Delayed introduction of reduced-dose tacrolimus, and renal function in liver transplantation: the 'ReSpECT' study

Management of long-term complications from immunosuppression

This review discusses long-term complications from immunosuppressants after liver transplantation and the management of these complications. Common complications of calcineurin inhibitors include nephrotoxicity and metabolic diseases. Nephrotoxicity can be managed by targeting a lower drug level and/or adding an immunosuppressant of a different class. Metabolic disorders can be managed by treating the underlying condition and targeting a lower drug level. Gastrointestinal adverse effects and myelosuppression are common complications of antimetabolites that are initially managed with dose reduction or discontinuation if adverse events persist. Mammalian targets of rapamycin inhibitors are associated with myelosuppression, proteinuria, impaired wound healing, and stomatitis, which may require dose reduction or discontinuation. Induction agents and agents used for steroid-refractory rejection or antibody-mediated rejection are reviewed. Other rare complications of immunosuppressants are discussed as well.

Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

Bridging the critically ill patient with acute to chronic liver failure to liver transplantation

Liver transplantation (LT) has emerged as an effective therapy for severe forms of acute-on-chronic liver failure (ACLF), an entity characterized by the development of multiorgan failure and high short-term mortality. The aim of critical care management of ACLF patients is to rapidly treat precipitating events and aggressively support failing organs to ensure that patients may successfully undergo LT or, less frequently, recover. Malnutrition and sarcopenia are frequently present, adversely impacting the prognosis of these patients. Management of critical care patients with ACLF is complex and requires the participation of different specialties. Once the patient is stabilized, a rapid evaluation for salvage LT should be performed because the time window for LT is often narrow. The development of sepsis and prolonged organ support may preclude LT or diminish its chances of success. The current review describes strategies to bridge severe ACLF patients to LT, highlights the minimal evaluation required for listing and the currently suggested contraindications to proceed with LT, and addresses different aspects of management during the perioperative and early posttransplant period.

Post Liver Transplant Renal Dysfunction-Evaluation, Management and Immunosuppressive Practice

Liver transplantation (LT) is an effective and lifesaving treatment for patients with end-stage liver disease and hepatocellular carcinoma. Significant improvement in intermediate and long-term survival has been possible due to advancements in immunosuppressive therapy, perioperative care, and surgical techniques. Despite these advances, metabolic complications, including diabetes mellitus, cardiovascular diseases, malignancies, and renal dysfunction, are challenging issues after LT. Acute kidney injury (AKI) and chronic kidney disease (CKD) after LT are common and result in significant morbidity and mortality. Early diagnosis of kidney injury after LT is challenging, and no technique has yet proven effective in prediction of renal dysfunction. The methods for assessing renal function range from formulas that predict glomerular filtration rate to non-invasive biomarkers. The universal adoption of the model for end-stage liver disease has a direct impact on the incidence of peri-transplant AKI and development of CKD in the long-term. Post-LT renal dysfunction is multifactorial and is usually a result of pre-transplantation comorbidities, occurrence of renal dysfunction on the waiting list, perioperative events, and post-transplant nephrotoxic immunosuppressive medication use. Early identification of patients at risk for renal dysfunction and adoption of preventive measures are crucial in the pre-transplant period. No data are currently available to suggest a surgical technique that reliably demonstrates renal protection. Nephroprotective strategies during LT follow accepted surgical practice guidelines, such as maintenance of intravascular volume and mean arterial pressure. The management of kidney disease following LT is challenging, as by the time the serum creatinine is significantly elevated, few interventions impact the course of progression. Early nephroprotective measures are strongly advised and they mostly center on delaying the administration of calcineurin inhibitors (CNIs) during the initial postoperative period, lowering CNI dosage and combining CNI with mycophenolate mofetil and everolimus. The reasons for renal failure following LT, the techniques used to diagnose it, and the therapies designed to preserve renal function both immediately and late after LT are all critically evaluated in this review.

Evaluation of the efficacy and safety of conversion from the tacrolimus capsule to tablet in stable liver transplant recipients with maintenance therapy: a 24-week, open-label, single-center, phase IV exploratory clinical study

Purpose

The tablet form of tacrolimus is more convenient for drug ingestion than the capsule form. We examined the efficacy and safety of tacrolimus tablets and a satisfaction survey after formula conversion in liver transplant (LT) recipients.

Methods

This study was an open-label, prospective clinical trial for tacrolimus formula 1:1 conversion from capsule to tablet in 41 adult LT recipients with tacrolimus maintenance therapy of more than 1 month. The primary endpoint was incidence of biopsy-proven acute rejection (BPAR) within 24 weeks. Surveys 1 week before and 4 weeks after formula conversion were conducted for total daily dose of medication, number, scale of discomfort and satisfaction.

Results

The overall incidence of BPAR was 0% and there was no graft loss or patient death. The incidence of adverse effects was 34.1% (n = 14) after formula conversion. The most common severe adverse effect was abnormal liver function test (n = 5): biliary complications (n = 4) and alcoholic recidivism (n = 1). Total daily dose and number of tacrolimus doses were significantly lower after formula conversion (P < 0.05) without changes in trough level. According to survey analysis, there was no significant difference in discomfort and satisfaction scales from capsule to tablet conversion (P < 0.05).

Conclusion

The present study suggests that the new tablet formula can be a useful treatment option to maintain a consistent level of tacrolimus with a lower total daily dose and number in adult LT recipients.

Impact of Sirolimus versus Mycophenolate Mofetil on Kidney Function after Calcineurin Inhibitor Dose Reduction in Liver Transplant Recipients

Impaired kidney function is associated with increased morbidity and mortality in patients undergoing liver transplantation. Although immunosuppressants are essential in these patients, they impair kidney function. This study aimed to compare adverse kidney outcomes between patients treated with a reduced dose of tacrolimus (calcineurin inhibitor) plus sirolimus or mycophenolate mofetil (MMF) in the liver transplant center at Kaohsiung Chang Gung Memorial Hospital between April 2011 and December 2017. Propensity score matching was used to identify 232 patients. The risk of adverse kidney outcomes was estimated using Cox proportional hazards regression, and changes in kidney function over time were analyzed using linear mixed modeling. Acute kidney disease risks in this study cohort were not significantly different for the two immunosuppressants (aHR 1.04; 95% CI: 0.70-1.55, p = 0.8328). However, sirolimus use was significantly associated with a higher risk of estimated glomerular filtration rate decline > 30% than MMF (aHR, 2.09; 95% CI: 1.33-3.28; p = 0.0014). Our results demonstrate that sirolimus use may have worsened long-term kidney outcomes compared to MMF. Close monitoring of kidney function, dose adjustment, and timely transition to MMF is necessary for LT patients receiving sirolimus.

Chronic Kidney Disease After Liver Transplantation

Chronic kidney disease among liver transplant recipients is common and associated with an increased mortality risk. Several risk factors and causes for the development of chronic kidney disease have been identified. They can be divided into perioperative factors, such as unresolved acute kidney injury; donor-related factors, such as the use of extended criteria liver allografts; and recipient-related factors, such as the use of calcineurin inhibitors and the presence of metabolic syndrome, diabetes, and obesity. There is a bimodal progression, more prominent during the initial post-transplant months, followed by a gradual but progressive decline over the subsequent years. Management strategies to prevent and treat chronic kidney disease in the general population can be reasonably applied to the liver transplant population and include addressing comorbidities such as hypertension and diabetes. Strategies to minimize or withdraw calcineurin inhibitors from the immunosuppressive regimen can slow progression of kidney dysfunction. Patients with advanced chronic kidney disease should be considered for kidney transplantation due to its survival advantage. Allocation policy in the United States confers safety-net allocation priority for liver transplant recipients who develop advanced chronic kidney disease within the first year of liver transplantation.

