Primary biliary cirrhosis has high wait-list mortality among patients listed for liver transplantation

The Spillover Effects of Extending Liver Transplantation to Patients with Colorectal Liver Metastases: A Discrete Event Simulation Analysis

BACKGROUND

Liver transplantation is an alternative treatment for patients with nonresectable colorectal cancer liver-only metastases (CRLM); however, the potential effects on wait-list time and life expectancy to other patients on the transplant waiting list have not been considered. We explored the potential effects of expanding liver transplantation eligibility to include patients with CRLM on wait-list time and life expectancy in Norway.

METHODS

We developed a discrete event simulation model to reflect the Norwegian liver transplantation waiting list process and included 2 groups: 1) patients currently eligible for liver transplantation and 2) CRLM patients. Under 2 alternative CRLM-patient transplant eligibility criteria, we simulated 2 strategies: 1) inclusion of only currently eligible patients (CRLM patients received standard-of-care palliative chemotherapy) and 2) expanding waiting list eligibility to include CRLM patients under 2 eligibility criteria. Model outcomes included median waiting list time, life expectancy, and total life-years.

RESULTS

For every additional CRLM patient listed per year, the overall median wait-list time, initially 52 d, increased by 8% to 11%. Adding 2 additional CRLM patients under the most restrictive eligibility criteria increased the CRLM patients' average life expectancy by 10.64 y and decreased the average life expectancy for currently eligible patients by 0.05 y. Under these assumptions, there was a net gain of 149.61 life-years over a 10-y programmatic period, which continued to increase under scenarios of adding 10 CRLM patients to the wait-list. Health gains were lower under less restrictive CRLM eligibility criteria. For example, adding 4 additional CRLM patients under the less restrictive eligibility criteria increased the CRLM patients' average life expectancy by 5.64 y and decreased the average life expectancy for currently eligible patients by 0.12 y. Under these assumptions, there was a net gain of 96.36 life-years over a 10-y programmatic period, which continued to increase up to 7 CRLM patients.

CONCLUSIONS

Our model-based analysis enabled the consideration of the potential effects of enlisting Norwegian CRLM patients for liver transplantation on wait-list time and life expectancy. Enlisting CRLM patients is expected to increase the total health effects, which supports the implementation of liver transplantation for CRLM patients in Norway.

HIGHLIGHTS

Given the Norwegian donor liver availability, adding patients with nonresectable colorectal cancer liver-only metastases (CRLM) to the liver transplantation waiting list had an overall modest, but varying, impact on total waiting list time.Survival gains for selected CRLM patients treated with liver transplantation would likely outweigh the losses incurred to patients listed currently.To improve the total life-years gained in the population, Norway should consider expanding the treatment options for CRLM patients to include liver transplantation.Other countries may also have an opportunity to gain total life-years by extending the waiting list eligibility criteria; however, country-specific analyses are required.

Influence of socioeconomic factors on liver transplant survival outcomes in patients with autoimmune liver disease in the United States

INTRODUCTION AND OBJECTIVES

Autoimmune liver diseases (AILDs): autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC) have different survival outcomes after liver transplant (LT). Outcomes are influenced by factors including disease burden, medical comorbidities, and socioeconomic variables.

MATERIALS AND METHODS

Using the United Network for Organ Sharing database (UNOS), we identified 13,702 patients with AILDs listed for LT between 2002 and 2021. Outcomes of interest were waitlist removal, post-LT patient survival, and post- LT graft survival. A stepwise multivariate analysis was performed adjusting for transplant recipient gender, race, diabetes mellitus, model for end-stage liver disease (MELD) score, and additional social determinants including the presence of education, reliance on public insurance, working for income, and U.S. citizenship status.

RESULTS

Lack of college education and having public insurance increased the risk of waitlist removal (HR, 1.13; 95 % CI, 1.05-1.23, and HR, 1.09; 95 % CI, 1.00-1.18; respectively), and negatively influenced post-LT patient survival (HR, 1.16; 95 % CI, 1.06-1.26, and HR, 1.15; 95 % CI, 1.06-1.25; respectively) and graft survival (HR, 1.13; 95 % CI, 1.05-1.23, and HR, 1.15; 95 % CI, 1.06-1.25; respectively). Not working for income proved to have the greatest detrimental impact on both patient survival (HR, 1.41; 95 % CI, 1.24-1.6) and graft survival (HR, 1.21; 95 % CI, 1.09-1.35).

CONCLUSIONS

Our study highlights that lack of college education and public insurance have a detrimental impact on waitlist mortality, patient survival, and graft survival. Not working for income negatively affects post-LT survival outcomes. Not having U.S. citizenship does not affect survival outcomes in AILDs patients.

