Cirrhosis after orthotopic liver transplantation in the absence of primary disease recurrence

COVID-19 and severity of liver diseases: Possible crosstalk and clinical implications

COVID-19-infected individuals and those who recovered from the infection have been demonstrated to have elevated liver enzymes or abnormal liver biochemistries, particularly with preexisting liver diseases, liver metabolic disorders, viral hepatitis, and other hepatic comorbidities. However, possible crosstalk and intricate interplay between COVID-19 and liver disease severity are still elusive, and the available data are murky and confined. Similarly, the syndemic of other blood-borne infectious diseases, chemical-induced liver injuries, and chronic hepatic diseases continued to take lives while showing signs of worsening due to the COVID-19 crisis. Moreover, the pandemic is not over yet and is transitioning to becoming an epidemic in recent years; hence, monitoring liver function tests (LFTs) and assessing hepatic consequences of COVID-19 in patients with or without liver illnesses would be of paramount interest. This pragmatic review explores the correlations between COVID-19 and liver disease severity based on abnormal liver biochemistries and other possible mechanisms in individuals of all ages from the emergence of the COVID-19 pandemic to the post-pandemic period. The review also alludes to clinical perspectives of such interactions to curb overlapping hepatic diseases in people who recovered from the infection or living with long COVID-19.

Quantification of extracellular matrix remodeling for the non-invasive identification of graft fibrosis after liver transplantation

Detecting patients with early post-transplant fibrosis after liver transplantation (LT) is very important. Non-invasive tests are needed to avoid liver biopsies. We aimed to detect fibrosis in liver transplant recipients (LTR) using extracellular matrix (ECM) remodeling biomarkers. ECM biomarkers for type III (PRO-C3), IV (PRO-C4), VI (PRO-C6) and XVIII (PRO-C18L) collagen formation and type IV collagen degradation (C4M) were measured by ELISA in prospectively collected, cryopreserved plasma samples (n = 100) of LTR with paired liver biopsies from a protocol biopsy program. Fibrosis ≥ F2 was present in 29% of patients (median 44 months post-LT). APRI and FIB-4 neither identified significant fibrosis nor were correlated with histopathological fibrosis scores, while ECM biomarkers (AUCs 0.67-0.74) did. The median levels of PRO-C3 (15.7 vs. 11.6 ng/ml; p = 0.002) and C4M (22.9 vs. 11.6 ng/ml; p = 0.006) levels were elevated in T-cell-mediated rejection compared to normal graft function. The median levels of PRO-C4 (178.9 vs. 151.8 ng/ml; p = 0.009) and C4M (18.9 vs. 16.8 ng/ml; p = 0.004) levels were increased if donor-specific antibodies were present. PRO-C6 had the highest sensitivity (100%), NPV (100%) and negative likelihood-ratio (0) for graft fibrosis. To conclude, ECM biomarkers are helpful in identifying patients at risk of relevant graft fibrosis.

Prediction of long-term morbidity and mortality after liver transplantation using two-dimensional shear wave elastography compared with liver biopsy

The role of noninvasive liver disease assessment by two-dimensional shear wave elastography (2D-SWE) to diagnose fibrosis is well described in patients with chronic liver disease. However, its role in prognosis, especially after liver transplantation (LT) has not been adequately examined. We hypothesized that elevated liver stiffness measurement (LSM) as measured by 2D-SWE after LT predicts future morbidity and mortality independent of fibrosis by liver biopsy. In a prospective cohort study, consecutive LT recipients underwent concomitant protocol 2D-SWE and protocol liver biopsy (2012-2014), with the assessor blinded to biopsy findings. We examined the baseline correlation of LSM with fibrosis stage and the association between elevated LSM and the development of subsequent clinical outcomes and all-cause mortality. A total of 187 LT recipients (median age 58 years, 38.5% women, median body mass index 26.5 kg/m² , 55.1% hepatitis C virus, 17.6% nonalcoholic steatohepatitis/cryptogenic) were examined. Median time between LT and biopsy/2D-SWE assessment was 4.0 years, and the median follow-up time after LSM determination was 3.5 years. Median LSM was 9 kPa (8 kPa [F0/F1], 11.5 kPa [F2], 12 kPa [F3/F4]). There was a positive correlation between LSM and fibrosis stage (r_s  = 0.41; p < 0.001). LSM ≥11 kPa was associated with lower survival within 3 years (84.8 vs. 93.7%; p = 0.04). After adjusting for age, sex, and fibrosis stage, LSM ≥11 kPa was independently associated with mortality (hazard ratio, 2.45; 95% confidence interval, 1.08-5.60). Elevated LSM by 2D-SWE is associated with increased mortality after LT independent of hepatic fibrosis. Given the overall decrease in the use of liver biopsy in the current era, 2D-SWE may serve as a novel noninvasive prognostic tool to predict relevant outcomes late after LT.

