A 2020 Banff Antibody-mediatedInjury Working Group examination of international practices for diagnosing antibody-mediated rejection in kidney transplantation - a cohort study

The Banff antibody-mediated rejection (ABMR) classification is vulnerable to misinterpretation, but the reasons are unclear. To better understand this vulnerability, we evaluated how ABMR is diagnosed in practice. To do this, the Banff Antibody-Mediated Injury Workgroup electronically surveyed an international cohort of nephrologists/surgeons (n = 133) and renal pathologists (n = 99). Most providers (97%) responded that they use the Banff ABMR classification at least sometimes, but DSA information is often not readily available. Only 41.1% (55/133) of nephrologists/surgeons and 19.2% (19/99) of pathologists reported that they always have DSA results when the biopsy is available. Additionally, only 19.6% (26/133) of nephrologists/surgeons responded that non-HLA antibody or molecular transcripts are obtained when ABMR histologic features are present but DSA is undetected. Several respondents agreed that histologic features concerning for ABMR in the absence of DSA and/or C4d are not well accounted for in the current classification [31.3% (31/99) pathologists and 37.6% (50/133) nephrologist/surgeons]. The Banff ABMR classification appears widely accepted, but efforts to improve the accessibility of DSA information for the multidisciplinary care team are needed. Further clarity is also needed in Banff ABMR nomenclature to account for the spectrum of ABMR and for histologic features suspicious for ABMR when DSA is absent.

Kidney transplantation outcomes for adult recipients of pediatric donor kidneys

Despite a paucity of data assessing transplantation of deceased-donor pediatric donor kidneys into adult recipients, utilization of pediatric organs is declining in the UK, likely due to concerns that such organs may have inferior outcomes. However, we hypothesized that these concerns may be unfounded. As such, the aim of the study was to compare kidney transplant outcomes between adult recipients of pediatric and adult deceased-donor organs. Data were collected from the UK Transplant Registry for all adult (18+ years) deceased-donor single-kidney transplant recipients between January 2000 and January 2016. Univariable and multivariable analyses were undertaken, to compare a range of outcomes between recipients of kidneys from pediatric and adult donors. Transplants were stratified by the donor age (years) as follows: 0-16 (n = 666), 17-18 (n = 465), and 19-44 (n = 7378). Recipients of pediatric donor kidneys were observed to have improved long-term graft function, with a median creatinine at 1 year of 109 vs. 117 μmol/L for recipients of donors aged 0-16 vs. 19-44 years (P < .001). However, on multivariable analysis, this was not found to correspond to a significant difference in patient (P = .914) or graft survival (P = .190) between the donor age groups. Subgroup analysis within the younger donors found no significant differences in recipient outcomes between donors aged 0-6, 7-12, and 13-16 years. In this population cohort study, we identified excellent outcomes among adult recipients of pediatric donor kidneys. Pediatric donors are a valuable source of organs for adult recipients in an era where organ demand is rising.

Changing patterns of clinical decision making: are falling numbers of antibody incompatible transplants related to the increasing success of the UK Living Kidney Sharing Scheme? A national cohort study

Antibody incompatibility is a barrier to living kidney transplantation; antibody incompatible transplantation (AIT) is an accepted treatment modality, albeit higher risk. This study aims to determine changes to clinical decision making and access to AIT in the UK. An electronic survey was sent to all UK renal transplant centres (n = 24), in 2014, and again in 2018. Questions focused on entry & duration in the UKLKSS for HLA and ABO-incompatible pairs, Can and provision of direct AIT transplantation within those centres. Between 2014 & 2018, the duration recommended for patients in the UKLKSS increased. In 2014, 34.8% of centres reported leaving HLA-i pairs in the UKLKSS indefinitely, or reviewing on a case by case basis, by 2018 this increased to 61%. Centres offering direct HLA-i transplantation reduced from 58% to 37%. For low titre (1:8) ABO-i recipients, 66% of centres recommended at least 9 months (3 matching runs) in the UKLKSS scheme in 2018, compared to 47% in 2014, 50% fewer units consider direct ABO-i transplantation for unsuccessful pairs with high ABO titres (>1:512). Over time, clinicians appear to be facilitating more conservative management of AIT patients, potentially limiting access to living donor transplantation.

