEJMoa0907893.View ArticlePubMedGoogle Scholar
- Vlachogiannakos J, Viazis N, Vasianopoulou P, Vafiadis-Zouboulis I, Karamanolis DG, Ladas SD: Long-term administration of rifaximin improves the prognosis of patients with alcohol-related decompensated cirrhosis: A case control study. Hepatology. 2010, 52: 328A-Google Scholar
- Weber R, Sabin CA, Friis-Moller N, Reiss P, El-Sadr WM, Kirk O, Dabis F, Law MG, Pradier C, De Wit S, et al: Liver-related deaths in persons infected with the human immunodeficiency virus: the D:A:D study. Arch Intern Med. 2006, 166: 1632-1641.View ArticlePubMedGoogle Scholar
- The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-230X/11/107/prepub
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.