Long-term liver allograft fibrosis: A review with emphasis on idiopathic post-transplant hepatitis and chronic antibody mediated rejection

Liver transplantation (LT) is a life-saving surgical procedure and the current standard of care for most patients with end stage liver disease. With improvements in organ preservation techniques, perioperative care, and immunosuppression, there is better patient and graft survival following LT, and assessment of the liver allograft in long-term survivors is becoming increasingly important. Recurrent or de novo viral or autoimmune injury remains the most common causes of chronic hepatitis and fibrosis following liver transplantation in adults. However, no obvious cause can be identified in many adults with controlled recurrent disease and the majority of pediatric LT recipients, as they have been transplanted for non-recurrent liver diseases. Serial surveillance liver biopsies post LT have been evaluated in several adult and pediatric centers to identify long-term pathological changes. Pathological findings are frequently present in liver biopsies obtained after a year post LT. The significance of these findings is uncertain as many of these are seen in protocol liver biopsies from patients with clinically good allograft function and normal liver chemistry parameters. This narrative review summaries the factors predisposing to long-term liver allograft fibrosis, highlighting the putative role of idiopathic post-LT hepatitis and chronic antibody mediated rejection in its pathogenesis.

COVID-19 and liver disease: mechanistic and clinical perspectives

Our understanding of the hepatic consequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and its resultant coronavirus disease 2019 (COVID-19) has evolved rapidly since the onset of the pandemic. In this Review, we discuss the hepatotropism of SARS-CoV-2, including the differential expression of viral receptors on liver cell types, and we describe the liver histology features present in patients with COVID-19. We also provide an overview of the pattern and relevance of abnormal liver biochemistry during COVID-19 and present the possible underlying direct and indirect mechanisms for liver injury. Furthermore, large international cohorts have been able to characterize the disease course of COVID-19 in patients with pre-existing chronic liver disease. Patients with cirrhosis have particularly high rates of hepatic decompensation and death following SARS-CoV-2 infection and we outline hypotheses to explain these findings, including the possible role of cirrhosis-associated immune dysfunction. This finding contrasts with outcome data in pharmacologically immunosuppressed patients after liver transplantation who seem to have comparatively better outcomes from COVID-19 than those with advanced liver disease. Finally, we discuss the approach to SARS-CoV-2 vaccination in patients with cirrhosis and after liver transplantation and predict how changes in social behaviours and clinical care pathways during the pandemic might lead to increased liver disease incidence and severity.

Outcomes following SARS-CoV-2 infection in liver transplant recipients: an international registry study

Background

Despite concerns that patients with liver transplants might be at increased risk of adverse outcomes from COVID-19 because of coexisting comorbidities and use of immunosuppressants, the effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on this patient group remains unclear. We aimed to assess the clinical outcomes in these patients.

