Faculty Bibliography

BACKGROUND AND OBJECTIVES:Patients with sickle cell disease-associated kidney failure have high mortality, which might be lowered by kidney transplantation. However, because they show higher post-transplant mortality compared with patients with other kidney failure etiologies, kidney transplantation remains controversial in this population, potentially limiting their chance of receiving transplantation. We aimed to quantify the decrease in mortality associated with transplantation in this population and determine the chance of receiving transplantation with sickle cell disease as the cause of kidney failure as compared with other etiologies of kidney failure. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS:Using a national registry, we studied all adults with kidney failure who began maintenance dialysis or were added to the kidney transplant waiting list in 1998-2017. To quantify the decrease in mortality associated with transplantation, we measured the absolute risk difference and hazard ratio for mortality in matched pairs of transplant recipients versus waitlisted candidates in the sickle cell and control groups. To compare the chance of receiving transplantation, we estimated hazard ratios for receiving transplantation in the sickle cell and control groups, treating death as a competing risk. RESULTS:=0.8). Nonetheless, the sickle cell group was less likely to receive transplantation than the controls (subdistribution hazard ratio, 0.73; 95% confidence interval, 0.61 to 0.87). Similar disparities were found among waitlisted candidates (subdistribution hazard ratio, 0.62; 95% confidence interval, 0.53 to 0.72). CONCLUSIONS:Patients with sickle cell disease-associated kidney failure exhibited similar decreases in mortality associated with kidney transplantation as compared with those with other kidney failure etiologies. Nonetheless, the sickle cell population was less likely to receive transplantation, even after waitlist registration.

Incompatible living donor kidney transplant recipients (ILDKTr) have pre-existing donor-specific antibody (DSA) that, despite desensitization, may persist or reappear with resulting consequences, including delayed graft function (DGF) and acute rejection (AR). To quantify the risk of DGF and AR in ILDKT and downstream effects, we compared 1406 ILDKTr to 17 542 compatible LDKT recipients (CLDKTr) using a 25-center cohort with novel SRTR linkage. We characterized DSA strength as positive Luminex, negative flow crossmatch (PLNF); positive flow, negative cytotoxic crossmatch (PFNC); or positive cytotoxic crossmatch (PCC). DGF occurred in 3.1% of CLDKT, 3.5% of PLNF, 5.7% of PFNC, and 7.6% of PCC recipients, which translated to higher DGF for PCC recipients (aOR = _1.03 1.68_2.72 ). However, the impact of DGF on mortality and DCGF risk was no higher for ILDKT than CLDKT (p interaction > .1). AR developed in 8.4% of CLDKT, 18.2% of PLNF, 21.3% of PFNC, and 21.7% of PCC recipients, which translated to higher AR (aOR PLNF = _1.45 2.09_3.02 ; PFNC = _1.67 2.40_3.46 ; PCC = _1.48 2.24_3.37 ). Although the impact of AR on mortality was no higher for ILDKT than CLDKT (p interaction = .1), its impact on DCGF risk was less consequential for ILDKT (aHR = _1.34 1.62_1.95 ) than CLDKT (aHR = _1.96 2.29_2.67 ) (p interaction = .004). Providers should consider these risks during preoperative counseling, and strategies to mitigate them should be considered.

BACKGROUND:Transplant recipients with HIV may have worse outcomes with coronavirus disease 2019 (COVID-19) due to impaired T-cell function coupled with immunosuppressive drugs. Alternatively, immunosuppression might reduce inflammatory complications and/or antiretrovirals could be protective. METHODS:Prospective reporting of all cases of SARS-CoV-2 infection was required within the HOPE in Action Multicenter Consortium, a cohort of kidney and liver transplant recipients with HIV who have received organs from donors with and without HIV at 32 transplant centers in the United States. RESULTS:Between March 20, 2020 and September 25, 2020, there were 11 COVID-19 cases among 291 kidney and liver recipients with HIV (4%). In those with COVID-19, median age was 59 y, 10 were male, 8 were kidney recipients, and 5 had donors with HIV. A higher proportion of recipients with COVID-19 compared with the overall HOPE in the Action cohort were Hispanic (55% versus 12%) and received transplants in New York City (73% versus 34%, P < 0.05). Most (10/11, 91%) were hospitalized. High-level oxygen support was required in 7 and intensive care in 5; 1 participant opted for palliative care instead of transfer to the intensive care unit. HIV RNA was undetectable in all. Median absolute lymphocyte count was 0.3 × 103 cells/μL. Median CD4 pre-COVID-19 was 298 cells/μL, declining to <200 cells/μl in 6/7 with measurements on admission. Treatment included high-dose steroids (n = 6), tocilizumab (n = 3), remdesivir (n = 2), and convalescent plasma (n = 2). Four patients (36%) died. CONCLUSIONS:Within a national prospective cohort of kidney and liver transplant recipients with HIV, we report high mortality from COVID-19.