Immunosuppression Monitoring-What Clinician Needs to Know?

The liver is well known for its immunotolerance, but rejection without immunosuppression is frequently encountered post liver transplantation, especially in humans.1 Indeed, the amount of immunosuppression required post liver transplant is less compared to other organ transplants like kidney, heart, and intestine.2 Reports of successful weaning of immunosuppression have been reported but are not practiced for fear of unwanted alloimmune response leading to rejection. Life-long immunosuppression is needed in most patients for graft survival but is associated with side effects like renal dysfunction, metabolic abnormalities, or risk of de novo malignancies. Also, the appropriate dose of immunosuppression to achieve adequate graft function and prevention of toxicities is very important. One shoe does not fit all. There are significant individual variations in response and side effect profile. Also, the level of immunosuppression varies with the underlying liver disease like autoimmune disease requires higher immunosuppression. Thus, monitoring the adequate immunosuppression with the minimization of drug toxicity is imperative post-transplant. Unfortunately, the current methods for immunosuppression monitoring rely on testing the immunosuppressive drug levels rather than the immune system activity. We have discussed the concept of alloreactivity, available methods of immunosuppression and drug monitoring and investigational methods in this review.

Essentials of Liver Transplantation in the Setting of Acute Kidney Injury and Chronic Kidney Disease

Kidney dysfunction is common among liver transplant candidates with decompensated cirrhosis and has a major impact on pre- and post-liver transplant survival. Updated definitions of acute kidney injury and criteria for the diagnosis of hepatorenal syndrome allow for early recognition and intervention, including early initiation of vasoconstrictor therapy for hepatorenal syndrome. The rise of the metabolic syndrome and nonalcoholic fatty liver disease as a cause of cirrhosis has coincided with an increase in intrinsic chronic kidney disease recognized in transplant candidates and recipients. Ultimately, the ability to accurately assess kidney function and associated risk is essential to decision-making in the context of transplantation, including selection of candidates for simultaneous liver and kidney transplantation.

EnGraft: a multicentre, open-label, randomised, two-arm, superiority study protocol to assess bioavailability and practicability of Envarsus® versus Advagraf™ in liver transplant recipients

BACKGROUND

Graft rejection and chronic CNI toxicity remain obstacles to organ transplant success. Current formulations of tacrolimus, such as Prograf® and Advagraf™, exhibit limitations in terms of pharmacokinetics and tolerability, related in part to suboptimal bioavailability. As dosing non-compliance can result in graft rejection, the once daily formulation of tacrolimus, Advagraf™, was developed (vs 2x/day Prograf®). Benefits of Advagraf™ are counterbalanced by delayed achievement of therapeutic trough levels and need for up to 50% higher doses to maintain Prograf®-equivalent troughs. Envarsus® is also a prolonged-release once-daily tacrolimus formulation, developed using MeltDose™ drug-delivery technology to increase drug bioavailability; improved bioavailability results in low patient drug absorption variability and less pronounced peak-to-trough fluctuations. In phase III de novo kidney transplant studies, Envarsus® proved non-inferior to twice-daily tacrolimus; however, no phase IV studies show superiority of Envarsus® vs Advagraf™ in de novo liver transplant (LTx) recipients.

METHODS

The EnGraft compares bioavailability and tests superiority of Envarsus® (test arm) versus Advagraf™ (comparator arm) in de novo LTx recipients. A total of 268 patients from 15 German transplant centres will be randomised 1:1 within 14 days post-LTx. The primary endpoint is dose-normalised trough level (C/D ratio) measured 12 weeks after randomisation. Secondary endpoints include the number of dose adjustments, time to reach first defined trough level and incidence of graft rejections. Additionally, clinical and laboratory parameters will be assessed over a 3-year period.

DISCUSSION

C/D ratio is an estimate for tacrolimus bioavailability. Improving bioavailability and increasing C/D ratio using Envarsus could reduce renal dysfunction and other tacrolimus-related toxicities; previous trials have shown that a higher C/D ratio (i.e. slower tacrolimus metabolism) is not only associated with improved renal function but also linked to reduced neurotoxic side effects. A higher C/D ratio could improve clinical outcomes for LTx recipients; EnGraft has begun, with one third of patients recruited by January 2022.

TRIAL REGISTRATION

This trial has been registered (4 May 2020) in the EU Clinical Trials Register, EudraCT-Nummer: 2020-000796-20. Additionally, this trial has been registered (22 January 2021) at ClinicalTrials.gov: NCT04720326. The trial received a favourable opinion from the concerned lead ethics committee at the University of Regensburg, under the reference 20-1842-112.

Three-year results of renal function in liver transplant recipients on low-dose sirolimus and tacrolimus: a multicenter, randomized, controlled trial

The aim of this study was to investigate whether the combination of low-dose sirolimus (SRL) and low-dose extended-release tacrolimus (TAC) compared to normal-dose extended-release TAC results in a difference in the renal function and comparable rates of rejection, graft and patient survival at 36 months after transplantation. This study was an open-label, multicenter randomized, controlled trial. Patients were randomized to once-daily normal-dose extended-release TAC (control group) or once-daily combination therapy of SRL and low-dose extended-release TAC (interventional group). The primary endpoint was the cumulative incidence of chronic kidney disease (CKD) defined as grade ≥3 (estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2) at 36 months after transplantation. In total, 196 patients were included. CKD at 36 months was not different between the control and interventional group (50.8%, 95% CI: 39.7%-59.9%) vs. 43.7%, 95% CI: 32.8%-52.8%). Only at 6 months after transplantation, the eGFR was higher in the interventional group compared to the control group (mean eGFR 73.1±15 vs. 67.6±16 mL/min/1.73 m2, p=0.02) in the intention-to-treat population. No differences in the secondary endpoints and the number of serious adverse events were found between the groups. Once daily low-dose SRL combined with low-dose extended-release TAC does ultimately not provide less CKD grade ≥3 at 36 months compared to normal-dose extended-release TAC.

Liver transplantation for non-alcoholic fatty liver disease: indications and post-transplant management

Non-alcoholic fatty liver disease (NAFLD) is currently the fastest growing indication to liver transplantation (LT) in Western Countries, both for end stage liver disease and hepatocellular carcinoma. NAFLD/non-alcoholic steatohepatitis (NASH) is often expression of a systemic metabolic syndrome; therefore, NAFLD/NASH patients require a multidisciplinary approach for a proper pre-surgical evaluation, which is important to achieve a post-transplant outcome comparable to that of other indications to LT. NAFLD/NASH patients are also at higher risk of post-transplant cardiovascular events, diabetes, dyslipidemia, obesity, renal impairment and recurrent NASH. Lifestyle modifications, included diet and physical activity, are key to improve survival and quality of life after transplantation. A tailored immunosuppressive regimen may be proposed in selected patients. Development of new drugs for the treatment of recurrent NASH is awaited.