Methods

In this multicentre cohort study, we collected data on patients with laboratory-confirmed SARS-CoV-2 infection, who were older than 18 years, who had previously received a liver transplant, and for whom data had been submitted by clinicians to one of two international registries (COVID-Hep and SECURE-Cirrhosis) at the end of the patient's disease course. Patients without a known hospitalisation status or mortality outcome were excluded. For comparison, data from a contemporaneous cohort of consecutive patients with SARS-CoV-2 infection who had not received a liver transplant were collected from the electronic patient records of the Oxford University Hospitals National Health Service Foundation Trust. We compared the cohorts with regard to several outcomes (including death, hospitalisation, intensive care unit [ICU] admission, requirement for intensive care, and need for invasive ventilation). A propensity score-matched analysis was done to test for an association between liver transplant and death.

Findings

Between March 25 and June 26, 2020, data were collected for 151 adult liver transplant recipients from 18 countries (median age 60 years [IQR 47–66], 102 [68%] men, 49 [32%] women) and 627 patients who had not undergone liver transplantation (median age 73 years [44–84], 329 [52%] men, 298 [48%] women). The groups did not differ with regard to the proportion of patients hospitalised (124 [82%] patients in the liver transplant cohort vs 474 [76%] in the comparison cohort, p=0·106), or who required intensive care (47 [31%] vs 185 [30%], p=0·837). However, ICU admission (43 [28%] vs 52 [8%], p<0·0001) and invasive ventilation (30 [20%] vs 32 [5%], p<0·0001) were more frequent in the liver transplant cohort. 28 (19%) patients in the liver transplant cohort died, compared with 167 (27%) in the comparison cohort (p=0·046). In the propensity score-matched analysis (adjusting for age, sex, creatinine concentration, obesity, hypertension, diabetes, and ethnicity), liver transplantation did not significantly increase the risk of death in patients with SARS-CoV-2 infection (absolute risk difference 1·4% [95% CI −7·7 to 10·4]). Multivariable logistic regression analysis showed that age (odds ratio 1·06 [95% CI 1·01 to 1·11] per 1 year increase), serum creatinine concentration (1·57 [1·05 to 2·36] per 1 mg/dL increase), and non-liver cancer (18·30 [1·96 to 170·75]) were associated with death among liver transplant recipients.

Interpretation

Liver transplantation was not independently associated with death, whereas increased age and presence of comorbidities were. Factors other than transplantation should be preferentially considered in relation to physical distancing and provision of medical care for patients with liver transplants during the COVID-19 pandemic.

Funding

European Association for the Study of the Liver, US National Institutes of Health, UK National Institute for Health Research.

Incidence of Recurrent NASH-Related Allograft Cirrhosis

BACKGROUND

Cirrhosis secondary to nonalcoholic steatohepatitis (NASH) is projected to become the leading indication for liver transplantation (LT) in the USA in the next decade. The long-term implications of post-LT NASH, specifically on the development of allograft cirrhosis, are not well known.

METHODS

A retrospective cohort of patients at a single large center undergoing LT for NASH from 2000 to 2015 was identified using a prospectively collected database. A total of 226 patients undergoing LT for NASH were identified. Mean follow-up for the cohort was 7 years. Seventy-five percent of patients underwent at least one liver biopsy post-LT.

RESULTS

Eighty-one patients (36%) developed recurrence of biopsy-proven NASH. Fifteen patients developed bridging fibrosis but only four patients (1.8%) progressed to recurrent NASH cirrhosis at a mean of 9 years post-LT. Body mass index at the time of LT was statistically higher in the NASH allograft cirrhosis group. Recurrent disease was less common and less severe in those transplanted with black donors. All four patients with recurrent NASH cirrhosis developed evidence of portal hypertension, but all remained alive at follow-up.

CONCLUSION

Although recurrent NASH following LT is common, the development of allograft cirrhosis is rare. These findings are useful when counseling patients and important to consider during their post-LT care.

Nonalcoholic steatohepatitis recurrence and rate of fibrosis progression following liver transplantation

BACKGROUND

Nonalcoholic steatohepatitis (NASH) is known to recur following liver transplantation (LT). Metabolic risk factors increase with immunosuppression. However, the rate of fibrosis progression following LT for NASH while on immunosuppression is less clear.

AIM

The incidences of steatosis, NASH, and fibrosis following LT for NASH were quantified and compared with those transplanted for alcoholic liver disease (ALD).

