Outcome in Caucasian patients with hepatitis B e antigen negative chronic infection: A long-term observational cohort study

Sensitive polymerase chain reaction assays to measure hepatitis B virus (HBV) DNA became only available the last decade. Hence, the long-term outcome of Caucasian patients in Western Europe with hepatitis B e antigen (HBeAg)-negative chronic infection, especially with a baseline HBV DNA level ⩾2000 IU/mL, is still unclear. Out of a cohort of 1936 chronic HBV patients, 413 Caucasian individuals were identified with HBeAg-negative chronic infection, defined as persistently normal alanine aminotransferase (ALT) levels and HBV DNA levels <20 000 IU/mL. During a mean follow-up of 12 years, 366 (88.6%) maintained an HBeAg-negative chronic infection status, whereas 25 (6.1%) developed chronic active hepatitis (CAH). In total, Nine of these 25 CAH cases were related to immunosuppression. In total, 22 (5.3%) individuals had ALT > 2 × upper limit of normal due to non-HBV-related causes. The cumulative probability of spontaneously developing CAH after 10 years was almost exclusively seen in patients with baseline HBV DNA level ⩾2000 IU/mL (11.7% vs 1.2%; P < .001). Advanced liver disease developed significantly more in patients with baseline HBV DNA level ⩾2000 IU/mL (5.2% vs 1.5%; P = .018) and occurred especially in patients with obesity (16.7% vs 4.2%; P = .049). The incidence of hepatocellular carcinoma was 0.0%. Caucasian patients with HBeAg-negative chronic infection and baseline HBV DNA level <2000 IU/mL have an excellent long-term prognosis in the absence of immunosuppressive therapy. However, patients with baseline HBV DNA level ⩾2000 IU/mL are at risk to develop advanced liver disease.

Patient Age, Sex, and Inflammatory Bowel Disease Phenotype Associate With Course of Primary Sclerosing Cholangitis

BACKGROUND & AIMS

Primary sclerosing cholangitis (PSC) is an orphan hepatobiliary disorder associated with inflammatory bowel disease (IBD). We aimed to estimate the risk of disease progression based on distinct clinical phenotypes in a large international cohort of patients with PSC.

METHODS

We performed a retrospective outcome analysis of patients diagnosed with PSC from 1980 through 2010 at 37 centers in Europe, North America, and Australia. For each patient, we collected data on sex, clinician-reported age at and date of PSC and IBD diagnoses, phenotypes of IBD and PSC, and date and indication of IBD-related surgeries. The primary and secondary endpoints were liver transplantation or death (LTD) and hepatopancreatobiliary malignancy, respectively. Cox proportional hazards models were applied to determine the effects of individual covariates on rates of clinical events, with time-to-event analysis ascertained through Kaplan-Meier estimates.

RESULTS

Of the 7121 patients in the cohort, 2616 met the primary endpoint (median time to event of 14.5 years) and 721 developed hepatopancreatobiliary malignancy. The most common malignancy was cholangiocarcinoma (n = 594); patients of advanced age at diagnosis had an increased incidence compared with younger patients (incidence rate: 1.2 per 100 patient-years for patients younger than 20 years old, 6.0 per 100 patient-years for patients 21-30 years old, 9.0 per 100 patient-years for patients 31-40 years old, 14.0 per 100 patient-years for patients 41-50 years old, 15.2 per 100 patient-years for patients 51-60 years old, and 21.0 per 100 patient-years for patients older than 60 years). Of all patients with PSC studied, 65.5% were men, 89.8% had classical or large-duct disease, and 70.0% developed IBD at some point. Assessing the development of IBD as a time-dependent covariate, Crohn's disease and no IBD (both vs ulcerative colitis) were associated with a lower risk of LTD (unadjusted hazard ratio [HR], 0.62; P < .001 and HR, 0.90; P = .03, respectively) and malignancy (HR, 0.68; P = .008 and HR, 0.77; P = .004, respectively). Small-duct PSC was associated with a lower risk of LTD or malignancy compared with classic PSC (HR, 0.30 and HR, 0.15, respectively; both P < .001). Female sex was also associated with a lower risk of LTD or malignancy (HR, 0.88; P = .002 and HR, 0.68; P < .001, respectively). In multivariable analyses assessing the primary endpoint, small-duct PSC characterized a low-risk phenotype in both sexes (adjusted HR for men, 0.23; P < .001 and adjusted HR for women, 0.48; P = .003). Conversely, patients with ulcerative colitis had an increased risk of liver disease progression compared with patients with Crohn's disease (HR, 1.56; P < .001) or no IBD (HR, 1.15; P = .002).

CONCLUSIONS

In an analysis of data from individual patients with PSC worldwide, we found significant variation in clinical course associated with age at diagnosis, sex, and ductal and IBD subtypes. The survival estimates provided might be used to estimate risk levels for patients with PSC and select patients for clinical trials.

Patients with large-duct primary sclerosing cholangitis and Crohn's disease have a better outcome than those with ulcerative colitis, or without IBD

BACKGROUND

Approximately 20% of primary sclerosing cholangitis (PSC) patients with concomitant inflammatory bowel disease (IBD) have Crohn's disease (CD).

AIM

To compare PSC/CD with other PSC patients.

METHODS

Retrospective study of 240 PSC patients diagnosed between 1975 and 2012 (median follow-up 12 years). Activity of PSC at diagnosis was assessed by liver biopsy, Mayo risk and ERC scores. Survival without liver transplantation, number of transplantations and liver-related death were endpoints.

RESULTS

Sixty-three per cent of patients had IBD: 105 UC, 32 CD and 14 IBD unclassified (IBDu). IBD was diagnosed before PSC in 50%. The yearly development of PSC after diagnosing IBD was similar in UC, CD or IBDu. Small-duct PSC was present in 28% of PSC/CD compared to 3% of PSC/UC. Small-duct PSC had a markedly better survival than large-duct PSC: no patient developed cholangiocarcinoma or liver-related death, but colorectal cancer occurred in three patients. In large-duct PSC, a more favourable outcome was evident in patients with CD. The liver disease was less progressive: one patient underwent liver transplantation compared to 28% and liver-related deaths were absent compared to 7% in the other PSC groups.

CONCLUSIONS

The prevalence of PSC with concomitant Crohn's disease is relatively rare, but the outcome is more benign than PSC with UC or without IBD. Approximately one-fourth has small-duct PSC. In large-duct PSC/CD, liver disease is less aggressive and the outcome is much better. The outcome of PSC patients with UC resembled that of PSC without IBD.

Primary sclerosing cholangitis, Crohn's disease and HLA-B27 in black South African women

Crohn's disease is rare in South African black people and primary sclerosing cholangitis (PSC) is also rare in black patients with IBD, from South Africa. The presence of HLA-B27 is generally associated with seronegative spondylo-arthropathies and correlates with the occurrence of ankylosing spondylitis, recurrent mouth ulcers and uveitis, in patients with IBD. We describe two women with the combination of Crohn's disease, PSC and HLA-B27 from our cohort of the last 5 years of three black patients with Crohn's disease. Crohn's disease, PSC and HLA-B27 respectively, occur rarely in black South Africans and their concurrent presence in two black women suggests a pathogenetic link of HLA-B27 between Crohn's disease and PSC in this population. Female gender might be an additional determinant in this setting.

