Clonal expansion of hepatocytes with a selective advantage occurs during all stages of chronic hepatitis B virus infection

Hepatocyte clone size was measured in liver samples of 21 patients in various stages of chronic hepatitis B virus (HBV) infection and from 21 to 76 years of age. Hepatocyte clones containing unique virus-cell DNA junctions formed by the integration of HBV DNA were detected using inverse nested PCR. The maximum hepatocyte clone size tended to increase with age, although there was considerable patient-to-patient variation in each age group. There was an upward trend in maximum clone size with increasing fibrosis, inflammatory activity and with seroconversion from HBV e-antigen (HBeAg)-positive to HBeAg-negative, but these differences did not reach statistical significance. Maximum hepatocyte clone size did not differ between patients with and without a coexisting hepatocellular carcinoma. Thus, large hepatocyte clones containing integrated HBV DNA were detected during all stages of chronic HBV infection. Using laser microdissection, no significant difference in clone size was observed between foci of HBV surface antigen (HBsAg)-positive and HBsAg-negative hepatocytes, suggesting that expression of HBsAg is not a significant factor in clonal expansion. Laser microdissection also revealed that hepatocytes with normal-appearing histology make up a major fraction of the cells undergoing clonal expansion. Thus, preneoplasia does not appear to be a factor in the clonal expansion detected in our assays. Computer simulations suggest that the large hepatocyte clones are not produced by random hepatocyte turnover but have an as-yet-unknown selective advantage that drives increased clonal expansion in the HBV-infected liver.

Awareness and opinions of non-alcoholic fatty liver disease by hospital specialists

BACKGROUND/AIM

Subjects with metabolic risk factors for non-alcoholic fatty liver disease (NAFLD) are commonly seen by hospital specialists other than gastroenterologists/hepatologists. The aim of this study was to assess the awareness of NAFLD and opinions regarding management among non-hepatologists at two major tertiary hospitals in Brisbane.

METHODS

A face-to-face questionnaire assessing current beliefs and practices regarding NAFLD was administered to specialists and specialists-in-training across six specialties (internal medicine, cardiology/cardiac surgery, endocrinology, thoracic medicine, rheumatology and nephrology).

RESULTS

One hundred clinicians were surveyed with 99% returning completed questionnaires (>89% questions answered). The majority of respondents (75%) believe the prevalence of NAFLD in the general population to be ≤ 10%, although two-thirds feel that its incidence will rise markedly. The vast majority (>90%) appreciate that traditional cardiovascular risk factors (obesity, hypertriglyceridaemia and diabetes) are risk factors for NAFLD and acknowledge that these are common in non-hepatology patients. Despite this, most believe that NAFLD is uncommon in their own patients (89% indicated a prevalence ≤ 30%). The vast majority (93%) agree that non-alcoholic steatohepatitis (NASH) is associated with increased overall mortality, but 60% also believe that simple steatosis confers increased liver-related mortality. Most (74%) agree that a diagnosis of NASH cannot be made using liver enzymes, but 67% support 6-monthly liver function tests as the most effective way to monitor progression of NAFLD. Most respondents (71%) make no referrals to hepatology for suspected NAFLD.

CONCLUSIONS

Non-hepatologists appreciate the seriousness of NAFLD but appear to underestimate its prevalence, especially among their own patients despite known risk factors. Attitudes regarding simple steatosis versus NASH and appropriate monitoring of suspected NAFLD suggest that more can be done to improve the understanding of this disease among non-hepatologists. This has implications for targeting 'at-risk' populations and appropriate referral of patients to hepatology clinics.

Successful immunotherapy of HCMV disease using virus-specific T cells expanded from an allogeneic stem cell transplant recipient

Opportunistic infection remains the principal cause of mortality in allogeneic stem cell transplant recipients with active extensive chronic graft-versus-host disease. Human cytomegalovirus (HCMV) represents an important cause of disease in this setting and the toxicity of protracted and recurrent antiviral treatment together with eventual drug resistance represents a significant limitation to therapy. Although the expansion and adoptive transfer of HCMV-specific T cells from the healthy original donor can be an effective strategy to control viral replication, this is not possible when donors are seronegative or are subsequently inaccessible. Here we demonstrate for the first time, the successful expansion of HCMV-specific T cells from a seropositive transplant recipient of a seronegative graft with active HCMV disease and the long-term reconstitution of protective antiviral immunity following their adoptive transfer back into the patient.

A combination of genetic polymorphisms increases the risk of progressive disease in chronic hepatitis C

BACKGROUND

There is increasing interest in the influence of host genetic factors on hepatic fibrosis, and whether genetic markers can reliably identify subjects at risk of developing severe disease. We hypothesised that hepatitis C virus (HCV) infected subjects with progressive fibrosis, classified using strict criteria based on histology at biopsy in addition to disease duration would be more likely to inherit several genetic polymorphisms associated with disease progression compared with subjects with a low rate of disease progression.