PATIENTS AND METHODS

Records of all NASH patients and 1 : 2 match with ALD transplant recipients between 2001 and 2006 were reviewed retrospectively. Patients without liver biopsies beyond 2 months following LT were excluded.

RESULTS

NASH patients (n=77) were older (P=0.0006) and less likely male (P<0.001) than ALD patients (n=108). The incidence of steatosis, NASH, and fibrosis stage increased at 1, 3, and 5 years in both groups. Although steatosis and nonalcoholic fatty liver disease activity scores were higher, fibrosis was lower in NASH compared with ALD (0.43 vs. 1.0 stage/year; P=0.0045). The incremental increase in the rate of fibrosis was faster in the first year compared with 4-5 years (0.8 vs. 0.04 stage/year) following LT. The rate of fibrosis progression during 4-5 years was decreased in NASH compared with ALD recipients (0.04 vs. 0.33 stage/year; P=0.015). NASH etiology was associated with reduced rate of fibrosis progression (odds ratio=0.67) on multivariate analysis.

CONCLUSION

Despite having more steatosis and inflammation, progression of fibrosis was slower in NASH compared with ALD recipients. Fibrosis progression slows with time following LT on immunosuppression and approximates the pretransplant progression rate by year 5.

De novo autoimmune hepatitis after liver transplantation: A focus on glutathione S-transferase theta 1

De novo autoimmune hepatitis (DAIH) is a rare clinical condition with features that resemble those of autoimmune hepatitis (AIH) in patients undergoing liver transplantation (LT) for nonautoimmune liver disease. The diagnosis of this entity has been based on the presence of biochemical and histological patterns similar to those observed in the primary AIH, although several considerations must be taken into account. The impact of DAIH on graft survival is relevant, and early diagnosis and treatment is associated with a good longterm outcome. Although glutathione S-transferase theta 1 (GSTT1) alloimmune recognition has been shown to be involved in the pathogenesis of DAIH, further studies are necessary to fully determine its pathogenic mechanisms and risk factors. We review the pathophysiology, the most common histological patterns, the treatment strategies, and the longterm outcomes of DAIH after LT with a special focus on GSTT1. Liver Transplantation 23:75-85 2017 AASLD.

Diagnosis, pathogenesis, and treatment of autoimmune hepatitis after liver transplantation

Autoimmune hepatitis can recur or appear de novo after liver transplantation, and it can result in hepatic fibrosis, graft loss, and re-transplantation. The goals of this review are to describe the prevalence, manifestations, putative pathogenic mechanisms, outcomes, and management of these occurrences. Autoimmune hepatitis recurs in 8-12 % of transplanted patients at 1 year and 36-68 % at 5 years. Recurrence may be asymptomatic and detected only by surveillance liver test abnormalities or protocol liver tissue examination. Autoantibodies that characterized the original disease, hypergammaglobulinemia, increased serum immunoglobulin G level, and histological findings of interface hepatitis, lymphoplasmacytic infiltration, perivenular hepatocyte necrosis, pseudo-rosetting, and acidophil bodies typify recurrence. Premature corticosteroid withdrawal and pre-transplant severity of the original disease are possible risk factors. De novo autoimmune hepatitis occurs in 1-7 % of patients 0.1-9 years after transplantation, especially in children. The appearance of autoantibodies may herald its emergence, and antibodies to glutathione-S-transferase T1 have been predictive of the disease. Recurrent disease may reflect recruitment of residual memory T lymphocytes and host-specific genetic predispositions, whereas de novo disease may reflect an allo-antigenic immune response and molecular mimicries that override self-tolerance. Treatment should be appropriate for autoimmune hepatitis and not based on anti-rejection drugs. Corticosteroid therapy alone or combined with azathioprine is the essential treatment. The substitution of mycophenolate mofetil for azathioprine and switch of the calcineurin inhibitor or its replacement with rapamycin have also been used for refractory disease. Re-transplantation has been necessary in 8-23 %.

