Severe steatosis as the initial histologic manifestation of recurrent hepatitis C genotype 3

Safe use of highly steatotic livers by utilizing a donor/recipient clinical algorithm

The aim of this study was to assess the long-term safety and clinical outcomes associated with the utilization of highly steatotic donor livers utilizing a specific donor/recipient matching algorithm. This was a prospective, observational, single-center, 10-yr follow-up study. Highly steatotic livers were utilized according to a donor/recipient algorithm that guided the surgeon to use highly steatotic donor organs judiciously in low-risk recipients. This study initially compared fat assessment based on frozen-section Ehrlich's hematoxylin and eosin (H&E) to reperfusion biopsy fat assessment and demonstrated that H&E is an insensitive analysis to determine degree of steatosis. Patients were divided into three groups based on donor steatosis (group 1: <30% steatosis, group 2: 30-60% steatosis, group 3: >60% steatosis), and clinical outcomes were assessed. One hundred and sixteen patients were included in the analysis. Patients that received severely steatotic livers (>60% fat) showed increased reperfusion liver injury and delayed return of liver function in the early postoperative period, demonstrated by biochemical markers. However, there were no differences in primary non-function, postoperative complications, length of stay, and patient and graft survival. Using rigorous donor/recipient matching through a detailed algorithm, these data demonstrate that normal liver allograft outcomes are not superior to those in highly steatotic grafts.

What is expected from the pathologist in the diagnosis of viral hepatitis?

The clinician expects from the pathologist a clinically relevant diagnosis on the basis of liver biopsy interpretation. Today, a liver biopsy, as invasive procedure, is only justified when a significant benefit for the patient can be expected particularly with respect to the clinical management. Consequently, liver biopsy is usually not required in uncomplicated acute viral hepatitis. It is, however, an important diagnostic tool in chronic hepatitis and in transplanted liver to confirm the clinical diagnosis and to assess stage and grade of necroinflammation, treatment efficiency, and concurrent diseases. The diagnosis of liver disease is based on teamwork between clinician and pathologist. Evaluation of the biopsy in the clinical context requires clinical information and appropriate size and handling of the biopsy specimen. Aim of this review is the discussion of morphologic features of acute and chronic viral hepatitis with regard to their clinical relevance.

Hepatitis C virus: How genetic variability affects pathobiology of disease

As an RNA virus, hepatitis C virus (HCV) shows a characteristically high level of nucleotide diversity. Accumulation of nucleotide substitutions in the virus has resulted in diversification into quasispecies, subtypes and distinct genotypes. Pathobiological studies linking nucleotide and amino acid sequences with clinical findings have identified relationships between certain genotypes and characteristic biological properties. Genotype 3 HCV infection was found to be associated with a high level of liver steatosis. Genotypes 1 and 4 were found to be more resistant to interferon (IFN) based therapies than genotypes 2 and 3. Studies of genotype 1 sequences obtained from patients treated with IFN have identified a relationship between favorable response to interferon therapy and amino acid substitutions in the NS5A region (interferon response determining region; ISDR). Further studies have identified a relationship between the effect of IFN therapy and other regions of the NS5A protein. More recently, a relationship has been found between poor response to peg-IFN plus ribavirin combination therapy and substitutions at amino acid 70 and 91 in the core protein. Furthermore, a correlation between human genetic variation in the IL28B (IFN-lamda 3) locus and core amino acid substitutions has been characterized. In this review we briefly summarize the discovery, classification and nomenclature of HCV genotypes and subtypes. We also discuss amino acid substitutions within specific regions that have been reported to be associated with outcome of IFN and peg-IFN plus ribavirin combination therapy.

Liver biopsy assessment in chronic hepatitis

Liver biopsy has been a major diagnostic tool in the evaluation of individuals with chronic hepatitis for many decades and remains the most direct way of visualizing hepatic necroinflammation and fibrosis. In chronic viral hepatitis B and C, immune attack on hepatocytes bearing viral antigens results in the entry of lymphocytes and other effector cells through the portal tracts from which other lesions may evolve, including interface and lobular hepatitis as well as fibrosis or cirrhosis. Classification systems have been developed in order to provide semiquantitative grading of necroinflammation and staging of fibrosis and include the Scheuer, Batts and Ludwig, Ishak, and METAVIR systems. This review provides an historical perspective on histopathological methods of analyzing chronic hepatitis, describes the essential criteria of each of the major scoring systems and discusses problems related to sampling error, observer variation, and specimen size.