Malignancies and mortality in 200 patients with primary sclerosering cholangitis: a long-term single-centre study

BACKGROUND

The outcome of primary sclerosing cholangitis (PSC) has improved by liver transplantation (LT), but patients often develop malignancies. We analysed morbidity and mortality patterns to define strategies to prevent complications.

METHODS

Two hundred consecutive patients diagnosed before October 2005 were studied.

RESULTS

Malignancies developed in 40 (20%) and led to death in 28 patients (45.9% of the 61 mortalities). Cholangiocarcinoma (CCa) developed in 13 patients, and was detected shortly after the diagnosis of PSC in 31%. Colorectal carcinomas were documented in 10 and dysplastic adenomas in four patients; eight had ulcerative colitis, two Crohn's colitis, one unclassified inflammatory bowel disease (IBDu), three had no IBD. Five died of colorectal cancer. Three carcinomas and two adenomas were localized in the caecum or ascending colon, but most (n=10) in the recto-sigmoidal region. Hepatocellular carcinoma developed in three patients with advanced fibrosis/cirrhosis, and pancreatic cancer in five. LT has been carried out in 42 patients, 6.1 years (median, 0.5-25) after the diagnosis of PSC. Mortality was due to hepatic complications in 13 patients. Within 5 years of the diagnosis, deaths were because of malignancy in 12 patients and to hepatobiliary decompensation in only three, whereas 18 had been transplanted.

CONCLUSIONS

Since the use of transplantation, malignancies are the major cause of death. CCa has to be searched for in any new symptomatic patient. Colorectal malignancy occurs frequently. Colonoscopy at the diagnosis of PSC is obligatory and should be repeated at 1-2 years interval in the patients with IBD and every 5 years in those without IBD.

Culture of mouse embryonic stem cells with serum but without exogenous growth factors is sufficient to generate functional hepatocyte-like cells

Mouse embryonic stem cells (mESC) have been used to study lineage specification in vitro, including towards a hepatocyte-like fate, and such investigations guided lineage differentiation protocols for human (h)ESC. We recently described a four-step protocol to induce hepatocyte-like cells from hESC which also induced hepatocyte-like cell differentiation of mouse induced pluripotent stem cells. As ESC also spontaneously generate hepatocyte-like cells, we here tested whether the growth factors and serum used in this protocol are required to commit mESC and hESC to hepatocyte-like cells. Culture of mESC from two different mouse strains in the absence of serum and growth factors did not induce primitive streak/definitive endoderm genes but induced default differentiation to neuroectoderm on day 6. Although Activin-A and Wnt3 induced primitive streak/definitive endoderm transcripts most robustly in mESC, simple addition of serum also induced these transcripts. Expression of hepatoblast genes occurred earlier when growth factors were used for mESC differentiation. However, further maturation towards functional hepatocyte-like cells was similar in mESC progeny from cultures with serum, irrespective of the addition of growth factors, and irrespective of the mouse strain. This is in contrast to hESC, where growth factors are required for specification towards functional hepatocyte-like cells. Culture of mESC with serum but without growth factors did not induce preferential differentiation towards primitive endoderm or neuroectoderm. Thus, although induction of primitive streak/definitive endoderm specific genes and proteins is more robust when mESC are exposed to a combination of serum and exogenous growth factors, ultimate generation of hepatocyte-like cells from mESC occurs equally well in the presence or absence of exogenous growth factors. The latter is in contrast to what we observed for hESC. These results suggest that differences exist between lineage specific differentiation potential of mESC and hESC, requiring optimization of different protocols for ESC from either species.

Human embryonic and rat adult stem cells with primitive endoderm-like phenotype can be fated to definitive endoderm, and finally hepatocyte-like cells

Stem cell-derived hepatocytes may be an alternative cell source to treat liver diseases or to be used for pharmacological purposes. We developed a protocol that mimics mammalian liver development, to differentiate cells with pluripotent characteristics to hepatocyte-like cells. The protocol supports the stepwise differentiation of human embryonic stem cells (ESC) to cells with characteristics of primitive streak (PS)/mesendoderm (ME)/definitive endoderm (DE), hepatoblasts, and finally cells with phenotypic and functional characteristics of hepatocytes. Remarkably, the same protocol can also differentiate rat multipotent adult progenitor cells (rMAPCs) to hepatocyte-like cells, even though rMAPC are isolated clonally from cultured rat bone marrow (BM) and have characteristics of primitive endoderm cells. A fraction of rMAPCs can be fated to cells expressing genes consistent with a PS/ME/DE phenotype, preceding the acquisition of phenotypic and functional characteristics of hepatocytes. Although the hepatocyte-like progeny derived from both cell types is mixed, between 10-20% of cells are developmentally consistent with late fetal hepatocytes that have attained synthetic, storage and detoxifying functions near those of adult hepatocytes. This differentiation protocol will be useful for generating hepatocyte-like cells from rodent and human stem cells, and to gain insight into the early stages of liver development.

Quantitation of replication of the HCV genome in human livers with end-stage cirrhosis by strand-specific real-time RT-PCR assays: methods and clinical relevance

HCV replicates in liver via an intermediate negative strand RNA. To study the relevance of HCV genome replication, quantitative strand-specific HCV real-time RT-PCR assays were developed and applied to livers explanted because of end-stage cirrhosis. The assays have broad ranges of determination and a high reproducibility and accuracy. Analysis of five different samples showed an even distribution of HCV genomes in four livers. Hepatic concentrations of positive (PS)- and negative (NS)-strand RNA did correlate with each other, with PS/NS ratios ranging between 3 and 340. Hepatic concentrations of HCV-PS or -NS RNA did not correlate with serum HCV-RNA levels or with genotypes. A high HCV envelope-2 protein expression correlated with a low NS concentration. HCV-PS and -NS levels, E2 protein expression and genotype did not correlate with biochemical tests or with histological changes in the explanted liver, but the ratio NS/PS, a marker of viral replication, correlated with the severity of the recurrent post-transplant hepatitis caused by HCV. This suggests the existence of an extra-hepatic location of HCV with comparable viral replication rate being responsible for the infection of the newly transplanted liver.

Cystic fibrosis transmembrane conductance regulator gene polymorphisms in patients with primary sclerosing cholangitis

BACKGROUND/AIMS

Primary sclerosing cholangitis (PSC) is a progressive cholestatic disease commonly associated with inflammatory bowel disease (IBD) and characterized by fibrosing inflammatory destruction of bile ducts. The histological features in the liver of PSC patients are similar to those observed in cystic fibrosis (CF). Our aim was to study whether variants in the CFTR gene are associated with the occurrence and/or evolution of PSC.

METHODS

PSC patients (n=140) were genotyped for F508del, the TGmTn variants, and four additional polymorphic loci (1001+11 C>T, M470V, T854T and Q1463Q), and compared to 136 matched healthy controls.

RESULTS

The 1540G-allele, encoding V470, was less frequent in PSC (52%) than in controls (64%, p=0.003), and was associated with protection against PSC in individuals without IBD (OR 0.25, 95% CI 0.12-0.52, p=0.0002). Also TG11-T7 was less frequent in PSC (53%) than in controls (61%, p=0.04), this haplotype was associated with reduced risk for PSC (OR 0.34, 95% CI 0.17-0.70, p=0.003) in individuals without IBD.

