Immunosuppression induction with rabbit anti-thymocyte globulin with or without rituximab in 1000 liver transplant patients with long-term follow-up

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.

Pleural Effusion and Malnutrition Are Associated With Worse Early Outcomes After Liver Transplant

INTRODUCTION

Pulmonary complications after liver transplantation (LT) have previously been associated with longer hospital stays and ventilator time, and higher mortality. This study reports the outcomes for a specific pulmonary complication, pleural effusion, in LT recipients.

METHODS

Records from a single transplant center were analyzed retrospectively for all adult LT patients. Patients with documented pleural effusion by radiographic imaging within 30 days pre- or post-transplant were considered as cases. Outcomes included length of hospital stay, discharge disposition, hospital readmission, discharge with home oxygen, and 1-year survival.

RESULTS

During the 4-year study period, 512 LTs were performed, with 107 patients (21%) developing a peri-transplant pleural effusion. In total, 49 patients (10%) had a pre-transplant effusion, 91 (18%) had a post-transplant effusion, and 32 (6%) had both. Characteristics associated with the presence of any pleural effusion included an increasing model for end-stage liver disease score, re-transplantation, diagnosis of alcoholic liver disease, low protein levels, and sarcopenia. Effusion patients had longer hospital stays (17 vs 9 days, P < .001) and higher likelihood of discharge to a care facility (48% vs 21%, P < .001). Ninety-day readmission occurred in 69% of effusion patients (vs 44%, P < .001). One-year patient survival with any effusion was 86% (vs 94%, P < .01).

CONCLUSIONS

Overall, 21% of recipients developed a clinically significant peri-transplant pleural effusion. Pleural effusion was associated with worse outcomes for all clinical measures. Risk factors for the development of pleural effusion included higher MELD score (>20), re-transplantation, alcoholic liver disease, and poor nutrition status, including poor muscle mass.

Induction Immunosuppression Does Not Worsen Tumor Recurrence After Liver Transplantation for Hepatocellular Carcinoma

BACKGROUND

Prior studies are inconsistent regarding the impact of antibody induction therapy on outcomes after liver transplantation (LT) for hepatocellular carcinoma (HCC).

METHODS

Adults transplanted with HCC exception priority were identified from February 27, 2002, to March 31, 2019, using the United Network for Organ Sharing database. Time-to-event analyses evaluated the association of antibody induction therapy (none, nondepleting induction [NDI], depleting induction [DI]) with overall post-LT patient survival and HCC recurrence. Separate multivariable models adjusted for tumor characteristics on either last exception or on explant. The interaction of induction and maintenance regimen at LT discharge was investigated.

RESULTS

Among 22 535 LTs for HCC, 17 688 (78.48%) received no antibody induction, 2984 (13.24%) NDI, and 1863 (8.27%) DI. Minimal differences in patient and tumor characteristics were noted between induction groups, and there was significant center variability in practices. NDI was associated with improved survival, particularly when combined with a calcineurin inhibitor (CNI) and antimetabolite (hazard ratio [HR] 0.73 versus no induction plus 3-drug therapy in the last exception model [ P  < 0.001]; HR 0.64 in the explant model [ P  = 0.011]). The combination of DI with CNI alone was also protective (HR 0.43; P  = 0.003). Neither NDI nor DI was associated with tumor recurrence (all P  > 0.1). However, increased HCC recurrence was observed with no induction plus CNI monotherapy (HR 1.47, P  = 0.019; versus no induction plus 3-drug therapy).

CONCLUSIONS

In conclusion, induction immunosuppression was not associated with worse post-LT outcomes in patients transplanted with HCC exception priority. An improvement in survival was possibly observed with NDI.

[Update: Immunosuppression in organ transplantation]

Immunosuppression is an essential prerequisite for successful transplantation. In order to reduce the sometimes-considerable side effects, combination therapies with different agents are used. This article aims to provide an up-to-date overview of immunosuppression after liver and kidney transplantation.

Predictors of Kidney Delayed Graft Function and Its Prognostic Impact following Combined Liver-Kidney Transplantation: A Recent Single-Center Experience

Combined liver−kidney transplantation (CLKT) improves patient survival among liver transplant recipients with renal dysfunction. However, kidney delayed graft function (kDGF) still represents a common and challenging complication that can negatively impact clinical outcomes. This retrospective study analyzed the incidence, potential risk factors, and prognostic impact of kDGF development following CLKT in a recently transplanted cohort. Specifically, 115 consecutive CLKT recipients who were transplanted at our center between January 2015 and February 2021 were studied. All transplanted kidneys received hypothermic pulsatile machine perfusion (HPMP) prior to transplant. The primary outcome was kDGF development. Secondary outcomes included the combined incidence and severity of developing postoperative complications; development of postoperative infections; biopsy-proven acute rejection (BPAR); renal function at 1, 3, 6, and 12 months post-transplant; and death-censored graft and patient survival. kDGF was observed in 37.4% (43/115) of patients. Multivariable analysis of kDGF revealed the following independent predictors: preoperative dialysis (p = 0.0003), lower recipient BMI (p = 0.006), older donor age (p = 0.003), utilization of DCD donors (p = 0.007), and longer delay of kidney transplantation after liver transplantation (p = 0.0003). With a median follow-up of 36.7 months post-transplant, kDGF was associated with a significantly increased risk of developing more severe postoperative complication(s) (p < 0.000001), poorer renal function (particularly at 1 month post-transplant, p < 0.000001), and worse death-censored graft (p = 0.00004) and patient survival (p = 0.0002). kDGF may be responsible for remarkable negative effects on immediate and potentially longer-term clinical outcomes after CLKT. Understanding the important risk factors for kDGF development in CLKT may better guide recipient and donor selection(s) and improve clinical decisions in this increasing group of transplant recipients.

Immunosuppression, Compliance, and Tolerance After Orthotopic Liver Transplantation: State of the Art

Orthotopic liver transplantation is the treatment of choice for several otherwise irreversible forms of acute and chronic liver diseases. Early implemented immunosuppressant regimens have had disappointing results with high rejection rates. However, new drugs have reduced the daily immunosuppression requirements, thereby improving graft and patient survival as well as kidney function. Liver rejection is a T-cell-driven immune response and is the active target of immunosuppressive agents. Immunosuppressants can be divided into pharmacological or biological drugs: the gold standard is the calcineurin inhibitors, steroids, mycophenolate mofetil, and mechanistic target of rapamycin inhibitors. Compliance with these agents is essential, although they can increase the risk of infections and neoplastic diseases. In some patients, graft tolerance can be achieved. Graft tolerance is defined as the absence of acute and chronic rejection in a graft, with normal function and histology in an immunosuppression-free, fully immunocompetent host, usually as the final result of a successful attempt at immunosuppression withdrawal. The occurrence of immunosuppressive-related complications has led to new protocols aimed at protecting renal function and preventing de novo cancer and dysmetabolic syndrome. The backbone of immunosuppression remains calcineurin inhibitors in association with other drugs, mainly over the short-term period. To avoid rejection and the side effects on renal dysfunction, de novo cancer, and cardiovascular syndrome, optimal long-term immunosuppressive therapy should be tailored in liver transplant recipients.

HLA-DR Mismatch and Black Race Are Associated With Recurrent Autoimmune Hepatitis After Liver Transplantation

Supplemental Digital Content is available in the text.