METHODS

We examined polymorphisms in eight genes that have been reported to have an association with hepatic fibrosis.

RESULTS

Associations between polymorphisms in six genes and more rapidly progressing fibrosis were observed, with individual adjusted odds ratios ranging from 2.1 to 4.5. The relationship between rapidly progressing fibrosis and possession of > or =3, > or =4, or > or =5 progression associated alleles was determined and the adjusted odds ratios increased with increasing number of progression associated alleles (9.1, 15.5, and 24.1, respectively). Using logistic regression analysis, a predictive equation was developed and tested using a second cohort of patients with rapidly progressing fibrosis. The predictive equation correctly classified 80% of patients in this second cohort.

CONCLUSIONS

This approach may allow determination of a genetic profile predictive of rapid disease progression in HCV and identify patients warranting more aggressive therapeutic management.

Non-response to antiviral therapy is associated with obesity and increased hepatic expression of suppressor of cytokine signalling 3 (SOCS-3) in patients with chronic hepatitis C, viral genotype 1

BACKGROUND

Interferon alpha (IFN-alpha) activated cellular signalling is negatively regulated by inhibitory factors, including the suppressor of cytokine signalling (SOCS) family. The effects of host factors such as obesity on hepatic expression of these inhibitory factors in subjects with chronic hepatitis C virus (HCV) are unknown.

OBJECTIVES

To assess the independent effects of obesity, insulin resistance, and steatosis on response to IFN-alpha therapy and to determine hepatic expression of factors inhibiting IFN-alpha signalling in obese and non-obese subjects with chronic HCV.

METHODS

A total of 145 subjects were analysed to determine host factors associated with non-response to antiviral therapy. Treatment comprised IFN-alpha or peginterferon alpha, either alone or in combination with ribavirin. In a separate cohort of 73 patients, real time-polymerase chain reaction was performed to analyse hepatic mRNA expression. Immunohistochemistry for SOCS-3 was performed on liver biopsy samples from 38 patients with viral genotype 1 who had received antiviral treatment.

RESULTS

Non-response (NR) to treatment occurred in 55% of patients with HCV genotypes 1 or 4 and 22% with genotypes 2 or 3. Factors independently associated with NR were viral genotype 1/4 (p < 0.001), cirrhosis on pretreatment biopsy (p = 0.025), and body mass index > or = 30 kg/m2 (p = 0.010). Obese subjects with viral genotype 1 had increased hepatic mRNA expression of phosphoenolpyruvate carboxy kinase (p = 0.01) and SOCS-3 (p = 0.047), in comparison with lean subjects. Following multivariate analysis, SOCS-3 mRNA expression remained independently associated with obesity (p = 0.023). SOCS-3 immunoreactivity was significantly increased in obesity (p = 0.013) and in non-responders compared with responders (p = 0.014).

CONCLUSIONS

In patients with chronic HCV viral genotype 1, increased expression of factors that inhibit interferon signalling may be one mechanism by which obesity reduces the biological response to IFN-alpha.

Characterization of tumour-infiltrating lymphocytes and apoptosis in colitis-associated neoplasia: comparison with sporadic colorectal cancer

The development of colorectal cancer is a major complication for patients with chronic idiopathic colitis. Colitis-associated tumours tend to occur at a younger age and be more aggressive than sporadic colorectal cancers. While we have previously associated the presence of tumour-infiltrating lymphocytes (TILs) and increased apoptosis in sporadic colorectal cancer with high-level microsatellite instability and improved prognosis, little is known of the relationship between these variables in colitis-associated colorectal cancer. The aim of this study was to correlate TILs and tumour cell apoptosis in colitis-associated neoplasms stratified according to microsatellite instability. Twenty tumour and 11 dysplastic samples resected from 21 patients with long-standing colitis were analysed for microsatellite instability at 10 microsatellite markers. TIL distribution (CD3, CD8) and function (granzyme B) were quantified by immunohistochemistry. Neoplastic cell apoptosis was assessed using the M30 CytoDEATH antibody. These findings were compared with 40 microsatellite stable (MSS) sporadic colorectal cancers previously evaluated for TILs and neoplastic apoptosis. Low-level microsatellite instability was found in 1/20 colitis-associated tumours. All other colitis-associated lesions were designated MSS. CD3(+) and CD8(+) TIL counts were significantly higher in colitis-associated lesions compared with MSS sporadic colorectal cancer (p < 0.0001, p = 0.001 respectively). Despite their higher TIL density, colitis-associated tumours were more likely to present late (Dukes' stage C or D) (p = 0.02). Functionally, colitis-associated TILs demonstrated significantly less granzyme B expression compared to sporadic cancers (p = 0.002). The level of tumour cell apoptosis was similar between the two groups (sporadic, 1.53%; colitis cancers, 1.45%). In conclusion, MSS colitis-associated tumours have a higher prevalence of CD3(+)/CD8(+) TILs but no associated increase in tumour cell killing by apoptosis. Unlike cytotoxic T cells in sporadic colorectal cancer, TILs do not appear to enhance the prognosis of colitis-associated colorectal cancer. This may be related to an impairment of granzyme B expression within these lesions.

