Faculty Bibliography

BACKGROUND:Optimizing antithymocyte globulin (ATG) dosage is critical, particularly for high-risk kidney transplant (KT) recipients without cytomegalovirus (CMV) prophylaxis. METHODS:We studied 630 KT recipients with expanded criteria donors or panel reactive antibody ≥50% at Hospital do Rim, Brazil (January 1, 2013 to May 21, 2015) to determine whether a single ATG dose was safe and effective in patients without CMV prophylaxis. Patients received ≥4 doses (1-1.5 mg/kg/per dose) until June 17, 2014, when the induction protocol changed to a single ATG dose (3 mg/kg). We used Cox regression to compare the risk of CMV infection and acute rejection (AR) among KT recipients by ATG dose. RESULTS:Adjusting for clinical and transplant factors, a single ATG dose was associated with a lower risk of CMV infection (adjusted hazard ratio [aHR]: 0.63; 95% confidence interval [CI], 0.42-0.93; P = 0.02) and a similar risk of AR (aHR: 1.16; 95% CI, 0.47-2.83; P = 0.8), compared to multiple doses. We found no differences in death-censored graft loss (5.0% versus 4.8%, aHR: 1.06; 95% CI, 0.51-2.23; P = 0.9) or mortality (4.7% versus 3.4%; aHR: 1.42; 95% CI, 0.62-3.24; P = 0.4) at 1-year post-KT by ATG dose. CONCLUSIONS:In our study of high-risk KT recipients without CMV prophylaxis, a single ATG dose decreased the risk of CMV infection without increasing the risk of AR or compromising graft or patient survival.

Optimization of maintenance immunosuppression (mIS) regimens in the transplant recipient requires a balance between sufficient potency to prevent rejection and avoidance of excessive immunosuppression to prevent toxicities and complications. The optimal regimen after simultaneous liver-kidney (SLK) transplantation remains unclear, but small single-center reports have shown success with steroid-sparing regimens. We studied 4184 adult SLK recipients using the Scientific Registry of Transplant Recipients, from March 1, 2002, to February 28, 2017, on tacrolimus-based regimens at 1 year post-transplant. We determined the association between mIS regimen and mortality and graft failure using Cox proportional hazard models. The use of steroid-sparing regimens increased post-transplant, from 16.1% at discharge to 88.0% at 5 years. Using multi-level logistic regression modeling, we found center-level variation to be the major contributor to choice of mIS regimen (ICC 44.5%; 95% CI: 36.2%-53.0%). In multivariate analysis, use of a steroid-sparing regimen at 1 year was associated with a 21% decreased risk of mortality compared to steroid-containing regimens (aHR 0.79, P = .01) and 20% decreased risk of liver graft failure (aHR 0.80, P = .01), without differences in kidney graft loss risk (aHR 0.92, P = .6). Among SLK recipients, the use of a steroid-sparing regimen appears to be safe and effective without adverse effects on patient or graft survival.

In March 2020, COVID-19 infections began to rise exponentially in the United States, placing substantial burden on the healthcare system. As a result, there was a rapid change in transplant practices and policies, with cessation of most procedures. Our goal was to understand changes to pediatric kidney transplantation (KT) at the national level during the COVID-19 epidemic. Using SRTR data, we examined changes in pediatric waitlist registration, waitlist removal or inactivation, and deceased donor and living donor (DDKT/LDKT) events during the start of the disease transmission in the United States compared to the same time the previous year. We saw an initial decrease in DDKT and LDKT by 47% and 82% compared to expected events and then a continual increase, with numbers reaching expected pre-pandemic levels by May 2020. In the early phase of the pandemic, waitlist inactivation and removals due to death or deteriorating condition rose above expected values by 152% and 189%, respectively. There was a statistically significant decrease in new waitlist additions (IRR _0.49 0.65 _0.85 ) and LDKT (IRR _0.17 0.38 _0.84 ) _{in states with high vs low COVID activity. Transplant recipients during the pandemic were more likely to have received a DDKT, but had similar cPRA, waitlist time and cause of ESRD as before the pandemic. The COVID-19 pandemic initially reduced access to kidney transplantation among pediatric patients in the United States, but has not had a sustained effect.}