The predictors of recurrent autoimmune hepatitis (R-AIH) after liver transplantation (LT) are heterogeneous with limited data to guide immunosuppression, with little data on impact of race.

Update: Immunsuppression bei Organtransplantationen

Die Immunsuppression ist eine wesentliche Grundvoraussetzung für eine erfolgreiche Transplantation. Zur Reduktion der teils beträchtlichen Nebenwirkungen werden Kombinationstherapien mit unterschiedlichen Wirkstoffen durchgeführt. Dieser Beitrag soll einen aktuellen Überblick zur Immunsuppression nach Leber- und Nierentransplantation geben.

Tracheostomy Post Liver Transplant: Predictors, Complications, and Outcomes

Background

Liver transplant (LT) patients have an increased risk of postoperative respiratory failure requiring tracheostomy. This study sought to characterize objective clinical predictors of tracheostomy.

Material/Methods

The records for 2017 LT patients at a single institution were reviewed. Patients requiring tracheostomy were first compared with all other patients. A case-control subgroup analysis was conducted in which 98 tracheostomy patients were matched with 98 non-tracheostomy LT patients. For the case-control study, muscle mass was assessed using preoperative computed tomography scans.

Results

Among 2017 LT patients, 98 required tracheostomy (5%), with a 19% complication rate. Tracheostomy patients were older and had a higher model for end-stage liver disease score, a lower body mass index (BMI), and a greater smoking history. Tracheostomy patients had a longer hospital stay (45 vs. 10 days, P<0.001) and worse 1-year survival (65% vs. 91%, P<0.001). Ten-year Cox regression patient survival for tracheostomy patients was significantly worse (32% vs. 68%, P<0.001). In the case-control analysis, respiratory failure patients were older (P<0.01) and had a lower BMI (P=0.05). They also had a muscle mass deficit of −39% compared with matched LT controls (P<0.001). No significant differences were seen with pre-LT total protein or albumin or with forced expiratory volume in 1 s divided by forced vital capacity (FEV1/FVC) values.

Conclusions

Predictors for respiratory failure requiring post-LT tracheostomy include higher model for end-stage liver disease score, older age, lower BMI, greater smoking history, and worse sarcopenia. Patients requiring tracheostomy have dramatically longer hospital stays and worse survival.

Postoperative Atrial Fibrillation and Flutter in Liver Transplantation: An Important Predictor of Early and Late Morbidity and Mortality

Postoperative atrial fibrillation/flutter (POAF) is the most common perioperative arrhythmia and may be particularly problematic after liver transplantation (LT). This study is a single-center retrospective analysis of POAF to determine its incidence following LT, to identify risk factors, to assess its impact on clinical outcomes, and to summarize management strategies. The records of all patients who underwent LT between 2010 and 2018 were reviewed. Extracted data included pre-LT demographics and cardiac evaluation, in-hospital post-LT cardiac events, early and late complications, and survival. Among 1011 patients, the incidence of post-LT POAF was 10%. Using binary logistic regression, pre-LT history of atrial fibrillation was the strongest predictor of POAF (odds ratio [OR], 6.72; 95% confidence interval [CI], 2.00-22.57; P < 0.001), followed by history of coronary artery disease (CAD; OR, 2.52; 95% CI, 1.10-5.81; P = 0.03). Cardiac stress testing abnormality and CAD on cardiac catheterization were also associated with higher risk. Median time to POAF onset after LT was 3 days with 72% of cases resolving within 48 hours. POAF patients had greater hospital length of stay, death during the LT admission, and 90-day and 1-year mortality. POAF was an independent risk factor for post-LT mortality (OR, 2.0; 95% CI, 1.3-3.0; P < 0.01). Amiodarone was administered to 73% of POAF patients with no evidence of increased serum alanine aminotransferase levels. POAF occurred in 10% of post-LT patients with early onset and rapid resolution in most affected patients. POAF patients, however, had significant morbidity and mortality, suggesting that POAF is an important marker for worse early and late post-LT outcomes.

Rapid Decrease in Liver Graft Steatosis in the Early Post-transplant Period: A Blinded and Randomized Study

AIMS

Previous research suggests a rapid post-transplant decrease in liver steatosis. With increased use of liver grafts with steatosis, better understanding of this post-transplant change will facilitate successful liver transplantation. This study compares liver reperfusion biopsies with early post-transplant surveillance biopsies to evaluate and quantitate change in steatosis.

METHODS

All liver grafts with ≥ 10% steatosis were extracted for analysis. Allograft biopsies on day 0 and day 3 post-transplant were randomly read, in a blinded fashion, by a single, experienced liver pathologist. Ten non-steatotic grafts were interspersed as controls. Slides were scored for macro-, micro-, and total steatosis.

RESULTS

Overall, 151 subjects with steatosis were available for study. A decrease in steatosis was seen for most grafts: microvesicular (69%), macrovesicular (64%), and total steatosis (77%). There was a greater decrease in steatosis for grafts with high baseline steatosis (> 40% baseline steatosis with -30% reduction; 20%-39% baseline steatosis with -15% reduction; and < 20% baseline steatosis with -5% reduction).

CONCLUSIONS

These results confirm a marked post-transplant decrease in steatosis that occurs within 3 to 5 days for most liver grafts with steatosis. These findings support the continued use of liver grafts with steatosis as this pathology appears to resolve quickly after transplant.

Prognostic Impact of Peritransplant Serum Sodium Concentrations in Liver Transplantation

Background

Serum sodium (Na) is considered to reflect the severity of liver cirrhosis. In the last few years, much effort has been made to integrate this association into prognostic models after liver transplantation. The aim of this study was to investigate the associations between peritransplant Na and neurological complications, as well as short-term survival, after liver transplantation.

Material/Methods

A total of 306 liver transplantations between 2012 and 2015 were evaluated. Pre- and posttransplant sodium concentrations were investigated with regard to 3-month survival and incidence of posttransplant neurological complications, along with other factors present in the operative side of the recipient and donor.

Results

The 3-month survival rate was 94%. Neither hyponatremia (<130 mEq/L) nor hypernatremia (>145 mEq/L) at pretransplantion predicted 3-month survival. A large amount of intraoperative blood transfusion and a large delta Na showed a significant association with poor outcomes at 3 months. On multivariate analysis, the requirement of blood transfusion and warm ischemia time remained independent prognostic factors for 3-month mortality. Hyponatremia and a large delta Na tended to lead to the frequent development of neurological complications. These complications, secondary to rapid Na correction, were concerning and potentially led to a prolonged hospital stay and early mortality.

Conclusions

Rapid change in the sodium level might be caused by large amounts of blood transfusion products. This leads to a diminished short-term survival, as well as a higher rate of neurological complications.