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.

Association of age with risk of first and subsequent allograft failure and mortality among young kidney transplant recipients in the USA - a retrospective cohort study

Adolescent age may be a high-risk period for kidney allograft failure. However, the knowledge on this topic is limited mostly to the first transplant. Among 20 960 patients aged ≤21 years at the first kidney transplantation from the US Renal Data System, we evaluated the association of age at the first kidney transplant with risk for the first and subsequent graft failures (1st, 2nd, and 3rd) using the conditional risk set model for recurrent time-to-event data. The median age was 15 (interquartile range: 9-18) years, and 18% received transplants twice or more during a median follow-up of 9.7 years. The risk for graft failures was highest in 16 to <18 years old with an adjusted hazard ratio (aHR) of 1.93 (95% CI, 1.73-2.15; reference: <3 years). When separately analyzed, the highest risk was observed in 17, 19, and 21 years old for the first, second, and third transplant, respectively. Those 16 to <18 years were also strongly associated with the highest risk for death after returning to dialysis (aHR, 4.01; 95% CI, 2.82-5.71). Adolescent recipients remain at high risk for allograft failure for a long time, which may result in high mortality risk, even though they surpass this high-risk period soon after the first transplant.

Relevance of KDPI value and acute rejection on kidney transplant outcomes in recipients with delayed graft function - a retrospective study

Delayed graft function (DGF) is associated with poorer graft survival and higher rate of acute rejection (AR). It is unknown whether this negative influence relies on the increased risk of AR or the DGF itself. The different Kidney Donor Profile Index (KDPI) values may also play a role in this interaction. Retrospective study aimed to evaluate the impact of DGF on graft function and graft survival in a subset of KT recipients (2004-2017). We also analyzed the relationship between KDPI and DGF. The study includes 601 KT, 226 of them (37%) developed DGF. Graft survival was lower in patients with DGF compared with non-DGF patients. Multivariable analysis revealed DGF as risk factor for graft loss, independently of the presence or not of acute rejection. Between DGF patients, we observed poorer graft survival in patients with higher KDPI value (>85%). We observed a trend of a greater impact of KDPI in patients with DGF, although this interaction was not statistically significant. Additionally, we observed poorer 12-month graft function in DGF patients. DGF is related to poorer graft survival independently of the developed acute rejection. This negative impact might be influenced by high KDPI values.

Should kidney allografts from old donors be allocated only to old recipients?

In several deceased donor kidney allocation systems, organs from elderly donors are allocated primarily to elderly recipients. The Eurotransplant Senior Program (ESP) was implemented in 1999, and since then, especially in Europe, the use of organs from elderly donors has steadily increased. The proportion of ≥60-year-old donors reported to the Collaborative Transplant Study (CTS) by European centers has doubled, from 21% in 2000-2001 to 42% in 2016-2017. Therefore, in the era of organ shortage it is a matter of debate whether kidney organs from elderly donors should only be allocated to elderly recipients or whether <65-year-old recipients can also benefit from these generally as "marginal" categorized organs. To discuss this issue, a European Consensus Meeting was organized by the CTS on April 12, 2018, in Heidelberg, in which 36 experts participated. Based on available evidence, it was unanimously concluded that kidney organs from 65- to 74-year-old donors can also be allocated to 55- to 64-year-old recipients, especially if these organs are from donors with no history of hypertension, no increased creatinine, no cerebrovascular death, and no other reasons for defining a marginal donor, such as diabetes or cancer.

Outcomes of induction antibody therapies in the nonbroadly sensitized adult deceased donor kidney transplant recipients: a retrospective cohort registry analysis

