Sensitivity and specificity of bispectral index for classification of overt hepatic encephalopathy: a multicentre, observer blinded, validation study.

BACKGROUND: The severity of hepatic encephalopathy is currently graded clinically using West Haven criteria and psychometric tests. OBJECTIVE: To assess the discriminative power of the bispectral index (BIS) monitor to classify the degree and progression of hepatic encephalopathy. DESIGN: A consecutive, multicentre, observer blinded validation study. SETTING: Medical University of Graz (Graz, Austria), Zhejiang University First Affiliated Hospital (Hang Zhou, China), and Cairo University (Cairo, Egypt). PATIENTS: 28 consecutive patients with hepatic encephalopathy were first enrolled at Medical University of Graz as a test set. The estimated BIS cut off values were subsequently tested in a validation set of 31 patients at Zhejiang University First Affiliated Hospital and 26 patients at Cairo University; 18 patients were reassessed later in a longitudinal study. Fifteen of 85 patients (18%) were excluded from the final analysis (11 became too agitated with high electromyographic activity; four fell asleep during the recording). RESULTS: Applying the Austrian BIS cut off values of 85, 70, and 55 for discriminating West Haven grades 1 to 4 yielded agreement between BIS classification and West Haven grades in 40 of the 46 validation patients (87%), and in 16 of the 18 follow up patients (89%). Mean (SD) BIS values differed significantly between patients with West Haven grade 1 (90.2 (2.5)), grade 2 (78.4 (6.6)), grade 3 (63.2 (4.8)), and grade 4 (45.4 (5.0)). CONCLUSIONS: BIS is a useful measure for grading and monitoring the degree of involvement of the central nervous system in patients with chronic liver disease.

Albumin infusion fails to restore circulatory function following paracentesis of tense ascites as assessed by beat-to-beat haemodynamic measurements.

AIMS: To study whether circulatory changes during large volume paracentesis (LVP) in patients with liver cirrhosis and tense ascites as assessed by novel non-invasive haemodynamic measuring technology are reversed by subsequent albumin infusion. MATERIALS AND METHODS: Eleven patients with portal hypertensive ascites secondary to liver cirrhosis of Child's class B or C were studied during LVP (10.7 +/- 4.4 l) and subsequent infusion of albumin. Digital arterial pulse waves were continuously measured by vascular unloading technique providing data for beat-to-beat values of systolic (P(s)), diastolic (P(d)) and mean arterial pressures (P(m)), respectively, as well as for heart rate (F(h)), stroke volume (V(s)), cardiac output (Q(co)) and peripheral resistance (R). Data extrapolated to the end of paracentesis, albumin infusion and follow-up phases were compared with the end of the equilibration phase. RESULTS: At the end of paracentesis, P(s), P(m) and P(d) changed by -14 +/- 15% (p < 0.05), -16 +/- 11% (p < 0.01) and -17 +/- 11% (p < 0.001), respectively, whereas Q(co) and F(h) did not change substantially. There was a highly significant increase in V(s) by +21 +/- 25% (p < 0.01). The largest change was seen in R which significantly decreased by -29 +/- 24% (p < 0.01). This change was not reversed by infusion of albumin and persisted up to the end of follow-up. CONCLUSION: The haemodynamic changes following LVP appear to be first and foremost controlled by changes in peripheral resistance with insufficient cardiac compensation. Further studies combining albumin with vasopressors for prevention of paracentesis-induced circulatory changes are needed.

Soluble CD163 and soluble mannose receptor predict survival and decompensation in patients with liver cirrhosis, and correlate with gut permeability and bacterial translocation.