CCR5-Delta32 mutation is strongly associated with primary sclerosing cholangitis

CCR5 plays a key role in the distribution of CD45RO+ T cells and contributes to generation of a T helper 1 immune response. CCR5-Delta32 is a 32-bp deletion associated with significant reduction in cell surface expression of the receptor. We investigated the role of CCR5-Delta32 on susceptibility to ulcerative colitis (UC), Crohn's disease (CD) and primary sclerosing cholangitis (PSC). Genotype and allelic association analyses were performed in 162 patients with UC, 131 with CD, 71 with PSC and 419 matched controls. There was a significant difference in CCR5 genotype (OR 2.27, P=0.003) between patients with sclerosing cholangitis and controls. Similarly, CCR5-Delta32 allele frequency was significantly higher in sclerosing cholangitis (17.6%) compared to controls (9.9%, OR 2.47, P=0.007) and inflammatory bowel disease patients without sclerosing cholangitis (11.3%, OR 1.9, P=0.027). There were no significant differences in CCR5 genotype or allele frequency between those with either UC or CD and controls. Genotypes with the CCR5-Delta32 variant were increased in patients with severe liver disease defined by portal hypertension and/or transplantation (45%) compared to those with mild liver disease (21%, OR 3.17, P=0.03). The CCR5-Delta32 mutation may influence disease susceptibility and severity in patients with PSC.

Nonalcoholic fatty liver disease: is all the fat bad?

Nonalcoholic fatty liver disease is now a major cause of liver disease in developed countries, largely as a result of an epidemic of obesity, diabetes and sedentary lifestyles. This has resulted in raised clinical awareness and diagnostic refinement. The entity encompasses several histologic patterns from benign steatosis to nonalcoholic steatohepatitis, the latter having a significant risk of progressive fibrosis and the development of cirrhosis. Laboratory tests and imaging are not able to distinguish steatosis from steatohepatitis, which requires liver biopsy. However following an assessment of several risk factors, patients can be stratified for the potential risk of fibrosis, allowing the rational use of liver biopsy. This review will describe the various patterns of nonalcoholic fatty liver disease and relate this to disease pathogenesis and progression. Strategies for management, including experimental interventions, will be discussed.

Modest weight loss and physical activity in overweight patients with chronic liver disease results in sustained improvements in alanine aminotransferase, fasting insulin, and quality of life

BACKGROUND AND AIM

Obesity is a risk factor for progression of fibrosis in chronic liver diseases such as non-alcoholic fatty liver disease and hepatitis C. The aim of this study was to investigate the longer term effect of weight loss on liver biochemistry, serum insulin levels, and quality of life in overweight patients with liver disease and the effect of subsequent weight maintenance or regain.

PATIENTS

Thirty one patients completed a 15 month diet and exercise intervention.

RESULTS

On completion of the intervention, 21 patients (68%) had achieved and maintained weight loss with a mean reduction of 9.4 (4.0)% body weight. Improvements in serum alanine aminotransferase (ALT) levels were correlated with the amount of weight loss (r = 0.35, p = 0.04). In patients who maintained weight loss, mean ALT levels at 15 months remained significantly lower than values at enrollment (p = 0.004), while in regainers (n = 10), mean ALT levels at 15 months were no different to values at enrollment (p = 0.79). Improvements in fasting serum insulin levels were also correlated with weight loss (r = 0.46, p = 0.04), and subsequent weight maintenance sustained this improvement. Quality of life was significantly improved after weight loss. Weight maintainers sustained recommended levels of physical activity and had higher fasting insulin levels (p = 0.03) at enrollment than weight regainers.

CONCLUSION

In summary, these findings demonstrate that maintenance of weight loss and exercise in overweight patients with liver disease results in a sustained improvement in liver enzymes, serum insulin levels, and quality of life. Treatment of overweight patients should form an important component of the management of those with chronic liver disease.