CONCLUSIONS

In this cohort of PSC patients, several CFTR-variants affecting the functional properties of the CFTR protein seem to offer protection against the development of PSC, confirming our hypothesis that CFTR might be implicated in the pathogenesis of PSC.

Congenital veno-venous malformations of the liver: widely variable clinical presentations

BACKGROUND AND AIM

Congenital portosystemic veno-venous malformations are rare abnomalities that often remain undiagnosed. Typically they are classified by their anatomical characteristics according to Morgan (extrahepatic, Abernethy malformations type Ia,b and II) and Park (intrahepatic, types 1-4). However, their clinical presentation is less dependent on the anatomical type.

METHOD

We reviewed the clinical characteristics of six cases drawn from our files (from 1970 to 2006).

RESULTS

One patient, a 25-year-old male, had extrahepatic shunting whereby the liver receives only arterial blood because the portal vein (PV) connects with the inferior caval vein (ICV) (Abernethy Ib); he presented with episodes of jaundice and pruritus. Three patients had extrahepatic shunting with patent intrahepatic portal veins, but with shunting of splenomesenterial blood towards the ICV (Abernethy II); these included a 66-year-old male with hepatic encephalopathy, a 17-year-old female with (porto?-)pulmonary hypertension without portal hypertension, and a 33-year-old female with epidsodes of acute pain secondary to spontaneous bleeding within a primary liver tumor. Two patients had intrahepatic shunting; these included an 8-year-old boy who was diagnosed incidentally during work-up for abnormal liver enzymes with a communication between right PV and ICV (Park type 1), and a 59-year-old male with multiple PV-ICV-shunts in several liver segments (Park, type 4) who presented with hepatic encephalopathy.

CONCLUSION

Patients often present with signs of hepatic shunting (encephalopathy, pulmonary hypertension, hepatopulmonary syndrome, and/or hypoglycemia) with relative sparing of the synthetic liver function in the absence of portal hypertension. Some shunts present with space-occupying lesions (focal nodular hyperplasia, hepatocellular carcinoma, nodular regenerative hyperplasia, etc.) or biliary atresia. Finally, some cases are detected incidentally.

Bilirubin in clinical practice: a review

Bilirubin is an endogenous compound that can be toxic under certain conditions but, on the other hand, mild unconjugated hyperbilirubinaemia might protect against cardiovascular diseases and tumour development. Serum bilirubin levels are often enhanced under a variety of clinical conditions. These are discussed and the mechanisms are outlined.

Porphyria cutanea tarda and liver disease. A retrospective analysis of 17 cases from a single centre and review of the literature

BACKGROUND/AIMS

Sporadic Porphyria Cutanea Tarda (sPCT) is associated with liver disease, e.g. HCV infection, haemochromatosis and especially alcoholic liver disease. We conducted a retrospective analysis on the prevalence of liver disorders in association with Porphyria Cutanea Tarda (PCT), in a university referral centre.

METHODS

The PCT cases were retrieved from computerized databases. Patient files lacking information on the presence of concomitant liver disease were excluded from further analysis.

RESULTS

29 PCT patients were retrieved from our databases, of which 17 patients with sPCT were retained for further analysis. Patients were middle aged (mean age: 43 +/- 3) and there was no gender difference (10 males vs. 7 females). Almost all patients had iron overload (14/17). 5 patients had chronic HCV, with type 1b in 3 of them, 7 abused alcohol, 4 patients had hereditary haemochromatosis (3 homozygous C282Y--1 heterozygous H63D/C282Y). In 3 patients sPCT was associated with medication intake and one patient had chronic hepatitis B (HBV). 13 patients were treated with phlebotomies, with success in 11/13. 4 patients were treated with chloroquine, 3 of which also underwent phlebotomies. Of the 5 patients with HCV, 3 were successfully treated with combined antiviral therapy; one of them is planned to be treated; one patient never received therapy and was lost from follow-up. One patient developed hepatocellular carcinoma (HCC) during a median follow-up of 24 years.

CONCLUSIONS

We found a significant association between sPCT and liver disorders, such as chronic HCV infection, alcohol abuse, iron overload and hereditary haemochromatosis. Therefore, patients presenting with PCT should be screened for concomitant liver disease. Iron overload is present in a majority of patients, the majority of patients can be successfully treated with phlebotomies. The risk of developing HCC in our sPCT patients and in literature is low.

Incidence, diagnosis, and therapy of cholangiocarcinoma in patients with primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) can lead to the development of cholangiocarcinoma (CCA). The tumor may present as an intrahepatic focal cholangiocellular carcinoma but more often as a ductal infiltrating desmoplastic lesion. CCA is found synchronously with the diagnosis of PSC in 20-30% and within 1 year in 50%. During later follow-up, the yearly developmental rate of CCA is 0.5-1.5%. Most patients with PSC and CCA do not yet have cirrhosis but present with a severe stenosis at the hilum of the liver. This type of tumor is difficult to diagnose by imaging techniques.(18)F-FDG-PET scanning and CEA or CA 19-9 are not early diagnostic tools. Regular MRI, multislice CT, and repeated endoscopically obtained brush cytology of stenotic lesions are recommended. The recent use of more extensive surgical resection techniques in patients with CCA results in 5-year survival rates of > or =50%. If tumors are small or incidental findings, liver transplantation leads to a 3- to 5-year survival rate of 35%. Pretransplant radiotherapy with 5-FU chemosensitization followed by endoscopic brachytherapy with iridium-192 seems to greatly improve the outcome of transplantation. Treatment with ursodeoxycholic acid may prevent development of CCA.

Statins in hepatobiliary diseases: effects, indications and risks

BACKGROUND AND STUDY AIMS

Statins are among the most frequently used medications. Our aim was to study their indications or contraindications in hepatobiliary diseases.

PATIENT AND METHODS

This study was stimulated by a patient with PBC, marked hypercholesterolemia and cardiac problems.

RESULTS

Besides a lipid lowering effect, statins have other benefits, such as prevention of arterosclerosis, reduction of the risk of developing diabetes and inhibition of fibrogenesis. The effects depend on the type of statin, the genetic and acquired characteristics of the patient and the interaction with other medications. Side effects such as myopathy and liver toxicity are rather rare but should be monitored. The use of statins in liver disease is not clearly defined. Hyperlipidaemia is a risk factor for arteriosclerosis in NAFLD (Non Alcoholic Fatty Liver Disease), but fibrates might constitute the treatment of choice. Preliminary data suggest that biochemical and histological improvement in NAFLD might be obtained with atorvastatin or pravastatin. The use of statins in the medical therapy of gallstones remains unclear. Combination with ursodeoxycholic acid therapy might have a beneficial effect in cases of stones with mixed composition. Patients with Primary Biliary Cirrhosis or with chronic cholestasis in general have high HDL-cholesterol levels but a large amount of Lipoprotein X particles, which have a protective effect. As such, statin therapy is often not really indicated.

CONCLUSION

When cardiovascular problems arise in patients with chronic cholestasis, an underlying factor should be looked for. The lipid abnormalities depend also on the stage of the PBC.