BACKGROUND: Activated hepatic macrophages play a key role in inflammation and fibrosis progression in chronic liver disease. AIM: To assess the prognostic value of soluble (s)CD163 and mannose receptor (sMR) in cirrhotic patients and explore associations with markers of intestinal permeability (lactulose-mannitol ratio, diamine oxidase), bacterial translocation (endotoxin, lipopolysaccharide-binding protein) and markers of systemic immune activation (interleukin-6, interleukin-8, sCD14). METHODS: We prospectively investigated 101 cirrhotic patients (Child-Pugh class A: n = 72, Child-Pugh classes B and C: n = 29) and 31 healthy controls. Patients were observed for a median follow-up of 37 months. RESULTS: Median plasma levels of sCD163 and soluble mannose receptor were significantly elevated in cirrhotic patients (P < .001) and increased with disease severity (sCD163 in healthy controls = 1.3, Child-Pugh class A = 4.2, Child-Pugh classes B and C = 8.4 mg/L; sMR in healthy controls = 15.8, Child-Pugh class A = 36.5, Child-Pugh classes B and C = 66.3 µg/dL). A total of 21 patients died during the observation period. Patients with sCD163 levels above 5.9 mg/L showed significantly reduced survival (survival rate after 36 months: 71% versus 98%, P < .001). Patients with soluble mannose receptor levels above 45.5 µg/dL developed significantly more complications of cirrhosis within 12 months (73% versus 9%, P < .001). Furthermore, both variables correlated with the lactulose-mannitol ratio, diamine oxidase, lipopolysaccharide and interleukin-8. CONCLUSION: Our data demonstrate the prognostic value of sCD163 in predicting long-term survival in patients with liver cirrhosis and identify soluble mannose receptor as a prognostic marker for occurrence of cirrhosis-associated complications. The correlation between gut barrier dysfunction and activation of macrophages points towards a link between them.

Physiological and pathological changes in the redox state of human serum albumin critically influence its binding properties.

Binding and transport of a number of endogenous and exogenous compounds is an important function of the main plasma protein, albumin. In vivo and in vitro, albumin may be oxidatively modified in different ways with different agents at different sites. These modifications have various consequences on the physiological functions of albumin. Diabetes mellitus, liver diseases and nephropathy are just a few examples of disorders in which oxidative stress is involved and altered albumin functions have been described. This review is focussed on the consequences of oxidative modification on the binding properties of albumin. These range from no effect to decreased or increased binding affinities depending on the ligand under investigation and the type of modification. Indicators for modification include glycosylation, disulphide formation or the content of carbonyl groups. The redox state of albumin can affect the binding properties in several ways, including altered conformation and consequently altered affinities at binding sites and altered binding when the binding reaction itself is redox sensitive. The physiological or pathophysiological concentrations of different oxidatively modified albumin molecules vary over a wide range and are crucial in assessing the clinical relevance of altered ligand binding properties of a particularly modified albumin species in various disease conditions.

Randomised clinical trial: the effects of a multispecies probiotic vs. placebo on innate immune function, bacterial translocation and gut permeability in patients with cirrhosis.

BACKGROUND: Probiotics may correct intestinal dysbiosis and proinflammatory conditions in patients with liver cirrhosis. AIM: To test the effects of a multispecies probiotic on innate immune function, bacterial translocation and gut permeability. METHODS: In a randomised, double blind, placebo-controlled study, stable cirrhotic out-patients either received a daily dose of a probiotic powder containing eight different bacterial strains (Ecologic Barrier, Winclove, Amsterdam, The Netherlands) (n = 44) or a placebo (n = 36) for 6 months and were followed up for another 6 months. RESULTS: We found a significant but subclinical increase in neutrophil resting burst (2.6-3.2%, P = 0.0134) and neopterin levels (7.7-8.4 nmol/L, P = 0.001) with probiotics but not with placebo. Probiotic supplementation did not have a significant influence on neutrophil phagocytosis, endotoxin load, gut permeability or inflammatory markers. Ten severe infections occurred in total; one during intervention in the placebo group, and five and four after the intervention has ended in the probiotic and placebo group, respectively. Liver function showed some improvement with probiotics but not with placebo. CONCLUSIONS: Probiotic supplementation significantly increased serum neopterin levels and the production of reactive oxygen species by neutrophils. These findings might explain the beneficial effects of probiotics on immune function. Furthermore, probiotic supplementation may be a well-tolerated method to maintain or even improve liver function in stable cirrhosis. However, its influence on gut barrier function and bacterial translocation in cirrhotic patients is minimal.

Nitric oxide-dependent and -independent vascular hyporeactivity in mesenteric arteries of portal hypertensive rats.

