Vibration Controlled Transient Elastography Based Parameters Predicts Clinical Outcomes in Liver Transplant Recipients.

BACKGROUND & AIMS: Vibration-controlled transient elastography (VCTE) is used in clinical practice to risk stratify liver transplant (LT) recipients, however, there is currently little data demonstrating the relationship between VCTE and clinical outcomes. METHODS: 362 adult LT recipients with successful VCTE examination between 2015 and 2022 were included. Presence of advanced fibrosis was defined as liver stiffness measurement (LSM) ≥10.5kPa and hepatic steatosis as controlled attenuation parameter (CAP)≥ 270 dB/m. The outcomes of interest included all-cause mortality, myocardial infarction (MI), and graft cirrhosis using cumulative incidence analysis that accounted for the competing risks of these outcomes. RESULTS: The LSM was elevated in 64 (18%) and CAP in 163 (45%) of LT recipients. The baseline LSM values were similar in patients with elevated vs. normal CAP values. After a median follow up of 65 (IQR 20, 140) months from LT to baseline VCTE, 66 (18%) of patients died, 12 (3%) developed graft cirrhosis, and 18 (5%) experienced an MI. Baseline high LSM was independently associated with all-cause mortality (HR 1.97, 95% CI 1.11, 3.50, p=0.02) and new onset cirrhosis (HR 6.74, 95% CI 2.08, 21.79, p<0.01). A higher CAP value was significantly and independently associated with increased risk of experiencing a MI over study follow up with HR 4.14 [95% CI 1.29, 13.27, p=0.017]. CONCLUSIONS: The VCTE based parameters are associated with clinical outcomes and offer the potential to be incorporated into clinical risk stratification strategies to improve outcomes among LT recipients.

Burden of Portal Hypertension Complications Is Greater in Liver Transplant Wait-Listed Registrants with End-Stage Liver Disease and Type 2 Diabetes.

BACKGROUND AND AIMS: Impact of type 2 diabetes mellitus (T2DM) in patients with end-stage liver disease (ESLD) awaiting liver transplantation (LT) remains poorly defined. The objective of the present study is to evaluate the relationship between T2DM and clinical outcomes among patients with LT waitlist registrants. We hypothesize that the presence of T2DM will be associated with worse clinical outcomes. METHODS: 593 patients adult (age 18 years or older) who were registered for LT between 1/2010 and 1/2017 were included in this retrospective analysis. The impact of T2DM on liver-associated clinical events (LACE), survival, hospitalizations, need for renal replacement therapy, and likelihood of receiving LT were evaluated over a 12-month period. LACE was defined as variceal hemorrhage, hepatic encephalopathy, and ascites. Kaplan-Meier and Cox regression analysis were used to determine the association between T2DM and clinical outcomes. RESULTS: The baseline prevalence of T2DM was 32% (n = 191) and patients with T2DM were more likely to have esophageal varices (61% vs. 47%, p = 0.002) and history of variceal hemorrhage (23% vs. 16%, p = 0.03). The presence of T2DM was associated with increased risk of incident ascites (HR 1.91, 95% CI 1.11, 3.28, p = 0.019). Patients with T2DM were more likely to require hospitalizations (56% vs. 49%, p = 0.06), hospitalized with portal hypertension-related complications (22% vs. 14%; p = 0.026), and require renal replacement therapy during their hospitalization. Patients with T2DM were less likely to receive a LT (37% vs. 45%; p = 0.03). Regarding MELD labs, patients with T2DM had significantly lower bilirubin at each follow-up; however, no differences in INR and creatinine were noted. CONCLUSION: Patients with T2DM are at increased risk of clinical outcomes. This risk is not captured in MELD score, which may potentially negatively affect their likelihood of receiving LT.

Cost minimization analysis of short-duration antiviral prophylaxis for hepatitis C positive donor kidney transplants.