Two Decades of Liver Transplants for Primary Biliary Cholangitis: A Comparative Study of Living Donors vs. Deceased Donor Liver Transplantations

Primary biliary cholangitis (PBC) prompts liver transplantation (LT) due to cholestasis, cirrhosis, and liver failure. Despite lower MELD scores, recent studies highlight higher PBC waitlist mortality, intensifying the need for alternative transplantation strategies. Living donor liver transplant (LDLT) has emerged as a solution to the organ shortage. This study compares LDLT and deceased donor liver transplant (DDLT) outcomes in PBC patients via retrospective analysis of the UNOS database (2002-2021). Patient survival, graft failure, and predictors were evaluated through Kaplan-Meier and Cox-proportional analyses. Among 3482 DDLTs and 468 LDLTs, LDLT showed superior patient survival (92.3%, 89.1%, 87.6%, 85.0%, 77.2% vs. 91.5%, 88.3%, 86.3%, 82.2%, 71.0%; respectively; p = 0.02) with no significant graft survival difference at 1-, 2-, 3-, 5-, and 10-years post-LT (91.0%, 88.0%, 85.7%, 83.0%, 75.4% vs. 90.5%, 87.4%, 85.3%, 81.3%, 70.0%; respectively; p = 0.06). Compared to DCD, LDLT showed superior patient and graft survival (p < 0.05). Younger male PBC recipients with a high BMI, diabetes, and dialysis history were associated with mortality and graft failure (p < 0.05). Our study showed that LDLT had superior patient survival to DDLT. Predictors of poor post-LT outcomes require further validation studies.

Primary biliary cholangitis: Epidemiology, prognosis, and treatment

Primary biliary cholangitis (PBC) is a chronic cholestatic autoimmune liver disease characterized by a destructive, small duct, and lymphocytic cholangitis, and marked by the presence of antimitochondrial antibodies. The incidence and prevalence of PBC vary widely in different regions and time periods, and although disproportionally more common among White non-Hispanic females, contemporary data show a higher prevalence in males and racial minorities than previously described. Outcomes largely depend on early recognition of the disease and prompt institution of treatment, which, in turn, are directly influenced by provider bias and socioeconomic factors. Ursodeoxycholic acid remains the initial treatment of choice for PBC, with obeticholic acid and fibrates (off-label therapy) reserved as add-on therapy for the management of inadequate responders or those with ursodeoxycholic acid intolerance. Novel and repurposed drugs are currently at different stages of clinical development not only for the treatment of PBC but also for its symptomatic management. Here, we summarize the most up-to-date data regarding the epidemiology, prognosis, and treatment of PBC, providing clinically useful information for its holistic management.

Platelets mediate acute hepatic microcirculatory injury in a protease-activated-receptor-4-dependent manner after extended liver resection

BACKGROUND

Small-for-size syndrome (SFSS) is a major complication following extended liver resection. The role of platelets in the early development of SFSS remains to be cleared. We aimed to investigate the impact of platelets and PAR-4, a receptor for platelet activation, on the acute phase microcirculatory injury after liver resection by in vivo microscopy analyzing the changes in leukocyte recruitment, platelet-neutrophil interaction, and microthrombosis-induced perfusion failure.

METHODS

Sixty-percent partial hepatectomy (PH) models using C57BL/6 mice receiving platelet depletion with anti-GPIbα, PAR-4 blockade with tcY-NH2, or vehicle treatment with saline were used. Sham-operated animals served as controls. Epifluorescence microscopic analysis was performed 2 h after PH to quantify the leukocyte recruitment and microcirculatory changes. Sinusoidal neutrophil recruitment, platelet-neutrophil interaction, and microthrombosis were evaluated using two-photon microscopy. ICAM-1 expression and liver liver injury were assessed in tissue/blood samples.

RESULTS

The increments of leukocyte recruitment in post-sinusoidal venules and sinusoidal perfusion failure, the upregulation of ICAM-1 expression, and the deterioration of liver function 2 h after 60% PH were alleviated in the absence of platelets or by PAR-4 blockade. Intensified platelet-neutrophil interaction and microthrombosis in sinusoids were observed 2 h after 60% PH, which significantly attenuated after PAR-4 blockade.

CONCLUSION

Platelets play a critical role in acute liver injury after extended liver resection within 2 h. The deactivation of platelets via PAR-4 blockade ameliorated liver function deterioration by suppressing early leukocyte recruitment, platelet-neutrophil interaction, and microthrombosis in hepatic sinusoids.

Incomplete response to ursodeoxycholic acid in primary biliary cholangitis: criteria, epidemiology, and possible mechanisms

INTRODUCTION

As a common autoimmune disease with the characteristic of early complication, primary biliary cholangitis (PBC) leads to an increasing number of mortalities among people with end-stage liver disease (ESLD) waiting for liver transplantation. Ursodeoxycholic acid (UDCA) is the only approved first-line medicine for PBC, and a good response to treatment could acquire an ideal prognosis. Patients with poor UDCA response usually have more adverse outcomes and worse survival, therefore, the management of this group become a major consideration.