The outcomes of lymphocyte-depleting antibody induction therapy (LDAIT), [thymoglobulin (ATG) or alemtuzumab (ALM)] versus interleukin-2 receptor antagonist (IL-2RA) in the nonbroadly-sensitized [pretransplant calculated panel reactive antibody (cPRA), <80%] adult deceased donor kidney transplant recipients (adult-DDKTRs) are understudied. In this registry, study of 55 593 adult-DD-KTRs, outcomes of LDAIT [(ATG, N = 32 985) and (ALM, N = 9429)], and IL-2RA (N = 13 179) in <10% and 10-79% cPRA groups was analyzed. Adjusted odds ratio (aOR) of one-year biopsy-proven acute rejection (BPAR) was lower; while, aOR of 1-year composite of re-hospitalization, graft loss, or death was higher with LDAIT than IL2-RA in both cPRA groups. Adjusted odds ratio (aOR) of delayed graft function was higher with LDAIT than IL-2RA in the <10% cPRA group. Adjusted hazard ratio (aHR) of 5-year death-censored graft loss (DCGL) in both <80% cPRA groups seemed higher with ALM than other inductions [(<10% cPRA: ALM versus IL2RA, aHR = 1.11, 95% CI = 1.00-1.23 and ATG versus ALM: aHR = 0.84, 95% CI = 0.77-0.91; 10-79% cPRA: ALM versus IL2RA, aHR = 1.29, 95% CI = 1.02-1.64; and ATG versus ALM, aHR = 0.83, 95% CI = 0.70-0.98)]. Five-year aHR of death did not differ among induction therapies in both cPRA groups. In nonbroadly sensitized adult-DDKTRs, LDAIT is more protective against 1-year BPAR (not 5-year mortality) than IL-2RA; the trend of a higher 5-year DCGL risk with ALM than ATG or IL-2RA needs further investigation.

Kidney graft survival of >25 years: a single center report including associated graft biopsy results

Only few centers have reported their observations on patients with very long-term kidney graft survival of more than 25 years. Eighty-six subjects were identified in our center with graft survival of >25 years. Donor age was 31.3 ± 18.5 years. Mean duration of transplantation was 30.3 ± 3.6 years. At last follow-up, the cystatin C clearance was 47 ± 23 ml/min. Transplant biopsies for cause were performed in 30 subjects at a median of 28.4 years (19.1-40.3) after transplantation. Acute or chronic active T cell-mediated rejection was present in five cases and histological characteristics of acute or chronic active humoral rejection in eight cases. More than 80% of biopsies had inflammatory infiltrates in nonatrophic or atrophic cortical areas. The number of HLA mismatches were higher in biopsied subjects (3.0 ± 1.8 vs. 2.2 ± 1.7 without biopsy). Immunosuppressive therapy was adapted in most biopsied subjects; impaired graft function and proteinuria was unchanged at last follow-up. Sixty percent of all subjects had hyperparathyroidism (iPTH of the whole group: 132 ± 157 pg/ml), which was predominantly secondary, as judged by serum calcium and graft function. Young donor age was certainly a prerequisite of longterm graft survival. Nonetheless, inflammation or rejection in most biopsied patients suggests an important role of alloreactivity even in this late course.

Factors at de novo donor-specific antibody initial detection associated with allograft loss: a multicenter study

We aimed to evaluate patient factors including nonadherence and viral infection and de novo donor-specific antibody (dnDSA) characteristics [total immunoglobulin G (IgG), C1q, IgG3, and IgG4] as predictors of renal allograft failure in a multicenter cohort with dnDSA. We performed a retrospective observational study of 113 kidney transplant recipients with dnDSA and stored sera for analysis. Predictors of death-censored allograft loss were assessed by Cox proportional modeling. Death-censored allograft survival was 77.0% (87/113) during a median follow-up of 2.2 (IQR 1.2-3.7) years after dnDSA detection. Predictors of allograft failure included medication nonadherence [HR 6.5 (95% CI 2.6-15.9)], prior viral infection requiring immunosuppression reduction [HR 5.3 (95% CI 2.1-13.5)], IgG3 positivity [HR 3.8 (95% CI 1.5, 9.3)], and time post-transplant (years) until donor-specific antibody (DSA) detection [HR 1.2 (95% CI 1.0, 1.3)]. In the 67 patients who were biopsied at dnDSA detection, chronic antibody-mediated rejection [HR 11.4 (95% CI 2.3, 56.0)] and mixed rejection [HR 7.4 (95% CI 2.2, 24.8)] were associated with allograft failure. We conclude that patient factors, including a history of viral infection requiring immunosuppression reduction or medication nonadherence, combined with DSA and histologic parameters must be considered to understand the risk of allograft failure in patients with dnDSA.