Effect of weight reduction on liver histology and biochemistry in patients with chronic hepatitis C

BACKGROUND

Steatosis occurs in more than 50% of patients with chronic hepatitis C and is associated with increased hepatic fibrosis. In many of these patients the pathogenesis of steatosis appears to be the same as for patients with non-alcoholic fatty liver disease-that is, related to visceral adiposity and obesity.

METHODS

The effect of a three month weight reduction programme on liver biochemistry and metabolic parameters was examined in 19 subjects with steatosis and chronic hepatitis C. Paired liver biopsies were performed in 10 subjects, prior to and 3-6 months following the intervention, to determine the effect of weight loss on liver histology.

RESULTS

There was a mean weight loss of 5.9 (3.2) kg and a mean reduction in waist circumference of 9.0 (5.0) cm. In 16 of the 19 patients, serum alanine aminotransferase levels fell progressively with weight loss. Mean fasting insulin fell from 16 (7) to 11 (4) mmol/l (p<0.002). Nine of 10 patients with paired liver biopsies had a reduction in steatosis irrespective of viral genotype. In these subjects the median modified Knodell fibrosis score decreased from 3 to 1 (p=0.04) and activated stellate cells significantly decreased (p<0.004).

CONCLUSIONS

Weight loss in patients with chronic hepatitis C may be associated with a reduction in steatosis and abnormal liver enzymes and an improvement in fibrosis, despite the persistence of the virus. Weight reduction may provide an important adjunct treatment strategy for patients with chronic hepatitis C.

Timely topic: Premalignant lesions associated with adenocarcinoma of the upper gastrointestinal tract

The changing incidence of adenocarcinomas, particularly in the oesophagus and gastric cardia, has led to the rapid expansion of screening programmes aimed at detecting the precursor lesion of dysplasia before adenocarcinoma develops. The pathologist now has an important role in first diagnosing patients at risk for developing dysplasia, and then correctly classifying dysplasia when it occurs. Barrett's oesophagus has had different diagnostic criteria in previous years but is currently diagnosed by the presence of intestinal metaplasia of any length in the true oesophagus. Intestinal metaplasia confined only to the gastro-oesophageal junction or cardia is of uncertain significance but is probably common, with less risk of progressing to dysplasia or malignancy. In the stomach, patients with autoimmune atrophic gastritis and Helicobacter-associated multifocal atrophic gastritis have an increased risk of adenocarcinoma, but screening protocols are not well-developed compared with those used for Barrett's oesophagus. Dysplasia of glandular epithelium can be classified using well-described criteria. Low grade dysplasia is the most common type and regresses or remains stable in the majority of patients. High grade dysplasia is more ominous clinically, with a propensity to coexist with or progress to adenocarcinoma.

Angiotensin-converting enzyme inhibition attenuates the progression of rat hepatic fibrosis

BACKGROUND AND AIMS

There is a significant relationship between inheritance of high transforming growth factor (TGF)-beta1 and angiotensinogen-producing genotypes and the development of progressive hepatic fibrosis in patients with chronic hepatitis C. In cardiac and renal fibrosis, TGF-beta1 production may be enhanced by angiotensin II, the principal effector molecule of the renin-angiotensin system. The aim of the present study was to determine the effects of the angiotensin-converting enzyme inhibitor, captopril, on the progression of hepatic fibrosis in the rat bile duct ligation model.

METHODS

Rats were treated with captopril (100 mg. kg(-1). day(-1)) commencing 1 or 2 weeks after bile duct ligation. Animals with bile duct ligation only and sham-operated animals served as controls. Four weeks after bile duct ligation, indices of fibrosis were assessed.

RESULTS

Captopril treatment significantly reduced hepatic hydroxyproline levels, mean fibrosis score, steady state messenger RNA levels of TGF-beta1 and procollagen alpha1(I), and matrix metalloproteinase 2 and 9 activity.

CONCLUSIONS

Captopril significantly attenuates the progression of hepatic fibrosis in the rat bile duct ligation model, and its effectiveness should be studied in human chronic liver diseases associated with progressive fibrosis.

Role of cytokine gene polymorphisms in acute rejection and renal impairment after liver transplantation