AREAS COVERED

Due to the complexity of race and environment for PBC, different criteria for UDCA response exhibit various predictive performances. Factors affecting UDCA response conditions include gender, age, ethnicity, serum indicators, auto-antibodies, and autoimmune comorbidities, while no agreement has been reached. In this review, we mainly focus on cellular senescence, immune-mediated damage, and vitamin D deficiency as possible mechanisms for UDCA non-responders.

EXPERT OPINION

The pathogenesis of PBC has yet to be clarified. Immunology-related mechanisms and therapy targets ought to be the main effort made for further study. Irrespective of the response condition, UDCA is recommended for routine administration in all PBC patients without contraindication. Ongoing clinical trials of second-line and additional therapy exhibit promising prospects.

Liver Transplantation for Primary Biliary Cholangitis

Despite a significant increase in the total number of liver transplants (LTs) performed over the last 3 decades, primary biliary cholangitis (PBC) has become an uncommon indication for LT, which likely reflects the benefits of earlier diagnosis and available treatment, such as ursodeoxycholic acid (UDCA). Nonetheless, LT remains the only cure for patients with progressive PBC despite medical therapy with survival rates that are among the highest of all indications for LT. Post-LT PBC patients, however, are at increased risk of rejection and disease recurrence.

The Impact of Primary Liver Disease and Social Determinants in a Mixed Donor Liver Transplant Program: A Single-Center Analysis

Organ allocation in liver transplantation (LT) remains imperfect. Periodic center reviews ensure programs transparently evaluate the impact of practice on access to transplantation, reflecting, in particular, patient (primary disease, social determinants) and program (deceased versus live donation) factors. Adult Ontario residents waitlisted for first LT at Toronto General Hospital from November 2012 to May 2019 were reviewed. Analyses were performed between distance to transplant center, income, education level, population density and primary liver disease, with LT, deceased donor liver transplant (DDLT), living donor liver transplant (LDLT), and delisting. Of 1735 listed patients, 549 were delisted (32%), while 1071 were transplanted (62%), with 819 DDLT recipients (76%) and 252 LDLT recipients (24%), while 115 (7%) remained actively listed at data census. On univariate analysis, DDLT recipients lived 30% closer (median 39.7 versus 60.6 km; P < 0.001), lived in more populous areas (median 8501.0 versus 6868.5 people in a 1-km radius; P < 0.001), and resided in households that annually earned 10% less (median $92,643.17 versus $102,820.89 Canadian dollars; P < 0.001) compared with LDLT recipients. These findings with population density and income differences between DDLT versus LDLT receival remained significant on multivariate modeling even when accounting for primary liver disease. Primary liver disease was a statistically significant factor on multivariate analyses in LT receival (P = 0.001) as well as DDLT versus LDLT receival (P < 0.001). Of patients listed for end-stage liver disease, more patients with autoimmune cholestatic liver diseases received LDLT (34%-41%) than DDLT (27%-30%); this contrasted with patients with noncholestatic diseases LDLT (8%-19%) versus DDLT (37%-59%) receival (P < 0.001). Review of transplant allocation in a large mixed-donor North American liver transplant program demonstrates how patient social determinants and primary liver disease etiology continue to be significantly associated with ultimate transplantation.

Excess liver transplant waitlist mortality for patients with primary biliary cholangitis under MELD-Na allocation

BACKGROUND

Historically, patients with primary biliary cholangitis (PBC) experience waitlist mortality and low rates of liver transplant (LT). Herein, the impact of MELD-Na based allocation on PBC waitlist mortality was examined.

METHODS

Adult patients with PBC were compared to those with alcohol-related liver disease (ALD) or non-alcoholic steatohepatitis (NASH) listed for LT from 2013 to 2019 in OPTN. Competing risk regression evaluated waitlist mortality in the MELD and MELD-Na eras using propensity score weights.

RESULTS

Overall, 1508 patients with PBC, 13581 with ALD, and 10455 with NASH were examined. In the MELD-Na era, 24-month cumulative incidence of waitlist mortality for PBC was 23.0% (95%CI 19.7-26.5%), ALD 13.9% (95%CI 13.1-14.8%), and NASH 20.0% (95%CI 18.9-21.2%). Using propensity score weights, adjusted risk of waitlist mortality was higher for PBC versus ALD (HR = 1.45, 95%CI 1.22-1.71) and NASH (HR = 1.32, 95%CI 1.14-1.55). Furthermore, among PBC, waitlist mortality risk per five-point elevation in MELD-Na (HR = 1.22, 95%CI 1.11-1.35) and Karnofsky score ≤30% (HR = 2.02, 95%CI 1.39-2.92) was significantly higher than among ALD (HR = 1.08, 95%CI 1.04-1.13; HR = 1.28, 95%CI 1.10-1.49) and NASH (HR = 1.05, 95%CI 1.00-1.09; HR = 1.16, 95%CI .99-1.37; all P-interactions < .05).