What is the long-term outcome of the liver allograft?

With improved long-term survival following liver transplantation (LT), issues relating to the assessment of the liver allograft in long-term survivors are becoming increasingly relevant. Histological abnormalities are commonly present in late post-transplant biopsies, including protocol biopsies from patients who appear to be well with good graft function. Recurrent disease is the commonest recognised cause of abnormal graft histology, but may be modified by the effects of immunosuppression or interactions with other graft complications, resulting in complex or atypical changes. Other abnormalities seen in late post-transplant biopsies include rejection (which often has different appearances to those seen in the post-transplant period), de novo disease, "idiopathic" post-transplant hepatitis (IPTH) and nodular regenerative hyperplasia. In many cases graft dysfunction has more than one cause and liver biopsy may help to identify the predominant cause of graft damage. Problems exist with the terminology used to describe less well understood patterns of graft injury, but there is emerging evidence to suggest that late rejection, de novo autoimmune hepatitis and IPTH may all be part of an overlapping spectrum of immune-mediated injury occurring in the late post-transplant liver allograft. Careful clinico-pathological correlation is very important and the wording of the biopsy report should take into account therapeutic implications, particularly whether changes in immunosuppression may be indicated. This article will provide an overview of the main histological changes occurring in long-term survivors post-LT, focusing on areas where the assessment of late post-transplant biopsies is most relevant clinically.

Current views on rejection pathology in liver transplantation

Histological assessments continue to play an important role in the diagnosis and management of liver allograft rejection. The changes occurring in acute and chronic rejection are well recognized and liver biopsy remains the 'gold standard' for diagnosing these two conditions. Recent interest has focused on the diagnosis of late cellular rejection, which may have different histological appearances to early acute rejection and instead has features that overlap with so-called 'de novo autoimmune hepatitis' and 'idiopathic post-transplant chronic hepatitis'. There is increasing evidence to suggest that 'central perivenulitis' may be an important manifestation of late rejection, although other causes of centrilobular necro-inflammation need to be considered in the differential diagnosis. There are also important areas of overlap between rejection and recurrent hepatitis C infection and the distinction between these two conditions continues to be a problem in the assessment of liver allograft biopsies. Studies using immunohistochemical staining for C4d as a marker for antibody-mediated damage have found evidence of C4d deposition in liver allograft rejection, but the functional significance of these observations is currently uncertain. This review will focus on these difficult and controversial areas in the pathology of rejection, documenting what is currently known and identifying areas where further clarification is required.

Plasma cell hepatitis in hepatitis C virus patients post-liver transplantation: case-control study showing poor outcome and predictive features in the liver explant

Plasma cell hepatitis (PCH) is characterized by plasma cell infiltration seen in allografts of patients who underwent liver transplantation (LT) for conditions other than autoimmune hepatitis. We identified 40 PCH patients who underwent LT for hepatitis C virus (HCV) by searching our pathology database (1994-2006) for the keywords liver allograft, lymphoplasmacytic, and plasma cell(s). We selected 2 control patients who received LT for HCV for each PCH case. The control patients were matched according to date of LT and availability of biopsy material at the time interval to development of PCH in PCH patients. Explant and post-LT biopsy slides were blindly reviewed by 2 liver pathologists and the severity of the plasma cell infiltrate was scored. A score of 3 (plasma cells composing >30% of the infiltrate) defined PCH in allograft biopsies. Five random areas of dense inflammation were also examined in explant livers and the highest score was used. Poor outcome was defined as death or advanced fibrosis (stage >or= 4 of 6). We found that PCH patients were more likely to have worse outcomes than control patients (65% versus 40%, P < 0.01), including increased mortality (50% versus 30%, P < 0.05). Kaplan-Meier survival analysis showed significantly worse survival for PCH patients from 4 to 10 years post-LT (P < 0.05). Explants from 40% of PCH patients had a score of 3 compared to 18% of control patients (P < 0.01). We found that the development of PCH is associated with poor outcome in patients undergoing LT for HCV. The association of significant plasma cell infiltrates in native livers of HCV patients developing PCH suggests that some patients may have a predisposition to developing PCH.