Although immunosuppressive regimens are effective, rejection occurs in up to 50% of patients after orthotopic liver transplantation (OLT), and there is concern about side effects from long-term therapy. Knowledge of clinical and immunogenetic variables may allow tailoring of immunosuppressive therapy to patients according to their potential risks. We studied the association between transforming growth factor-beta, interleukin-10, and tumor necrosis factor alpha (TNF-alpha) gene polymorphisms and graft rejection and renal impairment in 121 white liver transplant recipients. Clinical variables were collected retrospectively, and creatinine clearance was estimated using the formula of Cockcroft and Gault. Biallelic polymorphisms were detected using polymerase chain reaction-based methods. Thirty-seven of 121 patients (30.6%) developed at least 1 episode of rejection. Multivariate analysis showed that Child-Pugh score (P =.001), immune-mediated liver disease (P =.018), normal pre-OLT creatinine clearance (P =.037), and fewer HLA class 1 mismatches (P =.038) were independently associated with rejection. Renal impairment occurred in 80% of patients and was moderate or severe in 39%. Clinical variables independently associated with renal impairment were female sex (P =.001), pre-OLT renal dysfunction (P =.0001), and a diagnosis of viral hepatitis (P =.0008). There was a significant difference in the frequency of TNF-alpha-308 alleles among the primary liver diseases. After adjustment for potential confounders and a Bonferroni correction, the association between the TNF-alpha-308 polymorphism and graft rejection approached significance (P =.06). Recipient cytokine genotypes do not have a major independent role in graft rejection or renal impairment after OLT. Additional studies of immunogenetic factors require analysis of large numbers of patients with appropriate phenotypic information to avoid population stratification, which may lead to inappropriate conclusions.

Steatosis and chronic hepatitis C: analysis of fibrosis and stellate cell activation

BACKGROUND/AIMS

Steatosis is a frequent histological finding in chronic hepatitis C and is associated with increased hepatic fibrosis.

METHODS

We studied 80 patients with untreated chronic hepatitis C to determine whether steatosis contributes to fibrosis through a steatohepatitis-like pathway.

RESULTS

Fine sinusoidal and/or central vein fibrosis was present in 52 patients (65%). This was typically located in acinar zone 3 and had a chicken-wire appearance similar to that seen in steatohepatitis. A statistically significant relationship was found between subsinusoidal fibrosis and age (r(s) = 0.33, P = 0.003) and grade of steatosis (r(s) = 0.35, P = 0.001). Mean body mass index was higher in patients with focal (28.4 +/- 4.7 kg/m2) or extensive (29.6 +/- 5.9 kg/m2) subsinusoidal fibrosis than in those patients with no subsinusoidal fibrosis (25.5 +/- 3.7 kg/m2). The extent of alpha-smooth muscle actin staining (as a marker of stellate cell activation) correlated with the degree of portal inflammation and the stage of portal fibrosis, but not with the grade of hepatic steatosis.

CONCLUSIONS

These findings suggest that in hepatitis C infection, host factors, particularly adiposity, contribute to both steatosis and acinar fibrosis. The implication of these observations is that weight reduction may provide an important therapeutic strategy for patients with chronic hepatitis C.

Fibrous obliterative lesions of veins contribute to progressive fibrosis in chronic liver allograft rejection

Fibrosis in liver allografts undergoing chronic rejection (CR) is variable and poorly understood. The temporal and spatial relationships of venous, arterial, and biliary lesions were studied to clarify their potential contributions to graft fibrosis. The severity, prevalence, and morphology of intimal lesions of vessels were analyzed and compared with the fibrosis stage. Three groups were found; group 1 (n = 5) with no hepatic vein (HV) lesions, group 2 (n = 5) with HV lesions only, and group 3 with lesions of both HV and portal veins (PV). The earliest lesion to develop, in 71% of grafts, was concentric intimal thickening of small HV. This was significantly more severe and frequent in grafts from group 3. With increasing frequency and severity of small HV sclerosis, fibrosis developed in medium/large veins. The morphology of larger vessel lesions suggested organized thrombus. Centrilobular fibrosis was significantly more severe in group 3 and developed unpredictably and sometimes rapidly. Conversely, portal fibrosis scores were significantly higher in grafts with ductular proliferation and did not correlate with venous lesions. This suggests that in CR, veno-occlusive-like lesions develop commonly in terminal hepatic venules, probably caused by immune-mediated damage. In only a proportion, with increased frequency and severity of the lesions, stasis and thrombosis in portal and larger veins occur and could result in loss of hepatic and portal venous outflow, which leads to ischemia and fibrosis. The stage of fibrosis did not correlate with foam-cell arteriopathy. A second pathway of portal fibrosis occurs in patients with longstanding biliary proliferation.

Increased hepatic iron and cirrhosis: no evidence for an adverse effect on patient outcome following liver transplantation

It has been suggested that preexisting severe hepatic iron overload may adversely affect outcome after liver transplantation. The pathogenesis of iron overload in cirrhosis in the absence of hemochromatosis gene (HFE) mutations is poorly understood. The relationships between liver disease severity and etiology, degree of hepatic iron overload, and post-liver transplantation outcome were studied in 282 consecutive adult patients with cirrhosis. Thirty-seven percent of patients had stainable hepatic iron. Increased hepatic iron concentration was significantly associated with more severe liver disease (P<.001), male sex (P = .05), the presence of spur cell anemia (P<.0001), and hepatocellular liver disease (P<.0001). The HFE mutations were uncommon in patients with increased hepatic iron stores. Increased hepatic iron concentration was not associated with greater utilization of resources or a lower survival after liver transplantation. Child-Pugh score at the time of liver transplantation was the only independent variable affecting patient survival (P = .0008). In summary, our data suggest that the severity of the liver disease rather than hepatic iron concentration is the most important determinant of outcome after liver transplantation and that, in general, increasing hepatic iron concentration in cirrhosis is a surrogate marker of the severity of the underlying liver disease.

