Are posttransplantation protocol liver biopsies useful in the long term?

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.

Value of posttransplant protocol biopsies in 2 biliary autoimmune liver diseases: A step toward personalized immunosuppressive treatment

The value of protocol liver graft biopsies with good liver function was evaluated in patients with primary sclerosing cholangitis (PSC) or primary biliary cholangitis (PBC).A total of 250 protocol liver biopsy reports from 182 PSC and PBC patients were compared. Overall histopathological findings and those leading to changes in immunosuppression therapy were retrospectively analyzed.The mean time to first protocol biopsy after transplantation was 5.5 (±4.5) years for PSC patients and 9.3 (±6.6) years for PBC patients. More than 1 abnormal histopathological parameter was found in 43% and 62% of PSC and PBC patients, respectively. However, the histology was interpreted as normal by the pathologist in 78% of PSC and 60% of PBC patients. Immunosuppression therapy was reduced in 10% and increased in 6% patients due to protocol biopsy findings. Biopsies leading to increased immunosuppression therapy had more portal (P = .004), endothelial (P = .008), interphase (P = .021), and lobular (P = .000) inflammation.Mild histopathological findings were frequently found in the protocol biopsies despite the normal biochemistry. PBC patients had more histological abnormalities than those transplanted due to PSC; however, PBC patients had longer follow-up times. Immunosuppression therapy could be safely increased or decreased according to protocol biopsy findings after multidisciplinary meeting discussions.

The real incidence of biliary tract complications after adult liver transplantation: the role of the prospective routine use of cholangiography during post-transplant follow-up

Biliary tract complications (BTCs) still burden liver transplantation (LT). The wide reporting variability highlights the absence of systematic screening. From 2000 to 2009, simultaneous liver biopsy and direct biliary visualization were prospectively performed in 242 recipients at 3 and 6 months (n = 212, 87.6%) or earlier when indicated (n = 30, 12.4%). Median follow-up was 148 (107-182) months. Seven patients (2.9%) experienced postprocedural morbidity. BTCs were initially diagnosed in 76 (31.4%) patients; 32 (42.1%) had neither clinical nor biological abnormalities. Acute cellular rejection (ACR) was present in 27 (11.2%) patients and in 6 (22.2%) BTC patients. Nine (3.7%) patients with normal initial cholangiography developed BTCs after 60 (30-135) months post-LT. BTCs directly lead to 7 (2.9%) re-transplantations and 14 (5.8%) deaths resulting in 18 (7.4%) allograft losses. Bile duct proliferation at 12-month biopsy proved an independent risk factor for graft loss (P = 0.005). Systematic biliary tract and allograft evaluation allows the incidence and extent of biliary lesions to be documented more precisely and to avoid erroneous treatment of ACR. The combination 'abnormal biliary tract-canalicular proliferation' is an indicator of worse graft outcome. BTCs are responsible for important delayed allograft and patient losses. These results underline the importance of life-long follow-up and appropriate timing for re-transplantation.

Donor-specific cell-free DNA as a biomarker in liver transplantation: A review

Due to advances in modern medicine, liver transplantation has revolutionised the prognosis of many previously incurable liver diseases. This progress has largely been due to advances in immunosuppressant therapy. However, despite the judicious use of immunosuppression, many liver transplant recipients still experience complications such as rejection, which necessitates diagnosis via invasive liver biopsy. There is a clear need for novel, minimally-invasive tests to optimise immunosuppression and improve patient outcomes. An emerging biomarker in this ''precision medicine'' liver transplantation field is that of donor-specific cell free DNA. In this review, we detail the background and methods of detecting this biomarker, examine its utility in liver transplantation and discuss future research directions that may be most impactful.

Acute cellular rejection in hepatitis C recipients following liver transplantation in the era of direct-acting antivirals: chronological analysis of the United Network for Organ Sharing database

INTRODUCTION

Interferon (IFN) treatment for liver transplant (LT) recipients with hepatitis C virus (HCV) increases acute cellular rejection (ACR) and worsens graft and patient survival. It is unknown if direct-acting antivirals (DAAs) affect rejection rates or post-transplant survival.

METHOD

The United Network for Organ Sharing STAR files of December 2017 (n = 25,916) were analyzed.

RESULTS

Compared with non-HCV-LT, HCV-LT survival was worse in the IFN-era (2007-2008) and IFN+DAA-era (2011), but not in the DAA-era (2014-2015). ACR6m rate has been less frequent in newer eras and was lower in HCV-LT than in non-HCV-LT in both the DAA-era (6.9% vs. 9.3%, P < 0.001) and in the IFN+DAA-era (8.8% vs. 11.8%, P = 0.001), but not in the IFN-era (10.8% vs. 11.0%, P = 0.39). HCV-LT recipients who had ACR6m had worse 2-year survival than those without ACR6m, in the IFN-era (80.0% vs. 88.4%, P < 0.0001) and in the IFN+DAA-era (81.4% vs. 89.2%, P < 0.01) but not in the DAA-era (90.4% vs. 93.2%, P = 0.085). Cox proportional hazard model identified ACR6m as independent risk factor for mortality in HCV-LT in the IFN-era (HR = 1.88, P ≤ 0.001) and in the IFN+DAA-era (HR = 1.84, P = 0.005), but not in the DAA-era (P = n.s.).

CONCLUSIONS

Two-year survival of HCV-LT recipients were significantly better in the DAA-era; these were associated with reduced rate and impact of ACR6m.

Use of direct-acting antiviral agents in hepatitis C virus-infected liver transplant candidates

Since the advent of direct acting antiviral (DAA) agents, chronic hepatitis C virus (HCV) treatment has evolved at a rapid pace. In contrast to prior regimen involving ribavirin and pegylated interferon, these newer agents are highly effective, well-tolerated, have shorter course of therapy and safer essentially in all HCV patients including those with advanced liver disease and following liver transplantation. Clinicians caring for HCV-infected patients on the liver transplant (LT) waitlist are often faced with a dilemma whether to treat HCV infection before or after liver transplantation. Sustained virological response (SVR) rates following HCV treatment may improve hepatic function sufficiently enough to negate the need for LT in certain patients. On the other hand, the decrease in MELD without improvement in quality of life in certain patients may lead to delay or dropout from potentially curative LT surgery list. In this context, our review focuses on the approach to and optimal timing of DAA-based treatment of HCV infection in LT candidates in the peri-transplant period.