BACKGROUND: Trials describing 4-12 week courses of direct-acting antiviral drugs (DAAs) to treat hepatitis C virus (HCV) transmission from infected donors to uninfected kidney transplant recipients (D+/R-transplants), may be limited in application by costs and delayed access to expensive DAAs. A short prophylactic strategy may be safer and cost-effective. Here, we report a cost minimization analysis using the health system perspective to determine the least expensive DAA regimen, using available published strategies. OBJECTIVES: To conduct cost-minimization analyses (CMAs) from the health system perspective of four DAA regimens to prevent and/or treat HCV transmission from D+/R-kidney transplants. METHODS: CMAs comparing 4 strategies: 1) 7-day prophylaxis with generic sofosbuvir/velpatasvir (SOF/VEL), with 12-week branded glecaprevir/pibrentasvir (G/P) for those with transmission; 2) 8-day branded G/P prophylaxis, with 12-week branded SOF/VEL/voxilaprevir for those with transmission; 3) 4-week perioperative generic SOF/VEL prophylaxis, with 12-week branded G/P for those with transmission; and 4) 8-week branded G/P "transmit-and-treat." We included data from published literature to estimate the probability of viral transmission in patients who received DAA prophylaxis, and assumed a 100% transmission rate for those who received the "transmit-and-treat" approach. RESULTS: In base-case analyses, strategies 1 (expected cost [EC]: $2326) and 2 (expected cost: $2646) were less expensive than strategies 3 (EC: $4859) and 4 (EC: $18,525). Threshold analyses for 7-day SOF/VEL versus 8-day G/P suggested that there were reasonable input levels at which the 8-day strategy may be least costly. The threshold values for the SOF/VEL prophylaxis strategies (7-day vs. 4- week) indicated that the 4-week strategy is unlikely to be less costly under any reasonable value of the input variables. CONCLUSIONS: Short duration DAA prophylaxis using 7 days of SOF/VEL or 8 days of G/P has the potential to yield significant cost savings for D+/R- kidney transplants.

Use of belatacept in kidney transplantation: what's new?

PURPOSE OF REVIEW: The advent of calcineurin inhibitors have led to a significant improvement in short term outcomes after kidney transplantation. However, long term outcomes are hindered by the cardiovascular, metabolic and chronic renal toxicity associated with these agents. Belatacept is a selective T cell costimulation blocker that is approved for prevention of rejection in kidney transplantation, and has been associated with favorable cardiovascular, metabolic and renal outcomes in kidney transplant recipients. This review provides an overview of recent updates in the use of belatacept in kidney transplant recipients. RECENT FINDINGS: Belatacept may be a safe alternative to calcineurin inhibitors for select kidney transplant populations. Patients converted to belatacept from a calcineurin inhibitor-based immunosuppression generally experience improvement in renal function, and may be less likely to develop de novo donor specific antibodies or new onset diabetes after transplantation. Although, belatacept based immunosuppression may increase the risk of early acute cellular rejection, it may however be beneficial in stabilization of long-term renal function and improvement in inflammation in patients with chronic active antibody mediated rejection. These benefits need to be counterweighed with risks of lack of response to severe acute respiratory syndrome coronavirus 2 vaccination and other adverse infectious outcomes. SUMMARY: Belatacept may be an alternative to calcineurin inhibitors and may contribute to improved long term metabolic and allograft outcomes in kidney transplant recipients. Careful selection of patients for belatacept-based immunosuppression is needed, to obviate the risk of acute rejection shown in clinical studies.

Outcomes of short-duration antiviral prophylaxis for hepatitis C positive donor kidney transplants.

Trials describing 4- to 12-week courses of direct-acting antiviral drugs (DAAs) to treat hepatitis C virus (HCV) transmission from infected donors to uninfected kidney transplant recipients (D+/R- transplants) may be limited in "real-world" application by costs and delayed access to DAAs. We previously reported HCV transmission of 13% among D+/R- transplants with 2- to 4-day pangenotypic sofosbuvir/velpatasvir (SOF/VEL) perioperative prophylaxis, where one patient with HCV transmission was a nonresponder to first-line full-course DAA. Here, we report new data with a 7-day prophylaxis protocol (N = 50), as well as cumulative treatment and outcome data on all HCV D+/R- transplants (N = 102). Overall, nine patients (9/102; 9%; 95% CI: 5%-16%) developed HCV transmission, with a significant decline noted in the 7-day group (2/50; 4%; 95% CI: 0%-13%) compared with 2- to 4-day prophylaxis (7/52; 13%; 95% CI: 5%-25%). All patients with HCV transmission achieved sustained virologic response post full-course therapy (including one nonresponder from initial trial). A 1:1 matched analysis (N = 102) with contemporary HCV D-/R- transplants (controls) showed that although the pretransplant wait time was significantly shorter for D+/R- compared with D-/R- (mean: 1.8 vs. 4.4 years; p < .001), there were no differences in infections, rejection, development of de novo donor-specific antibody, or transplant outcomes up to 6 months of transplant.