HBx or HCV core gene expression in HepG2 human liver cells results in a survival benefit against oxidative stress with possible implications for HCC development

Hepatitis virus replication in the liver is often accompanied by inflammation resulting in the formation of reactive oxygen species (ROS) and nitric oxide (NO) and these may induce cell death. We investigated whether the expression of HBx or HCV core protein in HepG2 cells has an influence on the sensitivity of these cells for oxidative radicals. Our previous study, using the inducible HBV model of HepAD38, revealed that oxidative-stress-related genes are upregulated by virus replication. In the present study, we examined the intracellular pro-oxidant status with dichlorofluorescein (DCF) in HepG2 cell lines transfected with HBx, HbsAg and HCV core. Baseline intracellular oxidative levels were not different in the cell lines expressing viral proteins as compared to control. However, when these cells were exposed to H(2)O(2), the viral protein expressing cells, especially those expressing HBx, showed a reduced level of ROS. This suggests that HBx and HCV core transfected cells can convert H(2)O(2) to less reactive compounds at a higher rate than the control cells. When HBx or HCV core expressing cells were exposed to peroxynitrite (a highly reactive product formed under physiological conditions through interaction of superoxide (O(2)(-)) with NO) these cells were less sensitive to induction of cell death. In addition, these cell lines were less prone to cell death when exposed to H(2)O(2) directly. In conclusion, HBx and HCV core expression in HepG2 cells leads to a survival benefit under oxidative stress which in vivo can be induced during inflammation.

MELD score to predict outcome in adult patients with non-acetaminophen-induced acute liver failure

AIMS/BACKGROUND

A model for end stage liver disease (MELD) score >30 was proposed as an excellent predictor of mortality in patients with non-acetaminophen-induced acute liver failure (ALF). We analyzed the prognostic value of MELD score in our patients with ALF who were prospectively registered in our database since 1990.

METHODS

Overall, 106 patients met the criteria of ALF. Excluding seven patients with acetaminophen etiology, 99 patients (42+/-15 years, 40M/59F) were studied.

RESULTS

Causes were cryptogenic (n=38), viral (n=29), drugs (n=20) and miscellaneous (n=12). Of these, 37% (n=37) survived with medical management alone (group I), 16% (n=16) died (group II) and 46% (n=46) underwent liver transplantation (group III). The strongest predictors of poor outcome were advanced encephalopathy, cryptogenic/drug-induced/hepatitis B etiology and a high MELD score. At the time of diagnosis, King's College Hospital criteria and MELD score >30 had similar high negative predictive value (92% and 91%, respectively) and low positive predictive value (52% and 56%, respectively). The predictive values improved only slightly during follow-up. The best cut-off point for MELD score to discriminate between survivors and nonsurvivors was >35, with a sensitivity and specificity of 86% and 75%, respectively.

CONCLUSIONS

MELD score, which mostly takes into consideration the degree of liver impairment, has a similar prognostic value as King's College Hospital criteria to predict outcome in adult patients with nonacetaminophen-induced ALF. Overall, all current scores miss accuracy and therefore there is a clear need for factors that can better predict the regeneration of the liver in this setting.

Hepatitis C and insulin resistance: mutual interactions. A review

Worldwide approximately 200 million people are chronically infected with hepatitis C virus (HCV). Chronic HCV infection represents the leading cause of liver cirrhosis and the main indication for liver transplantation in the western world. In addition, chronic HCV infection is associated with numerous clinical manifestations, including type 2 diabetes. An obvious and frequently suggested explanation for the connection between HCV infection and type 2 diabetes is that cirrhosis by itself causes insulin resistance. However, the prevalence of type 2 diabetes in HCV cirrhosis is higher than in HBV cirrhosis (23.6% vs 9.4%). This suggests that HCV infection by itself can lead to insulin resistance and predispose to the onset of type 2 diabetes. First, HCV core protein induces hepatic steatosis by inhibition of microsomal triglyceride transfer protein and hepatic steatosis causes insulin resistance. Secondly, HCV core protein inhibits, through elevation of TNF-alfa and other factors, the insulin-signalling pathways causing insulin resistance. Moreover, recent data strongly suggest that insulin resistance is an important predictor of poor response to antiviral therapy in chronic hepatitis patients treated with peginterferon plus ribavirin.

Both Ca2+ -dependent and -independent pathways are involved in rat hepatic stellate cell contraction and intrahepatic hyperresponsiveness to methoxamine

In chronic liver injury, hepatic stellate cells (HSCs) have been implicated as regulators of sinusoidal vascular tone. We studied the relative role of Ca(2+)-dependent and Ca(2+)-independent contraction pathways in rat HSCs and correlated these findings to in situ perfused cirrhotic rat livers. Contraction of primary rat HSCs was studied by a stress-relaxed collagen lattice model. Dose-response curves to the Ca(2+) ionophore A-23187 and to the calmodulin/myosin light chain kinase inhibitor W-7 served to study Ca(2+)-dependent pathways. Y-27632, staurosporin, and calyculin (inhibitors of Rho kinase, protein kinase C, and myosin light chain phosphatase, respectively) were used to investigate Ca(2+)-independent pathways. The actomyosin interaction, the common end target, was inhibited by 2,3-butanedione monoxime. Additionally, the effects of W-7, Y-27632, and staurosporin on intrahepatic vascular resistance were evaluated by in situ perfusion of normal and thioacetamide-treated cirrhotic rat livers stimulated with methoxamine (n = 25 each). In vitro, HSC contraction was shown to be actomyosin based with a regulating role for both Ca(2+)-dependent and -independent pathways. Although the former seem important, an important auxiliary role for the latter was illustrated through their involvement in the phenomenon of "Ca(2+) sensitization." In vivo, preincubation of cirrhotic livers with Y-27632 (10(-4) M) and staurosporin (25 nM), more than with W-7 (10(-4) M), significantly reduced the hyperresponsiveness to methoxamine (10(-4) M) by -66.8 +/- 1.3%, -52.4 +/- 2.7%, and -28.7 +/- 2.8%, respectively, whereas in normal livers this was significantly less: -43.1 +/- 4.2%, -40.2 +/- 4.2%, and -3.8 +/- 6.3%, respectively. Taken together, these results suggest that HSC contraction is based on both Ca(2+)-dependent and -independent pathways, which were shown to be upregulated in the perfused cirrhotic liver, with a predominance of Ca(2+)-independent pathways.