Metabolomic Characterization of Human Model of Liver Rejection Identifies Aberrancies Linked to Cyclooxygenase (COX) and Nitric Oxide Synthase (NOS)

BACKGROUND Acute liver rejection (ALR), a significant complication of liver transplantation, burdens patients, healthcare payers, and the healthcare providers due to an increase in morbidity, cost, and resources. Despite clinical resolution, ALR is associated with an increased risk of graft loss. A unique protocol of delayed immunosuppression used in our institute provided a model to characterize metabolomic profiles in human ALR. MATERIAL AND METHODS Twenty liver allograft biopsies obtained 48 hours after liver transplantation in the absence of immunosuppression were studied. Hepatic metabolites were quantitated in these biopsies by liquid chromatography and mass spectroscopy (LC/MS). Metabolite profiles were compared among: 1) biopsies with reperfusion injury but no histological evidence of rejection (n=7), 2) biopsies with histological evidence of moderate or severe rejection (n=5), and 3) biopsies with histological evidence of mild rejection (n=8). RESULTS There were 133 metabolites consistently detected by LC/MS and these were prioritized using variable importance to projection (VIP) analysis, comparing moderate or severe rejection vs. no rejection or mild rejection using partial least squares discriminant statistical analysis (PLS-DA). Twenty metabolites were identified as progressively different. Further PLS-DA using these metabolites identified 3 metabolites (linoleic acid, γ-linolenic acid, and citrulline) which are associated with either cyclooxygenase or nitric oxide synthase functionality. CONCLUSIONS Hepatic metabolic aberrancies associated with cyclooxygenase and nitric oxide synthase function occur contemporaneous with ALR. Additional studies are required to better characterize the role of these metabolic pathways to enhance utility of the metabolomics approach in diagnosis and outcomes of ALR.

De Novo Head and Neck Cancer After Liver Transplant With Antibody-Based Immunosuppression Induction

BACKGROUND

Powerful antibody-based immunosuppression induction is now used routinely during organ transplantation and may place patients at even higher risk of post-transplant cancer.

MATERIALS AND METHODS

Incidence of de novo head and neck cancer was extracted from the records of 1685 consecutive adult deceased donor liver transplant recipients with a minimum 1-year follow-up from 2001 to 2015. There were 121 patients positively identified as having developed de novo head and neck cancer post-liver transplant. Records of these patients were analyzed to determine demographics, history of cancer pre-liver transplant, de novo cancer type and location, treatment modalities, and alcohol and tobacco exposure.

RESULTS

Of the 121 patients who developed cancer of the head and neck (7%), there were 103 cutaneous (6%) and 25 noncutaneous (1%). For noncutaneous cancers, factors associated with increased risk of cancer included alcohol abuse (P < .001), any smoking history (P = .05), and increasing exposure to tobacco (P < .01). Ten-year Cox regression patient survival demonstrates a survival disadvantage for patients who develop noncutaneous cancer (P  = .06) but a survival advantage for patients who develop cutaneous cancer (P < .01).

CONCLUSIONS

The incidence and pattern of head and neck cancer in this population of liver transplant recipients was similar to those published previously, suggesting that induction immunosuppression does not increase risk of these types of cancers. Long-term survival was worse for patients with noncutaneous cancers, but better for those with cutaneous cancers, though the reason is unclear.

Steroid-free three-drug maintenance regimen for pancreas transplant alone: Comparison of induction with rabbit antithymocyte globulin +/- rituximab

Graft survival following pancreas transplant alone (PTA) is inferior to other pancreas transplants. Steroid elimination is appealing, but a two-drug maintenance strategy may be inadequate. Additionally, recipients tend to have diabetic nephropathy and do not tolerate nephrotoxic medications. A three-drug maintenance strategy permits immunosuppression through different mechanisms as well as an opportunity to use lower doses of the individual medications. Induction consisted of five doses of rabbit antithymocyte globulin (1 mg/kg/dose). As of October 2007, a single dose of rituximab (150 mg/m² ) was added. Maintenance consisted of tacrolimus, sirolimus and mycophenolate mofetil. From 2004 to 2017, 166 PTA were performed. Graft loss at 7 and 90 days were 4% and 5%, and 1-year patient and graft survival were 97% and 91%. Comparing induction without and with rituximab, there was no significant difference in 7- or 90-day graft loss, 1-year patient or graft survival, or in the rate of rejection or infection. Rabbit antithymocyte globulin induction and steroid withdrawal followed by a three-drug immunosuppression regimen is an excellent strategy for PTA recipients.

Impact of Donor Pre-Procurement Cardiac Arrest (PPCA) on Clinical Outcomes in Liver Transplantation

Background

Transplantation of liver grafts from deceased donors who experienced cardiac arrest prior to liver procurement is now common. This single-center study analyzed the impact of pre-donation arrest time on clinical outcomes in liver transplantation.

Material/Methods

Records of all orthotopic liver transplants performed at a single center over a 15-year period were reviewed. Donor records were reviewed and total arrest time was calculated as cumulative minutes. Post-transplant liver graft function was assessed using laboratory values. Graft survival was assessed with Cox regression analysis.

Results

Records for 1830 deceased donor transplants were reviewed, and 521 donors experienced pre-procurement cardiac arrest (28%). Median arrest time was 21 min (mean 25 min, range 1–120 min). After transplant, the peak alanine aminotransferase and bilirubin levels for liver grafts from donors with arrest were lower compared to those for donors without arrest (p<0.001). Early allograft dysfunction occurred in 25% (arrest) and 28% (no arrest) of patients (p=0.22). There were no differences in risk of early graft loss (3% vs. 3%, p=0.84), length of hospital stay (10 vs. 10 days, p=0.76), and 1-year graft survival (89% vs. 89%, p=0.94). Cox regression analysis comparing 4 groups (no arrest, <20 min, 20–40 min, and >40 min arrest) demonstrated no statistically significant difference in survival at 10 years. Subgroup analysis of 93 donation after cardiac death grafts showed no significant difference for these same outcomes.

Conclusions

These results support the use of select deceased liver donors who experience pre-donation cardiac arrest. Pre-donation arrest may be associated with less early allograft dysfunction, but had no impact on long-term clinical outcomes. The results for donation after cardiac death donors were similar.

Low Total Dose of Anti-Human T-Lymphocyte Globulin (ATG) Guarantees a Good Glomerular Filtration Rate after Liver Transplant in Recipients with Pretransplant Renal Dysfunction

We aimed to evaluate the safety and efficacy of low doses of anti-T-lymphocyte globulin (ATG)-based immunosuppression in preserving renal function and preventing liver rejection in liver transplant (LT) recipients with pretransplant renal dysfunction. We designed a prospective single-center cohort study analyzing patients with pre-LT renal dysfunction defined as eGFR<60 mL/min/1.73m2, who underwent induction therapy with ATG (ATG group, n=20). This group was compared with a similar retrospective cohort treated with basiliximab (BAS group, n=20). An economic analysis between both induction therapies was also undertaken. In the ATG group, 45% and 50% of patients had recovered their renal function without acute cellular rejection (ACR) episodes at day 7 and 1 month after LT, respectively, versus 40% and 55% of patients in the BAS group (p=1). Renal function improved in both groups over time and no differences between groups were observed regarding one-year eGRF and one-year probability of ACR. Cost per patient of the ATG course was 403€ (r: 126-756) versus 2,524€ of the basiliximab course (p=0.001). In conclusion, induction with low dose of ATG or basiliximab in patients with pretransplant renal dysfunction is a good strategy for preserving posttransplant renal function; however the use of low-dose ATG resulted in a substantial reduction in drug costs. This trail is registered with ClinicalTrials.gov number: NCT01453218.