Detection of male DNA in the liver of female patients with primary biliary cirrhosis

BACKGROUND/AIMS

Primary biliary cirrhosis is a chronic cholestatic liver disease characterized by progressive inflammatory destruction of bile ducts, with eventual hepatic fibrosis and cirrhosis. Since primary biliary cirrhosis affects predominantly middle-aged women and has pathological similarities to hepatic graft-versus-host-disease, we investigated whether fetal cell microchimerism might be involved in the development of this disease.

METHODS

The presence of Y-chromosome-specific sequences was analyzed by polymerase chain reaction using peripheral blood mononuclear cells from women with primary biliary cirrhosis (n=18) and healthy (control) women (n=18), and by in situ hybridization of liver biopsy sections from women with primary biliary cirrhosis (n=19) and women with chronic hepatitis C or alcoholic liver disease (n=20).

RESULTS

Male cells were detected in liver biopsy specimens of 8 of 19 patients (42%) with primary biliary cirrhosis. Y-chromosome-containing cells were not seen in any of the liver biopsy specimens from women with chronic hepatitis C or alcoholic liver disease. Male cells were detected in peripheral blood mononuclear cells from one healthy control at a level of 1 male cell per 10(6) female cells, but were not detected in peripheral blood mononuclear cells of women with primary biliary cirrhosis.

CONCLUSIONS

The presence of male cells in the liver of women with primary biliary cirrhosis raises the possibility that fetal cell microchimerism may be involved in the pathogenesis of this chronic liver disease.

Clinicopathological analysis of liver allograft biopsies with late centrilobular necrosis: a comparative study in 54 patients

BACKGROUND

Centrilobular necrosis (CLN) in liver allografts can be a difficult lesion to interpret histologically. Although long recognized in association with developing chronic rejection, recent studies have described the lesion in association with a number of other disease processes. To clarify the histologic features that could allow a specific diagnosis to be made and to determine the outcome in different diagnostic groups, we assessed biopsies from 54 patients with CLN.

METHODS

Biopsies were classified as CLN with acute cellular rejection (ACR), CLN with hepatitis, CLN with developing chronic rejection (CR), and CLN of other etiology. Histologic features were assessed and then compared between groups, and clinical outcomes were noted.

RESULTS

Discriminating features for the different groups were as follows: CLN and ACR showed bile duct injury, endothelialitis, and acinar congestion. CLN and CR showed severe bile duct injury, bile duct loss, or centrilobular swelling. CLN and hepatitis was often a diagnosis of exclusion, although interface hepatitis was more common in this group. Cases of autoimmune hepatitis usually demonstrated plasma cell predominance in the portal and acinar inflammatory infiltrate. Significantly, there was considerable overlap in the histologic features between the groups, accounting for the diagnostic difficulty. Patients in whom the CLN was associated with CR or vascular complications generally required retransplantation or died, but in the groups with ACR and hepatitis, the outcome was more favorable.

CONCLUSIONS

With regard to most liver allograft biopsies showing late CLN, it is possible to make a specific diagnosis despite overlapping histologic features; this allows specific therapy to be instituted. Ultimately this is likely to contribute to improved graft survival.

Host genetic factors influence disease progression in chronic hepatitis C

Progressive hepatic fibrosis and cirrhosis develops in 20% to 30% of patients with chronic hepatitis C virus (HCV). We propose that host genetic factors influencing fibrogenesis may account for some of the variability in progression of this disease. In progressive fibrosis of other organs, particularly heart and kidney, production of the profibrogenic cytokine, transforming growth factor beta1 (TGF-beta1), may be enhanced by angiotensin II, the principal effector molecule of the renin-angiotensin system. The inheritance of polymorphisms in TGF-beta1, interleukin 10 (IL-10), tumor necrosis factor alpha (TNF-alpha), and genes of the renin-angiotensin system was examined in 128 patients with chronic HCV. The influence of genotypes on the stage of hepatic fibrosis was tested after adjustment for potential confounders (age, gender, alcohol consumption, portal inflammation, and steatosis), which may have independent effects on histological severity. The stage of fibrosis was 0 in 30 (23.4%), 1 in 44 (34.4%), 2 in 27 (21.1%), and 3 or 4 in 27 (21.1%). A statistically significant relationship was seen between inheritance of high TGF-beta1- and angiotensinogen (AT)-producing genotypes and the development of progressive hepatic fibrosis. This association persisted after correcting for potential confounders. Patients who inherited neither of the profibrogenic genotypes had no or only minimal fibrosis. Knowledge of these polymorphisms may have prognostic significance in patients with chronic HCV and may direct more aggressive therapy towards those patients with an increased risk of disease progression. The documentation of a significant relationship between AT genotype and fibrosis raises the novel suggestion that angiotensin II may be another mediator of extracellular matrix production in the liver.