1. Increased production of nitric oxide (NO) has been suggested to underlie both the vascular hyporeactivity to vasoconstrictors and the splanchnic vasodilatation seen in portal hypertension. This study assessed the role of NO in the vasoconstrictor hyporeactivity of portal vein-ligated (PVL) rats in isolated and in situ perfused mesenteric arterial beds. 2. Isolated perfused mesenteric arteries of PVL rats were significantly less reactive to noradrenaline (NA), methoxamine (METH), arginine vasopressin (AVP) and endothelin-1 (ET-1) than those from sham-operated (Sham) rats. 3. Blockade of NO synthesis with NG-nitro-L-arginine methyl ester (L-NAME, 100 microM) in isolated perfused mesenteric arteries from PVL rats restored the reactivity to bolus injections of AVP and ET-1, but had little effect on the hyporeactivity to NA or METH. Cyclo-oxygenase inhibition with indomethacin (5 microM) likewise did not restore reactivity to METH of isolated perfused mesenteric arteries of PVL rats. 4. The hyporeactivity to METH seen in isolated perfused mesenteric arteries from PVL rats was reduced by low concentrations of AVP (20 nM) or ET-1 (1 nM) which per se caused only a slight increase in perfusion pressure. When L-NAME (100 microM) was combined with AVP (20 nM) or ET-1 (1 nM), respectively, reactivity to METH of isolated perfused mesenteric arteries of PVL rats was restored to the level seen in Sham rats. These effects of AVP and ET-1 were not mimicked by precontracting the vessels with 5-hydroxytryptamine (5 microM). 5. The differential effects of L-NAME and AVP on the hyporesponsiveness to methoxamine and AVP were corroborated by experiments performed with the in situ perfused mesenteric vascular bed preparation. 6. These data indicate that both NO-dependent and NO-dependent mechanisms are involved in the vasoconstrictor hyporesponsiveness of mesenteric arteries from portal hypertensive rats. The hyporeactivity to AVP and ET-1 is mediated by NO whereas the reduced responsiveness to adrenoceptor agonists appears to be predominantly NO-independent AVP and ET-1, in addition, seem to inhibit the NO-independent mechanism of vascular hyporeactivity, since the hyporesponsiveness to METH was reduced in the presence of AVP or ET-1 and abolished by the combination of these peptides with L-NAME.

Lack of effect of a selective vasopressin V1A receptor antagonist SR 49,059, on potentiation by vasopressin of adrenoceptor-mediated pressor responses in the rat mesenteric arterial bed.

The vasopressin receptor subtype involved in the enhancement by vasopressin of adrenoceptor-mediated vasoconstriction was investigated in rat isolated perfused mesenteric arteries. [Arg8]vasopressin (1-10 nM) dose-dependently increased the perfusion pressure and enhanced the pressor response to the adrenoceptor agonist methoxamine (40 nmol) or electrical stimulation of periarterial nerves (16 Hz), at the concentration of 10 nM of [Arg8]vasopressin up to 4 and 3 fold, respectively. During prolonged exposure (45 min) the direct vasoconstrictor effect of [Arg8]vasopressin (10 nM) rapidly declined whereas the potentiation of methoxamine-induced vasoconstriction was maintained. The selective vasopressin V1A receptor antagonist SR 49,059 (1-3 nM) and the non-selective V1A/B and oxytocin receptor antagonist [deamino-Pen1,Tyr(Me)2,Arg8]vasopressin (15-45 nM) inhibited the direct vasoconstrictor action of [Arg8]vasopressin but had no effect on the enhancement of the pressor response to methoxamine or electrical stimulation. The V1B receptor agonist [deamino-Cys1,beta-(3-pyridyl)-D-Ala2,Arg8]vasopressin (100-1000 nM) and the V2 receptor agonist [deamino-Cys1,D-Arg8]vasopressin (1-10 nM) were devoid of any pressor activity and did not potentiate methoxamine-evoked vasoconstriction. In contrast, [1-triglycyl,Lys8]vasopressin (100 - 1000 nM) potentiated the methoxamine responses without per se inducing vasoconstriction. In arteries precontracted with methoxamine (7.5 microM) pressor responses to [Arg8]vasopressin (3-10 nM) were not inhibited by a dose of SR 49,059 (3 nM) which abolished the peptide's vasoconstrictor effect under control conditions. These data show that the direct vasoconstrictor effect of [Arg8]vasopressin is mediated by V1A receptors while the enhancement of adrenoceptor-mediated pressor responses is insensitive to V1A, V1B, and oxytocin receptor antagonists and is not mimicked by selective agonists of V1B and V2 receptors. In conclusion, an unusual interaction of vasopressin with V1A receptors, or even the existence of a novel receptor subtype, has to be considered.