CONCLUSIONS

The MELD-Na score continues to underestimate risk of waitlist death for patients with PBC relative to ALD and NASH and highlights need for additional score modifications or exceptions.

Primary biliary cholangitis has the highest waitlist mortality in patients with cirrhosis and acute on chronic liver failure awaiting liver transplant

BACKGROUND

Data are sparse on etiology specific outcomes on waitlist (WL) and post-transplant outcomes among patients with acute on chronic liver failure (ACLF).

METHODS AND RESULTS

In a retrospective cohort of 14,774 adults from United network for organ sharing (UNOS) database listed for Liver transplantation (LT) with cirrhosis and ACLF (January 2013-June 2019), 40% were due to alcohol-associated liver disease (ALD), followed by hepatitis C virus (HCV) at 20%, non-alcoholic steatohepatitis (19%), cryptogenic cirrhosis (7%), autoimmune hepatitis (5%), primary sclerosing cholangitis (PSC) at 3%, and 2% each for hepatitis B, primary biliary cholangitis (PBC), and metabolic etiology. Using competing risk analysis, cumulative risk of WL mortality was highest for PBC at 20.5% and lowest for PSC at 13.3%, P < .001. Compared with ALD as reference, WL mortality was higher for PBC (1.45 [1.16-1.82]), and similar for other etiologies, P < .001. Of this cohort, 9650 (65.3%) patients received LT, with 1-year. patient survival of 91.6% for PBC, worst for cryptogenic cirrhosis (89.5%) and best for PSC and ALD (93.4%), P < .001.

CONCLUSION

Among listed candidates with ACLF, those with PBC have highest WL mortality 1-year. post-transplant survival was excellent among recipients for PBC. If these findings are validated in prospective studies, liver disease etiology should be considered for LT selection among patients in ACLF.

Validating a novel score based on interaction between ACLF grade and MELD score to predict waitlist mortality

BACKGROUND & AIMS

Among candidates listed for liver transplant (LT), the model for end-stage liver disease (MELD) score may not capture acute-on-chronic liver failure (ACLF) severity. Data on the interaction between ACLF and MELD score in predicting waitlist mortality are scarce.

METHODS

We analyzed the UNOS database (01/2002 to 06/2018) for LT listings in adults with cirrhosis and ACLF (without hepatocellular carcinoma). ACLF grades 1, 2, 3a, and 3b- were defined using the modified EASL-CLIF criteria.

RESULTS

Of 18,416 candidates with ACLF at listing (mean age 54 years, 69% males, 63% Caucasians), 90-day waitlist mortality (patient death or being too sick for LT) was 21.6% (18%, 20%, 25%, and 39% for ACLF grades 1, 2, 3a, and 3b, respectively). Using a Fine and Gray regression model, we identified an interaction between MELD and ACLF grade, with ACLF having a higher impact at lower MELD scores. Other variables included candidate's age, sex, liver disease etiology, listing MELD, ACLF grade, obesity, and performance status. A score developed using parameter estimates from the interaction model on the derivation cohort (n = 9,181) stratified the validation cohort (n = 9,235) into quartiles: Q1 (score <10.42), Q2 (10.42-12.81), Q3 (12.82-15.50), and Q4 (>15.50). Waitlist mortality increased with each quartile from 13%, 18%, 23%, and 36%, respectively. Observed vs. expected waitlist mortality deciles in the validation cohort showed good calibration (goodness of fit p = 0.98) and correlation (R = 0.99).

CONCLUSION

Among selected candidates who have ACLF at listing, MELD score and ACLF interact in predicting cumulative risk of 90-day waitlist mortality, with higher impact of ACLF grade at lower listing MELD score. Validating these findings in large prospective studies will support consideration of both MELD and ACLF when prioritizing transplant candidates and allocating liver grafts.

LAY SUMMARY

In patients with cirrhosis listed for liver transplantation, the presence of multiorgan failure, a condition referred to as acute-on-chronic liver failure, is associated with high waiting list mortality rates. Current organ allocation policy disadvantages patients with this condition. This study describes and validates a new scoring method that performs better than the currently available scoring systems. Further validation of this approach may reduce the deaths of patients with cirrhosis and acute-on-chronic liver failure on the transplant waiting list.

Circulating Bile Acids in Liver Failure Activate TGR5 and Induce Monocyte Dysfunction

BACKGROUND & AIMS

Retention of bile acids in the blood is a hallmark of liver failure. Recent studies have shown that increased serum bile acid levels correlate with bacterial infection and increased mortality. However, the mechanisms by which circulating bile acids influence patient outcomes still are elusive.