Early initiation of sodium-glucose linked transporter inhibitors (SGLT-2i) and associated metabolic and electrolyte outcomes in diabetic kidney transplant recipients.

There is a paucity of data on the use of SGLT2 inhibitors on outcomes in kidney transplant recipients. There may be concern in initiating these agents, especially within the first year post-transplant when renal function is more labile and immunosuppression more intense, due to a presumed high risk of urinary infections and acute kidney injury. This is a retrospective study on 50 kidney transplant recipients, half of whom were started on therapy within the first year of transplant. Over a follow-up period of 6 months, overall patients had a statistically significant improvement in weight by -2.95 kg [SD 3.54, P = <.0001 (CI: 3.53, 1.50)] as well as hypomagnesemia 0.13 [SD 1.73, P = .0004 (CI: 0.06, 0.20)]. Overall insulin usage declined by -3.7 units [SD 22.8, P = .17]. 14% of patients had at least one urinary tract infection although this rate is not different (~20%) than that reported historically in this high-risk population.

Letermovir prophylaxis in solid organ transplant-Assessing CMV breakthrough and tacrolimus drug interaction.

BACKGROUND: Valganciclovir is the preferred drug for cytomegalovirus (CMV) prophylaxis in solid organ transplantation. A limitation to its use is profound myelosuppression. Letermovir is a new agent approved for CMV prophylaxis in hematopoietic stem cell transplantation and is associated with less toxicity. This study aims to assess the effectiveness and safety of letermovir in solid organ transplantation. METHODS: A single-center, matched cohort study was performed on 31 transplant recipients who were converted from valganciclovir to letermovir from November 2017 to June 2020. The primary outcome was the rate of CMV breakthrough infections while on prophylaxis. Secondary outcomes included rate of leukopenia, doses of immunosuppression, rejection, non-CMV infection, and renal function. Statistical analyses of continuous variables included the student's t-test, ANOVA test, and Wilcoxon Signed Rank test. Categorical data were analyzed with chi-square test and Fisher's Exact test. RESULTS: There was no difference in the rate of CMV breakthrough between patients on letermovir (8.7%) and valganciclovir (13.5%), (P = .7097). After conversion to letermovir, patients required lower tacrolimus doses at -3.34 mg (SD-1.3, P = .0273), between conversion and day 7. Transplant Infectious Disease The median difference in tacrolimus trough concentrations from conversion to day seven was 9.1 ng/ml [4.9, 16.95] (P = .0002). Leukopenia improved by 1.8 109/L [1.08, 4.85] (P < .0001). CONCLUSIONS: Patients converted from valganciclovir to letermovir did not show an increased rate of CMV breakthrough compared to a historical, matched cohort of patients remaining on valganciclovir. A significant drug interaction was noted with tacrolimus, leading to a recommendation to reduce the dose by 40-50% upon initiation of letermovir.

Impact of Belatacept Conversion on Renal Function, Histology, and Gene Expression in Kidney Transplant Patients With Chronic Active Antibody-mediated Rejection.

BACKGROUND: Here, we present our initial experience with a prospective protocol of belatacept conversion in patients with chronic active antibody-mediated rejection (caAMR) and a high degree of chronicity at the time of diagnosis. METHODS: We converted 19 patients (mean age, 45 ± 12 y) with biopsy-proven caAMR from tacrolimus to belatacept at a median of 44 months post-kidney transplant. RESULTS: At a median of 29 months (interquartile range, 16-46 mo) postconversion, death-censored graft and patient survivals were 89% and 95%, respectively. When compared to a 1:2 propensity-matched control cohort from the INSERM U970 registry maintained on calcineurin inhibitor, the belatacept group had progressive improvement (P = 0.02) in estimated glomerular filtration rate from a mean of 33.9 ± 10 at baseline to 37.8 ± 13 at 6 months and 38.5 ± 12 mL/min/1.73 m2 at 12 months postconversion, as compared to a steady decline noted in the controls (36.2 [baseline] → 33.1 [6 mo] → 32.7 mL/min/1.73 m2 [12 mo] of follow-up). A paired histologic comparison of preconversion and postconversion (performed at median 9.5 mo postconversion) biopsies showed no worsening in microvascular inflammation or chronicity. The paired tissue gene expression analysis showed improved mean total rejection score (0.68 ± 0.26-0.56 ± 0.33; P = 0.02) and a trend toward improved antibody-mediated rejection score (0.64 ± 0.34-0.56 ± 0.39; P = 0.06). CONCLUSIONS: Here, we report that in patients diagnosed with caAMR who were not subjected to intensive salvage immunosuppressive therapies, isolated belatacept conversion alone was associated with stabilization in renal function. These results are bolstered by molecular evidence of improved inflammation.