Immunosuppressive Drugs in Liver Transplant: An Insight

Liver transplantation (LT) is the standard of care for end-stage liver failure and hepatocellular carcinoma. Over the years, immunosuppression regimens have improved, resulting in enhanced graft and patient survival. At present, the side effects of immunosuppressive agents are a significant threat to post-LT quality of life and long-term outcome. The role of personalized immunosuppression is to reach a delicate balance between optimal immunosuppression and minimal side effects. Today, immunosuppression in LT is more of an art than a science. There are no validated markers for overimmunosuppression and underimmunosuppression, only a few drugs have therapeutic drug monitoring and immunosuppression regimens vary from center to center. The immunosuppressive agents are broadly classified into biological agents and pharmacological agents. Most regimens use multiple agents with different modes of action to reduce the dosage and minimize the toxicities. The calcineurin inhibitor (CNI)-related toxicities are reduced by antibody induction or using mTOR inhibitor/antimetabolites as CNI sparing or CNI minimization strategies. Post-liver transplant immunosuppression has an intensive phase in the first three months when alloreactivity is high, followed by a maintenance phase when immunosuppression minimization protocols are implemented. Over time some patients achieve "tolerance," defined as the successful stopping of immunosuppression with good graft function and no indication of rejection. Cell-based therapy using immune cells with tolerogenic potential is the future and may permit complete withdrawal of immunosuppressive agents.

Renal histopathological lesions after liver transplantation: What can we find besides calcineurin inhibitor-induced nephrotoxicity?

Background

Chronic kidney disease (CKD) is a common complication after liver transplantation and is traditionally considered to be secondary to calcineurin inhibitors (CNIs). However, several studies have reported that the etiology of CKD after liver transplantation is broad and may only be assessed accurately by renal biopsy. The current study aimed to explore the usefulness of renal biopsies in managing CKD after liver transplantation in daily clinical practice.

Method

This retrospective analysis enrolled all post-liver transplantation patients who had a renal biopsy in a single center from July 2018 to February 2021.

Results

Fourteen renal biopsies were retrieved for review from 14 patients at a median of 35.7 (minimum-maximum: 2.80–134.73) months following liver transplantation. The male-to-female ratio was 13:1 (age range, 31–75 years). The histomorphological alterations were varied. The predominant glomerular histomorphological changes included focal segmental glomerular sclerosis (FSGS) (n = 4), diabetic glomerulopathy (n = 4), and membranoproliferative glomerulonephritis (n = 4). Thirteen (92.9%) patients had renal arteriolar sclerosis. Immune complex nephritis was present in six patients, of whom only two had abnormal serum immunological indicators. Despite interstitial fibrosis and tubular atrophy being present in all the patients, only six (42.9%) presented with severe interstitial injury. No major renal biopsy-related complications occurred. After a mean follow-up of 11.8 months (range: 1.2–29.8), three patients progressed to end-stage renal disease (ESRD).

Conclusion

The etiology of CKD after liver transplantation might be more complex than originally thought and should not be diagnosed simply as calcineurin inhibitors(CNI)-related nephropathy. Renal biopsy plays a potentially important role in the diagnosis and treatment of CKD after liver transplantation and might not be fully substituted by urine or blood tests. It may help avoid unnecessary changes to the immunosuppressants and inadequate treatment of primary diseases.

Renal function after liver transplantation: Real-world experience with basiliximab induction and delayed reduced-dose tacrolimus

BACKGROUND

Routine use of delayed reduced-dose calcineurin-inhibitor treatment with induction immunosuppression in liver transplantation to minimize post-operative kidney injury is still scarce.

AIM

To evaluate real-world experience of basiliximab induction with delayed reduced-dose tacrolimus.

METHODS

In a retrospective cohort study, kidney function was evaluated pre- and postoperatively by measured glomerular filtration rate (mGFR). Adult patients undergoing liver transplantation between 2000 and 2017 were divided into a conventional treatment group (immediate-introduction of tacrolimus, target trough levels 10-15 ng/mL, and corticosteroids, n = 203) and a revised treatment group (basiliximab induction, reduced-dose tacrolimus, target through levels 5-8 ng/mL, delayed until day three, and mycophenolate mofetil 2000 mg/day, n = 343).

RESULTS

Mean mGFR was similar between groups at wait-listing (85.3 vs 84.1 ml/min/1.73m², p = 0.60), but higher in the revised treatment group at 3 (56.8 vs 63.4 ml/min/1.73m², p = 0.004) and 12 months post-transplant (60.9 vs 69.7 ml/min/1.73m², p<0.001); this difference remained after correcting for multiple confounders and was independent of pre-transplant mGFR. In the revised treatment group, biopsy proven acute rejection rate was lower (38% vs. 21%, p<0.001), and graft-survival better (p = 0.01).

CONCLUSION

Basiliximab induction with delayed reduced-dose tacrolimus is associated with less kidney injury when compared to standard-dose tacrolimus, without increased risk of rejection, graft loss or death.

Chronic Kidney Disease After Liver Transplantation

Improved survival after liver transplantation has led to an aging cohort of recipients at risk of renal dysfunction. The etiology of renal dysfunction is typically multifactorial; calcineurin inhibitors nephrotoxicity, pretransplant renal dysfunction, and perioperative acute kidney injury are important risk factors. Metabolic complications such as hypertension, diabetes mellitus, and metabolic-associated fatty liver disease also contribute to the development of renal disease. Most LT recipients will eventually develop some degree of renal dysfunction. Criteria to select candidates for simultaneous liver and kidney transplantation have been established. Both delayed introduction of CNIs and renal-sparing immunosuppressive regimens may reduce progression of renal dysfunction.

[Kidney failure after liver transplantation]

One third of cirrhotic patients present impaired kidney function. It has multifactorial causes and has a harmful effect on patients' morbi-mortality before and after liver transplant. Kidney function does not improve in all patients after liver transplantation and liver-transplant recipients are at high risk of developing chronic kidney disease. Causes for renal dysfunction can be divided in three groups: preoperative, peroperative and postoperative factors. To date, there is no consensus for the modality of evaluation the risk for chronic kidney disease after liver transplantation, and for its prevention. In the present review, we describe the outcome of kidney function after liver transplantation, and the prognostic factors of chronic kidney disease to determine a risk stratification for each patient. Furthermore, we discuss therapeutic options to prevent kidney dysfunction in this setting, and highlight the indications of combined liver-kidney transplantation.

Effect of the response to preoperative treatment for hepatorenal syndrome on the outcome of recipients of living-donor liver transplantation

BACKGROUND

The effect of pretransplant hepatorenal syndrome (HRS) on the outcomes of living-donor liver transplantation (LDLT) recipients with special reference to the recovery of HRS before LDLT was investigated.

METHODS

The rate of HRS was 43.9% (125/285) among the cohort, and the subjects were divided into 3 groups: those without HRS (No-HRS group, n=160), those with HRS but recovered following pretransplant renal function restoration treatment (Responders group, n=55), and those with persistent HRS (Non-responders group, n=70).