Late protocol liver biopsies in the liver allograft: a neglected investigation?

As outcomes from liver transplantation have improved, attention has focused on long-term outcomes: patient and graft survival is affected by many factors, including the consequences of both overimmunosuppression (eg, renal failure and cancer) and underimmunosuppression (eg, rejection). The use of protocol (rather than event-driven) biopsies of the liver allograft, except for those grafted for HCV infection, has been largely abandoned. The aim of this study was to determine if protocol biopsies can improve the management of liver allograft recipients. A retrospective analysis of liver allograft recipients who had undergone protocol liver biopsies between 2000 and 2006 was performed. One hundred seventy-eight patients with normal liver tests (alcoholic liver disease, 49; autoimmune hepatitis, 20; and primary biliary cirrhosis, 107) who had undergone 235 protocol biopsies were identified. No significant complication from the biopsy was recorded. Liver histology was reported as normal or nearly normal in only 57 (24%). Chronic hepatitis (not obviously related to disease recurrence) was present in 78 (33%). Interpreted in the light of the calculated creatinine clearance, the biopsy findings indicated that overall immunosuppression (IMS) should be maintained or increased with standard calcineurin inhibitor (CNI)-based IMS in 25% of cases, that overall IMS should be reduced in 15% of cases, and that overall IMS should be maintained or increased by the substitution of non-nephrotoxic agents for CNIs in 9% of cases. The histological findings led to a documented change in IMS in 76 (32%) (increased IMS, 11; decreased IMS, 58; and switch from CNI, 7). In conclusion, protocol liver biopsy provides important histological information about graft function that is not available from standard liver tests and safely allows modification of IMS to ensure that long-term side effects of drug therapy (eg, renal failure) are minimized while graft function is sustained. Liver Transpl 15:931-938, 2009. (c) 2009 AASLD.

Chronic liver allograft dysfunction

Approximately 90% of liver transplant patients are alive after 1 year and 75% after 5 years with the majority leading full and near-normal lives. However, although early mortality rates after transplantation have fallen dramatically over the last 2 decades, the rates of late graft loss and patient death have remained constant. Thus, understanding of the causes of graft and patient failure is essential to improve long-term outcomes. In the early days after liver transplantation, ischemia and reperfusion injuries predominate, with acute cellular rejection relatively common in first 3 months. Thereafter, the causes of graft dysfunction are variable with disease recurrence as a major cause of graft loss. In this review, we discuss causes of graft dysfunction after 6 months.

A re-evaluation of the risk factors for the recurrence of primary sclerosing cholangitis in liver allografts

Previously, we have found that the absence of the colon after liver transplantation (LT) protects the patient from recurrent primary sclerosing cholangitis (rPSC). As our previous observation has not been confirmed in other series, we have reviewed our cohort of patients grafted for primary sclerosing cholangitis (PSC) with greater numbers and longer follow-up to reassess the rate, consequences, and risk factors for rPSC. We collected data on patients who underwent LT for PSC between January 1986 and April 2006. Data were collected for cytomegalovirus status, inflammatory bowel disease status, time of colectomy, type of colectomy, donor-recipient gender mismatch, recipient sex, extended donor criteria (EDC), and donor risk index. Accepted criteria were used to diagnose rPSC. Of a total of 230 consecutive adult patients, 61 (27%) underwent colectomy pre-/peri-LT, and 54 (23.5%) developed rPSC at a median of 4.6 (range, 0.5-12.9) years post-LT. A total of 263 deceased donor grafts were used, and 73 were EDC grafts. A diagnosis of rPSC was made in 61 of the 263 grafts (23%). The recurrence-free patient survival was significantly better (P < 0.05) in patients who underwent pre-/peri-LT colectomy and in those with non-EDC grafts. In conclusion, in this larger cohort of 230 patients and with longer follow-up of 82.5 (range, 0.0-238.6) months [in comparison with the previous report of 152 recipients with a follow-up of 52.8 (range, 1-146) months], we have shown that colectomy remains a significant risk factor for rPSC and that colectomy before and during initial LT for PSC confers a protective effect against rPSC in subsequent graft(s). Moreover, we have shown that EDC grafts are also a significant risk factor for rPSC.