Primary graft nonfunction and Kupffer cell activation after liver transplantation from non-heart-beating donors in pigs

More extensive use of non-heart-beating donors (NHBD) could reduce mortality on liver transplantation waiting lists, but this is associated with more primary nonfunction (PNF). We assessed which parameters are involved in the development of PNF in livers from NHBD in a previously validated pig liver transplantation model, in which livers were transplanted after exposure to incremental periods of warm ischemia. The risk of PNF was unacceptably high (>50%) when livers were exposed to >30 minutes' warm ischemia before a short cold ischemic period. This study examined how PNF is affected by Kupffer cell activation (beta-galactosidase), the generation of cytokines tumor necrosis factor alpha and interleukin 6, antioxidant mechanisms (ascorbic acid, alpha-tocopherol, reduced glutathione), circulating redox-active iron, and sinusoidal endothelial cell function (hyaluronic acid clearance). Kupffer cells were more activated in PNF recipients, as suggested by higher beta-galactosidase levels (15 minutes after reperfusion), and secondarily, by higher production of tumor necrosis factor alpha and interleukin 6 (180 minutes after reperfusion). In addition, alpha-tocopherol and reduced glutathione were lower, and ascorbic acid and redox-active iron higher in PNF recipients. Finally, PNF grafts displayed progressively decreasing hyaluronic acid clearance (suggesting sinusoidal endothelial cell dysfunction) and parenchymal edema. Consequently, a reduced-flow phenomenon was documented. In grafts from NHBD that are destined to fail, beta-galactosidase activity (a surrogate of Kupffer cell activation) is higher, proinflammatory cytokines are overproduced, some antioxidant mechanisms fail, and circulating redox-active iron is more rapidly released. A no-flow phenomenon is eventually observed in these failing grafts.

Nitroflurbiprofen, a nitric oxide-releasing cyclooxygenase inhibitor, improves cirrhotic portal hypertension in rats

BACKGROUND & AIMS

We studied whether administration of nitroflurbiprofen (HCT-1026), a cyclooxygenase inhibitor with nitric oxide (NO)-donating properties, modulates the increased intrahepatic vascular tone in portal hypertensive cirrhotic rats.

METHODS

In vivo hemodynamic measurements (n = 8/condition) and evaluation of the increased intrahepatic resistance by in situ perfusion (n = 5/condition) were performed in rats with thioacetamide-induced cirrhosis that received either nitroflurbiprofen (45 mg/kg), flurbiprofen (30 mg/kg, equimolar concentration to nitroflurbiprofen), or vehicle by intraperitoneal injection 24 hours and 1 hour prior to the measurements. Additionally, we evaluated the effect of acute administration of both drugs (250 micromol/L) on the intrahepatic vascular tone in the in situ perfused cirrhotic rat liver (endothelial dysfunction and hyperresponsiveness to methoxamine) and on hepatic stellate cell contraction in vitro. Typical systemic adverse effects of nonsteroidal anti-inflammatory drugs, such as gastrointestinal ulceration, renal insufficiency, and hepatotoxicity, were actively explored.

RESULTS

In vivo, nitroflurbiprofen and flurbiprofen equally decreased portal pressure (8 +/- 0.8 and 8.4 +/- 0.1 mm Hg, respectively, vs 11.8 +/- 0.6 mm Hg) and reduced the total intrahepatic vascular resistance. Systemic hypotension was not aggravated in the different treatment groups (P = .291). In the perfused cirrhotic liver, both drugs improved endothelial dysfunction and hyperresponsiveness. This was associated with a decreased hepatic thromboxane A(2)-production and an increased intrahepatic nitrate/nitrite level. In vitro, nitroflurbiprofen, more than flurbiprofen, decreased hepatic stellate cells contraction. Flurbiprofen-treated rats showed severe gastrointestinal ulcerations (bleeding in 3/8 rats) and nefrotoxicity, which was not observed in nitroflurbiprofen-treated cirrhotic rats.

CONCLUSIONS

Treatment with nitroflurbiprofen, an NO-releasing cyclooxygenase inhibitor, improves portal hypertension without major adverse effects in thioacetamide-induced cirrhotic rats by attenuating intrahepatic vascular resistance, endothelial dysfunction, and hepatic hyperreactivity to vasoconstrictors.

Orlistat treatment is safe in overweight and obese liver transplant recipients: a prospective, open label trial

Obesity is a frequent complication following liver transplantation and is insufficiently responsive to dietary and life style advice. We studied the safety of orlistat treatment in obese and overweight liver transplant recipients (n = 15) on a stable tacrolimus-based immunosuppressive regimen. For safety reasons, the treatment period was restricted (6 months 120 mg t.i.d., 3 months 120 mg daily). Three patients dropped out, tacrolimus dose was adjusted in six of 12 remaining patients (dose reduction in 4, increase in 2, P = N.S.). All dose adjustments occurred during the 6 months of orlistat 120 mg t.i.d. therapy. No drug intolerance, adverse events or episodes of rejection occurred during the study. Efficacy of orlistat treatment in this population could not be shown, because a formal control population was not included in this safety trial. Moreover, only a significant decrease of waist circumference (P < 0.01 versus start of the study), but not of weight or body mass index, was achieved in the treated group. Orlistat treatment is well tolerated in liver transplant recipients and can be started safely, provided immunosuppressive drug levels and dietary adherence are closely monitored.

Viral interaction and clinical implications of coinfection of hepatitis C virus with other hepatitis viruses

Coinfection with other hepatitis viruses modifies the viral profile in serum and leads to more liver damage and more rapid progression during the course of hepatitis C virus infection. The viral interference is not only carried out by virus-virus or by virus-cell interactions but also by an enhanced immune response. A superinfecting viral infection does not crossactivate protective immune responses to the pre-existing virus albeit the latter can become undetectable. The induced cytokine stimulation might enhance the hepatic inflammation. Moreover, hepatitis B virus coinfection increases the risk of development of hepatocellular carcinoma in hepatitis C virus patients through common necro-inflammatory pathways or by direct oncogenic activity of hepatitis B virus. Viral interaction also complicates the management of the coinfection because hepatitis C virus impairs the humoral response to hepatitis A virus and hepatitis B virus vaccines, and because pharmacological suppression of hepatitis C virus endangers dually infected patients with reactivation of coinfected hepatitis B virus. Optimized strategies and follow-up are thus necessary in the treatment of infection with multiple viruses. It seems thus necessary to look for markers of hepatitis B virus and/or hepatitis D virus infection in chronic hepatitis patients positive for hepatitis C virus antibodies but negative for hepatitis C virus RNA, and equally well to search for hepatitis C virus RNA in HBsAg-negative/anti-HBc-positive patients with a low level of serum hepatitis B virus DNA.

Effect of the molecular adsorbent recirculating system and Prometheus devices on systemic haemodynamics and vasoactive agents in patients with acute-on-chronic alcoholic liver failure

Introduction

Patients with acute-on-chronic liver failure show an aggravated hyperdynamic circulation. We evaluated, in a controlled manner, potential changes in systemic haemodynamics induced by the molecular adsorbent recirculating system (MARS) and the Prometheus system liver detoxification devices in a group of patients with acute-on-chronic liver failure.

Methods

Eighteen patients (51.2 ± 2.3 years old; Child–Pugh score, 12.5 ± 0.2; Maddrey score, 63.1 ± 5.0; hepatic venous pressure gradient, 17.6 ± 0.9 mmHg) with biopsy-proven alcoholic cirrhosis and superimposed alcoholic hepatitis were either treated with standard medical therapy (SMT) combined with MARS (n = 6) or Prometheus (n = 6) or were treated with SMT alone (n = 6) on three consecutive days (6 hours/session). Liver tests, systemic haemodynamics and vasoactive substances were determined before and after each session.