RESULTS

While the 1-, 3-, and 5-year patient survival rates were comparable between those with and without HRS (89.6%, 84.7%, and 84.7% vs. 95.6%, 92.2%, and 87.5%), the cumulative incidence of the development of posttransplant chronic kidney disease (CKD) was significantly higher in those with HRS (p<0.001). In addition, there was a significant difference between Responders and Non-responders in the development of CKD (p=0.01). In the Cox regression model, Non-responders (p=0.032, HR 1.79 [95% C.I. 1.05-3.03]) and recipient age (p=0.014, HR 1.62 [95% C.I. 1.10-2.37]) were independent predictors for the development of CKD after LDLT.

CONCLUSION

LDLT is safe and effective for patients with HRS, and CKD progression could be reduced among those with HRS who responded to renal restoration treatment.

Biological therapies in patients with liver disease: are they really lifesavers?

INTRODUCTION

The liver plays a key role in the setting of immune tolerance. Targeting antigens for presentation by antigen-presenting cells in the liver can induce immune tolerance to either autoantigens from the liver itself or organs outside of the liver. Despite its non-conventional capacity for tolerance induction, the liver remains a target organ for autoimmune diseases. Whereas chronic inflammation and intra-hepatic immuno-suppressive microenvironment occurring during liver fibrosis lead to hepatocellular carcinoma. Monoclonal antibodies have revolutionized the therapeutic strategies of many autoimmune diseases and some cancers.

AREAS COVERED

We review data from literature regarding the safety and efficacy of biologics in treating hepatobiliary autoimmune diseases and primary liver cancers. Furthermore, we describe their potential use in the setting of liver transplants and their main immune-related liver adverse events.

EXPERT OPINION

Biological therapies have changed the natural history of main autoimmune diseases and solid cancers. Compared to other organs and disease settings, the liver lags behind in biologics and their applications. The development of novel diagnostic and therapeutic strategies based on the immunological and antigenic characteristics of the hepatobiliary system could reduce mortality and transplant rates linked to chronic liver diseases.

Post-liver transplantation chronic kidney disease is associated with increased cardiovascular disease risk and poor survival

Chronic kidney disease (CKD) is common following liver transplantation (LT). We aimed to investigate the frequency, risk factors, and impact of CKD on cardiovascular disease (CVD), graft, and patient survival. We analyzed 752 patients who received LT at the University of Alberta. Development of CKD was defined as eGFR <60 ml/min for greater than 3 months, intrinsic renal disease or presence of end-stage renal disease requiring renal replacement therapy. 240 patients were female (32%), and mean age at LT was 53 ± 11 years. CKD was diagnosed in 448 (60%) patients. On multivariable analysis, age (OR 1.3; P = 0.01), female sex (OR 3.3; P < 0.001), baseline eGFR (OR 0.83; P < 0.001), MELD (OR 1.03; P = 0.01), de novo metabolic syndrome (OR 2.3; P = 0.001), and acute kidney injury (OR 3.5; P < 0.001) were associated with CKD. A higher tacrolimus concentration to dose ratio was protective for CKD (OR 0.69; P < 0.001). CKD was associated with post-transplant CVD (26% vs. 16% P < 0.001), reduced graft (HR 1.4; P = 0.02), and patient survival (HR 1.3; P = 0.03). CKD is a frequent complication following LT and is associated with an increased risk of CVD and reduced graft and patient survival.

Strategies to Improve Immune Suppression Post-Liver Transplantation: A Review

Since the first liver transplantation operation (LT) in 1967 by Thomas Starzl, efforts to increase survival and prevent rejection have taken place. The development of calcineurin inhibitors (CNIs) in the 1980s led to a surge in survival post-transplantation, and since then, strategies to prevent graft loss and preserve long-term graft function have been prioritized. Allograft rejection is mediated by the host immune response to donor antigens. Prevention of rejection can be achieved through either immunosuppression or induction of tolerance. This leads to a clinical dilemma, as the choice of an immunosuppressive agent is not an easy task, with considerable patient and graft-related morbidities. On the other hand, the induction of graft tolerance remains a challenge. Despite the fact that the liver exhibits less rejection than any other transplanted organs, spontaneous graft tolerance is rare. Most immunosuppressive medications have been incriminated in renal, cardiovascular, and neurological complications, relapse of viral hepatitis, and recurrence of HCC and other cancers. Efforts to minimize immunosuppression are directed toward decreasing medication side effects, increasing cost effectiveness, and decreasing economic burden without increasing the risk of rejection. In this article, we will discuss recent advances in strategies for improving immunosuppression following liver transplantation.

Post-Liver Transplant Acute Kidney Injury

Acute kidney injury (AKI) is a common condition following liver transplantation (LT). It negatively impacts patient outcomes by increasing the chances of developing chronic kidney disease and reducing graft and patient survival rates. Multiple definitions of AKI have been proposed and used throughout the years, with the International Club of Ascites definition being the most widely now used for patients with cirrhosis. Multiple factors are associated with the development of post-LT AKI and can be categorized into pre-LT comorbidities, donor and recipient characteristics, operative factors, and post-LT factors. Many of these factors can be optimized in an attempt to minimize the risk of AKI occurring and to improve renal function if AKI is already present. A special consideration during the post-LT phase is needed for immunosuppression as certain immunosuppressive medications can be nephrotoxic. The calcineurin inhibitor tacrolimus (TAC) is the mainstay of immunosuppression but can result in AKI. Several strategies including use of the monoclonoal antibody basilixamab to allow for delayed initiation of tacrolimus therapy and minimization through combination and minimization or elimination of TAC through combination with mycophenolate mofetil or mammalian target of rapamycin inhibitors have been implemented to reverse and avoid AKI in the post-LT setting. Renal replacement therapy may ultimately be required to support patients until recovery of AKI after LT. Overall, by improving renal function in post-LT patients with AKI, outcomes can be improved.

Kidney Disease After Nonkidney Solid Organ Transplant

Nonkidney solid organ transplants (NKSOTs) are increasing in the United States with improving long-term allograft and patient survival. CKD is prevalent in patients with NKSOT and is associated with increased morbidity and mortality especially in those who progress to end-stage kidney disease. Calcineurin inhibitor nephrotoxicity is a main contributor to CKD after NKSOT, but other factors in the pretransplant, peritransplant, and post-transplant period can predispose to progressive kidney dysfunction. The management of CKD after NKSOT generally follows society guidelines for native kidney disease. Kidney-protective and calcineurin inhibitor-sparing immunosuppression has been explored in this population and warrants a discussion with transplant teams. Kidney transplantation in NKSOT recipients remains the kidney replacement therapy of choice for suitable candidates, as it provides a survival benefit over remaining on dialysis.

A meta-analysis of the cumulative incidence, risk factors, and clinical outcomes associated with chronic kidney disease after liver transplantation

Chronic kidney disease (CKD) remains a relatively common complication after liver transplantation (LT), and significantly impacts overall survival. We sought to assess the cumulative incidence, risk factors and mortality associated with post-LT CKD. CKD was defined as eGFR <60 ml/min/1.73 m² as estimated by the Modified Diet in Renal Disease (MDRD) formula. Single-arm meta-analysis was done to evaluate the cumulative incidence of CKD at 1-, 3-, and 5-year timepoints post-LT. Risk factors for CKD were evaluated using hazard ratios (HR). Twenty-one studies involving 44 383 patients were included. Cumulative incidence of stage 3-5 CKD was 31.44% (CI 0.182-0.447), 36.71% (CI 0.188-0.546), and 43.52% (CI 0.296-0.574) at 1, 3, and 5 years after LT, respectively. Stage 5 CKD cumulative incidence increased from 0.274% (CI 0.001-0.005) at 1 year to 2.06% (CI 0.009-0.045) at 5 years post-LT. Age, female sex, diabetes, and peri-operative acute kidney injury (AKI) were significant risk factors for CKD. Stage 4-5 CKD was associated with a decrease in overall survival (HR 3.23, 95% CI 1.74-5.98, P < 0.01). CKD after LT is relatively common, and is associated with significantly reduced overall survival. Identification of patients at high risk of developing CKD allows physicians to prophylactically use renal-sparing immunosuppression which may be crucial in achieving desirable clinical outcomes.