Class II Human Leukocyte Antigen Epitope Mismatch Predicts De Novo Donor-Specific Antibody Formation After Liver Transplantation

Formation of de novo donor-specific antibodies (dn-DSAs) has been associated with longterm immunologic complications after liver transplantation (LT). We hypothesized that human leukocyte antigen (HLA) epitope/eplet mismatch (MM) is a marker of immunogenicity and a risk factor for dn-DSA formation. Sera from 80 LT recipients were prospectively screened for dn-DSA by a Luminex single-antigen test (One Lambda, Inc., Canoga Park, CA) at 1, 2, 3, 6, 12, 18, 24, and 36 months after LT. HLA typing of the recipients and donors was performed using polymerase chain reaction (PCR)-SSP and PCR-SSOP Luminex low-resolution methods (One Lambda, Inc.). The HLAMatchmaker computer algorithm was used for identification of MM eplets at HLA-DRB1 and -DQA1/B1 loci. Luminex single-antigen bead solid phase assay was used for antibody analysis. Standard immunosuppression included thymoglobulin-rituximab induction and tacrolimus maintenance. There were 27 (34%) patients who developed dn-DSA. There were no episodes of antibody-mediated rejection, and 9 (11%) developed acute cellular rejection (ACR). A positive crossmatch status and a higher number of HLA-A, -B, -DR, and -ABDR MMs were not associated with dn-DSA formation. Patients developing dn-DSA had a significantly higher number of total (38 ± 2.7 versus 28 ± 2.3; P = 0.01) and antibody-verified (AbVer; 14 ± 1.1 versus 10 ± 1; P = 0.015) class II MM eplets. By a multivariate regression analysis, the number of class II MM eplets was strongly associated with risk of class II dn-DSA formation (odds ratio [OR], 1.2; P < 0.01). Patients with ACR had a significantly higher number of total (20.2 ± 1.3 versus 13.9 ± 0.9; P < 0.01) as well as AbVer (10.7 ± 1.1 versus 7.5 ± 0.6; P = 0.03) class I MM eplets. In conclusion, donor-recipient HLA epitope MM is associated with a risk of dn-DSA formation and rejection after LT. However, further studies are required to evaluate the clinical utility of epitope matching in LT.

Excellent outcomes in combined liver-kidney transplantation: Impact of kidney donor profile index and delayed kidney transplantation

The positive impact of delayed kidney transplantation (KT) on patient survival for combined liver-kidney transplantation (CLKT) has already been demonstrated by our group. The purpose of this study is to identify whether the quality of the kidneys (based on kidney donor profile index [KDPI]) or the delayed approach KT contributes to improved patient survival. In total, 130 CLKTs were performed between 2002 and 2015, 69 with simultaneous KT (group S) and 61 with delayed KT (group D) (performed as a second operation with a mean cold ischemia time [CIT] of 50 ± 15 hours). All patients were categorized according to the KDPI score: 1%-33%, 34%-66%, and 67%-99%. Recipient and donor characteristics were comparable within groups S and D. Transplant outcomes were comparable within groups S and D, including liver and kidney CIT, warm ischemia time, and delayed graft function. Lower KDPI kidneys (<34%) were associated with increased patient survival in both groups. The combination of delayed KT and KDPI 1%-33% resulted in 100% patient survival at 3 years. These results support that delayed KT in CLKT improves patient survival. The combination of delayed KT and low KDPI offers excellent patient survival up to 3 years. Improved outcomes in the delayed KT group including high KDPI kidneys supports expansion of the donor pool with the use of more extended criteria donor and donation after circulatory death kidneys. Liver Transplantation 24 222-232 2018 AASLD.

Management of Immunosuppression in Liver Transplantation

Liver transplantation outcomes have significantly improved over the past few decades owing largely to the introduction of effective immunosuppression medications. Further comprehension of the unique immune microenvironment of the liver has led to the development of newer molecular targeted therapeutics. Understanding the mechanism of action and adverse effect profiles of these medications is crucial for appropriate management of posttransplant patients. In this review, the author describes the immunologic response elicited by liver transplantation, chronicles the various immunosuppressant drug classes, discusses the evidence behind their use, and evaluates the management of special subpopulations of posttransplantation patients.

Superior Patient and Graft Survival in Adult Liver Transplant with Rabbit Antithymocyte Globulin Induction: Experience with 595 Patients

OBJECTIVES

The use of induction therapy in liver transplant is debatable. We aimed to compare clinical outcomes of different induction protocols in liver transplant recipients.

MATERIALS AND METHODS

This was a retrospective cohort analyses using the University of Washington Transplant Database from January 2005 to May 2012 for adult (≥ 18 y old) primary liver transplant patients. All patients received induction therapy. Maintenance immunosuppressive agents were tacrolimus or tacrolimus-mycophenolate mofetil. Primary endpoints were acute cellular rejection, patient survival, and graft survival. In patients with chronic hepatitis C, the degree of histologic inflammation or fibrosis at 1 year was assessed. Cox proportional hazards models were constructed to evaluate variables associated with both patient and graft survival.

RESULTS

We identified 595 patients: 322 patients received rabbit antithymocyte globulin and 273 received interleukin 2 receptor blocker. Acute cellular rejection was higher in patients who received interleukin 2 receptor blocker than in patients who received rabbit antithymocyte globulin (27% vs 18%; P < .03). Both patient survival at 1 year (95% vs 90%), 3 years (92% vs 87%), and 5 years (86% vs 80%) and graft survival at 1 year (93% vs 88%), 3 years (90% vs 86%), and 5 years (83% vs 78%) were superior with rabbit antithymocyte globulin than with the interleukin 2 receptor blocker (P < .002). In patients with hepatitis C virus, type of induction therapy did not have any effect on the timing of hepatitis C virus recurrence. At 1 year after transplant, 33.3% in the rabbit antithymocyte globulin group had grade 3/4 inflammation and 10.2% had stage 3/4 fibrosis, compared with 16.8% and 4.8% in the interleukin 2 receptor blocker group (P ≤ .002 and not significant). Female recipient, Model for End-Stage Liver Disease score, hepatocellular carcinoma, and high preoperative serum creatinine levels were associated with less favorable patient and graft survival.

CONCLUSIONS

Rabbit antithymocyte globulin is associated with lower rejection rate and improved patient and graft survival in liver transplant. Type of therapy affects the degree of histologic hepatitis C virus recurrence.

The Influence of Immunosuppressive Agents on the Risk of De Novo Donor-Specific HLA Antibody Production in Solid Organ Transplant Recipients

Production of de novo donor-specific antibodies (dnDSA) is a major risk factor for acute and chronic antibody-mediated rejection and graft loss after all solid organ transplantation. In this article, we review the data available on the risk of individual immunosuppressive agents and their ability to prevent dnDSA production. Induction therapy with rabbit antithymocyte globulin may achieve a short-term decrease in dnDSA production in moderately sensitized patients. Rituximab induction may be beneficial in sensitized patients, and in abrogating rebound antibody response in patients undergoing desensitization or treatment for antibody-mediated rejection. Use of bortezomib for induction therapy in at-risk patients is of interest, but the benefits are unproven. In maintenance regimens, nonadherent and previously sensitized patients are not suitable for aggressive weaning protocols, particularly early calcineurin inhibitor withdrawal without lymphocyte-depleting induction. Early conversion to mammalian target of rapamycin inhibitor monotherapy has been reported to increase the risk of dnDSA formation, but a combination of mammalian target of rapamycin inhibitor and reduced-exposure calcineurin inhibitor does not appear to alter the risk. Early steroid therapy withdrawal in standard-risk patients after induction has no known dnDSA penalty. The available data do not demonstrate a consistent effect of mycophenolic acid on dnDSA production. Risk minimization for dnDSA requires monitoring of adherence, appropriate risk stratification, risk-based immunosuppression intensity, and prospective DSA surveillance.