Performance of transient elastography and serum fibrosis biomarkers for non-invasive evaluation of recurrent fibrosis after liver transplantation: A meta-analysis

Recurrent fibrosis after liver transplantation (LT) impacts on long-term graft and patient survival. We performed a meta-analysis to compare the accuracy of non-invasive methods to diagnose significant recurrent fibrosis (stage F2-F4) following LT. Studies comparing serum fibrosis biomarkers, namely AST-to-platelet ratio index (APRI), fibrosis score 4 (FIB-4), or transient elastography (TE) with liver biopsy in LT recipients were systematically identified through electronic databases. In the meta-analysis, we calculated the weighted pooled odds ratio and used a fixed effect model, as there was no significant heterogeneity between studies. Eight studies were included for APRI, four for FIB-4, and twelve for TE. The mean prevalence of significant liver fibrosis was 37.4%. The summary odds ratio was significantly higher for TE (21.17, 95% CI confidence interval 14.10–31.77, p = 1X10^-30) as compared to APRI (9.02, 95% CI 5.79–14.07; p = 1X10^-30) and FIB-4 (7.08, 95% CI 4.00–12.55; p = 1.93X10^-11). In conclusion, TE performs best to diagnose recurrent fibrosis in LT recipients. APRI and FIB-4 can be used as an estimate of significant fibrosis at centres where TE is not available. Longitudinal assessment of fibrosis by means of these non-invasive tests may reduce the need for liver biopsy.

Incidence and Predictors of Advanced Liver Fibrosis by a Validated Serum Biomarker in Liver Transplant Recipients

Background and Aims. Serum fibrosis biomarkers have shown good accuracy in the liver transplant (LT) population. We employed a simple serum biomarker to elucidate incidence and predictors of advanced fibrosis after LT over a long follow-up period. Methods. We included 440 consecutive patients who underwent LT between 1991 and 2013. Advanced liver fibrosis was defined as FIB-4 > 3.25 beyond 12 months after LT. Results. Over 2030.5 person-years (PY) of follow-up, 189 (43%) developed FIB-4 > 3.25, accounting for an incidence of 9.3/100 PY (95% confidence interval [CI], 8.1-10.7). Advanced fibrosis was predicted by chronic HCV infection (adjusted hazard ratio (aHR) = 3.96, 95% CI 2.92-5.36, p < 0.001), hypoalbuminemia (aHR = 2.31, 95% CI 1.72-3.09; p < 0.001), and hyponatremia (aHR = 1.48, 95% CI 1.09-2.01; p = 0.01). LT recipients with more than 1 predictor had a higher incidence of advanced fibrosis, the highest being when all 3 predictors coexisted (log-rank: p < 0.001). Conclusions. Chronic HCV infection, hypoalbuminemia, and hyponatremia predict progression to advanced liver fibrosis following LT. Patients with these risk factors should be serially monitored using noninvasive fibrosis biomarkers and prioritized for interventions.

Fibrosing cholestatic hepatitis C in post-transplant adult recipients of liver transplantation

Hepatitis C recurrence continues to present a major challenge in liver transplantation (LT). Approximately 10% of hepatitis C virus (HCV)-positive recipients will develop fibrosing cholestatic hepatitis (FCH) after LT. FCH is clinically characterized as marked jaundice with cholestatic hepatic dysfunction and high titers of viremia. Pathologically, FCH manifests as marked hepatocyte swelling, cholestasis, periportal peritrabecular fibrosis and only mild inflammation. This progressive form usually involves acute liver failure, and rapidly results in graft loss. A real-time and precise diagnosis based on histopathological examination and viral measurement is indispensable for the adequate treatment of FCH. Typical pathological findings of FCH are shown. Currently, carefully selected combinations of direct-acting antivirals (DAAs) offer the potential for highly effective and safe regimens for hepatitis C, both in the pre- and post-transplant settings. Here, we review FCH caused by HCV in LT recipients, and current strategies for sustained virological responses after LT. Only a few cases of successfully treated FCH C after LT by DAAs have been reported. The diagnostic findings and therapeutic dilemma are discussed based on a literature review.

Outcomes for patients with HCV after liver transplantation in Korea: a multicenter study

PURPOSE

HCV-related liver disease is the most common indication for liver transplantation (LT) in Western countries, whereas HCV LT is rare in Korea. We conducted a survey of HCV RNA-positive patients who underwent LT and investigated the prognostic factors for patient survival and the effects of immunosuppression.

METHODS

We retrospectively reviewed the multicenter records of 192 HCV RNA-positive patients who underwent LT.

RESULTS

The 1-, 3-, and 5-year overall survival rates were 78.8%, 75.3%, and 73.1%, respectively. Excluding the cases of hospital mortality (n = 23), 169 patients were evaluated for patient survival. Most patients were genotype 1 (n = 111, 65.7%) or genotype 2 (n = 42, 24.9%). The proportion of living donors for LT (n = 135, 79.9%) was higher than that of deceased donors (deceased donor liver transplantation [DDLT], n = 34, 20.1%). The median donor and recipient ages were 32 years and 56 years, respectively. Twenty-eight patients (16.6%) died during the observation period. Seventy-five patients underwent universal prophylaxis and 15 received preemptive therapy. HCV recurrence was detected in 97 patients. Recipients who were older than 60, received DDLT, used cyclosporine, or suffered acute rejection had lower rates of survival.

CONCLUSION

Patent survival rates of HCV patients after LT in Korea were comparable with other countries.

Serum fibrosis biomarkers predict death and graft loss in liver transplantation recipients

Noninvasive serum fibrosis biomarkers predict clinical outcomes in pretransplant patients with chronic liver disease. We investigated the role of serum fibrosis biomarkers and of changes in biomarkers in predicting death and graft loss after liver transplantation (LT). We included 547 patients who underwent LT between 1991 and 2012 and who met the following criteria: patient and graft survival > 12 months; serum fibrosis biomarkers aspartate aminotransferase-to-platelet ratio index (APRI), fibrosis score 4 (FIB-4), and nonalcoholic fatty liver disease (NAFLD) fibrosis score available at 1 year after LT; and a minimum follow-up of 1 year. Delta of fibrosis biomarkers was defined as (end of follow-up score--baseline score)/follow-up duration. Baseline and delta fibrosis biomarkers were associated with death: APRI > 1.5 (adjusted hazard ratio [aHR], 2.2; 95% confidence interval [CI], 1.4-3.3; P < 0.001) and delta APRI > 0.5 (aHR, 5.3; 95% CI, 3.4-8.2; P < 0.001); FIB-4 > 3.3 (aHR, 1.9; 95% CI, 1.3-2.8; P = 0.002) and delta FIB-4 > 1.4 (aHR, 2.4; 95% CI, 1.4-4.1; P = 0.001); and NAFLD fibrosis score > 0.7 (aHR, 1.9; 95% CI, 1.3-2.9; P = 0.002) and delta NAFLD fibrosis score (aHR, 3.7; 95% CI, 2.6-5.4; P < 0.001). Baseline and delta fibrosis biomarkers were associated also with graft loss. In conclusion, serum fibrosis biomarkers 1 year after LT and changes in serum fibrosis biomarkers predict death and graft loss in LT recipients. They may help in risk stratification of LT recipients and identify patients requiring closer monitoring.