Kidney Failure after Liver Transplantation

One-third of patients with cirrhosis present kidney failure (AKI and CKD). It has multifactorial causes and a harmful effect on morbidity and mortality before and after liver transplantation. Kidney function does not improve in all patients after liver transplantation, and liver transplant recipients are at a high risk of developing chronic kidney disease. The causes of renal dysfunction can be divided into three groups: pre-operative, perioperative and post-operative factors. To date, there is no consensus on the modality to evaluate the risk of chronic kidney disease after liver transplantation, or for its prevention. In this narrative review, we describe the outcome of kidney function after liver transplantation, and the prognostic factors of chronic kidney disease in order to establish a risk categorization for each patient. Furthermore, we discuss therapeutic options to prevent kidney dysfunction in this context, and highlight the indications of combined liver–kidney transplantation.

Black Race Is Associated With Higher Rates of Early-Onset End-Stage Renal Disease and Increased Mortality Following Liver Transplantation

Black race is a risk factor for end-stage renal disease (ESRD). Racial disparities in the risks of early and long-term renal complications after liver transplantation (LT) have not been systematically studied. This study evaluated racial differences in the natural history of acute and chronic renal insufficiency after LT. This was a retrospective single-center cohort study of 763 non-Hispanic White and 181 Black LT recipients between 2008 and 2017. Black race was investigated as an independent predictor of the following outcomes: (1) receipt and duration of early post-LT hemodialysis and (2) time to post-LT ESRD. The interaction of race and post-LT ESRD on survival was also studied. Black recipients had higher rates of pre-LT hypertension (P < 0.001), but diabetes mellitus and renal function before LT were not different by race (all P > 0.05). Overall, 15.2% of patients required early hemodialysis immediately after LT with no difference by race (covariate-adjusted odds ratio, 0.89; P = 0.71). Early dialysis discontinuation was lower among Black recipients (covariate-adjusted hazard ratio [aHR], 0.47; P = 0.02), whereas their rate of post-LT ESRD was higher (aHR, 1.91; P = 0.005). Post-LT survival after ESRD was markedly worse for Black (aHR, 11.18; P < 0.001) versus White recipients (aHR, 5.83; P < 0.001; interaction P = 0.08). Although Black and White LT recipients had comparable pretransplant renal function, post-LT renal outcomes differed considerably, and the impact of ESRD on post-LT survival was greater for Black recipients. This study highlights the need for an individualized approach to post-LT management to improve outcomes for all patients.

Induction Therapy With Antithymocyte Globulin and Delayed Calcineurin Inhibitor Initiation for Renal Protection in Liver Transplantation: A Multicenter Randomized Controlled Phase II-B Trial

BACKGROUND

Calcineurin inhibitor (CNI) based immunosuppression in liver transplantation (LTx) is associated with acute and chronic deterioration of kidney function. Delaying CNI initiation by using induction rabbit anti-thymocyte globulin (rATG) may provide kidneys with adequate time to recover from a perioperative insult reducing the risk of early post-LTx renal deterioration.

METHODS

This was an open-label, multicenter, randomized controlled clinical trial comparing use of induction rATG with delayed CNI initiation (day-10) against upfront CNI commencement (SOC; standard of care) in those patients deemed at standard risk of postoperative renal dysfunction following LTx. The primary end point was change in (delta) creatinine from baseline to month-12.

RESULTS

Fifty-five patients were enrolled in each study arm. Mean Tacrolimus levels remained comparable in both groups from day-10 throughout the study period. A significant difference in delta creatinine was observed between rATG and SOC groups at 9-months (p=0.03) but not at month-12 (p=0.05). eGFR levels remained comparable between cohorts at all time points. Rates of biopsy-proven acute rejection at 1-year were similar between groups (16.3 vs 12.7%, p= 0.58). rATG showed no significant adverse effects. Survival at 12-months was comparable between groups (p= 0.48).

CONCLUSIONS

Although the use of induction rATG and concurrent CNI deferral in this study did not demonstrate a significant difference in delta creatinine at 1 year, these results indicate a potential role for rATG in preserving early kidney function, especially when considered with CNI deferral beyond 10 days and/or lower target Tacrolimus levels, with acceptable safety and treatment efficacy.

Liver Transplantation in Acute-on-chronic Liver Failure

Liver transplantation (LT) has revolutionized outcomes for cirrhotic patients. Current liver allocation policies dictate patients with highest short-term mortality receive the highest priority, thus, several patients become increasingly ill on the waitlist. Given cirrhosis is a progressive disease, it can be complicated by the occurrence of acute-on-chronic liver failure (ACLF), a syndrome defined by an acute deterioration of liver function associated with extrahepatic organ failures requiring intensive care support and a high short-term mortality. Successfully bridging to transplant includes accurate prognostication and prioritization of ACLF patients awaiting LT, optimizing intensive care support pre-LT, and tailoring immunosuppressive and anti-infective therapies post-LT. Furthermore, predicting futility (too sick to undergo LT) in ACLF is challenging. In this review, we summarize the role of LT in ACLF specifically highlighting (a) current prognostic scores in ACLF, (b) critical care management of the ACLF patient awaiting LT, (c) donor issues to consider in transplant in ACLF, and (d) exploring of recent post-LT outcomes in ACLF and potential opportunities to improve outcomes including current care gaps and unmet research needs.

Long-term, Prolonged-release Tacrolimus-based Immunosuppression in De Novo Liver Transplant Recipients: 5-year Prospective Follow-up of Patients in the DIAMOND Study

Background

Immunosuppression with calcineurin inhibitors (CNIs) is reportedly associated with risk of renal impairment in liver transplant recipients. It is believed that this can be mitigated by decreasing initial exposure to CNIs or delaying CNI introduction until 3-4 d posttransplantation. The ADVAGRAF studied in combination with mycophenolate mofetil and basiliximab in liver transplantation (DIAMOND) trial evaluated different administration strategies for prolonged-release tacrolimus (PR-T).

Methods

DIAMOND was a 24-wk, open-label, phase 3b trial in de novo liver transplant recipients randomized to: PR-T 0.2 mg/kg/d (Arm 1); PR-T 0.15-0.175 mg/kg/d plus basiliximab (Arm 2); or PR-T 0.2 mg/kg/d delayed until day 5 posttransplant plus basiliximab (Arm 3). In a 5-y follow-up, patients were maintained on an immunosuppressive regimen according to standard clinical practice (NCT02057484). Primary endpoint: graft survival (Kaplan-Meier analysis).