Results

Groups were comparable for baseline haemodynamics and levels of vasoactive substances. Both MARS and Prometheus decreased serum bilirubin levels (P < 0.005 versus SMT), the Prometheus device being more effective than MARS (P = 0.002). Only MARS showed significant improvement in the mean arterial pressure (Δchange, +9 ± 2.4 mmHg versus -0.3 ± 2.4 mmHg with Prometheus and -5.2 ± 2.1 mmHg with SMT, P < 0.05) and in the systemic vascular resistance index (Δchange, +131.5 ± 46.2 dyne.s/cm⁵/m² versus -92.8 ± 85.2 dyne.s/cm⁵/m²with Prometheus and -30.7 ± 32.5 dyne.s/cm⁵/m² with SMT; P < 0.05), while the cardiac index and central filling remained constant. This circulatory improvement in the MARS group was paralleled by a decrease in plasma renin activity (P < 0.05), aldosterone (P < 0.03), norepinephrine (P < 0.05), vasopressin (P = 0.005) and nitrate/nitrite levels (P < 0.02).

Conclusion

The MARS device, and not the Prometheus device, significantly attenuates the hyperdynamic circulation in acute-on-chronic liver failure, presumably by a difference in removal rate of certain vasoactive substances. These findings suggest conspicuous conceptual differences among the albumin dialysis devices.

The clinicopathological and prognostic relevance of cytokeratin 7 and 19 expression in hepatocellular carcinoma. A possible progenitor cell origin

AIMS

Cytokeratin (CK) 7 and CK19 expression, present in hepatic progenitor cells (HPCs) and in cholangiocytes but not in normal hepatocytes, has been reported in some hepatocellular carcinomas (HCCs); however, the incidence and relevance of this expression in HCC in Caucasians is not known. Therefore, our aim was to study the occurrence and clinicopathological characteristics of HCC expressing CK7 and/or CK19 in 109 Caucasian patients.

METHODS AND RESULTS

The expression of hepatocellular differentiation markers (Hepar, canalicular polyclonal carcinoembryonic antigen), biliary/progenitor cell markers (CK7, CK19), alpha-fetoprotein (AFP), p53 and beta-catenin in HCC was semiquantitatively assessed by immunohistochemistry. Of 109 HCCs, 78 were CK7-/CK19- (72%), 13 CK7+/CK19- (12%), seven CK7-/CK19+ (6%), 11 CK7+/CK19+ (10%). CK19 expression was significantly associated with elevated serum AFP (400 ng/ml) (P = 0.023), tumour AFP expression (P < 0.0001), presence in serum of anti-hepatitis B core (P = 0.016), less fibrosis in non-neoplastic parenchyma (P = 0.009) and less nuclear beta-catenin expression (P = 0.021). CK7 expression was significantly associated with elevated serum bilirubin (> 2 mg/dl) (P = 0.0005) and less nuclear beta-catenin expression (P = 0.003). HCC expressing CK19 had a higher rate of recurrence (P = 0.009, hazard ratio 12.5, n = 31) after liver transplantation compared with CK19- tumours.

CONCLUSIONS

In our series, 28% of HCCs contained cells expressing CK7 and/or CK19. They potentially derive from HPCs. The higher recurrence rate of CK19+ HCC after transplantation suggests a worse prognosis for these HCCs compared with CK19- HCC.

Hepatitis B virus replication causes oxidative stress in HepAD38 liver cells

We used human hepatoma HepAD38 cells, in which HBV production is under the control of a tetracycline-regulated promotor, to investigate changes induced in the host cell by HBV replication that could contribute to malignant transformation. Parameters of oxidative stress (malondialdehyde, glutathione) and cell proliferation were determined at different times after induction (0-96 h). In HBV-producing cells, the redox status peaked at 72 h. cDNA micro array analysis at 72 h post induction revealed 3 groups of genes that were up-regulated by HBV: (i) heat shock proteins, (ii) oxidative and metabolic stress and (iii) growth and apoptosis related genes. Continuous HBV production did not accelerate karyotypic changes in cells cultured for 4 months (18 passages).

IN CONCLUSION

HBV replication modulates host gene expression and induces oxidative stress. In this HepAD38 model early events (0-4 days) in the host cell after induction of HBV replication can be studied under strictly defined conditions.

Selection Criteria and Outcome of Patients Referred to Intestinal Transplantation: An European Center Experience

Until 1998, intestinal transplantation (SBT) had not been performed in our region of Flanders, Belgium. Potential SBT activity was not known and selection criteria had not been validated. A multidisciplinary SBT program was launched in 1998. We analyzed requests for SBT and outcomes in these patients whether with or without SBT. Listing for SBT was only considered for patients with irreversible short bowel syndrome who had developed life-threatening complications of total parenteral nutrition, but whose general condition was still thought compatible with surgery and immunosuppression. During the study period 1998 to 2004, one third of the requests for SBT (10/31) were deemed suitable. SBT in this group was lifesaving (100% survival) when performed in time. Mortality in this group without SBT was high (67%). Two thirds of the patients (21/31) did not fulfill the SBT inclusion criteria, either because they were "too moribund" to tolerate transplantation or because they were "too well". This preliminary study emphasized the importance of (1) early referral of potential SBT candidates, (2) adherence to strict criteria for listing patients for SBT, and (3) referral of intestinal donors to procurement organizations.

Breast cancer resistance protein (BCRP/ABCG2) is expressed by progenitor cells/reactive ductules and hepatocytes and its expression pattern is influenced by disease etiology and species type: possible functional consequences

Breast cancer resistance protein (BCRP/ABCG2) is an ATP-binding cassette transport protein that is expressed in several organs including the liver. Previous studies have shown that ABC transport proteins play an important pathophysiological role in several liver diseases. However, to date, expression pattern and possible role of BCRP in human liver diseases and animal models have not been studied in detail. Here we investigated the expression pattern of BCRP in normal liver, chronic parenchymal and biliary human liver diseases, and parallel in different rat models of liver diseases. Expression was studied by immunohistochemistry and additionally by RT-PCR analysis in Thy-1-positive rat oval cells. Bile ducts, hepatic progenitor cells, reactive bile ductules, and blood vessel endothelium were immunoreactive for BCRP in normal liver and all types of human liver diseases and in rat models. BCRP was expressed by the canalicular membrane of hepatocytes in normal and diseased human liver, but never in rat liver. Remarkably, there was also expression of BCRP at the basolateral pole of human hepatocytes, and this was most pronounced in chronic biliary diseases. In conclusion, BCRP positivity in the progenitor cells/reactive ductules could contribute to the resistance of these cells to cytotoxic agents and xenotoxins. Basolateral hepatocytic expression in chronic biliary diseases may be an adaptive mechanism to pump bile constituents back into the sinusoidal blood. Strong differences between human and rat liver must be taken into account in future studies with animal models.

Investigating the origin and spread of hepatitis C virus genotype 5a

Epidemiological and phylogenetic studies of hepatitis C virus (HCV) have identified six major HCV genotypes and have attempted to characterize their origin and spread worldwide. Putative regions of endemic infection have been identified for all HCV genotypes except HCV genotype 5a. Although HCV genotype 5a was previously thought to be largely restricted to the northern part of South Africa, this study reports an unexpected cluster of the genotype in West Flanders Province in Belgium. To investigate the molecular epidemiology of this cluster and of HCV genotype 5a in general, a rigorous phylogenetic analysis of Belgian and South African HCV genotype 5a samples was performed. Remarkably, the Belgian and South African strains form two distinct clusters of similar diversity. We used a Bayesian coalescent method to estimate the rate of virus spread through time for HCV genotype 5a in both regions. Our results indicate that HCV genotype 5a strains have been spreading independently in Belgium and South Africa for more than 100 years, with a rate of spread characteristic of an epidemic genotype. These findings have major implications for tracing the origin of HCV genotype 5a. Here, we speculate about the possible origins of these clusters.