METHODS

Serum bile acid profiles in 33 critically ill patients with liver failure and their effects on Takeda G-protein-coupled receptor 5 (TGR5), an immunomodulatory receptor that is highly expressed in monocytes, were analyzed using tandem mass spectrometry, novel highly sensitive TGR5 bioluminescence resonance energy transfer using nanoluciferase (NanoBRET, Promega Corp, Madison, WI) technology, and in vitro assays with human monocytes.

RESULTS

Twenty-two patients (67%) had serum bile acids that led to distinct TGR5 activation. These TGR5-activating serum bile acids severely compromised monocyte function. The release of proinflammatory cytokines (eg, tumor necrosis factor α or interleukin 6) in response to bacterial challenge was reduced significantly if monocytes were incubated with TGR5-activating serum bile acids from patients with liver failure. By contrast, serum bile acids from healthy volunteers did not influence cytokine release. Monocytes that did not express TGR5 were protected from the bile acid effects. TGR5-activating serum bile acids were a risk factor for a fatal outcome in patients with liver failure, independent of disease severity.

CONCLUSIONS

Depending on their composition and quantity, serum bile acids in liver failure activate TGR5. TGR5 activation leads to monocyte dysfunction and correlates with mortality, independent of disease activity. This indicates an active role of TGR5 in liver failure. Therefore, TGR5 and bile acid metabolism might be promising targets for the treatment of immune dysfunction in liver failure.

Review article: pathophysiology and management of primary biliary cholangitis

BACKGROUND

Primary biliary cholangitis (PBC), an immune-mediated disease characterised by destruction of intrahepatic bile ducts, results in progressive damage to the biliary tree, cholestasis and ultimately advanced liver disease. In the last decade, advances in practice have improved clinical care, driven novel therapeutic options and improved risk stratification tools.

AIMS

To provide an overview of the disease characteristics of PBC and review a patient-centred management approach for the clinical team caring for those with PBC.

METHODS

We reviewed the current literature and guidelines on PBC with a focus on management and therapies.

RESULTS

A confident diagnosis of PBC is usually made based on serum liver tests and immune serology. Management of PBC should focus on three main 'process' pillars: (a) treat and risk-stratify through use of biochemical and prognostic criteria; (b) manage concurrent symptoms and other associated diseases; and (c) stage disease, monitor progression and prevent complications. With ongoing complexities in management, including a newly licensed therapy (obeticholic acid) and alternative non-licensed treatments and ongoing clinical trials, discussion with PBC expert centres is encouraged.

CONCLUSIONS

PBC is a dynamic disease wherein current treatment goals have become appropriately ambitious. Goals of care should prioritise prevention of end-stage liver disease and amelioration of patient symptom burden for all.

Prioritization for liver transplantation using the MELD score in Chile: Inequities generated by MELD exceptions.: A collaboration between the Chilean Liver Transplant Programs, the Public Health Institute and the National Transplant Coordinator

INTRODUCTION AND AIM

The MELD score has been established as an efficient and rigorous prioritization system for liver transplant (LT). Our study aimed to evaluate the effectiveness of the MELD score as a system for prioritization for LT, in terms of decreasing the dropout rate in the waiting list and maintaining an adequate survival post-LT in Chile.

MATERIALS AND METHODS

We analyzed the Chilean Public Health Institute liver transplant registry of candidates listed from October 15th 2011 to December 31st 2014. We included adult candidates (>15 years old) listed for elective cadaveric LT with a MELD score of 15 or higher. Statistical analysis included survival curves (Kaplan-Meier), log-rank statistics and multivariate logistic regression.

RESULTS

420 candidates were analyzed. Mean age was 53.6±11.8 years, and 244 were men (58%). Causes of LT included: Liver cirrhosis without exceptions (HC) 177 (66.4%); hepatocellular carcinoma (HCC) 111 (26.4%); cirrhosis with non-HCC exceptions 102 (24.3%) and non-cirrhotic candidates 30 (7.2%). LT rate was 43.2%. The dropout rate was 37.6% at 1-year. Even though the LT rate was higher, the annual dropout rate was significantly higher in cirrhotic candidates (without exceptions) compared with cirrhotics with HCC, and non-HCC exceptions plus non-cirrhotic candidates (47.9%; 37.2% and 24.2%, respectively, with p=0.004). Post-LT survival was 84% per year, with no significant differences between the three groups (p=0.95).

CONCLUSION

Prioritization for LT using the MELD score system has not decreased the dropout rate in Chile (persistent low donor's rate). Exceptions generate inequities in dropout rate, disadvantaging patients without exceptions.

Outcomes of Liver Transplant Candidates with Primary Biliary Cholangitis: The Data from the Scientific Registry of Transplant Recipients

BACKGROUND

Primary biliary cholangitis (PBC) is progressive and can cause end-stage liver disease necessitating a liver transplant (LT). PBC patients may be disadvantaged on LT waitlist due to MELD-based priority listing or other factors.

AIM

The aim was to assess waitlist duration, waitlist mortality, and post-LT outcomes of PBC patients.

