Cholestatic Liver Diseases After Liver Transplant

BM-MSCs overexpressing the Numb enhance the therapeutic effect on cholestatic liver fibrosis by inhibiting the ductular reaction

BACKGROUND

Cholestatic liver fibrosis (CLF) is caused by inflammatory destruction of the intrahepatic bile duct and abnormal proliferation of the small bile duct after cholestasis. Activation of the Notch signaling pathway is required for hepatic stem cells to differentiate into cholangiocytes during the pathogenesis of CLF. Our previous research found that the expression of the Numb protein, a negative regulator of Notch signaling, was significantly reduced in the livers of patients with primary biliary cholangitis and CLF rats. However, the relationship between the Numb gene and CLF is largely unclear. In this study, we investigated the role of the Numb gene in the treatment of bile duct ligation (BDL)-induced CLF.

METHODS

In vivo, bone marrow-derived mesenchymal stem cells (BM-MSCs) with Numb gene overexpression or knockdown obtained using lentivirus transfection were transplanted into the livers of rats with BDL-induced CLF. The effects of the Numb gene on stem cell differentiation and CLF were evaluated by performing histology, tests of liver function, and measurements of liver hydroxyproline, cytokine gene and protein levels. In vitro, the Numb gene was overexpressed or knocked down in the WB-F344 cell line by lentivirus transfection, Then, cells were subjected immunofluorescence staining and the detection of mRNA levels of related factors, which provided further evidence supporting the results from in vivo experiments.

RESULTS

BM-MSCs overexpressing the Numb gene differentiated into hepatocytes, thereby inhibiting CLF progression. Conversely, BM-MSCs with Numb knockdown differentiated into biliary epithelial cells (BECs), thereby promoting the ductular reaction (DR) and the progression of CLF. In addition, we confirmed that knockdown of Numb in sodium butyrate-treated WB-F344 cells aggravated WB-F344 cell differentiation into BECs, while overexpression of Numb inhibited this process.

CONCLUSIONS

The transplantation of BM-MSCs overexpressing Numb may be a useful new treatment strategy for CLF.

The gut-liver axis in cholangiopathies: focus on bile acid based pharmacological treatment

PURPOSE OF REVIEW

This review analyses the main features of primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) and provides an overview of the currently available (bile acid) bile acid related treatments.

RECENT FINDINGS

In PBC, biliary injury is the consequence of a dysregulated intrahepatic and systemic immune response. Given the close association between PSC and inflammatory bowel disease (IBD), the microbiota represents an important factor in the development of PSC. Bile acid based pharmacological treatments could represent promising therapeutic strategies in the management of cholangiopathies.

SUMMARY

Cholangiopathies include a spectrum of diseases resulting in cholestasis, an impairment of bile flow in the biliary tree, leading to biliary obstruction and damage as well as liver inflammation and fibrosis. PSC and PBC are highly heterogeneous cholangiopathies and progressive disorders with defined pathophysiological mechanisms. Curative treatments have not been established, and although their prevalence is low, they are a frequent indication for liver transplantation in the advanced stages of cholangiopathies. These diseases still present with unmet therapeutic strategies, also taking into account that on average 30-40% of patients undergoing liver transplantation will have recurrence of the original illness.

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.

Biliary complications in recipients of living donor liver transplantation: A single-centre study

BACKGROUND

Biliary complications (BCs) after liver transplantation (LT) remain a considerable cause of morbidity, mortality, increased cost, and graft loss.

AIM

To investigate the impact of BCs on chronic graft rejection, graft failure and mortality.

METHODS

From 2011 to 2016, 215 adult recipients underwent right-lobe living-donor liver transplantation (RT-LDLT) at our centre. We excluded 46 recipients who met the exclusion criteria, and 169 recipients were included in the final analysis. Donors’ and recipients’ demographic data, clinical data, operative details and postoperative course information were collected. We also reviewed the management and outcomes of BCs. Recipients were followed for at least 12 mo post-LT until December 2017 or graft or patient loss.