BACKGROUND:Kidney disease and dialysis significantly impact cognitive function across the age spectrum. Cognitive training (CT) and/or exercise training (ET) are promising approaches to preserve cognitive function among community-dwelling older adults, but have not been tested for cognition preservation in hemodialysis patients of all ages. In this manuscript, we summarize the protocol for the Interventions Made to Preserve Cognitive Function Trial (IMPCT). METHODS:We will perform a 2 × 2 factorial randomized controlled trial (RCT) of eligible adult (≥18 years) hemodialysis initiates (n = 200) to test whether intradialytic CT (brain games on a tablet PC), ET (foot peddlers) and combined CT + ET while undergoing hemodialysis preserves executive function compared to standard of care (SC). Participants will engage in the interventions to which they are randomized for 6 months. The primary objective is to compare, among interventions, the 3-month change in executive function measured using the Trail Making Test A (TMTA) and B (TMTB); specifically, executive function is calculated as TMTB-TMTA to account for psychomotor speed. This primary outcome was selected based on findings from our pilot study. The secondary objectives are to compare the risk of secondary cognitive outcomes, ESKD-specific clinical outcomes, and patient-centered outcomes at 3-months and 6-months. All data collection and interventions are conducted in the dialysis center. DISCUSSION:We hypothesize that receiving intradialytic CT or ET will better preserve executive function than SC but receiving combined CT + ET, will be the most effective intervention. The current trial will be an important step in understanding how intradialytic interventions might preserve cognitive health. TRIAL REGISTRATION:Clinicaltrials.Gov (Date: 8/6/18): # NCT03616535 . Protocol Version: 10 (April 2020). FUNDING:NIDDK R01DK114074.

BACKGROUND:HIV-infected (HIV+) donor to HIV+ recipient (HIV D+/R+) transplantation might improve access to transplantation for people living with HIV. However, it remains unknown whether transplant candidates living with HIV will accept the currently unknown risks of HIV D+/R+ transplantation. METHODS:We surveyed transplant candidates living with HIV from 9 US transplant centers regarding willingness to accept HIV+ donor organs. RESULTS:Among 116 participants, the median age was 55 years, 68% were men, and 78% were African American. Most were willing to accept HIV+ living donor organs (87%), HIV+ deceased donor organs (84%), and increased infectious risk donor organs (70%). Some (30%) were concerned about HIV superinfection; even among these respondents, 71% were willing to accept an HIV D+ organ. Respondents from centers that had already performed a transplant under an HIV D+/R+ transplantation research protocol were more willing to accept HIV+ deceased donor organs (89% vs. 71%, P = 0.04). Respondents who chose not to enroll in an HIV D+/R+ transplantation research protocol were less likely to believe that HIV D+/R+ transplantation was safe (45% vs. 77%, P = 0.02), and that HIV D+ organs would work similar to HIV D- organs (55% vs. 77%, P = 0.04), but more likely to believe they would receive an infection other than HIV from an HIV D+ organ (64% vs. 13%, P < 0.01). CONCLUSIONS:Willingness to accept HIV D+ organs among transplant candidates living with HIV does not seem to be a major barrier to HIV D+/R+ transplantation and may increase with growing HIV D+/R+ transplantation experience.

The outcomes of benzodiazepine and opioid co-prescription are not well-defined in transplant populations. We examined linked national transplant registry and pharmaceutical records to characterize benzodiazepine and opioid use in the years before and after transplant in large US cohort of kidney transplant recipients (2007-2016; N = 98 620), and associations (adjusted hazard ratio, _LCL aHR_UCL ) with death and graft failure. Among the cohort, 15.6% filled benzodiazepine prescriptions in the year before transplant, and 14.0% filled benzodiazepine prescriptions in the year after transplant (short-acting, 9.5%; long-acting, 3.3%; both 1.1%). Use of short-acting benzodiazepines in the year before transplant was associated with a 22% increased risk of death in the year after transplant (aHR, _1.08 1.22_1.38 ), while use of all classes in the year after transplant was associated with increased risk of death from >1 to 5 years (aHR: short-acting _1.29 1.39_1.48 ; long-acting _1.12 1.25_1.40 ; both _1.46 1.74_2.07 ). Recipients who used benzodiazepines were also more likely to fill opioid prescriptions. Recipients who filled both classes of benzodiazepine and the highest level of opioids had a 2.9-fold increased risk of death compared to recipients who did not use either. Co-prescription of benzodiazepines and opioids in kidney transplant recipients is associated with increased mortality. Ongoing research is needed to understand mechanisms of risk relationships.