Utility of liver biopsy in predicting clinical outcomes after percutaneous angioplasty for hepatic venous obstruction in liver transplant patients

AIM: To determine utility of transplant liver biopsy in evaluating efficacy of percutaneous transluminal angioplasty (PTA) for hepatic venous obstruction (HVOO).

METHODS: Adult liver transplant patients treated with PTA for HVOO (2003-2013) at a single institution were reviewed for pre/post-PTA imaging findings, manometry (gradient with right atrium), presence of HVOO on pre-PTA and post-PTA early and late biopsy (EB and LB, < or > 60 d after PTA), and clinical outcome, defined as good (no clinical issues, non-HVOO-related death) or poor (surgical correction, recurrent HVOO, or HVOO-related death).

RESULTS: Fifteen patients meeting inclusion criteria underwent 21 PTA, 658 ± 1293 d after transplant. In procedures with pre-PTA biopsy (n = 19), no difference was seen between pre-PTA gradient in 13/19 procedures with HVOO on biopsy and 6/19 procedures without HVOO (8 ± 2.4 mmHg vs 6.8 ± 4.3 mmHg; P = 0.35). Post-PTA, 10/21 livers had EB (29 ± 21 d) and 9/21 livers had LB (153 ± 81 d). On clinical follow-up (392 ± 773 d), HVOO on LB resulted in poor outcomes and absence of HVOO on LB resulted good outcomes. Patients with HVOO on EB (3/7 good, 4/7 poor) and no HVOO on EB (2/3 good, 1/3 poor) had mixed outcomes.

CONCLUSION: Negative liver biopsy greater than 60 d after PTA accurately identifies patients with good clinical outcomes.

Management of Hepatitis C Post-liver Transplantation: a Comprehensive Review

Infection with hepatitis C virus (HCV) is a common cause of chronic liver disease, and HCV-related cirrhosis and hepatocellular carcinoma are the leading causes for liver transplantation in the Western world. Recurrent infection of the transplanted liver allograft is universal in patients with detectable HCV viremia at the time of transplant and can cause a spectrum of disease, ranging from asymptomatic chronic infection to an aggressive fibrosing cholestatic hepatitis. Recurrent HCV is more aggressive in the post-transplant population and is a leading cause of allograft loss, morbidity, and mortality. Historically, treatment of recurrent HCV has been limited by low rates of treatment success and high side effect profiles. Over the past few years, promising new therapies have emerged for the treatment of HCV that have high rates of sustained virological response without the need for interferon based regimens. In addition to being highly effective, these treatments have higher rates of adherence and a lower side effect profile. The purpose of this review is to summarize current therapies in recurrent HCV infection, to review the recent advances in therapy, and to highlight areas of ongoing research.

Management of recurrent hepatitis C virus after liver transplantation

Chronic hepatitis C virus (HCV) infection is the leading cause of death from liver disease and the leading indication for liver transplantation (LT) in the United States and Western Europe. LT represents the best therapeutic alternative for patients with advanced chronic liver disease caused by HCV or those who develop hepatocarcinoma. Reinfection by HCV of the graft is universal and occurs in 95% of transplant patients. This reinfection can compromise graft function and patient survival. In a few cases, the histological recurrence is minimal and non-progressive; however, in most patients it follows a more rapid course than in immunocompetent persons, and frequently evolves into cirrhosis with graft loss. In fact, the five-year and ten-year survival of patients transplanted because of HCV are 75% and 68%, respectively, compared with 85% and 78% in patients transplanted for other reasons. There is also a pattern of recurrence that is very severe, but rare (< 10%), called fibrosing cholestatic hepatitis, which often involves rapid graft loss. Patients who present a negative HCV viremia after antiviral treatment have better survival. Many studies published over recent years have shown that antiviral treatment of post-transplant HCV hepatitis carried out during the late phase is the best option for improving the prognosis of these patients. Until 2011, PEGylated interferon plus ribavirin was the standard of care, resulting in a sustained virological response in around 30% of recipients. The addition of protease inhibitors, such as boceprevir or telaprevir, to the standard of care, or the use of other direct-acting antiviral drugs may involve therapeutic changes in the context of HCV recurrence. This may result a better prognosis for these patients, particularly those with severe recurrence or factors predicting rapid progression of fibrosis. However, the use of these agents in LT still requires clarification in terms of safety and efficacy.

Post-liver transplant hepatitis C virus recurrence: an unresolved thorny problem

Hepatitis C virus (HCV)-related cirrhosis represents the leading cause of liver transplantation in developed, Western and Eastern countries. Unfortunately, liver transplantation does not cure recipient HCV infection: reinfection universally occurs and disease progression is faster after liver transplant. In this review we focus on what happens throughout the peri-transplant phase and in the first 6-12 mo after transplantation: during this crucial period a completely new balance between HCV, liver graft, the recipient's immune response and anti-rejection therapy is achieved that will deeply affect subsequent outcomes. Nearly all patients show an early graft reinfection, with HCV viremia reaching and exceeding pre-transplant levels; in this setting, histological assessment is essential to differentiate recurrent hepatitis C from acute or chronic rejection; however, differentiating the two patterns remains difficult. The host immune response (mainly cellular mediated) appears to be crucial both in the control of HCV infection and in the genesis of rejection, and it is also strongly influenced by immunosuppressive treatment. At present no clear immunosuppressive strategy could be strongly recommended in HCV-positive recipients to prevent HCV recurrence, even immunotherapy appears to be ineffective. Nonetheless it seems reasonable that episodes of rejection and over-immunosuppression are more likely to enhance the risk of HCV recurrence through immunological mechanisms. Both complete prevention of rejection and optimization of immunosuppression should represent the main goals towards reducing the rate of graft HCV reinfection. In conclusion, post-transplant HCV recurrence remains an unresolved, thorny problem because many factors remain obscure and need to be better determined.

Recurrent hepatitis C after liver transplant

End stage liver disease from hepatitis C is the most common indication for liver transplantation in many parts of the world accounting for up to 40% of liver transplants. Antiviral therapy either before or after liver transplantation is challenging due to side effects and lower efficacy in patients with cirrhosis and liver transplant recipients, as well as from drug interactions with immunosuppressants. Factors that may affect recurrent hepatitis C include donor age, immunosuppression, IL28B genotype, cytomegalovirus infection, and metabolic syndrome. Older donor age has persistently been shown to have the greatest impact on recurrent hepatitis C. After liver transplantation, distinguishing recurrent hepatitis C from acute cellular rejection may be difficult, although the development of molecular markers may help in making the correct diagnosis. The advent of interferon free regimens with direct acting antiviral agents that include NS3/4A protease inhibitors, NS5B polymerase inhibitors and NS5A inhibitors holds great promise in improving outcomes for liver transplant candidates and recipients.