Worse Long-term Patient Survival and Higher Cancer Rates in Liver Transplant Recipients With a History of Smoking

BACKGROUND

This study is a retrospective review of liver transplant (LT) recipients to determine the impact of tobacco exposure on 10-year survival and de novo cancer (CA) incidence.

METHODS

The records of 1275 consecutive LT patients were reviewed (2001 to 2011). Patients were categorized as current, previous, or never smokers (NS) at listing for LT. Additionally, smokers were stratified by pack-years of tobacco exposure. Events included patient death, cardiovascular events, and de novo cancers. Cox regression analysis was used to evaluate survival. A complete cause of death analysis is provided, as well as a detailed tumor registry.

RESULTS

Current (n = 279) and previous smokers (n = 323) were more likely to have hepatocellular carcinoma (HCC) at transplant (25%, 29% vs 18% [NS], P < 0.001), and these 2 groups had higher HCC recurrence rates (21%, 14% vs 11% [NS], P = 0.18). De novo non-HCC CA was higher for current and previous smokers, compared to NS (18%, 16% vs 12% [NS], P = 0.05). Among those with de novo CA (n = 180), the 2 smoking groups were more likely to have non-skin CA (60%, 54% vs 27% [NS], P < 0.001). Patient survival at 10 years was worse for current smokers than the other study groups (55% vs 70%, P < 0.01). These results were largely mirrored with increased tobacco exposure.

CONCLUSIONS

The LT outcomes are uniformly worse for patients with a history of smoking, and the risk of negative events increases with increasing tobacco use. Smokers have higher rates of HCC and recurrence, de novo cancer, and worse long-term survival.

SUMMARY STATEMENT

This study summarizes the clinical outcomes for 1275 LT patients over 10 years, analyzing the impact of pre transplant recipient tobacco use. There are 47% of patients with a history of smoking. Because of demonstrated higher cancer rates and decreased survival, patients with a significant smoking history should be carefully scrutinized for liver transplantation.

Prognosis after recurrence of hepatocellular carcinoma in liver transplantation: predictors for successful treatment and survival

There are no established prognostic factors or standardized therapies for hepatocellular carcinoma (HCC) recurrence in liver transplantation (LT). The aim of this study was to investigate impact of underlying patient condition on treatment and outcomes of recurrence of HCC after LT. The medical records of 268 LT patients with HCC were evaluated. Potential prognostic factors for survival after recurrence were evaluated, including recurrent tumor characteristics, medical/radiological/surgical therapies for recurrence, and an inflammatory marker (neutrophil/lymphocyte ratio). Laboratory tests at recurrence, including albumin, absolute lymphocyte count (ALC), prognostic nutritional index (PNI: ALC(/μL) × 0.005 + Albumin(g/dL) × 10), were evaluated as surrogate markers for underlying patient conditions. A total of 51 (19%) patients developed HCC recurrence. The use of sirolimus and sorafenib significantly improved outcome (p = 0.007 and 0.04), and better nutritional status (PNI ≥ 40) enhanced their efficacy. On multivariate analysis, low ALC (<500/μL) and albumin (<2.8 g/L) remained independent prognostic factors (p = 0.03 and 0.02; hazard ratio = 3.61 [Ref. >1000/μL] and 4.97 [Ref. >3.5 g/dL], respectively). Low PNI (<40) showed significantly lower survival rate after adjusting the risk (p = 0.006, hazard ratio = 3.29). Underlying patient conditions and nutritional status, represented by ALC and albumin, are important to successful cancer treatment and strong prognostic markers for survival after HCC recurrence.

Review on immunosuppression in liver transplantation

The optimal level of immunosuppression in solid organ transplantation, in particular for the liver, is a delicate balance between the benefit of preventing rejection and the adverse side effects of immunosuppression. There is uncertainty about when this level is achieved in any individual recipient. Immunosuppression regimens vary between individual centers and changes with time as new agents and data are available. Presently concerns about the adverse side effects of calcineurin inhibitor, the main class of immunosuppressive agents used in liver transplantation (LT), has led to consideration of the use of antibody induction therapies for patients at higher risk of developing adverse side effects. The longevity of the transplanted organ is potentially improved by better management of rejection episodes and special consideration for tailoring of immunosuppression to the individual with viral hepatitis C, hepatocellular carcinoma or pregnancy. This review provides an overview of the current strategies for post LT immunosuppression and discusses modifications to consider for special patient populations.

New directions for rabbit antithymocyte globulin (Thymoglobulin(®)) in solid organ transplants, stem cell transplants and autoimmunity

In the 30 years since the rabbit antithymocyte globulin (rATG) Thymoglobulin^® was first licensed, its use in solid organ transplantation and hematology has expanded progressively. Although the evidence base is incomplete, specific roles for rATG in organ transplant recipients using contemporary dosing strategies are now relatively well-identified. The addition of rATG induction to a standard triple or dual regimen reduces acute cellular rejection, and possibly humoral rejection. It is an appropriate first choice in patients with moderate or high immunological risk, and may be used in low-risk patients receiving a calcineurin inhibitor (CNI)-sparing regimen from time of transplant, or if early steroid withdrawal is planned. Kidney transplant patients at risk of delayed graft function may also benefit from the use of rATG to facilitate delayed CNI introduction. In hematopoietic stem cell transplantation, rATG has become an important component of conventional myeloablative conditioning regimens, following demonstration of reduced acute and chronic graft-versus-host disease. More recently, a role for rATG has also been established in reduced-intensity conditioning regimens. In autoimmunity, rATG contributes to the treatment of severe aplastic anemia, and has been incorporated in autograft projects for the management of conditions such as multiple sclerosis, Crohn’s disease, and systemic sclerosis. Finally, research is underway for the induction of tolerance exploiting the ability of rATG to induce immunosuppresive cells such as regulatory T-cells. Despite its long history, rATG remains a key component of the immunosuppressive armamentarium, and its complex immunological properties indicate that its use will expand to a wider range of disease conditions in the future.

Is minimal, [almost] steroid-free immunosuppression a safe approach in adult liver transplantation? Long-term outcome of a prospective, double blind, placebo-controlled, randomized, investigator-driven study

OBJECTIVE

To investigate the safety of minimal immunosuppression (IS) in liver transplantation (LT).

BACKGROUND

The lack of long-term follow-up studies, including pathologic data, has led to a protean handling of IS in LT.

METHODS

Between February 2000 and September 2004, 156 adults were enrolled in a prospective, randomized, double-blind, placebo-controlled minimization trial comparing tacrolimus placebo (TAC-PLAC) and TAC short-term steroid (TAC-STER) IS. All patients had a minimum clinical, biochemical, and histological follow-up of 5 years.

RESULTS

Five-year actual patient and graft survival rates in TAC-PLAC and TAC-STER groups were 78.1% and 82.1% (P=0.89) and 74.2% and 76.9% (P=0.90), respectively. Five-year biopsies were available in 112 (89.6%) of 125 survivors. Twelve patients refused a biopsy because of their excellent evolution; tissue material was insufficient in 1 patient; 11 had normal liver tests; and 2 patients had developed alcoholic and secondary biliary cirrhosis. Histology was normal in 44 (39.3%) patients; 35 (31.3%) had disease recurrence. The remaining biopsies showed nonspecific chronic hepatitis (14.3%), mild inflammatory infiltrates (10.7%), and steatosis (3.5%). All findings were equally distributed between both groups. In each group, 3 patients (4.8%) presented with acute cellular rejection after the first year and only 1 (0.9%) TAC-PLAC patient developed chronic rejection after IS withdrawal because of pneumonitis. Arterial hypertension, diabetes mellitus, renal insufficiency, hypercholesterolemia, gout, and obesity were equally low in both groups.