The role of inducible nitric oxide synthase in vascular hyporeactivity of endotoxin-treated and portal hypertensive rats.

The involvement of the inducible nitric oxide (NO) synthase in the vascular hyporeactivity in portal vein-ligated rats was assessed in isolated perfused mesenteric arterial beds. Aminoguanidine, a selective inhibitor of the inducible NO synthase, restored the pressor responses to methoxamine in arteries of endotoxin-treated rats, but was ineffective in hyporeactive portal vein-ligated vessels. NG-Nitro-L-arginine methyl ester enhanced the responsiveness both in portal vein-ligated and sham-operated rats, without changing the difference between the two groups. These results not only indicate that the inducible NO synthase is not involved in the hyporeactivity to methoxamine in mesenteric arteries of portal hypertensive rats, but also suggest a role for factors other than NO.

Intra-hepatic haematoma complicating transjugular intra-hepatic portosystemic shunt for Budd-Chiari syndrome associated with anti-phospholipid antibodies, aplastic anaemia and chronic hepatitis C.

Portal venous decompression with transjugular intra-hepatic portosystemic shunt (TIPS) is a new approach in the treatment of Budd-Chiari syndrome. We report on a 31-year-old female with Budd-Chiari syndrome due to anti-phospholipid antibodies with compression of the inferior vena cava treated with TIPS and stenting of the inferior vena cava. TIPS was complicated by massive intra-hepatic haematoma which was managed conservatively. Treatment options and pathogenic mechanisms of Budd-Chiari syndrome under the rare coincidence of aplastic anaemia and anti-phospholipid syndrome are discussed. TIPS may be considered for venous decompression in Budd-Chiari syndrome, but physicians should be aware of potential TIPS' complications in these patients.

Hepatocellular bile salt transport: lessons from cholestasis.

Hepatic uptake and excretion of bile salts and several nonbile salt organic anions (eg, bilirubin) are mediated by a distinct set of polarized transport systems at the basolateral and apical plasma membrane domains of hepatocytes and bile duct epithelial cells (cholangiocytes). With the increasing availability of molecular probes for these transporters, evidence now exists that decreased or even absent expression of hepatobiliary transport proteins in hepatocytes or cholangiocytes may explain impaired transport function that results in hyperbilirubinemia and cholestasis. This review summarizes the molecular defects in hepatocellular membrane transporters that are associated with hereditary and acquired forms of cholestatic liver disease.

The use of quantitative scintigraphy in the measurement of portal-systemic shunting in rats.

Portal-systemic shunting was studied in 54 portal hypertensive rats both in vivo and in vitro using radioactive microspheres. The animals underwent partial portal vein ligation around needles of varying diameter to produce a wide range of shunting. Two to four weeks later, quantitative lung-liver scintigraphic and whole body images were obtained in vivo following ileocolic vein injection with 99mTc-MAA. After sacrifice, the lung and liver activities were determined by the gamma camera, a dose calibrator, and a well counter. Portal-systemic shunting ranged from 0.1-97.6%. When shunting was compared in vivo and in vitro, an excellent correlation was found (r = 0.99, p < 0.001). A subgroup of 24 animals had consecutive injections of 99mTc-MAA and 51Cr-labeled 15 microns microspheres, which, although different in size, yielded similar results (r = 0.89, p < 0.001). We conclude that in small laboratory animals a wide range of shunting can be measured accurately in vivo by quantitative scintigraphy.

Hepatitis C virus-specific T cell responses against conserved regions in recovered patients.