Results

Follow-up study included 856 patients. Overall graft survival was 84.6% and 73.5% at 1 and 5 y post transplant, respectively. Five-year rates for Arms 1, 2, and 3 were 74.7%, 71.5%, and 74.5%, respectively. At 5 y, death-censored graft survival in the entire cohort was 74.7%. Overall graft survival in patients remaining on PR-T for ≥30 d was 79.1%. Graft survival in patients who remained on PR-T at 5 y was 87.3%. Patient survival was 86.6% at 1 y and 76.3% at 5 y, with survival rates similar in the 3 treatment arms at 5 y. Estimated glomerular filtration rate at the end of the 24-wk initial study and 5 y posttransplant was 62.1 and 61.5 mL/min/1.73 m², respectively, and was similar between the 3 treatment arms at 5 y. Overall, 18 (2.9%) patients had ≥1 adverse drug reaction, considered possibly related to PR-T in 6 patients.

Conclusions

In the DIAMOND study patient cohort, renal function, graft survival, and patient survival were similar between treatment arms at 5 y posttransplant.

Evaluation of Longitudinal Exposure to Tacrolimus as a Risk Factor of Chronic Kidney Disease Occurrence Within the First-year Post-Liver Transplantation

BACKGROUND

Renal failure is predictive of mortality in the early postliver-transplantation period and calcineurin inhibitors toxicity is a main challenge. Our aim is to assess the impact of longitudinal tacrolimus exposure (TLE) and other variables on chronic kidney disease (CKD)-free 1-year-survival.

METHODS

Retrospective data of consecutive patients transplanted between 2011 and 2016 and treated with tacrolimus were collected. TLE and all relevant pre- and post-liver transplantation (LT) predictive factors of CKD were tested and included in a time-to-event model. CKD was defined by repeated estimated glomerular filtration rate (eGFR) values below 60 mL/min/1.73m2 at least for the last 3 months before M12 post-LT.

RESULTS

Data from 180 patients were analyzed. CKD-free survival was 74.5% and was not associated with TLE. Pre-LT acute kidney injury (AKI) and eGFR at 1-month post-LT (eGFRM1) <60 mL/min/1.73m2 were significant predictors of CKD. By distinguishing 2 situations within AKI (ie, with or without hepatorenal syndrome [HRS]), only HRS-AKI remained associated to CKD. HRS-AKI and eGFRM1 <60 mL/min/1.73m2 increased the risk of CKD (hazard ratio, 2.5; 95% confidence interval, 1.2-4.9; hazard ratio, 4.8; 95% confidence interval, 2.6-8.8, respectively).

CONCLUSIONS

In our study, TLE, unlike HRS-AKI and eGFRM1, was not predictive of CKD-free survival at 1-year post-LT. Our results once again question the reversibility of HRS-AKI.

Therapeutic drug monitoring of immunosuppressive drugs in hepatology and gastroenterology

Immunosuppressive drugs have been key to the success of liver transplantation and are essential components of the treatment of inflammatory bowel disease (IBD) and autoimmune hepatitis (AIH). For many but not all immunosuppressants, therapeutic drug monitoring (TDM) is recommended to guide therapy. In this article, the rationale and evidence for TDM of tacrolimus, mycophenolic acid, the mammalian target of rapamycin inhibitors, and azathioprine in liver transplantation, IBD, and AIH is reviewed. New developments, including algorithm-based/computer-assisted immunosuppressant dosing, measurement of immunosuppressants in alternative matrices for whole blood, and pharmacodynamic monitoring of these agents is discussed. It is expected that these novel techniques will be incorporate into the standard TDM in the next few years.

Basiliximab With Delayed Tacrolimus Improves Short-Term Renal Outcomes Post-Liver Transplantation-a Real-World Experience

BACKGROUND

Acute kidney injury (AKI) is common after liver transplantation (LT). Induction with interleukin-2 receptor antagonists is often used as a "renal-sparing" strategy. The aim of this study was to assess this approach in a real-world setting in an LT center.

METHODS

A retrospective cohort analysis of LTs between 2011 and 2018 was performed to assess the impact of a renal-sparing strategy using basiliximab in conjunction with mycophenolate mofetil and corticosteroids from day 0 post-LT along with delayed introduction of tacrolimus. This was compared with a group receiving tacrolimus, mycophenolate mofetil, and corticosteroids from the outset.

RESULTS

The renal-sparing regimen was associated with significantly lower incidence of all-stage AKI at day 7 post-LT (36% vs 55%, P = .006) and less decline in renal function at 3 months (39% vs 57%, P = .01). No further significant differences in renal outcomes were observed at other time points on follow-up to 1 year post-LT. There was no significant difference in the incidence of acute cellular rejection, inpatient length of stay or graft survival. The decision to adopt a renal-sparing regimen was predominantly made on a clinically reactive basis within the first 24 hours post-LT in 77%, and was preordained in 23%. Cost-effectiveness analysis did not find evidence of a significant cost saving when using a renal-sparing strategy.

CONCLUSION

This study provides real-world analysis of the use of a renal-sparing immunosuppression regimen in LT. Although improvements in incidence of AKI in the short term were demonstrated, this did not translate to cost savings or improved renal outcomes after 3 months.

Early tacrolimus exposure does not impact long-term outcomes after liver transplantation

BACKGROUND

Tacrolimus trough levels (TTL) during the first weeks after liver transplantation (LT) have been related with long-term renal function and hepatocellular carcinoma recurrence. Nevertheless, the significance of trough levels of tacrolimus during the early post-transplant period for the long-term outcome is under debate

AIM

To evaluate the effect of TTL during the first month on the long-term outcomes after LT.

METHODS

One hundred fifty-five LT recipients treated de novo with once-daily tacrolimus were retrospectively studied. Patients with repeated LT or combined transplantation were excluded as well as those who presented renal dysfunction prior to transplantation and/or those who needed induction therapy. Patients were classified into 2 groups according to their mean TTL within the first month after transplantation: ≤ 10 (n = 98) and > 10 ng/mL (n = 57). Multivariate analyses were performed to assess risk factors for patient mortality.

RESULTS

Mean levels within the first month post-transplant were 7.4 ± 1.7 and 12.6 ± 2.2 ng/mL in the ≤ 10 and > 10 groups, respectively. Donor age was higher in the high TTL group 62.9 ± 16.8 years vs 45.7 ± 17.5 years (P = 0.002) whilst mycophenolate-mofetil was more frequently used in the low TTL group 32.7% vs 15.8% (P = 0.02). Recipient features were generally similar across groups. After a median follow-up of 52.8 mo (range 2.8-81.1), no significant differences were observed in: Mean estimated glomerular filtration rate (P = 0.69), hepatocellular carcinoma recurrence (P = 0.44), de novo tumors (P = 0.77), new-onset diabetes (P = 0.13), or biopsy-proven acute rejection rate (12.2% and 8.8%, respectively; P = 0.50). Eighteen patients died during the follow-up and were evenly distributed across groups (P = 0.83). Five-year patient survival was 90.5% and 84.9%, respectively (P = 0.44), while 5-year graft survival was 88.2% and 80.8%, respectively (P = 0.42). Early TTL was not an independent factor for patient mortality in multivariate analyses.

CONCLUSION

Differences in tacrolimus levels restricted to the first month after transplant did not result in significant differences in long-term outcomes of LT recipients.