Desensitization has enabled incompatible living donor kidney transplantation (ILDKT) across HLA/ABO barriers, but added immunomodulation might put patients at increased risk of infections. We studied 475 recipients from our center from 2010 to 2015, categorized by desensitization intensity: none/compatible (n = 260), low (0-4 plasmaphereses, n = 47), moderate (5-9, n = 74), and high (≥10, n = 94). The 1-year cumulative incidence of infection was 50.1%, 49.8%, 66.0%, and 73.5% for recipients who received none, low, moderate, and high-intensity desensitization (P < .001). The most common infections were UTI (33.5% of ILDKT vs. 21.5% compatible), opportunistic (21.9% vs. 10.8%), and bloodstream (19.1% vs. 5.4%) (P < .001). In weighted models, a trend toward increased risk was seen in low (wIRR = _0.77 1.40_2.56 ,P = .3) and moderately (wIRR = _0.88 1.35_2.06 ,P = .2) desensitized recipients, with a statistically significant 2.22-fold (wIRR = _1.33 2.22_3.72 ,P = .002) increased risk in highly desensitized recipients. Recipients with ≥4 infections were at higher risk of prolonged hospitalization (wIRR = _2.62 3.57_4.88 , P < .001) and death-censored graft loss (wHR = _1.15 4.01_13.95 ,P = .03). Post-KT infections are more common in desensitized ILDKT recipients. A subset of highly desensitized patients is at ultra-high risk for infections. Strategies should be designed to protect patients from the morbidity of recurrent infections, and to extend the survival benefit of ILDKT across the spectrum of recipients.

HIV-positive donor to HIV-positive recipient (HIV D+/R+) transplantation is permitted in the United States under the HIV Organ Policy Equity Act. To explore safety and the risk attributable to an HIV+ donor, we performed a prospective multicenter pilot study comparing HIV D+/R+ vs HIV-negative donor to HIV+ recipient (HIV D-/R+) kidney transplantation (KT). From 3/2016 to 7/2019 at 14 centers, there were 75 HIV+ KTs: 25 D+ and 50 D- (22 recipients from D- with false positive HIV tests). Median follow-up was 1.7 years. There were no deaths nor differences in 1-year graft survival (91% D+ vs 92% D-, P = .9), 1-year mean estimated glomerular filtration rate (63 mL/min D+ vs 57 mL/min D-, P = .31), HIV breakthrough (4% D+ vs 6% D-, P > .99), infectious hospitalizations (28% vs 26%, P = .85), or opportunistic infections (16% vs 12%, P = .72). One-year rejection was higher for D+ recipients (50% vs 29%, HR: 1.83, 95% CI 0.84-3.95, P = .13) but did not reach statistical significance; rejection was lower with lymphocyte-depleting induction (21% vs 44%, HR: 0.33, 95% CI 0.21-0.87, P = .03). In this multicenter pilot study directly comparing HIV D+/R+ with HIV D-/R+ KT, overall transplant and HIV outcomes were excellent; a trend toward higher rejection with D+ raises concerns that merit further investigation.

BACKGROUND:Desensitization protocols for HLA-incompatible living donor kidney transplantation (ILDKT) vary across centers. The impact of these, as well as other practice variations, on ILDKT outcomes remain unknown. METHODS:We sought to quantify center-level variation in mortality and graft loss following ILDKT using a 25-center cohort of 1358 ILDKT recipients with linkage to SRTR for accurate outcome ascertainment. We used multilevel Cox regression with shared frailty to determine the variation in post-ILDKT outcomes attributable to between-center differences, and to identify any center-level characteristics associated with improved post-ILDKT outcomes. RESULTS:After adjusting for patient-level characteristics, only 6 centers (24%) had lower mortality and 1 (4%) had higher mortality than average. Similarly, only 5 centers (20%) had higher graft loss and 2 had lower graft loss than average. Only 4.7% of the differences in mortality (p<0.01) and 4.4% of the differences in graft loss (p<0.01) were attributable to between-center variation. These translated to a median hazard ratio of 1.36 for mortality and 1.34 of graft loss for similar candidates at different centers. Post-ILDKT outcomes were not associated with the following center-level characteristics: ILDKT volume and transplanting a higher proportion of highly sensitized, prior transplant, preemptive, or minority candidates. CONCLUSION/CONCLUSIONS:Unlike most aspects of transplantation where center-level variation and volume impact outcomes, we did not find substantial evidence for this in ILDKT. Our findings support the continued practice of ILDKT across these diverse centers.