A stable model of cirrhotic portal hypertension in the rat: thioacetamide revisited

BACKGROUND

Cirrhotic animal models are vital to investigate complications of chronic liver disease. We chronologically characterized the effect of thioacetamide, administrated orally and adapted weekly to weight changes, focusing on the optimal moment to obtain all typical features of portal hypertension and cirrhosis.

MATERIALS AND METHODS

Male Wistar rats, 200-250 g, were intoxicated for 6, 12 or 18 weeks (n = 8 per group), respectively, and compared with age-matched controls (n = 4 per group). An in-situ perfusion model was used to evaluate intrahepatic resistance and endothelial function. Splanchnic blood flow and portosystemic shunting were assessed by a perivascular flow probe.

RESULTS

Rats intoxicated for 6 or 12 weeks had no mortality and histologically showed hepatitis and advanced fibrosis, respectively. At 18 weeks, mortality was 16% (on a total of 56 animals) and only at that moment all animals showed homogenous macronodular cirrhosis with signs of high-grade hepatocellular dysplasia. Portal hypertension was present at 12 weeks (11 +/- 0.4 vs. 5.9 +/- 0.4 mmHg, P < 0.001), but was not associated with the hyperdynamic state until 18 weeks (12.1 +/- 0.8 vs. 5.6 +/- 0.5 mmHg, P < 0.001). At this latter time-point, we also observed increased intrahepatic resistance associated with endothelial dysfunction, hyperresponsiveness to vasoconstrictors, splanchnic hyperaemia and portosystemic shunting. These alterations were associated with increased systemic levels of nitrate/nitrite and thromboxane A(2).

CONCLUSION

Thioacetamide, adapted to weekly weight changes, leads to a homogenous, reproducible model of cirrhosis in the rat in 18 weeks, which is associated with all the typical characteristics of portal hypertension, including endothelial dysfunction.

CC-type chemokine receptor 5-Delta32 mutation protects against primary sclerosing cholangitis

BACKGROUND

Primary sclerosing cholangitis (PSC) is commonly associated with inflammatory bowel disease (IBD) and characterized by fibrosing inflammatory destruction of biliary ducts. The pathogenesis of PSC remains unknown, but immunological, bacterial, viral, and toxic factors play a role in a genetically susceptible host. We hypothesized that CC-type chemokine receptor 5 (CCR5) would be an interesting candidate gene for susceptibility to PSC from its chromosomal location within the IBD susceptibility locus on 3p21, as well as from a functional perspective. We therefore investigated the role of the functional 32-bp deletion in this gene (CCR5-Delta32) with regard to susceptibility to PSC.

METHODS

A total of 110 patients with PSC, 56 with concomitant IBD (23 with Crohn's disease, 28 with ulcerative colitis, 5 with indeterminate colitis), were collected. All of the subjects were genotyped for CCR5-Delta32 with polymerase chain reaction amplification, followed by detection on ethidium bromide-stained agarose gel. Genotypes and allele frequencies were compared with a cohort of IBD patients without PSC (n = 400) and healthy control subjects (n = 362).

RESULTS

The frequency of the CCR5-Delta32 mutation in PSC (6.8%) was significantly lower compared with IBD (12.6%; P = 0.016) and healthy control subjects (12.2%, P = 0.026), suggesting a protective effect of this mutation on PSC. None of the PSC patients with severe disease necessitating liver transplantation (n = 17) carried CCR5-Delta32.

CONCLUSIONS

Because an intact CCR5 receptor is needed for internalization of specific pathogens and homing of memory T lymphocytes to the liver, we hypothesize that a deficient expression of this receptor resulting from the CCR5-Delta32 variant may protect against PSC.

Review article: non-biological liver support in liver failure

Liver failure, whether acute or acute-on-chronic, remains an important cause of morbidity and mortality. The lack of liver detoxification, metabolic and regulatory functions of the liver leads to life-threatening complications, such as renal failure, altered immune response, hepatic coma and systemic haemodynamic dysfunction, eventually culminating in multiorgan failure. Current medical therapy involves the management of the precipitating event and treatment of complications until the liver eventually recovers, leaving us with no other treatment options than transplantation if these attempts fail. However, the shortage in cadaveric organs and other transplant-related problems, have prompted the need for alternative methods to provide liver support. As liver failure is often potentially reversible, considerable effort has been invested in the development of liver support systems. Currently, most of the experience is available for non-biological support systems. They represent the focus of this review, which aims to define the goals of liver support, to describe the design of the different existing devices and to analyse the available data to determine their current status in the management of patients with liver failure.

Portal hypertension: from pathophysiology to clinical practice

Portal hypertension (PHT) is responsible for the more severe and often lethal complications of cirrhosis such as bleeding oesophageal varices, ascites, renal dysfunction and hepatic encephalopathy. Because of the combined impact of these complications, PHT remains the most important cause of morbidity and mortality in patients with cirrhosis. Over the years, it has become clear that a decrease in portal pressure is not only protective against the risk of variceal (re)bleeding but is also associated with a lower long-term risk of developing complications and an improved long-term survival. A milestone in therapy was the introduction of non-selective beta-blockers for the prevention of bleeding and rebleeding of gastro-esophageal varices. However, in practice, less than half the patients under beta-blockade are protected from these risks, supporting the overall demand for innovation and expansion of our therapeutic armamentarium. Recent advances in the knowledge of the pathophysiology of cirrhotic PHT have directed future therapy towards the increased intrahepatic vascular resistance, which, in part, is determined by an increased hepatic vascular tone. This increased vasculogenic component provides the rationale for the potential use of therapies aimed at increasing intrahepatic vasorelaxing capacity via gene therapy, liver-selective nitric oxide donors and statines on the one hand, and at antagonizing excessive intrahepatic vasoconstrictor force through the use of endothelin antagonists, angiotensin blockers, alpha(1) adrenergic antagonists or combined alpha(1)- and non-selective beta-blockers or somatostatin analogues on the other. The focus of this review is to give an update on the pathophysiology of PHT in order to elucidate these potential novel strategies subsequently.