Hepatitis C recurrence: the Achilles heel of liver transplantation

Hepatitis C virus (HCV) infection is the most common indication for liver transplantation worldwide; however, recurrence post transplant is almost universal and follows an accelerated course. Around 30% of patients develop aggressive HCV recurrence, leading to rapid fibrosis progression (RFP) and culminating in liver failure and either death or retransplantation. Despite many advances in our knowledge of clinical risks for HCV RFP, we are still unable to accurately predict those most at risk of adverse outcomes, and no clear consensus exists on the best approach to management. This review presents a critical overview of clinical factors shown to influence the course of HCV recurrence post transplant, with particular focus on recent data identifying the important role of metabolic factors, such as insulin resistance, in HCV recurrence. Emerging data for genetic markers of HCV recurrence and their usefulness for predicting adverse outcomes will also be explored.

MicroRNAs in Liver Disease: Bench to Bedside

MicroRNAs (miRs) are small non-coding RNAs that negatively regulate gene expression by pairing with partially complementary target sequences in the 3'UTRs of mRNAs to promote degradation and/or block translation. Aberrant miR expression is associated with development of multiple diseases including hepatic diseases. The role of miRs in the regulation of gene expression and rapid progress in the field of microRNA research are resulting in momentum toward development of diagnostic markers and novel therapeutic strategies for human liver diseases. Recent studies provide clear evidence that miRs are abundant in the liver and modulate a diverse spectrum of biological functions, thereby supporting an association between alterations of miR homeostasis and pathological liver diseases. Here we review the role of miRs in liver as their physiological and pathological importance has been demonstrated in metabolism, immunity, viral hepatitis, oncogenesis, fatty liver diseases (alcoholic and non-alcoholic), drug-induced liver injury, fibrosis as well as acute liver failure.

The meaning of tissue and serum HCV RNA quantitation in hepatitis C recurrence after liver transplantation: a retrospective study

BACKGROUND

While the role of serum HCV RNA quantitation in hepatitis C virus recurrence after liver transplantation is well established, the meaning of HCV RNA tissue quantitation is largely unclear, and no correlations with recipient outcome have been investigated yet.

AIMS

To assess the predictive value, and a possible prognostic role, of tissue and serum HCV RNA in first post-transplant biopsies.

METHODS

We retrospectively reviewed the first post-transplant biopsies of 83 recipients. Tissue and serum HCV RNA was quantitated by RT-PCR, and compared with serum, clinical and histological data.

RESULTS

HCV RNA quantitation allowed us to categorise recipients into three different risk groups: (1) tissue HCV RNA ≤ 1.5 IU/ng with any serum HCV RNA; (2) tissue HCV RNA>1.5 IU/ng and serum HCV RNA < 40 × 10(6)copies/mL; (3) tissue HCV RNA>1.5 IU/ng and serum HCV RNA ≥ 40 × 10(6)copies/mL. Hepatitis C virus recurrence rates in the three groups were 68%, 91% and 100% (P=0.004); hepatitis C virus-related mortality was 0%, 14% and 45% respectively (P<0.001).

CONCLUSIONS

This preliminary study on serum and tissue HCV RNA quantitation allows recipient "stratification" in prognostic groups, which could be applicable in the future for timely antiviral treatment and/or immunosuppression modulation.

Liver Transplant Pathology: Review of Challenging Diagnostic Situations

Histopathologic assessment of allograft liver biopsies has an important role in managing patients who have undergone liver transplantation. In this review, several topics are discussed that create diagnostic problems in transplant pathology, with emphasis on pathologic features and differential diagnosis. The topics discussed are acute cellular rejection, late acute rejection (centrizonal/parenchymal rejection), chronic rejection, plasma cell hepatitis, idiopathic posttransplant chronic hepatitis, fibrosing cholestatic hepatitis, selected viral infections (cytomegalovirus, Epstein-Barr virus, and hepatitis E), and acute antibody-mediated rejection.

MicroRNA signature at the time of clinical HCV recurrence associates with aggressive fibrosis progression post-liver transplantation

Diagnosis and prediction of the severity of hepatitis C virus recurrence (HCVrec) after liver transplantation (LT) remain a challenge. MicroRNAs have been recently recognized as potential disease biomarkers. Archival liver biopsy samples from 43 HCV+ LT recipients were collected at clinical HCVrec time and at 3 years post-LT. Patients were classified as progressors (P = F0/F1) or nonprogressors (NP = F3/F4) according to the severity of fibrosis on the 3-year biopsy. Training (n = 27) and validation (n = 16) sets were defined. RNA was isolated from all biopsies at clinical HCVrec time, labeled and hybridized to miRNA-arrays. Progressors versus nonprogressors were compared using the two-sample t-test. A p-value ≤0.01 was considered significant. The ingenuity pathway analysis tool was used for microRNA and miRNA:mRNA ontology data integration. Nine microRNAs were differentially expressed between groups. A supervised cluster analysis separated samples in two well-defined groups (progressors vs. nonprogressors). Pathway analysis associated those microRNAs with hepatitis, steatosis, fibrosis, cirrhosis and T cell-related immune response. Data integration identified 17 genes from a previous genomic study as 9-microRNAs signature targets. Seven microRNAs were successfully validated in the validation set using QPCR. We have identified a 9-microRNA signature able to identify early post-LT patients at high risk of severe HCVrec during long-term follow-up.

Low-dose steroids associated with milder histological changes after pediatric liver transplantation

Controversy remains about the role of protocol liver biopsy for symptom-free recipients and about the long-term use of low-dose steroids after pediatric liver transplantation (LT). We conducted a national cross-sectional study of pediatric recipients who underwent LT between 1987 and 2007. Liver biopsy samples were taken from 54 patients (82% of survivors) after a median posttransplant follow-up of 11 years, and they were reviewed by 2 pathologists blinded to the clinical data. Biopsy samples from 18 patients (33%) showed nearly normal histology with no inflammation, fibrosis, or steatosis. Portal inflammation was detected in 14 samples (26%), showed no correlation with anti-nuclear antibodies, and was less frequent in the 35 patients whose immunosuppression included steroids (14% versus 47% of patients not using steroids, P = 0.008). Fibrosis was present in 21 biopsy samples (39%). According to the Metavir classification, 16 were stage 1, 3 were stage 2, and 2 were stage 3. The fibrosis stage correlated negatively with serum prealbumin levels (r = -0.364, P = 0.007) and positively with chronic cholestasis (cytokeratin 7 staining; r = 0.529, P < 0.001) and portal inflammation (r = 0.350, P = 0.01). Microvesicular steatosis was found in 23 biopsy samples (43% of patients in 5%-80% of hepatocytes), and it correlated with the body mass index (r = 0.458, P < 0.001) but not with steroid use. The age of the allograft (donor age plus follow-up time) correlated with higher serum gamma-glutamyltransferase (r = 0.472, P < 0.001) and conjugated bilirubin levels (r = 0.420, P = 0.002) as well as chronic cholestasis (r = 0.299, P = 0.03). The biopsy findings led to treatment changes in 10 patients (19%), whereas only 1 complication (subcapsular hematoma) was encountered. In conclusion, continuing low-dose steroids indefinitely after pediatric LT may have a positive effect on the long-term histological state of the liver graft. Allograft aging may lead to chronic cholestasis and thus contribute to the development of liver fibrosis.