CONCLUSIONS

Excellent long-term results can be obtained under minimal IS and absence of steroids. TAC-based monotherapy is feasible in most adult liver recipients until 5 years of follow-up.

Aminocaproic Acid (amicar) as an alternative to aprotinin (trasylol) in liver transplantation

INTRODUCTION

This study compared clinical outcomes for a large number of liver transplant patients receiving intraoperative epsilon-aminocaproic acid (EACA), aprotinin, or no antifibrinolytic agent over an 8-year period.

PATIENTS AND METHODS

Records for deceased donor liver transplants were reviewed. Data included antifibrinolytic agent, blood loss, early graft function, and postoperative complications. Study groups included low-dose aprotinin, high-dose aprotinin, EACA (25 mg/kg, 1-hour infusion), or no antifibrinolytic agent.

RESULTS

Data were included for 1170 consecutive transplants. Groups included low-dose aprotinin (n = 324 [28%]), high-dose aprotinin (n = 308 [26%]), EACA (n = 216 [18%]), or no antifibrinolytic (n = 322 [28%]). EACA had the lowest intraoperative blood loss and required the fewest transfusions of plasma. Patients receiving no agent required the most blood transfusions. Early graft loss was lowest in the EACA group, and 90-day and 1-year patient survival rates were significantly higher for the low-dose aprotinin and EACA groups according to Cox regression. Complications were similar, but there were more episodes of deep vein thrombosis in patients receiving EACA.

CONCLUSIONS

These results suggest that transitioning from aprotinin to EACA did not result in worse outcomes. In addition to decreased intraoperative blood loss, a trend toward improved graft and patient survival was seen in patients receiving EACA.

A new formula as a predictive score of post-liver transplantation outcome: postoperative MELD-lactate

INTRODUCTION

Liver transplantation (OLT) involves a 5% to 10% 30-day mortality rate. Multiple scores have been used as predictors of early postoperative mortality, such as the original Model for End-stage Liver Disease (MELD) and MELD sodium. Investigations have been conducted over the last 5 years to find new predictors of early post-OLT mortality.

OBJECTIVE

The aim of this study was to develop a new mathematical model to predict the individual chance of 30-day mortality after OLT.

METHODS

The study was conducted on 58 patients submitted to OLT at the University Hospital, between October 2008 and March 2012. The 29 latest survivor and 29 latest nonsurvivor cases were selected. Arterial blood sodium, lactate, international normalized ratio, total bilirubin, and creatinine values were determined 1 hour after the end of surgery. The MELD original equation, MELD sodium, and new MELD lactate were also elaborated. The results were analyzed by the Mann-Whitney and Wilcoxon tests. The level of significance was set at .05.

RESULTS

The new formula elaborated was as follows: MELD lactate = 5.68 × loge (lactate) + 0.64 × (Original MELD) + 2.68. The MELD lactate values were significantly higher than the MELD sodium and original MELD values (P < .05). The area under the receiver operating characteristic curve of MELD lactate in predicting the outcome of patients submitted to OLT was 0.80, as opposed to 0.71 for the original MELD and 0.72 for MELD sodium (P < .05).

CONCLUSION

The postoperative MELD lactate score proved to be more specific and sensitive than the original MELD and MELD sodium as a predictive model of the outcome of patients submitted to OLT.

Elevated alanine aminotransferase (ALT) in the deceased donor: impact on early post-transplant liver allograft function

BACKGROUND & AIMS

Serum alanine aminotransferase (ALT) levels are frequently elevated with liver injury and such elevations are common in deceased organ donors. The impact of this injury on early liver allograft function has not been well described. This study analyses the immediate function and 1-year graft and patient survival for liver allografts stratified by peak serum ALT levels in the deceased donor.

METHODS

The on-site organ procurement records for 1348 consecutive deceased liver donors were reviewed (2001–2011). Serum ALT was categorized into three study groups: normal/mild elevation, 0–499 μ/L; moderate elevation, 500–999 μ/L (>10× upper limit of normal) and severe elevation, ≥1000 μ/L (>20× upper limit of normal). Outcomes included early graft function and graft loss, and 1-year graft and patient survival.

RESULTS

Distribution of subjects included: normal/mild, 1259 (93%); moderate, 34 (3%) and severe, 55 (4%). Risk of 30-day graft loss for the three study groups was: 72 (6%), 3 (9%) and 3 (6%) (P = 0.74). Graft and patient survival at 1 year for the three groups was: normal/mild, 1031 (87%), 1048 (88%); moderate, 31 (91%), 31 (91%) and severe, 43 (88%), 44 (90%) (P = 0.71, 0.79). Cox proportional hazards modelling of survival while controlling for donor age and recipient model for end-stage liver disease score (MELD) demonstrates no statistically significant difference among the three study groups.

CONCLUSIONS

This study demonstrates clinical equivalence in early graft function and 1-year graft and patient survival for donor livers with varying peak levels of serum ALT. These donor allografts may, therefore, be utilized successfully.

Local allograft irradiation as an adjunct for treating severe resistant rejection after liver transplantation in adults

Acute rejection after liver transplantation occurs in one-third of all recipients and can be managed with conventional rejection therapy in the majority of cases. In rare instances, patients with severe acute rejection may be refractory to or have contraindications for conventional therapies. This case series evaluates the role of local allograft irradiation (LAI) as an adjunct for patients with rejection that is refractory to or contraindicated for conventional therapies. Additionally, the literature on the use of radiation therapy for reversing rejection in solid organ transplantation is reviewed. Five patients underwent 9 LAI treatments: 2 had refractory rejection, and 1 each had a malignancy, a concurrent life-threatening infection, and serum sickness with antibody therapy. Conventional rejection therapies included steroids, calcineurin inhibitors, and antithymocyte globulin. LAI consisted of 3 cycles of 1.5 Gy directed toward the liver allograft. Two of the 5 patients remained alive with excellent graft function. Six of the 9 treatments were successful in rescuing the liver allograft (reversing the rejection episode). Treatment success was associated with lower pretreatment serum bilirubin levels and higher pretreatment alanine aminotransferase levels. Compared with patients with immunosuppression-responsive severe acute rejection, those requiring LAI trended toward a later onset of first rejection. In conclusion, local irradiation of liver allografts can be a useful adjunct in patients for whom conventional options have been exhausted or cannot be used. The ability of LAI to reverse allograft dysfunction and promote patient survival appears to be greatest before the onset of severe cholestatic injury.

Alcohol abuse in deceased liver donors: impact on post-transplant outcomes

BACKGROUND

Many deceased liver donors with a history of alcohol abuse are excluded based upon medical history alone. This paper summarizes the transplant outcomes for a large number of deceased liver donors with a documented history of alcohol abuse.