A role for asymmetric dimethylarginine in the pathophysiology of portal hypertension in rats with biliary cirrhosis

Reduced intrahepatic endothelial nitric oxide synthase (eNOS) activity contributes to the pathogenesis of portal hypertension (PHT) associated with cirrhosis. We evaluated whether asymmetric dimethylarginine (ADMA), a putative endogenous NOS inhibitor, may be involved in PHT associated with cirrhosis. Two rat models of cirrhosis (thioacetamide [TAA]-induced and bile duct excision [BDE]-induced, n = 10 each), one rat model of PHT without cirrhosis (partial portal vein-ligated [PPVL], n = 10), and sham-operated control rats (n = 10) were studied. We assessed hepatic NOS activity, eNOS protein expression, plasma ADMA levels, and intrahepatic endothelial function. To evaluate intrahepatic endothelial function, concentration-effect curves of acetylcholine were determined in situ in perfused normal rat livers and livers of rats with TAA- or BDE-induced cirrhosis (n = 10) that had been preincubated with either vehicle or ADMA; in addition, measurements of nitrite/nitrate (NOx) and ADMA were made in perfusates. Both models of cirrhosis exhibited decreased hepatic NOS activity. In rats with TAA-induced cirrhosis, this decrease was associated with reduced hepatic eNOS protein levels and immunoreactivity. Rats with BDE-induced cirrhosis had eNOS protein levels comparable to those in control rats but exhibited significantly higher plasma ADMA levels than those in all other groups. In normal perfused liver, ADMA induced impaired endothelium-dependent vasorelaxation and reduced NOx perfusate levels, phenomena that were mimicked by N(G)-nitro-L-arginine-methyl ester. In contrast to perfused livers with cirrhosis induced by TAA, impaired endothelial cell-mediated relaxation in perfused livers with cirrhosis induced by BDE was exacerbated by ADMA and was associated with a decreased rate of removal of ADMA (34.3% +/- 6.0% vs. 70.9% +/- 3.2%). In conclusion, in rats with TAA-induced cirrhosis, decreased eNOS enzyme levels seem to be responsible for impaired NOS activity; in rats with biliary cirrhosis, an endogenous NOS inhibitor, ADMA, may mediate decreased NOS activity.

Hereditary hyperferritinaemia-cataract syndrome: a challenging diagnosis for the hepatogastroenterologist

Hereditary hyperferritinaemia-cataract syndrome (HHCS) is a relatively rare disorder with an autosomal dominant trait. It can be caused by various mutations within the iron responsive element (IRE) of the L-ferritin gene. These mutations result in an increased translation of L-ferritin mRNA and consequently the accumulation of L-ferritin in different fluids and tissues. HHCS patients present with an isolated hyperferritinaemia in the absence of any sign of iron overload. Early onset bilateral cataract, probably due to accumulation of ferritin crystals in the lens, is the only presenting clinical manifestation. Internists, especially gastrohepatologists, should be aware of this syndrome and differentiate it from haemochromatosis which is much more frequent, in order to avoid unnecessary imaging procedures, liver biopsies and an eventual venesection therapy, which will only lead to microcytic anaemia. In the present paper we report the first cases with HHCS diagnosed in Belgium. At diagnosis, the seven known affected members of three different families had ferritin levels between 603 and 3432 microg/l (normal < 150 microg/l), and this in combination with normal iron and transferrin values. All of them were known with early-onset bilateral cataract and our postulated diagnosis of HHCS was confirmed after genetic sequencing of the L-ferritin gene, which showed a C39U point mutation in the first family, and an A40G point mutation in the IRE loop segment in the two other families. The other investigated members of the three families had normal ferritin values, no history of early-onset cataract and genetic analyses could not reveal a mutation in the IRE of their L-ferritin gene. In current clinical practice, gastroenterologists should remember that elevated ferritin levels in the absence of documented iron overload is not haemochromatosis.

Does ex vivo vascular resistance reflect viability of non-heart-beating donor livers?

AIMS

The use of non-heart-beating (NHB) donor livers is limited by a higher risk for primary nonfunction and the absence of methods to measure this risk. This study was designed to determine whether ex vivo vascular resistance of livers correlates with the length of warm ischemia (WI), and, thus, with viability of NHB livers.

METHODS

Porcine livers were recovered after 0, 45, or 90 minutes WI. Livers were flushed by gravity and cold stored for 3 hours. Thereafter, livers were perfused at 4 degrees C. Portal vein (PV) and hepatic artery (HA) vascular resistance were calculated during liver flush-out and during 24 hours of machine perfusion.

RESULTS

During flush-out, PV and HA vascular resistance were higher among livers with longer WI times; however, only in the PV did the results reach statistical significance. During machine perfusion, PV vascular resistance was low from the start and remained fairly constant. In contrast, HA vascular resistance was higher at the start but gradually diminished to reach a more constant value after 4-6 hours. No correlation was observed between HA or PV vascular resistance and WI during machine perfusion.

CONCLUSIONS

The vascular resistance during ex vivo machine perfusion of NHB livers does not correlate with the extent of WI damage and, therefore, cannot predict organ viability.

Liver fatty acid-binding protein: an early and sensitive plasma marker of hepatocellular damage and a reliable predictor of graft viability after liver transplantation from non-heart-beating donors

OBJECTIVE

Liver fatty acid-binding protein (L-FABP) is a small protein (15 kD) involved in the intracellular transport of long-chain fatty acids in the liver. The L-FABP is regarded as a sensitive marker for liver cell damage. In a pig model for liver transplantation (LTx) from non-heart-beating donors (NHBD), we evaluated plasma changes of L-FABP early after reperfusion of grafts exposed to increasing periods of warm ischemia (WI).

METHODS

Porcine livers were procured after 0, 15, 30, 45, and 60 minutes' WI. After 4 hours' cold ischemia (CI), LTx was performed. Primary graft nonfunction (PNF) and day 4 survival were recorded. Plasma samples were collected prior to and 15, 60, and 180 minutes after graft reperfusion for determination of L-FABP and aspartate transaminase (AST).

RESULTS

Early after reperfusion, levels of L-FABP correlated well with the duration of WI. The PNF developed in 100% of animals after 60 minutes of WI, 50% after 30, and 45 minutes' WI, and was absent after no WI and 15 minutes of WI. Day 4 survival was 100% in 0 minutes' WI, 83% in 15 minutes' WI, 50% in 30 and 45 minutes' WI, and 0% in 60 minutes of WI.

CONCLUSIONS

Plasma levels of L-FABP correlated well with WI and concomitant hepatocellular damage in LTx from NHBD. Monitoring of posttransplant L-FABP plasma levels is a valuable new tool to quantify early the extent of parenchymal cell damage of NHBD livers and to predict their viability and function.

Liver transplantation using livers from septuagenarian and octogenarian donors: an underused strategy to reduce mortality on the waiting list

Shortage of liver grafts is the only limiting factor for application of liver transplantation and causes an increasing mortality on the waiting list. Very old donors (>70 to 80 years old) are rarely referred to transplant centers because of the assumption that these livers will not work properly. Alternatively, transplant teams may be reluctant to use these very old livers due to the risk of poor posttransplant outcome. We reviewed our experience with seven liver transplantations using very old donor livers. We found that the results in terms of graft function and patient survival are adequate. Interestingly, the majority of these donors originated from a single referring donor unit (of more than 20 units who belong to our donor network) that systematically refers all brain-dead donors to the transplant center, independent of the age of the potential donor. This implies that many of these donors are left undetected in other units. In conclusion, very old donors should be referred to transplant centers since results of transplantation with these grafts are favorable.

Rapid protocol for electroporation of Clostridium perfringens

A rapid and simple method has been developed for the electroporation of Clostridium perfringens with plasmid DNA. The new improvements, harvesting cells early in the logarithmic stage of growth, keeping the cells at room temperature and the absence of post-shock incubation on ice increased transformation efficiency by one order of magnitude.