Importance of liver biopsy findings in immunosuppression management: biopsy monitoring and working criteria for patients with operational tolerance

Obstacles to morbidity-free long-term survival after liver transplantation (LT) include complications of immunosuppression (IS), recurrence of the original disease and malignancies, and unexplained chronic hepatitis and graft fibrosis. Many programs attempt to minimize chronic exposure to IS by reducing dosages and stopping steroids. A few programs have successfully weaned a highly select group of recipients from all IS without apparent adverse consequences, but long-term follow-up is limited. Patients subjected to adjustments in IS are usually followed by serial liver chemistry tests, which are relatively insensitive methods for detecting allograft damage. Protocol biopsy has largely been abandoned for hepatitis C virus-negative recipients, at least in part because of the inability to integrate routine histopathological findings into a rational clinical management algorithm. Recognizing a need to more precisely categorize and determine the clinical significance of findings in long-term biopsy samples, the Banff Working Group on Liver Allograft Pathology has reviewed the literature, pooled the experience of its members, and proposed working definitions for biopsy changes that (1) are conducive to lowering IS and are compatible with operational tolerance (OT) and (2) raise concern for closer follow-up and perhaps increased IS during or after IS weaning. The establishment of guidelines should help us to standardize analyses of the effects of various treatments and/or weaning protocols and more rigorously categorize patients who are assumed to show OT. Long-term follow-up using standardized criteria will help us to determine the consequences of lowering IS and to define and determine the incidence and robustness of OT in liver allografts.

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 %.

[Histological lesions in the graft in patients with long-term survival after transplantation. Are protocol biopsies necessary?]

The main lesions found in long-term liver grafts are recurrence of underlying liver disease and the development of de novo diseases or heterogeneous lesions of unknown etiology. In a not insignificant percentage of patients, the results of laboratory tests are normal and these lesions are only detected by liver biopsy. Diagnosis of these lesions is essential since they can affect patient and graft prognosis and may require changes in immunosuppressive therapy or the introduction of new drugs to treat specific diseases. Moreover, some patients with normally functioning liver grafts could benefit from minimization of immunosuppressive therapy. Currently, the performance of protocol biopsies cannot be recommended. However, given the high prevalence of these lesions, grafts should be closely monitored. Transient elastrography could play a role in the selection of patients who might benefit from a liver biopsy.

Transient elastography identifies liver recipients with nonviral graft disease after transplantation: a guide for liver biopsy

Transient elastography (TE) reliably predicts the severity of recurrent hepatitis C virus after orthotopic liver transplantation (OLT); however, its accuracy in evaluating nonviral liver graft damage is unknown. Between 2006 and 2009, 69 OLT recipients [37 for hepatitis B virus/hepatitis D virus (recurrence-free), 20 for autoimmune/cholestatic liver disease, 6 for alcoholic liver disease, and 6 for mixed etiologies] underwent protocol/on-demand liver biopsy (LB) and concomitant TE. A histological diagnosis of graft disease was made according to criteria defined by the Banff working group. Sixty-five patients (94%) had reliable TE examinations during a median post-OLT follow-up of 18 months (range = 7-251 months). LB samples (median length = 35 mm) showed graft damage in 28 patients (43%): idiopathic chronic hepatitis (11), steatohepatitis (3), rejection (3), cholangitis (2), and autoimmune/cholestatic recurrence (9). Patients with graft damage had significantly higher serum liver enzyme levels and TE results (median = 7.8 kPa, range = 5.4-27.4 kPa) than the 37 patients without graft damage (median = 5.3 kPa, range = 3.1-7.4 kPa, P < 0.001). By a receiver operating characteristic curve analysis, 2 TE cutoffs for the diagnosis of graft damage were identified: 5.3 kPa with 100% sensitivity and 7.4 kPa with 100% specificity. The pretest probability of graft damage was 43%; in patients with TE values ≤5.3 kPa, the posttest probability of graft damage fell to 0%, but in patients with TE results >7.4 kPa, the posttest probability increased to 100%. In conclusion, the dual TE cutoff allows accurate discrimination between the absence and presence of nonviral liver graft damage and improves the clinical management of OLT recipients in terms of the selection of patients most in need of LB.

Spanish society of liver transplantation (SETH) consensus recommendations on hepatitis C virus and liver transplantation

In November 2010, the Spanish Society of Liver Transplantation (Sociedad Española de Trasplante Hepático, SETH) held a consensus conference. One of the topics of debate was liver transplantation in patients with hepatitis C. This document reviews (i) the natural history of post-transplant hepatitis C, (ii) factors associated with post-transplant prognosis in patients with hepatitis C, (iii) the role of immunosuppression in the evolution of recurrent hepatitis C and response to antiviral therapy, (iv) antiviral therapy, both before and after transplantation, (v) follow-up of patients with recurrent hepatitis C and (vi) the role of retransplantation.

Liver transplantation and hepatitis C

Hepatitis-C-virus- (HCV-) related end-stage cirrhosis is the primary indication for liver transplantation in many countries. Unfortunately, however, HCV is not eliminated by transplantation and graft reinfection is universal, resulting in fibrosis, cirrhosis, and finally graft decompensation. The use of poor quality organs, particularly from older donors, has a highly negative impact on the severity of recurrence and patient/graft survival. Although immunosuppressive regimens have a considerable impact on the outcome, the optimal regimen after liver transplantation for HCV-infected patients remains unclear. Disease progression monitoring with protocol biopsy and new noninvasive methods is essential for predicting patient/graft outcome and starting antiviral treatment with the appropriate timing. Antiviral treatment with pegylated interferon and ribavirin is currently considered the most promising regimen with a sustained viral response rate of around 30% to 35%, although the survival benefit of this regimen remains to be investigated. Living-donor liver transplantation is now widely accepted as an established treatment for HCV cirrhosis and the results are equivalent to those of deceased donor liver transplantation.

Hepatobiliary transporter expression and post-operative jaundice in patients undergoing partial hepatectomy

BACKGROUND AND AIMS

Post-operative hyperbilirubinaemia in patients undergoing liver resections is associated with high morbidity and mortality. Apart from different known factors responsible for the development of post-operative jaundice, little is known about the role of hepatobiliary transport systems in the pathogenesis of post-operative jaundice in humans after liver resection.