METHODS

The records for 1478 consecutive deceased liver donors were reviewed (2001-2012). As per the United Network for Organ Sharing criteria, heavy alcohol use by an organ donor is defined as chronic intake of two or more drinks per day. Donors with a documented history of alcohol abuse were divided into three groups according to duration of abuse (<10 years, 10-24 years and 25 + years). Reperfusion biopsies are reported. Outcomes include biopsy appearance, early graft function and early and late graft survival.

RESULTS

There were 161 donors with alcohol abuse: <10 years (29%); 10-24 years (42%); and ≥25 years (29%). Risk of 90-day graft loss for these three groups was: 0%, 3% and 2%, compared to 3% for all other donors (P = 0.62). Graft survival at 1 year for donor grafts with and without alcohol abuse was 89% and 87% (P = 0.52). There was no difference in early graft function. Cox proportional hazards modelling for graft survival demonstrates no statistically significant difference in survival up to 10 years post-transplant.

CONCLUSIONS

This study demonstrates successful transplantation of a large number of deceased donor liver grafts from donors with a documented history of alcohol abuse (n = 161; 11% of all grafts). These extended criteria donor allografts may, therefore, be utilized successfully with similar outcomes.

Impact of anti-thymocyte globulin during immunosuppression induction in patients with hepatitis C after liver transplantation

BACKGROUND

Induction immunosuppression with anti-thymocyte globulin (ATG) provides potential benefits after liver transplantation (LT). However, its use in patients with LT and hepatitis C (HCV) is controversial.

AIM

To evaluate the 1- and 2-year patient survival and HCV recurrence rate in patients receiving ATG during the induction phase of immunosuppression (IPI) after LT.

METHODS

A total of 49 patients undergoing their first LT for HCV were randomized to receive ATG during IPI. Patient survival and HCV recurrence were determined at 1 and 2 years. The frequency of acute cellular rejection (ACR), infections, and neoplasms was also evaluated.

RESULTS

Twenty-six patients were randomized to receive ATG (Arm-1) and 23 to standard induction therapy (Arm-2). Those given ATG had lower HCV recurrence (26.9 vs 73.9 %, p = 0.001). The 1- and 2-year patient survival rates were similar for both arms (p = 0.33). Infections occurred in 46.1 % subjects in Arm-1 and 34.7 % in Arm-2 (p = 0.562). There was a greater proportion of fungal infections in Arm-1 (19.2 vs 0 %, p = 0.032).

CONCLUSIONS

ATG during the IPI was associated with lower frequency of recurrence of HCV in patients undergoing LT. This, however, did not affect the 1- and 2-year survival and the frequency of ACR, infections, or neoplasms.

Mammalian target of rapamycin inhibitors are associated with lower rates of hepatocellular carcinoma recurrence after liver transplantation: a systematic review

Calcineurin inhibitors (CNIs) have been associated in a dose-dependent fashion with an increased risk of post-transplant hepatocellular carcinoma (HCC) recurrence. The mammalian target of rapamycin inhibitors (mTORi) (sirolimus/everolimus) might represent an alternative immunosuppressive regimen with antineoplastic effect. In the present systematic review, the association between mTORi and HCC recurrence after liver transplantation (LT) was evaluated and compared against that of CNIs-treated patients. In total, 3666 HCC liver transplant recipients from 42 studies met the inclusion criteria. Patients under CNIs developed HCC recurrence significantly more frequently, compared with patients under mTORi (448/3227 or 13.8% vs. 35/439 or 8%, P < 0.001), although patients treated with CNIs had a higher proportion of HCC within Milan criteria (74% vs. 69%) and lower rates of microvascular invasion, compared with mTORi-treated patients (22% vs. 44%) (P < 0.05). Patients on everolimus had significantly lower recurrence rates of HCC, compared with those on sirolimus or CNIs (4.1% vs. 10.5% vs. 13.8%, respectively, P < 0.05), but everolimus-treated recipients had shorter follow-up period (13 vs. 30 vs. 43.2 months, respectively) and more frequently been transplanted for HCC within Milan criteria (84% vs. 60.5% vs. 74%, respectively, P < 0.05). Our findings favor the use of mTORi instead of CNIs to control HCC recurrence after LT, but comparative studies with longer follow-up are needed for final conclusions.

Peritransplant lymphopenia is a novel prognostic factor in recurrence of hepatocellular carcinoma after liver transplantation

BACKGROUND

Absolute lymphocyte count (ALC) is considered a surrogate marker for the level of immunosuppression and nutritional status of patients and a prognostic factor for survival and recurrence in several cancers. The aim of this study was to investigate the prognostic value of peritransplant ALC for the recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT).

METHODS

HCC patients who underwent LT between 2000 and 2010 were evaluated. Exclusion criteria were combined HCC and cholangiocarcinoma. Peritransplant ALCs (before LT and 2 weeks and 1 month after LT) were analyzed along with tumor, operative, and donor characteristics to identify risk factors for the recurrence of HCC.

RESULTS

HCC developed in 27 of the 173 LT patients investigated for risk factors (15.6%). The median time to recurrence was 1.14 years. Low ALCs before and after LT were associated with a higher recurrence rate in a continuous manner (before LT: hazard ratio=1.12, P=0.003; 2 weeks after LT: hazard ratio=1.14, P=0.008; 1 month after LT: hazard ratio=1.06, P=0.055) (increased risk per 100/μL down). On multivariate Cox regression analysis, peritransplant persistent lymphopenia (<1000/μL before LT and <500/μL at 2 weeks and 1 month after LT) was an independent risk factor for cancer recurrence (hazard ratio=7.05, P<0.001), along with tumor characteristics.

CONCLUSION

Peritransplant lymphopenia is a powerful prognostic factor for the recurrence of HCC after LT, which suggests that maintaining ALCs in LT patients might improve cancer outcome.

Current strategies for immunosuppression following liver transplantation

BACKGROUND

New strategies for immunosuppression (IS) after liver transplantation (LTx) are in part responsible for the increased patient and graft survival seen over time. With a few basic exceptions-notably the continued use of steroids and calcineurin inhibitors (CNIs)-IS drugs and regimens being used today are different from those used 30 years ago. While graft loss due to acute or chronic rejection has become rare, the side effect burden of IS drugs exerts a significant toll on patients.

CONCEPTS/TRENDS

CNIs continue to form the backbone of IS regimens, although their use is hampered by nephrotoxicity and other adverse effects. Consequently, a variety of CNI reduction or withdrawal strategies have formed the basis of clinical trials or entered into clinical practice. These trials have included the use of everolimus, an mTOR inhibitor, and anti-interleukin-2 receptor antibodies. Basiliximab, as well as other lymphocyte nondepleting and depleting agents, have shown benefit in induction regimens.

SUMMARY

Along with steroid reduction or elimination, current strategies for IS after LTx continue to explore novel combinations of agents, with an aim toward striking a balance between diminution of rejection and the need for avoiding adverse effects of the IS drugs. Long-term maintenance strategies are also discussed in this review, as is development of tolerance and antibody-mediated rejection.