RESULTS

The overall incidence rate of BCs including biliary leakage, biliary infection and biliary stricture was 57.4%. Twenty-seven (16%) patients experienced chronic graft rejection. Graft failure developed in 20 (11.8%) patients. A total of 28 (16.6%) deaths occurred during follow-up. BCs were a risk factor for the occurrence of chronic graft rejection and failure; however, mortality was determined by recurrent hepatitis C virus infection.

CONCLUSION

Biliary complications after RT-LDLT represent an independent risk factor for chronic graft rejection and graft failure; nonetheless, effective management of these complications can improve patient and graft survival.

Liver Disease and Hemostasis (Review) Part 2. Cholestatic Liver Disease and Hemostasis

The presence or development of liver disorders can significantly complicate the course of critical illness and terminal conditions. Systemic hemostatic disorders are common in Intensive Care Units patients with cholestatic liver diseases, so the study of the mechanisms of their development can contribute to the understanding of the development of multiorgan failure in critical illness.

The review discusses current data on changes in hemostatic parameters in patients with cholestatic liver diseases, proposes a mechanism for the development of such disorders, which involve interactions of phospholipids with platelet and endotheliocyte membranes. It is suggested that a trend for thrombosis in patients with cholestatic liver disease is due to increased accumulation of bile acids in the systemic circulation. Available data demonstrate that the antiphospholipid syndrome may predispose to the formation of blood clots due to alterations of phospholipid composition of membranes of platelets and vascular endothelial cells by circulating antiphospholipid antibodies. Clarifying the mechanisms contributing to changes of the blood coagulation system parameters in liver disorders will aid to development of optimal correction of hemostatic disorders in patients with chronic liver diseases.

Range of Normal Serum Aminotransferase Levels in Liver Transplant Recipients

Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) are used to monitor liver transplant recipients (LTR) but the reference range and context of its use is not well defined. We aimed to determine the healthy ranges in LTR without chronic liver disease.

METHODS

One hundred and three LTR without chronic liver disease based on serology, transient elastography with controlled attenuated parameter, and ultrasound were included. A healthy range of aminotransferases was set to 95th percentile. An updated normal aminotransferase range was used to detect recurrence in post-liver transplantation (LT) with hepatitis C virus (HCV) and nonalcoholic fatty liver disease (NAFLD).

RESULTS

The normal ALT and AST range was 0 to 57 and 0 to 54 IU/L, respectively, in LTR and was not affected by age, sex, obesity, or choice of immunosuppressant. The diagnostic performance of serum ALT and AST to detect recurrence of NAFLD by a controlled attenuated parameter was poor with area under the receiver operating characteristic curve of 0.573 (95% confidence interval 0.493, 0.655; P = .08) and 0.537 (0.456, 0.618; P = .4), respectively. In contrast, the diagnostic performance of ALT and AST to detect recurrence of HCV after LT was 0.906 (0.868, 0.944; P < .001) and 0.925 (0.890, 0.959; P < .001), respectively.

CONCLUSION

The updated aminotransferase range in LTR is higher than the general population and accurate for detecting recurrent HCV, but not NAFLD.

Primary Biliary Cholangitis and Primary Sclerosing Cholangitis

Cholestatic liver diseases encompass a broad spectrum of pathologies, with the core injury occurring at the level of cholangiocytes and progressing to hepatic fibrosis and liver dysfunction. Primary biliary cholangitis and primary sclerosing cholangitis are the most significant progressive cholangiopathies in adults. Although rare, they commonly evolve to liver failure and need for liver transplantation. Despite recent advances in the basic knowledge of these cholangiopathies, the pathogenesis is still elusive. Targeted treatments to prevent disease progression and to preclude malignancy are not yet available. This review will address the general clinical features of both diseases, analyze their commonalities and differences, and provide a state-of-the art overview of the currently available therapeutics.