METHODS

Two liver tissue samples were taken from 14 patients undergoing liver resection before and after Pringle manoeuvre. Patients were retrospectively divided into two groups according to post-operative bilirubin serum levels. The two groups were analysed comparing the results of hepatobiliary transporter [Na-taurocholate cotransporter (NTCP); multidrug resistance gene/phospholipid export pump(MDR3); bile salt export pump (BSEP); canalicular bile salt export pump (MRP2)], heat shock protein 70 (HSP70) expression as well as the results of routinely taken post-operative liver chemistry tests.

RESULTS

Patients with low post-operative bilirubin had lower levels of NTCP, MDR3 and BSEP mRNA compared to those with high bilirubin after Pringle manoeuvre. HSP70 levels were significantly higher after ischaemia-reperfusion (IR) injury in both groups resulting in 4.5-fold median increase. Baseline median mRNA expression of all four transporters prior to Pringle manoeuvre tended to be lower in the low bilirubin group whereas expression of HSP70 was higher in the low bilirubin group compared to the high bilirubin group.

DISCUSSION

Higher mRNA levels of HSP70 in the low bilirubin group could indicate a possible protective effect of high HSP70 levels against IR injury. Although the exact role of hepatobiliary transport systems in the development of post-operative hyper bilirubinemia is not yet completely understood, this study provides new insights into the molecular aspects of post-operative jaundice after liver surgery.

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.

Hepatitis C virus recurrence after liver transplantation: biomarkers of disease and fibrosis progression

End-stage liver disease due to hepatitis C virus infection (HCV) is the principal indication for liver transplantation. In the USA, over a third of available liver allografts are transplanted into recipients with chronic HCV infection. Reinfection of the graft is universal, but the impact of reinfection on short- and long-term liver function is highly variable. HCV infection in liver transplantation recipients is characterized by an accelerated fibrogenesis, with approximately a third of patients developing cirrhosis within 5 years of follow-up. HCV is associated with decreased patient and graft survival when compared with other indications of orthotopic liver transplantation. The mechanisms responsible for the accelerated liver damage in HCV-infected orthotopic liver transplantation recipients remain largely unknown.

Prospective validation of a noninvasive index for predicting liver fibrosis in hepatitis C virus-infected liver transplant recipients

We previously developed a mathematical model, the Hospital Universitario La Fe (HULF) index, as an alternative to protocol liver biopsy (PLB) to estimate significant fibrosis (SF) in patients who underwent liver transplantation (LT) for liver damage caused by chronic HCV infection. In the present study, we sought to validate this noninvasive index. The commonly derived clinical and laboratory data for calculating the HULF index were prospectively collected over 2.7 years from patients undergoing LT and PLB. The sensitivity, specificity, positive and negative predictive values, and diagnostic capacity were evaluated with receiver operating characteristic curve analysis. Biopsy was performed 93 times in 86 LT patients. The prevalence of SF (F3-F4 on the Knodell scoring system) was 32%. The intraobserver and interobserver concordance was high (kappa = 0.94 and kappa = 0.75, respectively) in identifying SF in PLB. For low scores, the HULF index discarded an SF diagnosis with a sensitivity of 90% and a negative predictive value of 89%. The area under the receiver operating characteristic curve was 0.68. The precision of the HULF index did not improve with the incorporation of donor age and body mass index into the multivariate analysis. Applying the index would have prevented 24% of the biopsy procedures performed. In conclusion, the HULF index was prospectively validated with data commonly obtained in standard clinical practice. Because the index distinguishes a subgroup of HCV LT patients with a low probability of having SF, PLB would be avoided in those patients.

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.

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.

Outcomes of 5-year survivors of pediatric liver transplantation: report on 461 children from a north american multicenter registry

OBJECTIVES

Although liver transplantation has been the standard of care therapy for life-threatening liver diseases for >20 years, data on the long-term impact of liver transplantation in children have been primarily limited to single-center experiences. The objective of this study was to characterize and evaluate the clinical course of children who have survived >or=5 years after pediatric liver transplantation in multiple centers across North America.

PATIENTS AND METHODS

Patients enrolled in the Studies of Pediatric Liver Transplantation database registry who had undergone liver transplantation at 1 of 45 pediatric centers between 1996 and 2001 and survived >5 years from liver transplantation were identified and their clinical courses retrospectively reviewed.

RESULTS

The first graft survival for 461 five-year survivors was 88%, with 55 (12%) and 10 (2%) children undergoing a second and third liver transplantation. At the 5-year anniversary clinic visit, liver function was preserved in the majority with daily use of immunosuppression therapy, including a calcineurin inhibitor and oral prednisone, reported by 97% and 25% of children, respectively. The probability of an episode of acute cellular rejection occurring within 5 years after liver transplantation was 60%. Chronic rejection occurred in 5% patients. Posttransplant lymphoproliferative disease was diagnosed in 6% children. Calculated glomerular filtration rate was <90 mL/minute per 1.73 m2 in 13% of 5-year survivors. Age- and gender-adjusted BMI>95th percentile was noted in 12%, with height below the 10th percentile in 29%.

CONCLUSIONS

Children who are 5-year survivors of liver transplantation have good graft function, but chronic medical conditions and posttransplantation complications affect extrahepatic organs. A comprehensive approach to the management of these patients' multiple unique needs requires the expertise and commitment of health care providers both beyond and within transplant centers to further optimize long-term outcomes for pediatric liver transplant recipients.

Impact of immunosuppression without steroids on rejection and hepatitis C virus evolution after liver transplantation: results of a prospective randomized study

The purpose of this study was to evaluate the influence of a steroid-free immunosuppression on hepatitis C virus (HCV) recurrence. A total of 198 liver transplantation (LT) patients were randomized to receive immunosuppression with basiliximab and cyclosporine, either with prednisone (steroid [St] group) or without prednisone (no steroids [NoSt] group). The group of 89 HCV-infected patients was followed up with protocol biopsies for 2 years after LT. This group of HCV patients are the patients evaluated in the present study. The rejection rate was 19% (St: 21% versus NoSt: 17%; P = 0.67). Patients in the St group had a slightly higher rate of bacterial infections (59% versus 38%; P = 0.05). Almost all patients had histological HCV-recurrence (St: 39/40 (97%) versus NoSt: 40/41 (97%); P = 1). The percentage of accumulated biopsies with grade 4 portal inflammation at 6 months, 1 year, and 2 years were, 23%, 49%, and 49% in the NoSt group, compared to 33%, 55%, and 69% in the St group, respectively (P = 0.04 at 2 years). The percentage of accumulated biopsies with grade 3 or 4 fibrosis at 6 months, 1 year, and 2 years were 0%, 8%, and 22% in the NoSt group, compared to 8%, 19%, and 31% in the St group, respectively. Immunosuppression without steroids in HCV patients is safe, reduces bacterial infections and metabolic complications, and improves histological short-term evolution of HCV recurrence.