METHODS

The Scientific Registry of Transplant Recipients data for 1994-2016 was utilized. Adult patients with PBC without hepatocellular carcinoma (HCC) were selected. Their clinico-demographic parameters and waitlist and post-transplant outcomes were compared to those of patients with hepatitis C (HCV) without HCC.

RESULTS

Out of 223,391 listings for LT in 1994-2016, 8133 (3.6%) was for PBC without HCC. Mean age was 55.5 years, 76.9% white, 86.2% female, mean MELD score 21, 6.6% retransplants. There were 52,017 patients with hepatitis C included for comparison. The mean waitlist mortality was 17.9% for PBC and 17.6% for HCV (p > 0.05). The average transplantation rate was 57.7% for PBC and 53.3% for HCV (p < 0.0001), while waitlist dropout (death or removal due to deterioration) rate was 25.0% for PBC and 25.4% for HCV (p > 0.05). There was no significant difference in median waiting duration till transplantation between PBC patients and HCV after 2002 (103 vs. 95 days, p > 0.05). Post-LT mortality and graft loss rates were significantly lower in PBC than in HCV patients (all p < 0.02).

CONCLUSIONS

Despite no evidence of impaired waitlist outcomes and favorable post-transplant survival in patients with PBC, there is still a high waitlist dropout rate suggesting the presence of an unmet need for effective treatment.

Mortality on the UNOS Waitlist for Patients with Autoimmune Liver Disease

BACKGROUND

Outcomes on the liver transplant waitlist can vary by etiology. Our aim is to investigate differences in waitlist mortality of autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC) using the United Network for Organ Sharing (UNOS) database.

METHODS

We identified patients who were listed for liver transplantation from 1987 to 2016 with a primary diagnosis of AIH, PBC, or PSC. We excluded patients with overlap syndromes, acute hepatic necrosis, missing data, and those who were children. The primary outcome was death or removal from the waitlist due to clinical deterioration. We compared waitlist survival using competing risk analysis.

RESULTS

Between 1987 and 2016, there were 7412 patients listed for liver transplant due to AIH, 8119 for PBC, and 10,901 for PSC. Patients with AIH were younger, more likely to be diabetic, and had higher listing model for end-stage liver disease (MELD) scores compared to PBC and PSC patients. Patients with PBC and AIH were more likely to be removed from the waitlist due to death or clinical deterioration. On competing risk analysis, AIH patients had a similar risk of being removed from the waitlist compared to those with PBC (subdistribution hazard ratio (SHR) 0.94, 95% CI 0.85-1.03) and higher risk of removal compared to those with PSC (SHR 0.8, 95% CI 0.72 to 0.89).

CONCLUSION

Autoimmune hepatitis carries a similar risk of waitlist removal to PBC and a higher risk than PSC. The etiology of this disparity is not entirely clear and deserves further investigation.

Trends in liver transplantation for primary biliary cholangitis in Europe over the past three decades

BACKGROUND

The importance of primary biliary cholangitis as an indication for liver transplantation has probably been influenced by the introduction of therapies, and changes in selection criteria and disease epidemiology.

AIMS

To assess the time trends in liver transplantation for primary biliary cholangitis and to evaluate the characteristics of the patient population during the past three decades.

METHODS

Patients undergoing liver transplantation from 1986 to 2015 in centres reporting to the European Liver Transplantation Registry were included. We excluded combined organ transplantations and patients <18 years. Trends were assessed using linear regression models.

RESULTS

We included 112 874 patients, of whom 6029 (5.3%) had primary biliary cholangitis. After an initial increase in the first decade, the annual number of liver transplantation for primary biliary cholangitis remained stable at around 200. The proportion of liver transplantations for primary biliary cholangitis decreased from 20% in 1986 to 4% in 2015 (P < 0.001). Primary biliary cholangitis was the only indication showing a consistent proportional decrease throughout all decades. From the first to the third decade, the age at liver transplantation increased from 54 (IQR 47-59) to 56 years (IQR 48-62) and the proportion of males increased from 11% to 15% (both P < 0.001).

CONCLUSIONS

We have found a proportional decrease in primary biliary cholangitis as indication for liver transplantation. However, despite treatment with ursodeoxycholic acid and improved disease awareness, the absolute annual number of liver transplantations has stabilised.

Accuracy of the Pediatric End-stage Liver Disease Score in Estimating Pretransplant Mortality Among Pediatric Liver Transplant Candidates

IMPORTANCE

Fair allocation of livers between pediatric and adult recipients is critically dependent on the accuracy of mortality estimates afforded by the Pediatric End-stage Liver Disease (PELD) and Model for End-stage Liver Disease, respectively. Widespread reliance on exceptions for pediatric recipients suggests that the 2 systems may not be comparable.