Comparison of Alemtuzumab Versus Basiliximab Induction Therapy in Elderly Kidney Transplant Recipients: A Single-Center Experience.

BACKGROUND: The optimal choice of induction immunosuppression for elderly kidney transplant recipients remains unclear. Although alemtuzumab has been associated with escalating risk of death and graft loss in this population, this risk has not been adequately explored. The purpose of this study was to compare the safety and efficacy of alemtuzumab with basiliximab induction in this population. METHODS: This is a retrospective matched cohort study of kidney transplant recipients aged ≥65 years. Patients who received alemtuzumab induction were matched (1:2) to a basiliximab control. The primary outcome was allograft survival. The incidence of acute rejection, infection, and all-cause mortality was measured. RESULTS: Fifty-one and 102 patients were included in the alemtuzumab and basiliximab groups, respectively. Baseline demographics were similar between groups, except for more living donor transplant recipients in the alemtuzumab group (26/51 [51%] vs 31/102 [30.4%], P = .02). Acute cellular rejection occurred more frequently within the first year in the basiliximab group (P = .02). There was no difference in rates of infection within the first year. Graft and patient survival rates were similar over the follow-up period. Patients receiving basiliximab had a higher glomerular filtration rate at 2 years posttransplant (59 mL/min/1.73 m2 vs 49 mL/min/1.73 m2, P = .03). CONCLUSIONS: Alemtuzumab induction is associated with similar outcomes to basiliximab in elderly kidney transplant recipients.

COVID-19 in Kidney Transplantation: Epidemiology, Management Considerations, and the Impact on Kidney Transplant Practice.

The novel severe acute respiratory syndrome coronavirus 2 was identified in the late 2019 as the cause of coronavirus disease 2019 (COVID-19), an acute respiratory viral illness. Patients with chronic underlying conditions may have an increased risk of morbidity and mortality from COVID-19. Kidney transplant recipients may be at a uniquely increased risk of serious complications from COVID-19 as compared to the general population because of a chronically immunosuppressed state and a high prevalence of comorbidities like diabetes, heart disease, and lung disease. Early data suggest that the mortality of patients on dialysis may be comparable to those with kidney transplants, although more research is needed. This concise review aims to describe the epidemiology of COVID-19 in kidney transplant recipients, manifestations, appropriate management, and clinical outcomes based on the available literature. Current evidence on many of the specific antiviral measures against COVID-19 has not shown a clear-cut benefit in smaller studies and the results of several ongoing larger clinical trials are awaited. In addition, we also highlight the impact of COVID-19 on kidney transplant center practice and volumes; potential living or deceased donors, recipients; and induction immunosuppression and surgical strategies.

Impact of belatacept conversion on kidney transplant function, histology, and gene expression - a single-center study.

Prior studies on belatacept conversion from calcineurin inhibitor (CNI) have been limited by an absence of postconversion surveillance biopsies that could underestimate subclinical rejection, or a case-controlled design. A total of 53 adult patients with allograft dysfunction underwent belatacept conversion (median: 6 months) post-transplant. At a median follow-up = 2.5 years, patient survival was 94% with a death-censored graft survival of 85%. Seven (13%) patients had acute rejection (including 3 subclinical) at median 6 months postconversion. Overall, eGFR improved (P = <0.001) from baseline = 31±15 to 40.2 ± 17.6 ml/min/1.73m2 by 6 months postconversion, but then stayed stable. This improvement was also observed (P < 0.001) in comparison with a propensity matched control cohort on CNI, where eGFR stayed stable (mean ~ 32ml/min/1.72m2 ) over 2-year follow-up. Patients converted < 6 months post-transplant were more likely to have a long-term improvement in kidney function. Paired gene expression analysis of 30 (of 53) consecutive pre- and postconversion surveillance biopsies did not reveal changes in inflammation/acute injury; although atrophy-fibrosis score worsened (mean = 0.28 to 0.44; P = 0.005). Thus, improvement in renal function with belatacept conversion occurred early and then sustained in comparison with controls where renal function remained unchanged overtime. We were unable to show molecular signals that could be related to CNI administration and regressed after withdrawal.