For the design of peptide-based vaccines against the hepatitis C virus it is essential to acquire more information on frequently recognized epitopes in patients with successful immune control of HCV in the context of different HLA types. A matrix approach using 393 15mer peptides from conserved HCV regions overlapping by 13 amino acids was applied in 52 HCV-recovered individuals. Candidate peptides were further tested in two independent laboratories. 38 peptides induced IFN-gamma responses in ELISPOT assays including 15 previously unknown epitopes. There was no particular immune dominance as only five peptides were recognized by more than three individuals. Seven out of 14 peptides tested in more detail could be confirmed to be immunogenic using ELISPOT and cytotoxicity assays. While only 33% of HCV-recovered individuals recognized recombinant HCV proteins, 81% of individuals tested positive in the matrix approach (p<0.001). The strength, frequency and breadth of HCV-specific T cell responses were similar in spontaneously recovered patients than in interferon-recovered patients. In conclusion (i) we identified novel HCV epitopes in conserved regions, (ii) confirmed the inter-individual diversity of HCV-specific T cell responses and (iii) found no significant differences in HCV-specific T cell responses between spontaneously recovered and IFN-recovered patients.

Vasodilator responses to nitric oxide are enhanced in mesenteric arteries of portal hypertensive rats.

Nitric oxide (NO) is discussed as a mediator of the splanchnic hyperaemia in portal hypertension. We assessed the vasorelaxation by the NO-dependent vasodilator acetylcholine, the NO donor 3-morpholino-sydnonimine (SIN-1) and forskolin, a stimulator of the adenylate cyclase pathway in potassium-preconstricted isolated perfused mesenteric arteries of portal vein-ligated and sham-operated rats. Dilator responses to acetylcholine and SIN-1 were significantly enhanced in vessels of portal vein-ligated rats as compared to sham-operated rats, whereas no difference was found in forskolin-induced vasodilatation. This suggests enhanced reactivity of the vasculature to NO in experimental portal hypertension.

Propranolol stereoselectively inhibits alpha-adrenoceptor-mediated vasoconstriction in mesenteric arterial beds of rats.

1. The optical isomers of propranolol were compared for their effects on pressor responses to adrenergic and non-adrenergic vasoconstrictors in mesenteric arterial beds of rats. 2. R(+)-propranolol (10(-7)-10(-5) M) had no effect on vessel preparations stimulated with noradrenaline, methoxamine, or arginine-vasopressin. 3. S(-)-propranolol 10(-7) M did not alter pressor responses to noradrenaline. However, S(-)-propranolol 10(-6) and 10(-5) M inhibited vasoconstriction induced by noradrenaline. This effect was similar in the presence of indomethacin 3 x 10(-6) M. 4. S(-)-propranolol 10(-5) M also inhibited vasoconstriction induced by methoxamine, shifting the dose-response curves to the right, but did not affect pressor responses to arginine-vasopressin. 5. Schild analysis for equilibrium vasoconstrictor responses to methoxamine indicated stereoselective competitive alpha-adrenoceptor antagonism by propranolol. 6. These data suggest selective inhibition of alpha-adrenoceptor-mediated vasoconstriction by S(-)-propranolol at higher concentrations by competitive alpha-adrenoceptor antagonism.

Effect of terlipressin on in vitro vascular hyporeactivity of portal hypertensive rats.

BACKGROUND/AIMS: Isolated vessels of portal hypertensive rats exhibit decreased responsiveness to vasoconstrictors. The vasopressin analogue terlipressin is used in the treatment of portal hypertension since it is known to reduce portal pressure, an effect that is thought to arise from splanchnic vasoconstriction via stimulation of vasoconstrictor V1 receptors. This study assessed the effect of terlipressin on the in vitro vascular reactivity of portal hypertensive rats to the alpha-adrenoceptor agonist methoxamine. METHODS: Portal hypertension was produced by portal vein ligation. Sham-operated rats served as controls. In isolated perfused mesenteric arteries of portal vein ligated and sham-operated rats pressor responses to methoxamine (3 nmol-3 mumol) were determined in the absence and presence of the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME; 100 microM), terlipressin or the selective V2 receptor agonist desmopressin (each 0.5 microM). In addition, the direct pressor properties of terlipressin (3 pmol-100 nmol) were compared to arginine vasopressin (3 pmol-1 nmol) in vessels of normal rats. RESULTS: Mesenteric vessels of portal vein ligated rats were markedly hyporeactive to methoxamine, even in the presence of L-NAME. Terlipressin alone reduced and in combination with L-NAME abolished the difference in reactivity to methoxamine between the portal vein ligated and sham-operated groups, while desmopressin was ineffective. Arginine vasopressin potently contracted vessels of normal rats with a threshold dose of 10 pmol and was maximally effective at 300 pmol. In contrast, terlipressin failed to produce pressor responses up to 100 nmol. CONCLUSIONS: Hyporeactivity of mesenteric vessels of portal vein ligated rats to methoxamine is predominantly independent of nitric oxide. Terlipressin alone ameliorates and in combination with L-NAME abolishes the hyporesponsiveness to methoxamine presumably by inhibiting the nitric oxide-independent mechanism that underlies the reduced responsiveness to methoxamine in portal hypertension. This effect of terlipressin appears to be independent of stimulation of V2 as well as vasoconstrictor V1 receptors.