Simple (Bosniak I) renal cysts are considered acceptable in living kidney donor selection in terms of cancer risk. However, they tend to increase in number and size over time and might compromise renal function in donors. To clarify their implications for long-term renal function, we characterized the prevalence of renal cysts in 454 individuals who donated at our center from 2000 to 2007. We estimated the association between the presence of cysts in the kidney remaining after nephrectomy (ie, retained cysts) and postdonation eGFR trajectory using mixed-effects linear regression. Donors with retained cysts (N = 86) were older (P < .001) and had slightly lower predonation eGFR (median 94 vs 98 mL/min/1.73 m² , P < .01) than those without cysts. Over a median 7.8 years, donors with retained cysts had lower baseline eGFR (_-8.7 -5.6 _-2.3  mL/min/1.73 m² , P < .01) but similar yearly change in eGFR (_-0.4 0.02 _0.4  mL/min/1.73 m² , P = .2) compared to those without retained cysts. Adjusting for predonation characteristics, there was no difference in baseline eGFR (P = .6) or yearly change in eGFR (P > .9). There continued to be no evidence of an association when we considered retained cyst(s) ≥10 mm or multiple retained cysts (all P > .05). These findings reaffirm current practices of accepting candidates with simple renal cysts for donor nephrectomy.

Background/UNASSIGNED:The Live Donor Champion (LDC) program trains kidney transplant (KT) candidates and their family/friends ("champions") as educator-advocates for live donor KT (LDKT). This program was created to empower patients and champions, particularly African American (AA) waitlist candidates that historically had lower access to LDKT. We assessed changes in knowledge about and comfort discussing live donation and donor referral associated with LDC participation, both overall and by participant race. Methods/UNASSIGNED:We compared 163 adult KT candidates who were LDC participants from October 2013 to May 2016 with 489 matched controls, both overall and by race. We compared changes in comfort and knowledge post-LDC using rank-sum tests among participants by race. We compared time to first live donor referral for participants versus controls, by race, using Cox regression. Results/UNASSIGNED: < 0.001); the impact of LDC participation was similar among non-AAs and AAs (p-interaction = 0.6). Conclusions/UNASSIGNED:The LDC program increased knowledge, comfort, and live donor referral for non-AA and AA participants, underscoring the effectiveness in the program in promoting LDKT in a population with historically lower access to LDKT.

BACKGROUND:One of the primary risks of HIV-positive to HIV-positive organ transplantation is loss of virological control because of donor-derived HIV superinfection, which occurs when an HIV-positive individual becomes infected with a new distinct HIV strain. In this study, as part of the larger HIV Organ Policy Equity pilot study, HIV-positive to HIV-positive kidney and liver transplant recipients in the USA were examined for evidence of sustained donor-derived HIV superinfection. METHODS:In this multicentre, prospective, observational study, HIV-positive to HIV-positive kidney and liver transplant recipients were followed in three hospitals in the USA. Candidates with well controlled HIV infection on ART, no active opportunistic infections, and minimum CD4 T-cell counts (>100 cells per μL for liver and >200 cells per μL for kidney per federal guidelines) were eligible to receive a kidney or liver from deceased HIV-positive donors without active infections or neoplasm. Peripheral blood mononuclear cells were collected from donor-recipient pairs at the time of transplantation, and from recipients at several timepoints up to 3 years after transplantation. Donor samples were assessed for HIV RNA viral load, CD4 cell count, and antiretroviral drug-resistant mutations. Donor and recipient HIV proviral DNA, and viral RNA from the viraemic timepoint were sequenced using a site-directed next-generation sequencing assay for the reverse transcriptase and gp41 genes. Neighbour-joining phylogenetic trees and direct sequence comparison were used to detect the presence of HIV superinfection. This study is registered with ClinicalTrials.gov, NCT02602262. FINDINGS:14 HIV-positive to HIV-positive kidney and eight liver transplant recipients were followed from March, 2016, to July, 2019. 17 recipients had adequate viral sequences allowing for HIV superinfection assessment. Eight donors were suppressed (viral load <400 copies per mL), and none had multiclass drug-resistant mutations detected. None of the recipients examined had evidence of HIV superinfection. One recipient had a viraemic episode (viral load of 2 080 000 copies per mL) 3 years after transplantation as a result of non-adherence to ART. Only recipient viral sequences were detected during the viraemic episode, suggesting that the donor virus, if present, was not reactivated despite temporary withdrawal of ART. INTERPRETATION:These findings suggest that loss of HIV suppression due to donor-derived HIV superinfection might not be a significant clinical concern in carefully monitored ART suppressed HIV-positive organ recipients. FUNDING:US National Institute of Allergy and Infectious Diseases and National Cancer Institute.