OBJECTIVE

To evaluate the accuracy of the PELD score in estimating 90-day pretransplant mortality among pediatric patients on the United Network for Organ Sharing (UNOS) waiting list.

DESIGN, SETTING, AND PARTICIPANTS

Patients who were listed from February 27, 2002, to March 31, 2014, for primary liver transplant were included in this retrospective analysis and were followed up for at least 2 years through June 17, 2016. The study analyzed 2 cohorts using the UNOS Standard Transplant Analysis and Research data files. The full cohort comprised 4298 patients (<18 years of age) who had chronic liver disease (excluding cancer). The reduced cohort (n = 2421) excluded patients receiving living donor transplantation or PELD exception points.

MAIN OUTCOMES AND MEASURES

Observed and expected 90-day pretransplant mortality rates evaluated at 10-point interval PELD levels.

RESULTS

Among the 4298 patients in the full cohort (mean [SD] age, 2.5 [4.2] years; 2251 [52.4%] female; 2201 [51.2%] white), PELD scores and mortality were concordant (C statistic, 0.8387 [95% CI, 0.8191-0.8584] for the full cohort and 0.8123 [95% CI, 0.7919-0.8327] for the reduced cohort). However, the estimated 90-day mortality using the PELD score underestimated the actual probability of death by as much as 17%.

CONCLUSIONS AND RELEVANCE

With use of the PELD score, the ranking of risk among children was preserved, but direct comparisons between adult and pediatric candidates were not accurate. Children with chronic liver disease who are in need of transplant may be at a disadvantage compared with adults in a similar situation.

PBC-transplantation and disease recurrence

Despite near universal use of ursodeoxycholic acid (UDCA) several patients with PBC still progress to liver transplant (LT) or death. Pruritus and fatigue are the most common symptoms. Liver transplantation for pruritus is highly effective but fatigue will not disappear in the majority of the patients. In contrast to other liver diseases, portal hypertension may develop in pre-cirrhotic patients with PBC. Patients with PBC have an incidence rate of 3.4 hepatocellular carcinoma cases for every 1000 patient-years and risk factors are advanced stage of the disease and male sex. For the appropriate timing of LT the utility of prognostic models (bilirubin, Mayo risk score and MELD, in particular) and standard exception points in case of HCC are established. However, recent data from different part of the world demonstrated that PBC patients compared to patients with PSC have higher waiting-list mortality. Hyperlipidemia can be present in up to 80% of the patients but there is no evidence for an elevated cardiovascular risk, certainly not in relationship with LT. Patients transplanted for PBC suffer more frequently from acute cellular and also late cellular rejection. However, 5-year patient survival rates after LT of 80-85% is better than for most other indications. Recurrent PBC is reported in a range from 14% up to 42% after LT but in contrast to other autoimmune diseases graft loss due to recurrent disease is not a major issue. The type of immunosuppression after LT was found to be associated with the incidence of recurrence but since mediate-term impact on overall and graft survival is negligible, tacrolimus-based regimens remain standard at most centers. Observational studies suggest that long-term administration of UDCA following LT has a beneficial effect on recurrence of PBC. Therefore biomarkers after LT that may identify patients at risk for recurrence should be further explored to allows early medical intervention.

Current Status of Liver Transplantation for Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is an autoimmune cholestatic liver disease diagnosed with elevated alkaline phosphatase in the presence of antimitochondrial antibody. With the introduction and widespread use of ursodeoxycholic acid the proportion of PBC patients undergoing liver transplant (LT) has decreased. However, up to 40% of patients are ursodeoxycholic acid nonresponders and require second-line treatment or progress to end-stage liver disease requiring LT. Several scoring systems have been developed and validated to assess treatment response and transplant-free survival in patients. Although PBC is a favorable indication for LT, recurrence of PBC may occur and requires biopsy for diagnosis.

Natural History of Primary Biliary Cholangitis in the Ursodeoxycholic Acid Era: Role of Scoring Systems

Primary biliary cholangitis (PBC) is a chronic disease that progresses to end-stage liver disease. Ursodeoxycholic acid (UDCA), the standard treatment for PBC for several decades, is associated with improved survival without liver transplantation. Approximately 40% of patients do not respond to UDCA. Because of disease variability, several prognostic models exist that incorporate various factors including biochemical response to UDCA. Useful for patient care and counseling as well as risk stratification for research and clinical trials, the role of these models in the pre-UDCA and UDCA eras is discussed.

Risk stratification and prognostic modelling in primary biliary cholangitis

Primary biliary cholangitis (PBC) is a slowly progressive chronic cholestatic liver disease that, in a subgroup of patients, may result in liver failure or death. The definition of specific risk profiles, i.e. risk stratification, is of critical importance for the identification of these subgroups and thereby the targeting of care. Over the last few years large multicentre cohort studies have improved our knowledge regarding factors associated with progressive disease. Stratification based on biochemical response to ursodoxycholic acid provides a readily available measure to identify groups that might benefit from additional therapies to further improve prognosis. In addition, serum total bilirubin and alkaline phosphatase are now considered the most robustly validated biomarkers of long-term outcome in PBC and are used as endpoints in clinical trials. The GLOBE score and UK-PBC risk score enable us to quantify the risk of future events for the individual patient, allowing more individualized risk prediction. In this review, we discuss both established prognostic factors and newly developed tools to estimate prognosis in PBC, highlighting their strengths, limitations and applicability in clinical practice.