Microvascular inflammation in renal allograft biopsies assessed by endothelial and leukocyte co-immunostain: a retrospective study on reproducibility and clinical/prognostic correlates

The most prominent histologic lesion in antibody-mediated rejection is microvascular inflammation (MVI); however, its recognition and scoring can be challenging and poorly reproducible between pathologists. We developed a dual immunohistochemical (IHC)-stain (anti-CD34/anti-CD45 for endothelium/leukocytes) as ancillary tool to improve on the semi-quantitative Banff scores and allow quantification of MVI. We examined the relationship between CD34-CD45 IHC-based quantitative MVI score (the inflamed peritubular capillary ratio, iptcr) and renal-graft failure or donor-specific antibodies (DSA) strength at the time of biopsy. Quantitative iptcr score was significantly associated with renal graft failure (hazard ratio 1.81, per 1 SD-unit [0.13 points] of iptcr-increase; P = 0.026) and predicted the presence and strength of DSA (ordinal odds ratio: 2.42; P = 0.005; 75 biopsies/60 kidney transplant recipients; 30 HLA- and/or ABO-incompatible). Next, we assessed inter-pathologist agreement for ptc score and ptc extent (focal/diffuse) using CD34-CD45 IHC as compared to conventional stain. Compared to conventional stain, CD34-CD45 IHC significantly increased inter-pathologist agreement on ptc score severity and extent (κ-coefficient from 0.52-0.80 and 0.46-0.68, respectively, P < 0.001). Our findings show that CD34-CD45 IHC improves reproducibility of MVI scoring and facilitates MVI quantification and introduction of a dual anti-CD34/CD45 has the potential to improve recognition of MVI ahead of DSA results.

A method to reduce variability in scoring antibody-mediated rejection in renal allografts: implications for clinical trials - a retrospective study

Poor reproducibility in scoring antibody-mediated rejection (ABMR) using the Banff criteria might limit the use of histology in clinical trials. We evaluated the reproducibility of Banff scoring of 67 biopsies by six renal pathologists at three institutions. Agreement by any two pathologists was poor: 44.8-65.7% for glomerulitis, 44.8-67.2% for peritubular capillaritis, and 53.7-80.6% for chronic glomerulopathy (cg). All pathologists agreed on cg0 (n = 20) and cg3 (n = 9) cases, however, many disagreed on scores of cg1 or cg2. The range for the incidence of composite diagnoses by individual pathologists was: 16.4-22.4% for no ABMR; 17.9-47.8% for active ABMR; and 35.8-59.7% for chronic, active antibody-mediated rejection (cABMR). A "majority rules" approach was then tested in which the scores of three pathologists were used to reach an agreement. This increased consensus both for individual scores (ex. 67.2-77.6% for cg) and for composite diagnoses (ex. 74.6-86.6% cABMR). Modeling using these results showed that differences in individual scoring could affect the outcome assessment in a mock study of cABMR. We conclude that the Banff schema has high variability and a majority rules approach could be used to adjudicate differences between pathologists and reduce variability in scoring in clinical trials.

Chronic-active antibody-mediated rejection with or without donor-specific antibodies has similar histomorphology and clinical outcome - a retrospective study

Chronic-active antibody-mediated rejection (c-aABMR) is defined as histological evidence of chronic endothelial injury (cg), also known as transplant glomerulopathy, and either microvascular inflammation (MVI) or positivity for C4d. Importantly, the presence of donor-specific antibodies (DSA) is currently still mandatory for the diagnosis of c-aABMR. This retrospective study of 41 c-aABMR patients investigates whether cases suspicious for c-aABMR (DSA negative, n = 24) differ from cases of c-aABMR (DSA positive, n = 17) with respect to renal histology, allograft function and long-term graft survival. All included patients had progressive loss of allograft function and were diagnosed by for cause biopsy and scored according to the Banff '15 criteria. In all DSApos cases, DSA were de novo and the majority was directed against HLA-II being mostly anti-HLA-DQ antibodies. There were no statistically significant differences in clinical characteristics, decline in allograft function and renal allograft survival in cases with or without DSAs. All cases showed chronic histomorphological damage and inflammation, irrespective of the presence of DSA. Renal histology and clinical outcome of patients suspicious for c-aABMR (DSAneg) do not significantly differ from patients with a diagnosis of c-aABMR (DSApos). We believe that our study adds to the ongoing debate regarding the need for DSAs to be present for the diagnosis of c-aABMR.