Management of hepatitis C infection after liver transplantation

Recurrent hepatitis C virus (HCV) infection after orthotopic liver transplantation (OLT) has been associated with progression to cirrhosis in approximately 20% of patients, 5 years postoperatively. Accelerated decompensation has also been noted when compared with cirrhosis in non-transplant patients. Different treatment strategies are available for recurrent HCV infection post-OLT, but efforts are hindered by the modest response rates, poor tolerability and the risk of rejection as well as graft loss. Anti-HCV immunoglobulin therapy to prevent graft infection with HCV has no established role at present but studies are ongoing. Treatment prior to transplantation in patients with decompensated cirrhosis has been evaluated but the results are too preliminary to make firm recommendations. Prophylactic interferon-based antiviral therapy in the early postoperative period to prevent graft infection was shown to have low response rates and high rates of adverse effects. Treatment of established recurrent HCV infection with combination peginterferon (pegylated interferon) and ribavirin is associated with 10-59% sustained virological response and the predictive value of a positive early virological response has been validated in the post-transplant setting. Improvement in inflammatory activity after viral eradication is well established, but fibrosis regression or stabilisation is less predictable and factors such as rejection and biliary complications may still contribute to graft loss. Most studies have initiated therapy at least 6 months postoperatively in order to optimise patient tolerance and enable the addition of ribavirin. The use of adjuvant agents to treat drug-induced neutropenia and anaemia in this population is evolving and becoming a crucial part of therapy. Determination of optimal doses of both pegylated interferon and ribavirin, and guidance on when to stop treatment, as well as improving tolerability are important steps in achieving higher response rates and minimising drug toxicity.

Liver transplantation in HIV-HCV coinfected patients: a case-control study

Liver transplantation (LT) for hepatitis C virus (HCV)-associated cirrhosis in human immunodeficiency virus (HIV)-infected patients was compared with non-HIV patients. Nine patients with HIV-HCV coinfection were compared with patients transplanted before and after each HIV patient (control group). Immunosuppression consisted in tacrolimus with steroids or mycophenolate mofetil. Acute cellular rejection and three-year actuarial patient survival were respectively 44% and 87.5% in HIV group and 22% and 93.7% in the control group (P=NS). Acute hepatitis C virus occurred earlier (2.3 vs. 4.3 months) and was more cholestatic (mean bilirubin: 10.8 vs. 1.6 mg/dL) in the HIV group. Eight (100%) HIV and nine (64.3%) control patients received antiviral treatment with pegylated interferon and ribavirin. One patient (11.1%) of the control group and one patient (20%) of the HIV group presented a sustained virologic response (P=NS). Short- to midterm results of LT in HIV-HCV co-infected patients were excellent and similar to non-HIV patients.

Liver biopsy interpretation for causes of late liver allograft dysfunction

Evaluation of needle biopsies and extensive clinicopathological correlation play an important role in the determination of liver allograft dysfunction occurring more than 1 year after transplantation. Interpretation of these biopsies can be quite difficult because of the high incidence of recurrent diseases that show histopathological, clinical, and serological features that overlap with each other and with rejection. Also, more than one insult can contribute to allograft injury. In an attempt to enable centers to compare and pool results, improve therapy, and better understand pathophysiological disease mechanisms, the Banff Working Group on Liver Allograft Pathology herein proposes a set of consensus criteria for the most common and problematic causes of late liver allograft dysfunction, including late-onset acute and chronic rejection, recurrent and new-onset viral and autoimmune hepatitis, biliary strictures, and recurrent primary biliary cirrhosis and primary sclerosing cholangitis. A discussion of differential diagnosis is also presented.

Hepatobiliary pathology

PURPOSE OF REVIEW

This review highlights recent publications on hepatobiliary pathology concerning several unusual types of hepatitis, fatty liver disease, disorders of the biliary tree and other topics that have a substantial impact on liver biopsy interpretation.

RECENT FINDINGS

In the outbreak of severe acute respiratory syndrome (SARS), many patients had abnormalities in liver function tests. Liver biopsy findings in three cases were reported that showed a generic picture of hepatitis, with exceptionally increased mitotic activity. The role of portal myofibroblasts in cirrhosis was examined in several studies. A newly described lesion, isolated ductular hyperplasia (IDH) was found in patients with prolonged abnormalities of liver function tests of uncertain origin. Hyperplastic, well-differentiated bile ductules were seen on liver biopsy in the absence of any identifiable biliary disease. Hereditary hemochromatosis is now a complex entity with various clinicopathological forms based on mutations in the HFE gene and other iron-homeostatic genes such as transferrin receptor 2 and ferroportin 1. In some of these heritable forms of primary iron overload, stainable iron is present in both hepatocytes and Kupffer cells. After liver transplantation, differentiating recurrent HCV infection from acute rejection on liver biopsy is problematic, with exceptionally low inter- and intra-observer reliability shown in one study.

SUMMARY

The hepatitis associated with the SARS coronavirus, Isolated Ductular Hyperplasia in patients with liver function test abnormalities and other topics with pathologic relevance are reviewed.