Anti-inflammatory, anti-oxidative stress and novel therapeutic targets for cholestatic liver injury

Cholestasis is a pathological process in which bile drainage is poor for a variety of reasons. Many studies have shown that cholestatic liver injury is a neutrophil-mediated inflammatory response, and oxidative stress induced by neutrophils is the main mechanism of liver cell death. The literature summarizes the bile acid signaling pathway, the neutrophil chemotaxis recruitment process during cholestasis, and the oxidative stress damage produced by neutrophil activation, summarizes the latest research progress. Sphingosine-1-phosphate receptor (S1PR) is a potential therapeutic target for cholestasis that reduces neutrophil aggregation without inhibiting systemic immune status. Early growth response factor 1 (Egr-1) may play a central role in the inflammation induced by cholestasis, and it is also a potential therapeutic target to inhibit the inflammation induced by cholestasis. Strengthening the antioxidant system of hepatocytes to cope with oxidative stress of neutrophils is a feasible treatment for cholestatic liver injury.

The gastroenterologist's guide to management of the post-liver transplant patient

The management of the post-liver transplant patient is complex and involves a large interdisciplinary team. After referral to a transplant center, evaluation and listing, and eventual transplantation, the patient is cared for closely by the transplant center. Once deemed ready for discharge, the patient returns to the primary care provider for ongoing management of the various issues that increase in incidence post transplant such as osteoporosis, cardiovascular, and renal diseases, as well as metabolic syndrome. The role of the gastroenterologist is not well defined, but certainly, he or she may be called upon for the initial evaluation and ongoing management of gastrointestinal as well as hepatobiliary issues. This includes but is not limited to the investigation of abnormal liver tests, non-specific gastrointestinal complaints such as nausea, vomiting, or diarrhea, biliary complications, and even recurrent hepatic disease. Having familiarity with post-transplant immunosuppressive agents, drug interactions, and potential infectious and malignancy-related complications of transplant is essential, as the primary gastroenterologist may be expected in some situations to field the initial work-up, if patient access to the transplant center is limited. The aim of this review is to summarize the gastroenterologist's role in the management of the post-liver transplant patient.

Patient and Graft Survival: Biliary Complications after Liver Transplantation

BACKGROUND

Biliary complications (BCs) affect up to to 34% of liver transplant recipients and are a major source of morbidity and cost. This is a 13-year review of BCs after liver transplantation (LT) at a tertiary care center.

STUDY DESIGN

We conducted a single-center retrospective review of our prospective database to assess BCs in adult (aged 18 years or older) liver transplant recipients during a 13-year period (2002 to 2014). Biliary complications were divided into 3 subgroups: leak alone (L), stricture alone (S), and both leak and strictures (LS). Controls (no BCs) were used for comparison.

RESULTS

There were 1,041 adult LTs performed during the study period; BCs developed in 239 (23%) of these patients: 55 (23%) L, 148 (62%) S, and 36 (15%) LS. One hundred and two (43%) were early (less than 30 d). Surgical revision was required in 42 cases (17%) (30 L, 10 LS, and 2 S), while the remaining 197 (83%) were managed nonsurgically (25 L, 26 LS, and 146 S), with a mean of 4.2 interventions/patient. One-, 3-, and 5-year overall patient and graft survival was significantly reduced in patients with bile leaks (84%, 71%, and 68% and 76%, 67%, and 64%, respectively) compared with controls (90%, 84%, and 78% and 88%, 81%, and 76%, respectively [p < 0.05]). Patients with BCs had higher incidence of cholestatic liver disease, higher pre-LT bilirubin, higher use of T-tubes, higher use of donor after cardiac death grafts, and higher rates of acute rejection (p < 0.05). Patients with BCs had longer ICU and hospital stays and higher rates of 30- and 90-day readmissions (p < 0.01). Multivariate analysis identified cholestatic liver disease, Roux-en-Y anastomosis, donor risk index >2, and T-tubes as independent BC predictors.

CONCLUSIONS

Biliary complications after LT can significantly decrease patient and graft survival rates. Careful donor and recipient selection and attention to anastomotic technique can reduce BCs and improve outcomes.