The natural history of recurrent hepatitis C and what influences this

1. Liver failure and liver cancer from chronic hepatitis C are the most common indications for liver transplantation and numbers of both are projected to double over the next 20 years. 2. Recurrent hepatitis C infection of the allograft is universal and immediate following liver transplantation and associated with accelerated progression to cirrhosis, graft loss and death. 3. Graft and patient survival is reduced in liver transplant recipients with recurrent HCV infection compared to HCV-negative recipients. 4. The natural history of chronic hepatitis C is accelerated following liver transplantation compared C, with 20% progressing to cirrhosis by 5 years. However, the rate of fibrosis progression is not uniform and may increase over time. 5. The rates of progression from cirrhosis to decompensation and from decompensation to death are also accelerated following liver transplantation. 6. Multiple host, donor and viral factors are associated with rapid fibrosis progression and HCV-related graft failure. 7. Over the last decade, graft and patient survival rates have improved following liver transplantation for non-HCV disease but not for HCV-cirrhosis. This may reflect worsening donor quality and changes in immunosuppression strategies over recent years. 8. Viral eradication by antiviral therapy prevents disease progression and improves survival. 9. The severity of recurrent hepatitis C at one year post-transplant predicts subsequent progression to cirrhosis. Annual protocol biopsies are recommended to help determine need for antiviral therapy. 10. The projected impact of recurrent hepatitis C on graft and patient survival can only be avoided by the development of safe and effective antiviral strategies which can both prevent initial graft infection and eradicate established hepatitis C recurrence.

Monitoring of human liver and kidney allograft tolerance: a tissue/histopathology perspective

Several factors acting together have recently enabled clinicians to seriously consider whether chronic immunosuppression is needed in all solid organ allograft recipients. This has prompted a dozen or so centers throughout the world to prospectively wean immunosuppression from conventionally treated liver allograft recipients. The goal is to lessen the impact of chronic immunosuppression and empirically identify occasional recipients who show operational tolerance, defined as gross phenotype of tolerance in the presence of an immune response and/or immune deficit that has little or no significant clinical impact. Rare operationally tolerant kidney allograft recipients have also been identified, usually by single case reports, but only a couple of prospective weaning trials in conventionally treated kidney allograft recipients have been attempted and reported. Pre- and postweaning allograft biopsy monitoring of recipients adds a critical dimension to these trials, not only for patient safety but also for determining whether events in the allografts can contribute to a mechanistic understanding of allograft acceptance. The following is based on a literature review and personal experience regarding the practical and scientific aspects of biopsy monitoring of potential or actual operationally tolerant human liver and kidney allograft recipients where the goal, intended or attained, was complete withdrawal of immunosuppression.

Protocol liver allograft biopsies

Protocol liver allograft biopsies are liver biopsies carried out at specific time points according to predetermined guidelines, rather than in response to specific indications such as change in the patient's clinical status or biochemical tests. Use of protocol liver allograft biopsy has been declining over the last decade: an informal survey of 35 transplant units showed that whereas 65% of units undertake protocol biopsies for those grafted for Hepatitis C virus infection, only 25% do so for patients grafted for other indications. In this overview, we consider the arguments against and those in favor of liver biopsies in adult liver allograft recipients. Arguments against the use of protocol liver biopsies are that they biopsies put the patient are associated with a small risk of morbidity and mortality, are expensive, do not provide useful information and do not alter clinical practice. The estimated rate of major complications is 0.6% and the estimated mortality rate 0.02%. However, the argument in favor of protocol biopsies is that even when standard liver tests are normal, there is on-going inflammation in the graft which, if immunosuppression is not altered, will lead to progressive fibrosis, cirrhosis and even graft loss. Conversely, normal liver histology may allow for reduction in the immunosuppression and so lower the risk of the complications associated with immunosuppression. Currently available diagnostic techniques are not yet sufficiently sensitive or specific to provide an accurate reflection of the state of the graft and the presence or absence of graft damage. We conclude that, while there are no clear data showing that protocol liver allograft biopsies are cost effective and lead to improved patient and graft outcome, such biopsies still have a role in the management of the liver transplant recipient.

Histologic abnormalities are common in protocol liver allograft biopsies from patients with normal liver function tests

The utility of protocol liver allograft biopsies remains controversial, particularly in patients with normal liver function tests (LFTs). However, histologic evaluation of these biopsies provides an opportunity to examine the types and severity of liver diseases that can occur in livers with normal clinical and biochemical function. We studied 165 protocol allograft biopsies taken from 100 liver transplant patients at the time of normal LFTs and normal clinical function at 3 to 8 months (n=36), 1 year (n=52), 2 to 3 years (n=54), and 4 to 5 years (n=23). Biopsies were classified as normal, minimal changes (eg, nonaggressive portal or lobular mononuclear inflammation, steatosis <10%), fatty liver disease, recurrent primary liver disease, and transplant-related disease (portal-based rejection or central venulitis, an inflammatory pattern that encompasses perivenular hepatocyte dropout, mononuclear inflammation, pigment-laden macrophages, and variable zone 3 fibrosis). Among these 100 patients, a total of 394 protocol biopsies were performed, and 165 (42%) were taken at the time of normal LFTs and normal clinical function. One hundred twenty-one (73%) were normal or showed minimal/nonspecific changes. Forty-four (27%) showed histologic abnormalities that included fatty liver disease (n=19, nonalcoholic in 18 cases; 13 with mild steatosis, 6 with moderate steatosis, 7 with grade 1/3 steatohepatitic activity, and 2 with stage 1/4 steatohepatitic fibrosis), recurrent primary biliary cirrhosis (n=9; all stage 1/4), recurrent hepatitis C infection (n=6; grade 0/4 in 1, grade 1/4 in 5, stage 0/4 in 4, stage 1/4 in 1, and stage 2/4 in 1), recurrent sarcoidosis (n=1), Ito cell hyperplasia (n=4; marked in 2 and mild in 2), central venulitis (n=10; 5 with mild zone 3 fibrosis or central vein obliteration and 1 with central-portal bridging fibrosis), and mild acute portal rejection (n=2). We judged the histologic changes to be of clinical significance in 19 (11.5%) cases. These results indicate that even at the time of normal clinical and laboratory function, a significant fraction of protocol allograft biopsies harbor histologic (27%) and clinically significant (11.5%) abnormalities. These most commonly include fatty liver disease, low-grade/low-stage recurrent hepatitis C and primary biliary cirrhosis, and central venulitis (including some cases with subsequent fibrosis progression). The data support performance of protocol biopsies to assess allograft status, and provide insight into the types and severity of liver diseases that can smolder in transplanted (and by extension, probably also in native) livers with apparent normal function.