Clinicopathologic findings of recurrent primary sclerosing cholangitis after orthotopic liver transplantation

Whether primary sclerosing cholangitis (PSC) occurs after orthotopic liver transplantation is controversial, largely because the pre-transplant diagnosis of PSC is based on nonspecific radiological and histological findings. We reviewed clinical, radiological, and histological records of 53 patients who underwent liver transplantation for PSC between 1985 and 1998. Three patients with patent hepatic arteries and no evidence of chronic rejection had radiological and histological findings that may have been due to recurrent PSC. Bile duct stricturing in these patients proved permanent and progressive and affected both the quality of life and graft survival. The first patient, who is 110 months after transplantation, has had repeated episodes of cholangitis for the last year. The second patient underwent excision of a strictured hepatic duct 45 months after transplantation and was ultimately retransplanted 95 months after initial transplantation. The third patient underwent left hemihepatectomy of an atrophied lobe 50 months after transplantation. Although the patient population assessed in this study is limited, putative recurrent PSC in the allografts has led either to graft loss or to clinically significant hepatobiliary complications of the graft.

Expression of cytokines and factors modulating apoptosis by human sinusoidal leucocytes

BACKGROUND/AIMS

Liver sinusoids contain a large population of spontaneously cytotoxic cells (NK cells), CD8+ T cells and macrophages. The physiological role of these leucocytes remains unclear. They may participate in immune surveillance and peripheral tolerance by deleting tumour cells, virus-infected cells and activated T cells as they traffic through the liver. In order to gain further information about the function of these leucocytes within the hepatic sinusoids, we examined their production of immunomodulatory cytokines and apoptosis-related molecules.

METHODS

Semi-quantitative polymerase chain reaction and immunohistochemistry were used to determine the spontaneous production of cytokines and apoptosis-related molecules by sinusoidal leucocytes isolated from donor liver preservation solution.

RESULTS

In comparison with matched peripheral blood mononuclear cells, sinusoidal leucocytes produced more mRNA for IL-10, IL-15, TNF-alpha, IL-18, IFN-gamma, FasL, perforin and granzyme. IL-4 and IL-12 were not detected and IL-2 was only faintly detected in the liver-derived CD4+ population. Less bcl-2 was expressed in liver-derived CD4+ and CD8+ cells in comparison with matched peripheral blood cell populations.

CONCLUSIONS

The cytokines produced spontaneously by sinusoidal leucocytes are consistent with their high level of activation and spontaneous cytotoxicity. Their strong expression of apoptosis-mediating molecules (FasL, perforin, granzyme and TNF-alpha) support a role for these cells in immune surveillance and peripheral tolerance induction.

Case report: lamivudine therapy for submassive hepatic necrosis due to reactivation of hepatitis B following chemotherapy

This report describes the case of a 53-year-old woman who developed severe hepatitis following chemotherapy for breast carcinoma. The patient was hepatitis B surface antigen positive, e antigen negative and e antibody positive and had high levels of hepatitis B virus-DNA. Liver biopsy revealed submassive hepatic necrosis, consistent with reactivation of hepatitis B. Treatment with lamivudine resulted in rapid loss of hepatitis B virus-DNA, resolution of hepatitis and clinical recovery.

Role of donor leukocyte chimerism in establishing the etiology of neutropenia after liver transplantation

BACKGROUND

The quantitation of donor leukocyte chimerism may aid in establishing the etiology of neutropenia after liver transplantation.

METHODS

The incidence and clinical and laboratory characteristics of severe neutropenia were studied in adults who have undergone liver transplantation at our institution over the last 4 years.

RESULTS

Severe neutropenia developed in 5 of 156 patients (3%). The clinical and pathological features were nonspecific. In two patients with a delayed diagnosis of graft-versus-host disease (GVHD), donor leukocytes comprised > or = 50% of the circulating peripheral blood mononuclear cells. In a third patient, an earlier diagnosis of GVHD was suspected on the basis of a donor leukocyte count of 3-10% in the peripheral blood. In contrast, donor leukocyte chimerism was < or = 0.01% in two patients with probable drug-induced neutropenia

CONCLUSIONS

The determination of donor leukocyte chimerism has an important role in the investigation of neutropenia after liver transplantation, allowing early diagnosis and treatment of GVHD.