Increased carbohydrate-deficient transferrin during pregnancy: relation to sex hormones.

Controversy exists whether carbohydrate-deficient transferrin (CDT) is valuable as a screening tool for fetal alcohol syndrome. We evaluated serum CDT in 60 non-alcohol-abusing women at different stages of normal pregnancy. CDT was weakly related to week of pregnancy and to human placental lactogen. CDT did not correlate with iron oestradiol or progesterone. By contrast, good correlations were found between transferrin and week of pregnancy or either sex hormone. Using multiple linear regression analysis, only transferrin and week of pregnancy were important predictors of CDT. The diagnostic accuracy of CDT for detecting alcohol abuse may be limited in pregnant women and should be carefully assessed in relation to alcohol consumption.

Inflammation-induced cholestasis.

Inflammatory cytokines produced in response to various infectious and non-infectious stimuli are potent inducers of intrahepatic cholestasis (inflammation-induced cholestasis). The cholestatic effect of cytokines results mainly from inhibition of expression and function of hepatocellular transport systems which normally mediate hepatic uptake and biliary excretion of bile salts and various non-bile salt organic anions (e.g. bilirubin). These cytokine effects are reversible and bile secretory function is restored upon disappearance of the inflammatory injury. This review summarizes the clinical, pathophysiological and molecular aspects of inflammation-induced cholestasis.

[New molecular aspects of cholestatic liver diseases]. / Neue molekulare Aspekte cholestatischer Lebererkrankungen.

Hepatic uptake and biliary excretion of bile salts and non-bile salt organic anions (e.g., bilirubin) is mediated by specific transport proteins located at the basolateral and canalicular membranes of hepatocytes. Several hepatobiliary transport systems have been identified and cloned over the past years. This development has facilitated molecular biological and genetic analyses of these transporters in experimental cholestasis and human cholestatic liver diseases. Evidence now exists that decreased or even absent expression of hepatobiliary transport systems may explain impaired transport function resulting in hyperbilirubinemia and cholestasis. This review summarizes the molecular defects in hepatocellular membrane transporters associated with hereditary and acquired forms of cholestatic liver diseases. The increasing information on the molecular regulation of hepatobiliary transport systems should bring new insights into the pathophysiology and treatment of human cholestatic liver diseases.

Evidence for modulation of hepatic mass by estrogens and hepatic "feminization".

Animals with end-to-side portacaval shunts and sham-operated animals, wherein the body weight and liver weight of the animals varied spontaneously over a considerable range, were studied. The relationships between hepatic androgen- and estrogen-receptor content, serum testosterone and estradiol levels and hepatic mass were characterized. Animals with portacaval shunts were smaller than those without shunts. Moreover, they had reduced serum levels of testosterone and estradiol. The reduction in serum testosterone was greater than that of estradiol. As a result, the calculated estrogen/testosterone ratio of the two groups of animals was greater for the portacaval shunt animals than for the controls. The dissociation constant values for the androgen receptor and estrogen receptor in the liver did not differ between groups. The activity of the androgen receptor (p less than 0.01) and estrogen receptor (p less than 0.05) was reduced markedly in the animals with portacaval shunts compared with controls. Moreover, the hepatic cytosolic estrogen receptor activity--but not that of the androgen receptor--correlated with the measured hepatic mass in both groups of animals. These data suggest that hepatic feminization is either associated with or is a hepatic regenerative signal in the rat.