[Treatment of recurrent hepatitis C virus infection after liver transplantation]

The main indication of liver transplantation is the final stage of liver cirrhosis developed in hepatitis C virus (HCV) infection. The recurrence of HCV infection after transplantation is a common situation. The recurrent hepatitis C is a progressive disease, in 20 percent of patients it produces liver cirrhosis without treatment beside immunosuppression within 5 years. The treatment of recurrent HCV infection is the most important factor of the survival in patients with transplantation. The authors review the factors influencing the progression of recurrent HCV infection on the basis of literary data and also on their observation. They discuss in details the effect of immunosuppressive treatment, the importance in the selection of corresponding immunosuppressive drugs. They review the main keypoints in the diagnosis of recurrent hepatitis C, underline the important role of liver biopsy carried out according to the protocol in the diagnosis, furthermore the hard consultation among pathologist, hepatologist and surgeon. They demonstrate the observations with the treatment of patients on the waiting list, the results in the early, preemptive treatment of recurrent chronic hepatitis, furthermore the treatment modalities and the results in patients with chronic hepatitis C histologically proved. The drug of choice of chronic hepatitis C after transplantation is the combined therapy with pegylated interferon and ribavirin. This therapy is able to assure virus-free stage in 20-50 percent of patients. In the virus-free patients the inflammatory activity in the liver significantly decreases, the histologic activity index improves. There are data showing the effect of treatment for inhibiting the fibrosis, but multicenter studies are necessary for the confirmation of these data. The advantage of early antiviral therapy without histologic alteration has not been confirmed by most of the trials. The anaemia and the neutropenia are frequent side effects in this patient group, that is why the applications of erythropoietin and granulocyte stimulating factor are recommended. Further trials and clinical studies are necessary for the optimal treatment of patients with recurrent hepatitis C, and to determine the dosage of pegylated interferon and ribavirin, to decrease the duration of therapy and the side effects, finally to achieve a healing phase of higher degree.

Viral hepatitis after liver transplantation

Recurrence of the original liver disease following liver transplantation is a typical complication in viral hepatitis. Recent advances, particularly the development of strategies to prevent or effectively treat hepatitis B, have led to substantial improvements in the post-transplantation outcome of hepatitis B candidates. While the efficacy of antivirals to treatrecurrent hepatitis C has improved in recent years, there is as yet no therapy to universally prevent recurrent infection, and tolerability of antivirals remains a matter of concern.

Review article: the treatment of hepatitis C virus recurrence after liver transplantation

BACKGROUND

Recurrent hepatitis C represents a major challenge for the liver transplant community. Given the potentially significant impact that hepatitis C recurrence has on graft and patient survival, several treatment strategies have been utilized to prevent/slow the progression to hepatitis C-related graft failure.

AIM

To review the efficacy and applicability of treatment strategies for managing recurrent hepatitis C.

METHODS

Search of MEDLINE (1990 to December 2006) and national meeting abstracts. Search terms included hepatitis C, liver transplantation, treatment, sustained virological response (SVR), and end of treatment virological response. An emphasis was placed on randomized trials.

RESULTS

The largest study of treatment prior to liver transplantation (n = 124) achieved SVR in 24%. Eight randomized trials (n = 383) examined the efficacy of preemptive therapy with SVR ranging from 0-33%. Eligibility for treatment was low and dose reduction common. Four randomized trials (n = 245; all abstracts) have reported SVR from 33-42% for treating those with histological evidence of recurrent disease.

CONCLUSIONS

Therapies for treating hepatitis C recurrence have limited applicability and tolerability, and they have a low SVR. Based on available results, preemptive therapy is not recommended. Pegylated interferon and ribavirin is currently the preferred choice for treating established recurrence. There is an urgent need for safer and more effective anti-viral therapy in this situation.

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

Liver allograft cirrhosis is a relatively uncommon complication of liver transplantation. Most cases can be attributed to disease recurrence, particularly recurrent hepatitis C. Little is known about the frequency, etiology, and natural history of liver allograft cirrhosis occurring without evidence of recurrent disease. The aim of the present study was to review the clinicopathological features in this group of patients. We retrospectively reviewed data from all adult patients who were transplanted between 1982 and 2002 and survived >12 months after orthotopic liver transplantation (n = 1,287). Cases of histologically proven cirrhosis were identified from histopathological data entered into the Liver Unit Database. A total of 48 patients (3.7%) developed cirrhosis. In 29 of them, cirrhosis could be attributed to recurrent disease (hepatitis C, 11; hepatitis B, 4; autoimmune hepatitis, 4; primary biliary cirrhosis, 2; primary sclerosing cholangitis, 3; nonalcoholic steatohepatitis, 4; alcoholic liver disease, 1). In 9 of the 19 patients without evidence of disease recurrence, another cause of cirrhosis could be identified (de novo autoimmune hepatitis, 4; biliary complications, 4; acquired hepatitis B, 1). In the remaining 10 cases, the cause of cirrhosis remained unknown; their previous biopsies had shown features of chronic hepatitis of uncertain etiology. Three patients in this group died, and the remaining 7 are alive with good graft function 3-12 years after cirrhosis was first diagnosed. The prevalence of "cryptogenic" posttransplant cirrhosis was significantly higher in patients initially transplanted for fulminant seronegative hepatitis (6%) than in those transplanted for other diseases (0.3%). In conclusion, posttransplant cirrhosis without disease recurrence is uncommon, but it is more frequent in patients transplanted for fulminant seronegative hepatitis. Chronic hepatitis is the most frequent underlying pathological process in cases where the cause of cirrhosis remains uncertain.

Natural history of unexplained chronic hepatitis after liver transplantation

Unexplained chronic hepatitis (CH) in the adult liver allograft recipient is not uncommon, but its natural history and clinical significance is unknown. A retrospective study was undertaken of adult liver allograft recipients to determine the frequency and natural history of unexplained CH. We evaluated only those patients who had undergone >or=2 liver biopsies after 6 months and were grafted for indications where recurrent disease could be confidently excluded (alcoholic liver disease [ALD] in those who remained abstinent and fulminant hepatic failure [FHF] from drug reactions). Of 288 patients who were transplanted for ALD or FHF, 30 fulfilled the above criteria. CH was first diagnosed at a median of 15.25 months after transplantation. A total of 24 patients showed mild necroinflammatory changes, and 12 had mild or moderate fibrosis. Liver tests did not reflect the presence or degree of inflammation or fibrosis. After a median of 4 years, necroinflammatory scores were increased in 5; new or progressive fibrosis was noted in 13%; 3 had developed cirrhosis; and 5 developed clinical evidence of portal hypertension. Progressive fibrosis was associated with a high titer of anti-nuclear antibodies (>1:1600) and a portal tract plasma cell infiltrate. There was a trend for correlation between necroinflammatory activity and fibrosis stage, but this did not reach statistical significance (P = 0.06). Serum alkaline phosphatase (P = 0.012) and female gender of the donor (P = 0.033) were associated with progressive fibrosis. Unexplained CH is not uncommon in the liver allograft and may progress to established cirrhosis in a subgroup of patients transplanted for ALD or FHF. Standard liver tests do not reflect the extent of these changes, so protocol liver biopsies may be required to detect these changes. We recommend careful history and follow-up in these patients.