Long-term Management of the Adult Liver Transplantation Recipients

The survival of liver transplantation (LT) recipients has been improved remarkably in short-term. The major causes of mortality in long-term include nonimmunological causes such as cardiovascular, de novo malignancy, chronic kidney disease, and recurrence of primary disease. Rejection-related mortality is rare in the long-term after LT. We discuss nonrejection causes of long-term morbidity/mortality, risk factors, and management strategies in LT recipients. In addition, we discuss osteoporosis, contraception, and pregnancy in LT recipients.

Delayed Calcineurin Inhibitor Introduction Without Antibody Induction in Liver Transplantation Is Safe and Helps Preserve Kidney Function

INTRODUCTION

Acute kidney injury (AKI) is common after liver transplantation and affects outcome after liver transplantation. Antibody induction is commonly used to reduce dose and/or to delay introduction of calcineurin inhibitor (CNI) but is very expensive. We propose a modified immunosuppressive protocol that delays administration of CNI for 48 to 72 hours without antibody induction. This study evaluates the results of our new protocol.

MATERIAL AND METHODS

A retrospective case-control study was performed. Study patients had induction with steroid and mycophenolate mofetil without antibody induction, and CNI administration was delayed for 48 to 72 hours. Control patients received CNI and steroid induction without antibody induction, and CNI was continued posttransplant. AKI was defined as an increase in serum creatinine level of at least 1.5 times the pretransplant baseline within the first postoperative week.

RESULTS

Sixty liver transplant recipients from 2013 to 2015 were included in this study (30 in the delayed CNI group and 30 in the control group). The patient characteristics and intraoperative factors were comparable in both groups. AKI developed in 11 patients in the study group and in 20 patients in the control group (37% vs 66.7%; P = .02). There was no acute rejection observed in the first month in either group.

CONCLUSION

We have demonstrated that delayed CNI introduction without antibody induction is safe and helps preserve kidney function. Antibody induction can be omitted safely in a delayed CNI introduction protocol to reduce the cost of liver transplantation without increasing the risk of acute rejection.

Exploring Reference Values for Hair Cortisol: Hair Weight Versus Hair Protein

BACKGROUND

As a marker of cumulative cortisol activity, hair cortisol has received attention in clinical and methodological research. Currently, it is a common practice to relate the hair cortisol concentration (HCC) to hair weight. This article explores the hair protein concentration (HPC) as another possible reference value for HCC.

METHODS

For n = 18 hair samples cut from the posterior vertex, the HCC, HPC, and hair sample weight were determined, and the cortisol-to-weight and cortisol-to-protein ratios were calculated. Correlations were analyzed between the HCC, HPC, and hair sample weight as well as between the cortisol-to-weight and cortisol-to-protein ratios. Hair sample weight and HPC were included as independent variables in a stepwise linear regression model to predict HCC.

RESULTS

The HCC and HPC did not correlate significantly (r = 0.393, P = 0.106); however, the correlation between HCC and hair sample weight was significant (r = 0.520, P = 0.027). The HPC and hair sample weight (r = 0.605, P = 0.008) as well as the cortisol-to-weight and cortisol-to-protein ratios (r = 0.858, P < 0.000) showed a high correlation. The hair sample weight was the better predictor of the HCC (β = 0.520, P = 0.027) than HPC (β = 0.125, P = 0.657).

CONCLUSIONS

The results indicate that the hair sample weight is the more suitable reference value for the HCC. Thus, the standard cortisol-to-weight ratio should be used as the preferred expression for the cumulative cortisol activity measured in the scalp hair. However, calculating the cortisol-to-protein ratio can be considered as an alternative if the hair sample weight is not available.

Incidence, Predictors, and Impact on Survival of Long-term Cardiovascular Events After Liver Transplantation

BACKGROUND

Information on the risk factors, particularly kidney function, and impact of long-term cardiovascular events (CVE) after liver transplantation (LT) remains scarce.

METHODS

This is a retrospective, single-center study that included consecutive LT recipients between 2007 and 2017. The incidence of CVE, their risk factors, and their impact on patient survival were investigated.

RESULTS

We included 627 LT recipients. The incidence of CVE was 8% and 20% at 12 and 60 months after LT, respectively. The independent risk factors of long-term (beyond 12 mo) CVE were age at LT (hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.01-1.07), male gender (HR, 2.48; 95% CI, 1.21-5.05), history of pre-LT cardiovascular disease (HR, 2.19; 95% CI, 1.2-3.98), and immunosuppression with cyclosporine A (HR, 1.93; 95% CI, 1.14-3.3). In patients with pre-LT cardiovascular disease, creatinine levels 12 months after LT significantly impacted the risk of long-term CVE. Long-term CVE (HR, 2.12; 95% CI, 1.24-3.61), hepatitis C as the etiology of liver disease (HR, 2.18; 95% CI, 1.29-3.67), cytomegalovirus infection (HR, 1.89; 95% CI, 1.08-3.3), and donor age (HR, 1.02; 95% CI, 1.01-1.04) were independent factors associated with post-LT patient death.

CONCLUSIONS

Age, male gender, cardiovascular disease before LT, and cyclosporine A were associated with the risk of long-term CVE. The impact of serum creatinine was restricted to patients with pre-LT cardiovascular disease. In these patients, preservation of kidney function early after LT may lessen the incidence of CVE, which are an independent predictor of post-LT death.

Impact of Induction Immunosuppression Strategies in Simultaneous Liver/Kidney Transplantation

BACKGROUND

There is scant data on the use of induction immunosuppression for simultaneous liver/kidney transplantation (SLKT).

METHODS

We analyzed the Organ Procurement and Transplant Network registry from 1996 to 2016 to compare outcomes of SLKT, based on induction immunosuppression.

RESULTS

Of 5172 patients, 941 (18%) received T-cell depletion induction, 1635 (32%) received interleukin 2 receptor antagonist (IL2-RA), and 2596 (50%) received no induction (NI). At 5 years, patient survivals were 68% in the T-cell group, 74% in the IL2-RA group, and 71% in the NI group (P = 0.0006). Five-year liver and kidney allograft survivals were 67% and 64% in the T-cell group, 73% and 70% in the IL2-RA group, and 70% and 68% in the NI group (P = 0.001 and 0.003), respectively. On multivariate analysis, the type of induction had no impact on patient or allograft survival. Maintenance steroids and calcineurin inhibitors (CNIs) at discharge were associated with improved patient and graft survival (steroids: patient survival hazard ratio [HR] 0.37 [0.27-0.52], liver survival HR 0.43 [0.31-0.59], kidney survival HR 0.46 [0.34-0.63]; P < 0.0001, CNI: patient survival HR 0.3 [0.21-0.43], liver survival HR 0.3 [0.2-0.44], kidney survival HR 0.4 [0.26-0.59]; P < 0.0001). CNI maintenance in patients who received T-cell induction was associated with decreased patient, liver, and kidney allograft survivals (respective HR: 1.4 [1.1, 1.8]; 1.5 [1.1, 1.9]; 1.3 [1.08, 1.7]; P < 0.05) CONCLUSION.: Induction immunosuppression had no impact on patient and allograft survival in SLKT, while maintenance steroids and CNI were associated with improved patient and graft survivals. Given the inherent limitations of a registry analysis, these findings should be interpreted with caution.