Lack of Histological and Molecular Signature Response to Tocilizumab in Kidney Transplants with Chronic Active Antibody Mediated Rejection: A Case Series.

Background: Traditional therapies for caAbMR have unclear efficacy with significant side effects in recipients of kidney transplants (KTs). A recent single-center case series suggested tocilizumab (TCZ) could stabilize renal function and improve microvascular inflammation. Here we report our findings of the use of TCZ in patients with caAbMR. Methods: Ten adult recipients of KTs with biopsy-proven caAbMR were treated with TCZ at 8 mg/kg per month. Patients were monitored for adverse events, and therapy was interrupted in the setting of serious infections. Six patients (60%) underwent post-treatment biopsies. Results: Patients (mean age of 43 years) were initiated on TCZ at a median of 36 months post-KT. A majority of patients were black (70%), underwent regrafts (40%), and were sensitized (mean cPRA=41%). Patients received a median of six doses of TCZ (range=3-10). At a median follow-up of 12 months (range=8-24 months), renal function did not show improvement (mean eGFR, 42±18 ml/min per 1.73 m2 to 37±24 ml/min per 1.73 m2; P=0.27). The slope of decline in eGFR remained unchanged (-0.14±0.9 to -0.33±1.1; P=0.25). There was no improvement in mean MVI (g+ptc) (4.8±1.4 to 4.2±2.0; P=0.39) scores or Molecular Microscope Diagnostic System (MMDx) AbMR scores (0.79±0.17 to 0.78±0.26; P=0.86). There was a numeric worsening of chronicity (ci+ct) scores (2.5±0.8 to 3.3±1.7; P=0.38) and MMDx atrophy fibrosis scores (0.36±0.24 to 0.58±0.15; P=0.21). Patient survival was 90%, with one patient death due to complications from a hip infection. Overall death-censored graft survival was 80%, with two graft losses in patients who had recurrent infections requiring hospitalization. Conclusions: In this early experience, we report a lack of efficacy and toxicity with the use of TCZ for caAbMR. Prospective clinical trials are needed to clarify the role of IL-6 blockade and the possibility of increased incidence of infections in patients with caAbMR who are treated with TCZ.

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.

Ultra-short duration direct acting antiviral prophylaxis to prevent virus transmission from hepatitis C viremic donors to hepatitis C negative kidney transplant recipients.

We conducted an adaptive design single-center pilot trial between October 2017 and November 2018 to determine the safety and efficacy of ultra-short-term perioperative pangenotypic direct acting antiviral (DAA) prophylaxis for deceased hepatitis C virus (HCV)-nucleic acid test (NAT) positive donors to HCV negative kidney recipients (D+/R-). In Group 1, 10 patients received one dose of SOF/VEL (sofusbuvir/velpatasvir) pretransplant and one dose on posttransplant Day 1. In Group 2A (N = 15) and the posttrial validation (Group 2B; N = 25) phase, patients received two additional SOF/VEL doses (total 4) on Days 2 and 3 posttransplant. Development of posttransplant HCV transmission triggered 12-week DAA therapy. For available donor samples (N = 27), median donor viral load was 1.37E + 06 IU/mL (genotype [GT]1a: 70%; GT2: 7%; GT3: 23%). Overall viral transmission rate was 12% (6/50; Group 1:30% [3/10]; Group 2A:13% [2/15]; Group 2B:4% [1/25]). For the 6 viremic patients, 5 (83%) achieved sustained virologic response (3 with first-line DAA therapy; and two after retreatment with second-line DAA). At a median follow-up of 8 months posttransplant, overall patient and allograft survivals were 98%, respectively. The 4-day strategy reduced viral transmission to 7.5% (3/40; 95% confidence interval [CI]: 1.8%-20.5%) and could result in avoidance of prolonged posttransplant DAA therapy for most D+/R - transplants.