Peripheral blood chimerism following human liver transplantation

The aim of this study was to prospectively investigate the peak levels and kinetics of donor leucocyte chimerism in human recipients following liver transplantation. The peak levels of chimerism were observed within the first 48 hours following transplantation and ranged from 0.15% to 20% of total peripheral blood mononuclear cells. In all but one patient, who developed graft versus host disease, there was an early peak level of chimerism that declined over time such that donor leukocytes were only intermittently detectable after 3 to 4 weeks. In 8 patients who had no episodes of graft rejection, the peak level of donor leukocyte chimerism ranged from 1.3% to 20% (mean +/- SEM; 5.5% +/- 2.1%). In 3 patients who were treated for episodes of acute graft rejection during the first four postoperative weeks, the peak level of donor leukocyte chimerism ranged from 0.15% to 0.2% (0.18 +/- 0.02, P = .012). The results demonstrate a marked variation in the total number of donor leukocytes detectable in the peripheral blood early after liver transplantation and also, that lower levels of chimerism may be associated with lower rates of initial graft acceptance and a higher incidence of acute rejection.

Evidence that "myofibroblast-like" cells are the cellular source of capsular collagen in hepatocellular carcinoma

BACKGROUND/AIMS

The prognosis for patients with hepatocellular carcinoma is poor although tumour encapsulation has been associated with improved survival and disease-free rates. While the source of the tumour capsule is unclear, the major role that activated hepatic stellate cells play in the deposition of liver matrix in normal and diseased states suggests the possible involvement of these cells in tumour encapsulation.

METHODS

Twenty-four liver tumours (seven encapsulated HCC, seven non-encapsulated HCC, 10 colorectal metastases) were studied. Activated hepatic stellate cells were identified by immunohistochemistry for alpha-smooth muscle actin (alpha-SMA) and in situ hybridization for pro-collagen alpha1 (I) mRNA. Collagen deposition was localized using Masson's trichrome stain.

RESULTS

Pro-collagen alpha1 (I) mRNA co-localized to alpha-SMA positive hepatic stellate cells within the region of increased collagen deposition in (i) the tumour capsule of encapsulated HCC, and (ii) the tumour junction of non-encapsulated HCC and colorectal metastasis. In addition, there was marked peritumour expression of alpha-SMA and procollagen alpha1 (I) mRNA, which diminished with distance away from the tumour in all tumour groups. The degree of expression was greatest with encapsulated HCC, less with non-encapsulated HCC and least with colorectal metastasis. This contrasted with the absence of alpha-SMA expression in normal liver from the same patients. Within the tumours, colorectal metastases differed from HCC by demonstrating marked alpha-SMA expression and collagen deposition in the septa.

CONCLUSIONS

Our findings demonstrate that activated hepatic stellate cells (i) are responsible for increased peritumour collagen production in non-encapsulated HCC and colorectal metastasis, and (ii) may be implicated in tumour capsule formation in HCC and metastasis stroma development. Thus, stellate cells may influence the local hepatic invasion by these tumours.

Eosinophilic enteritis in northeastern Australia. Pathology, association with Ancylostoma caninum, and implications

While eosinophilic gastroenteritis is considered a rare condition, eosinophilic enteritis without gastric involvement is quite common in northeastern Australia. We present 79 patients with biopsy-proven eosinophilic enteritis, 70 seen since 1987. In 10 patients, eosinophilic enteritis was associated with infection by single, sexually immature, adult hookworms, most positively identified as the common dog hookworm Ancylostoma caninum. An additional 22 patients (of 34 tested) had serological evidence of A. caninum exposure. The essential pathology, i.e., edema and eosinophilic infiltration of the gut wall, ascites, and regional lymphadenopathy, was identical to that seen in eosinophilic gastroenteritis. Additional, more specific features included pathological reactions centered on attached worms, mucosal alterations and ulcers considered to be hookworm bite sites, and submucosal and lymph node granulomas with central eosinophil degranulation and degradation products. Since A. caninum has an almost worldwide distribution, it is probable that A. caninum-induced eosinophilic enteritis occurs outside Australia. We show that the worm is easily overlooked in pathological specimens and that care is required to preserve worms intact for specific parasitological identification. The clinical and pathological features were similar to those seen in another human enteric helminthic zoonosis, anisakiasis. The possibility that there are yet other undiscovered intestinal zoonoses remains.

Parasitic origin of a solitary necrotic nodule of the liver

Images