Seeking beyond rejection: an update on the differential diagnosis and a practical approach to liver allograft biopsy interpretation

Pathologic evaluation of liver allograft biopsies plays an integral role in the management of patients after liver transplantation. This review summarizes the clinical context and classical histology of different types of allograft rejection and also the common entities that enter the differential diagnosis of allograft rejection, and provides practical approaches to liver allograft biopsy interpretation. In addition, some of the new developments in the field of liver transplant pathology are updated. The purpose of this review is to provide guidance for pathologists interpreting liver allograft biopsies, particularly those interested in developing expertise in the field of liver transplant pathology.

Autoimmune liver diseases and recurrence after orthotopic liver transplantation: what have we learned so far?

Primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH) may all recur after liver transplant. Diagnosis of rPBC is defined by histology; rAIH by serology, biochemistry and histology; rPSC by histology and/or imaging of the biliary tree and exclusion of other causes of nonanastomotic biliary strictures. Criteria for recurrent disease (RD) may differ from those used in similar disease in the native liver: frequent use of immunosuppressive therapy changes the pattern and natural history of RD and can co-exist with other transplant-related causes of graft damage. RD may occur in the presence of normal liver tests; the reported incidence will depend on the way in which diagnostic tests (especially protocol biopsies) are applied. The risk of RD increases with time, but does not correlate with the rate of graft loss. Treatment is largely unproven: ursodeoxycholic acid will improve serology and may slow progression of rPSC and rPBC; introduction or increased dose of corticosteroids may reduce progression of rAIH. Risk factors for rPBC include use of tacrolimus compared with cyclosporine; for rPSC include absence of colon peri-transplantation and for rAIH possible associations with some HLA haplotypes have been suggested.

Clinical features and management of autoimmune hepatitis

Autoimmune hepatitis (AIH) is a chronic hepatitis of unknown etiology which can progress to cirrhosis. Its clinical manifestations are highly variable and sometimes follow a fluctuating course. Diagnosis is based on characteristic histologic, clinical, biochemical and serological findings. Anti-inflammatory/immunosuppressive treatment frequently induces remission but long-term maintenance therapy is often required. Liver transplantation is generally successful in patients with decompensated cirrhosis unresponsive to or intolerant of medical therapy.

Hepatobiliary pathology

PURPOSE OF REVIEW

Studies are reviewed from the past year concerning the histopathology of liver and biliary diseases and their pathogenesis.

RECENT FINDINGS

Several cases of acute hepatitis E showed portal and periportal hepatitis, with polarization of neutrophils to the interface region and lymphocytes more centrally in the portal tracts. Transfection of hepatitis C virus into cultured fetal hepatocytes resulted in sustained growth of 50-90 nm diameter viral particles. The ductular reaction in nonalcoholic steatohepatitis appears to evolve with fibrosis in response to hepatocyte replicative senescence. Hepatocellular release of hepcidin is critical for iron homeostasis in a manner analogous to pancreatic insulin for glucose homeostasis; this 'endocrine' focus was elaborated in an overview of hemochromatosis. Specific microscopic features of liver-cell adenomas combined with genetic analysis for hepatocyte nuclear factor 1alpha and beta-catenin mutations allows differentiation into four variants. Steroid-sensitive biliary strictures resembling primary sclerosing cholangitis but with increased serum immunoglobulin G4 and infiltrating immunoglobulin G4-positive plasma cells ('immunoglobulin associated cholangitis') are part of a spectrum of disorders including autoimmune pancreatitis and inflammatory pseudotumor.

SUMMARY

Pathologic features of viral hepatitis C and E, immunohistochemistry for the ductular reaction and malignant liver tumors and several systemic disorders are among recent important pathology studies.