Renal disease in the allograft recipient

Chronic renal failure after liver transplantation (LT) is significantly more frequent than after lung or heart transplantation and it results in an increased short and long-term mortality. Renal impairment may occur before LT (functional or due to preexisting parenchymal kidney disease), in the peri-operative period or later after LT. The number of patients with renal failure after LT has increased due to the liver allocation based on MELD and to the more liberal use of higher risk grafts. Calcineurin inhibitor (CNI) nephrotoxicity is the most important cause of renal dysfunction but is a modifiable factor. Strategy to prevent CNI-associated nephrotoxicity is post-op CNI minimization by induction therapy and reduced dose and/or delayed introduction of CNI in combination with mycophenolate mofetil (MMF) or everolimus with no penalty in term of rejection. With everolimus, usually started one month after LT, a drastic minimization of CNI is possible and this results in superior kidney function until at least 3 years follow up. At the moment of renal impairment a drastic reduction of CNI dose together with the introduction of MMF results in an improvement in GFR at 6 to 2 years with a low rate of acute rejection. However, secondary prevention fails to normalize renal function in most of the patients once e GFR <60 ml/min/1.73m²ml.

Prognostic value of endogenous and exogenous metabolites in liver transplantation

Liver transplantation has been widely accepted as an effective intervention for end-stage liver diseases and early hepatocellular carcinomas. However, a variety of postoperative complications and adverse reactions have baffled medical staff and patients. Currently, transplantation monitoring relies primarily on nonspecific biochemical tests, whereas diagnosis of multiple complications depends on invasive pathological examination. Therefore, a noninvasive monitoring method with high selectivity and specificity is desperately needed. This review summarized the potential of endogenous small-molecule metabolites as biomarkers for assessing graft function, ischemia-reperfusion injury and liver rejection. Exogenous metabolites, mainly those immunosuppressive agents with high intra- and inter-individual variability, were also discussed for transplantation monitoring.

Immunosuppression in liver transplant

The increasing potency of immunosuppression (IS) agents resulted in significantly decreased rates of steroid resistant rejection and rejection related graft loss in liver transplantation (LT). Currently, more than two thirds of late mortality after LT is unrelated to graft function. However, the increased benefit of more potent IS drugs, coupled with the prolonged survival of transplant recipients led to longer patients exposure to these drugs and their unwanted adverse effects, creating a double-edged sword. In this article the authors describe the mechanism of action and the adverse effects of the most commonly used immunosuppressed drugs, and the most commonly used IS regimens for both induction and maintenance regimens. The balance between the ideal IS regimen to prevent rejection and the need to minimize the dose of IS drugs in order to prevent the adverse effects related to its use requires the knowledge of the science and the experience with the art of medicine. The different protocols aimed at protecting renal function and preventing the development of de novo cancer and metabolic syndrome are discussed here. The main causes of mortality late after liver transplant are associated with prolonged use of IS medications, and clear evidence exists about over-immunosuppression of recipients of liver transplant. The current status of strategies of IS minimization and withdrawal are reviewed in this article, with evaluation of its benefits and pitfalls.

Management of Hepatorenal Syndrome: A Review

Acute kidney injury (AKI) occurs frequently in patients with cirrhosis, and hepatorenal syndrome (HRS) is second most common etiology of AKI after volume responsible pre-renal etiology. AKI in these patients negatively impacts pre- and post-transplant patient survival and healthcare burden. Reduced effective blood volume with consequent reduced renal blood flow, along with systemic inflammation in patients with decompensated cirrhosis, result in susceptibility to HRS. In this article, we will review updates over the last 5 years on the changing definition with diagnostic criteria and nomenclature of AKI and HRS, data on medical treatment with vasoconstrictors, and urinary biomarkers in diagnosis of etiology of AKI. We will also discuss the significance of liver transplantation evaluation once the diagnosis of HRS is established and the post-transplant immunosuppression management. We will also review one of the challenging issues that remains among transplant-eligible patients, that of allocation of simultaneous liver kidney transplant. Finally, we will review the new implemented policy from the Organ Procurement Transplant Network on simultaneous liver kidney allocation.

Area Under Trough Concentrations of Tacrolimus as a Predictor of Progressive Renal Impairment After Liver Transplantation

BACKGROUND

Tacrolimus minimization is usually restricted to patients with pretransplant renal impairment, and this strategy could result into worse renal outcomes after liver transplantation (LT).

METHODS

A consecutive cohort of 455 LT patients receiving tacrolimus-based immunosuppression was studied (2008-2013). Cumulative exposure to tacrolimus was calculated as the area under curve of trough concentrations (AUCtc). Patients were stratified as tacrolimus minimization, conventional, or high exposure, according to the thresholds based in the COMMIT consensus. Estimated glomerular filtration rates (eGFR) were assessed by the Modification of Diet in Renal Disease formula (MDRD-4) up to 5 years after LT.

RESULTS

Seventy patients (15.4%) had pretransplant eGFR < 60 mL/min, which was associated with increased mortality rates, particularly within the first 5 years post-LT (31.4% versus 17.5%; Breslow P = 0.010). After LT, there was an abrupt eGFR decline within the first 3 months (median 18.6 mL/min; P < 0.001), further decreasing up to 12 months (additional 3 mL/min), without any improvement thereafter. According to AUCtc, 33.7% of patients received tacrolimus minimization, 44.8% conventional exposure, and 21.5% high exposure. Conventional/high exposure to tacrolimus resulted in a more pronounced eGFR decline within the first 3 months when compared with minimization (23.3 mL/min versus 9.5 mL/min; P < 0.001). This gap was even higher in patients with initially preserved renal function. Tacrolimus AUCtc was an independent predictor of eGFR decline within the first 3 months after controlling for potential confounders.

CONCLUSIONS

AUCtc is a surrogate of cumulative exposure to tacrolimus and may be helpful for routine dose adjustments. Tacrolimus minimization should be universally attempted after LT to preserve renal function.

Everolimus and long-term decline in renal function after liver transplantation: real-life experience with measured GFR

Switching from calcineurin-inhibitors (CNI) to everolimus >6-12-months after liver transplantation (LT) seems inefficient in improving renal function, but whether everolimus halts further renal-function decline compared to low-dose CNI remains unclear. In a retrospective single-center study of everolimus after LT (2008-2016) with routine measured glomerular filtration rates (mGFR; ⁵¹Cr-EDTA- or iohexol clearance), we compared by propensity-score matching everolimus therapy to low-dose CNI therapy. The study comprised 36 patients with everolimus introduced on average 22 months post-LT (range 2-105 months, median follow-up 3.4 years), and 36 matched controls. Everolimus introduction was associated with a mean improvement in mGFR of 7 mL/min up to 1 year (p = .003), restricted to patients switched <1-year post-transplant and at tacrolimus trough levels >5 ng/mL. The differences between the everolimus group and controls in delta-mGFR from baseline to 1 year (7.3 vs 4.3 mL/min, p = .25) or 1-year to last follow-up (-0.8 vs -0.2 mL/min/year, p = .71) were non-significant. Proportions with mGFR decline >3 mL/min/year were similar between groups (11% and 14%, p = 1.00). Everolimus was stopped in three patients (8%), and acute rejection occurred in 17%. In conclusion, despite an early improvement in renal function after everolimus introduction, we found no evidence that everolimus halts the long-term mGFR decline compared to continued low-dose CNI therapy. Due to retrospective design, small sample size and heterogenous characteristics, definite conclusions require prospective studies.