Role of steroid minimization in the tacrolimus-based immunosuppressive regimen for liver transplant recipients: a systematic review and meta-analysis of prospective randomized controlled trials

To evaluate the efficacy and safety of early steroid withdrawal or steroid avoidance in the tacrolimus (Tac)-based immunosuppressive regimen for liver transplant recipients. According to the requirements of the Cochrane systematic review, a thorough literature search was performed in the PubMed/MEDLINE and Cochrane electronic databases between 1995 and 2011 using the key words "liver transplantation," "Tac," and "steroid free" or "steroid withdrawal," restricting articles to the English language. Data were processed for a meta-analysis by Stata 12 software. Altogether 17 prospective randomized controlled trials containing 1,980 transplanted patients were included in this study. The overall pooled RR estimates of 1-, 2-, 3-, and 5-year patient and graft survival rates were 0.985, 0.998, 0.995, and 1.100 (95 % CI 0.925-1.048, 0.934-1.067, 0.894-1.107, and 0.968-1.250, respectively), as well as 0.998, 0.993, 0.945, and 1.053, respectively (95 % CI 0.928-1.072, 0.902-1.092, 0.833-1.072, and 0.849-1.307, respectively). The other pooled RR estimates of acute rejection and chronic rejection rates for all enrolled studies were 1.077 and 0.311 (95 % CI 0.864-1.343 and 0.003-37.207). As for secondary predictors, the pooled RR estimates such as HCV recurrence, HCC recurrence, diabetes, hypertension, kidney dysfunction, bacterial infection, and CMV were 1.101, 1.403, 1.836, 1.607, 0.842, 1.096, and 2.280, respectively (95 % CI 0.964-1.257, 0.422-4.688, 1.294-2.606, 0.926-1.228, 0.693-1.022, 0.783-1.533, and 1.500-3.465, respectively). There were no differences between the steroid group and steroid-free group for all clinical observational indices except for the incidence of diabetes (p = 0.001) and CMV infection (p < 0.001). In summary, our study indicate that rapid discontinuation of steroid in the Tac-based immunosuppressive regimen may not lead to an increased risk of morbidity and rejection rate.

Excessive immunosuppression as a potential cause of poor survival in simultaneous liver/kidney transplantation for hepatitis C

Appropriate recipient selection of simultaneous liver/kidney transplantation (SLKT) remains controversial. In particular, data on liver graft survival in hepatitis C virus-infected (HCV+) SLKT recipients are lacking. We conducted a single-center, retrospective study of HCV+ SLKT recipients (N = 25) in comparison with HCV- SLKT (N = 26) and HCV+ liver transplantation alone (LTA, N = 296). Despite backgrounds of HCV+ and HCV- SLKT being similar, HCV+ SLKT demonstrated significantly impaired 5-year liver graft survival of 35% (HCV- SLKT, 79%, P = 0.004). Compared with HCV+ LTA, induction immunosuppression was more frequently used in HCV+ SLKT. Five-year liver graft survival rate for HCV+ SLKT was significantly lower than that for LTA (35% vs. 74%, respectively, P < 0.001). Adjusted hazard ratio of liver graft loss in HCV+ SLKT was 4.9 (95% confidence interval 2.0-12.1, P = 0.001). HCV+ SLKT recipients were more likely to succumb to recurrent HCV and sepsis compared with LTA (32% vs. 8.8%, P < 0.001 and 24% vs. 8.8%, P = 0.030, respectively). Ten HCV+ SLKT recipients underwent anti-HCV therapy for recurrent HCV; only 1 achieved sustained virological response. HCV+ SLKT is associated with significantly decreased long-term prognosis compared with HCV- SLKT and HCV+ LTA.

Crossmatch-positive liver transplantation in patients receiving thymoglobulin-rituximab induction

BACKGROUND

Positive crossmatch (CM) in liver transplantation (LT) is associated with worse outcomes. Role of induction immunosuppression in this setting remains to be studied.

METHODS

One thousand consecutive LT patients receiving rabbit antithymocyte globulin±rituximab induction were studied. Pretransplantation sera of 55 CM-positive (CM) patients were tested for C1q-fixing donor-specific antibodies (DSA). Diagnosis of antibody-mediated rejection required presence of diffuse vascular C4d expression on liver biopsies.

RESULTS

CM was positive in 112 (11%) recipients. Antibody-mediated rejection was observed in 3 (0.03%) patients, whereas acute cellular rejection (ACR) occurred in 31 (3%) patients. CM status was associated with a higher incidence of ACR (9% in CM vs. 2% in CM-negative [CM]; P<0.01) and chronic rejection (4% in CM vs. 1% in CM; P<0.01). Graft survival was slightly lower in CM patients (at 1 year; 85% in CM vs. 89% in CM; P=0.26). Patients with autoimmune hepatitis, primary sclerosing cholangitis, and primary biliary cirrhosis as a group had a tendency toward CM status as well as developing ACR. Upon multivariate analysis, CM status was the strongest predictor of ACR (B=1.14; P=0.02). Only half of CM patients harbored C1q-fixing DSA. Presence of C1q-fixing DSA was not associated with increased incidence of ACR.

CONCLUSIONS

In LT, CM status is associated with an increased incidence of acute rejection, chronic rejection, and slightly worse graft survival. With the use of rabbit antithymocyte globulin±rituximab induction, overall low rejection rates can be achieved in CM LT.

Impact of positive flow cytometry crossmatch on outcomes of intestinal/multivisceral transplantation: role anti-IL-2 receptor antibody

BACKGROUND

Positive crossmatch may be associated with an increased risk of acute rejection (AR) and worse overall outcomes after intestinal/multivisceral (MV) transplantation. However, the evidence from published studies in this setting is sparse and contradictory. This study reports the impact of positive flow cytometry crossmatch on clinical outcomes after intestinal/MV transplantation and the use of anti-interleukin (IL)-2 receptor antibody as a maintenance immunosuppressant.

METHODS

Records of all intestinal/MV transplants from 2003 to 2010 were reviewed. Flow cytometry was used to evaluate T- and B-cell crossmatch status. Standard immunosuppression included rabbit anti-thymocyte globulin-rituximab induction with tacrolimus and steroid maintenance. From 2008 onwards (second era), monthly anti-IL-2 receptor antibody was added to the maintenance immunosuppression in patients receiving liver-excluding transplants.

RESULTS

Of 131 intestinal/MV transplants, 27 (21%) had a positive crossmatch. Positive crossmatch was not associated with an increased incidence of AR and graft loss (30% and 37% vs. 29% and 47%; P=0.94 and 0.35, respectively). This effect was maintained in liver-excluding transplants. Overall rate of AR decreased from 39% to 22% in the second era. In liver-excluding transplants, there was a significant decrease in AR from 75% to 44% with the use of anti-IL-2 receptor antibody therapy.

CONCLUSIONS

With rabbit anti-thymocyte globulin-rituximab induction, positive crossmatch status is not associated with worse outcomes after intestinal/MV transplantation. Use of anti-IL-2 receptor antibody as a part of maintenance immunosuppression may be beneficial in liver-excluding transplants.

Immunomodulating options for liver transplant patients

Much has changed since the early years of liver transplantation. Improvements in post-transplant survival are largely due to more selective and less toxic immunosuppression regimens and advances in operative and perioperative care. This has allowed liver transplantation to become an extremely successful treatment option for patients with endstage liver disease. Beginning with cyclosporine, a cyclic endecapeptide of fungal origin and the first of the calcineurin inhibitors to find widespread use, immunosuppressive regimens have evolved to include additional calcineurin inhibitors, steroids, mTOR inhibitors, antimetabolites and antibodies, mostly targeting T-cell activation. This review will present currently available immunosuppressive agents used in the perioperative period of liver transplantation, as well as maintenance treatments, tailoring therapeutic strategies for specific populations, and advances in immune monitoring and tolerance.