Improving prognosis in primary biliary cholangitis - Therapeutic options and strategy

Overall survival in primary biliary cholangitis is diminished. As patients are often asymptomatic, the disease may silently progress towards cirrhosis and liver failure. Timely diagnosis and effective treatment options are of vital importance to improve the prognosis of affected patients. Ursodeoxycholic acid is the standard of care first-line therapy and is associated with a reduced risk of liver transplantation and death. Treatment with UDCA is relevant for all patients, irrespective of disease stage or biochemical response. In case of incomplete biochemical response according to internationally accepted criteria, second-line treatment should be considered to improve long-term prognosis. Ursodeoxycholic acid has been the only accepted treatment for PBC during the last decades. Recent research, however, has identified a number of new therapeutic targets and agents, including obeticholic acid, fibrates and budesonide. While these agents all qualify as potentially beneficial second-line treatment, obeticholic acid is currently the only drug specifically approved for the treatment of PBC. Although long-term follow-up studies for these agents are mostly lacking, improvement of biochemical surrogate markers of clinical outcome induced by these drugs suggests a therapeutic benefit. The authors of this review aim to provide a summary of the results of previous and current studies evaluating medical treatments, and propose a treatment strategy based on the evidence available today.

Increased Waitlist Mortality and Lower Rate for Liver Transplantation in Hispanic Patients With Primary Biliary Cholangitis

BACKGROUND & AIMS

Data on the differences in ethnicity and race among patients with primary biliary cholangitis (PBC) awaiting liver transplantation (LT) are limited. We evaluated liver transplant waitlist trends and outcomes based on ethnicity and race in patients with PBC in the United States.

METHODS

Using the United Network for Organ Sharing (UNOS) registry, we collected data on patients with PBC on the liver transplant waitlist, and performed analysis with a focus on ethnicity and race-based variations clinical manifestations, waitlist mortality and LT rates from 2000 to 2014. Outcomes were adjusted for demographics, complications of portal hypertension, and Model for End-stage Liver Disease score at time of waitlist registration.

RESULTS

Although the number of white PBC waitlist registrants and additions decreased from 2000 to 2014, there were no significant changes in the number of Hispanic PBC waitlist registrants and additions each year. The proportion of Hispanic patients with PBC on the liver transplant waitlist increased from 10.7% in 2000 to 19.3% in 2014. Hispanics had the highest percentage of waitlist deaths (20.8%) of any ethnicity or race evaluated. After adjusting for demographic and clinical characteristics, Hispanic patients with PBC had the lowest overall rate for undergoing LT (adjusted hazard ratio, 0.71; 95% CI, 0. 60-0.83; P < .001) and a significantly higher risk of death while on the waitlist, compared to whites (adjusted hazard ratio, 1.41; 95% CI, 1.15-1.74; P < .001). Furthermore, Hispanic patients with PBC had the highest proportion of waitlist removals due to clinical deterioration.

CONCLUSIONS

In an analysis of data from UNOS registry focusing on outcomes, we observed differences in rates of LT and liver transplant waitlist mortality of Hispanic patients compared with white patients with PBC. Further studies are needed to improve our understanding of ethnicity and race-based differences in progression of PBC.

Geoepidemiology and changing mortality in primary biliary cholangitis

Primary biliary cholangitis (PBC), formerly called primary biliary cirrhosis, is a chronic cholestatic disease characterized by an autoimmune-mediated destruction of small and medium-sized intrahepatic bile ducts. Originally PBC was considered to be rare and almost invariably fatal, mainly because the diagnosis was made in patients presenting with advanced symptomatic disease (jaundice and decompensated cirrhosis). However, the development of a reproducible indirect immunofluorescence assay for antimitochondrial antibody made it possible to diagnose the disease at an earlier stage, and introduction of ursodeoxycholic acid therapy as the first-line therapy for PBC drastically changed PBC-related mortality. At present, patients with an early histological stage have survival rates similar to those of an age- and sex-matched control population. Although 30% of patients treated with ursodeoxycholic acid may exhibit incomplete responses, obeticholic acid and drugs currently in development are expected to be effective for these patients and improve outcomes. Meanwhile, more etiology and immunopathology studies using new technologies and novel animal models are needed to dissect variances of clinical course, treatment response, and outcome in each patient with PBC. Precision medicine that is individualized for each patient on the basis of the cause identified is eagerly awaited.