Renal volume assessed by magnetic resonance imaging volumetry correlates with renal function in living kidney donors pre- and postdonation: a retrospective cohort study

Renal function of potential living kidney donors is routinely assessed with scintigraphy. Kidney anatomy is evaluated by imaging techniques such as magnetic resonance imaging (MRI). We evaluated if a MRI-based renal volumetry is a good predictor of kidney function pre- and postdonation. We retrospectively analyzed the renal volume (RV) in a MRI of 100 living kidney donors. RV was correlated with the tubular excretion rate (TER) of MAG3-scintigraphy, a measured creatinine clearance (CrCl), and the estimated glomerular filtration rate (eGFR) by Cockcroft-Gault (CG), CKD-EPI, and modification of diet in renal disease (MDRD) formula pre- and postdonation during a follow-up of 3 years. RV correlated significantly with the TER (total: r = 0.6735, P < 0.0001). Correlation between RV and renal function was the highest for eGFR by CG (r = 0.5595, P < 0.0001), in comparison with CrCl, MDRD-GFR, and CKD-EPI-GFR predonation. RV significantly correlated with CG-GFR postdonation and predicted CG-GFR until 3 years after donation. MRI renal volumetry might be an alternative technique for the evaluation of split renal function and prediction of renal function postdonation in living kidney donors.

Regression of left atrial diameter after kidney transplantation is associated with prolonged survival: an observational study

Renal transplantation reduces the dramatically elevated risk of cardiovascular death in dialysis patients. We previously showed that left atrial diameter before transplantation predicts cardiovascular and overall mortality. Now, we investigated the association of changes in cardiac morphology after transplantation and mortality. We retrospectively analyzed data from the Austrian transplant repository using multivariable Cox and competing risk models and multivariable logistic regression for the prediction of changes in cardiac morphology. We identified 414 patients with a median follow-up of 8 years and observed a significant progression of mean diameter of left atrium (LA), right atrium and right ventricle and a significant regression of left ventricle. Complete case analysis of 243 patients with a regression of initially enlarged LA diameter had a significantly lower risk of adjusted overall and cardiovascular mortality; hazard ratio (HR 0.45, 95% CI 0.30-0.69, P < 0.001, 124 deaths), and HR of 0.43 [95% CI 0.21-0.92, P = 0.029, 48 cardiovascular (CV) deaths], respectively. Only age at transplantation was significantly associated with regression of LA (OR 0.75, 95% CI 0.60-0.93, P = 0.007). Patients with regression of LA after kidney transplantation exhibited a lower overall and CV mortality risk. Besides age, peritoneal dialysis and antihypertensive therapy were mediators of LA regression.

Tacrolimus and mycophenolate regimen and subclinical tubulo-interstitial inflammation in low immunological risk renal transplants

The aim was to evaluate the relationship between maintenance immunosuppression, subclinical tubulo-interstitial inflammation and interstitial fibrosis/tubular atrophy (IF/TA) in surveillance biopsies performed in low immunological risk renal transplants at two transplant centers. The Barcelona cohort consisted of 109 early and 66 late biopsies in patients receiving high tacrolimus (TAC-C₀ target at 1-year 6-10 ng/ml) and reduced MMF dose (500 mg bid at 1-year). The Oslo cohort consisted of 262 early and 237 late biopsies performed in patients treated with low TAC-C₀ (target 3-7 ng/ml) and standard MMF dose (750 mg bid). Subclinical inflammation, adjusted for confounders, was associated with low TAC-C₀ in the early (OR: 0.75, 95% CI: 0.61-0.92; P = 0.006) and late biopsies (OR: 0.69, 95% CI: 0.50-0.95; P = 0.023) from Barcelona. In the Oslo cohort, it was associated with low MMF in early biopsies (OR: 0.90, 95% CI: 0.83-0.98; P = 0.0101) and with low TAC-C₀ in late biopsies (OR: 0.77, 95% CI: 0.61-0.97; P = 0.0286). MMF dose was significantly reduced in Oslo between early and late biopsies. IF/TA was not associated with TAC-C₀ or MMF dose in the multivariate analysis. Our data suggest that in TAC- and MMF-based regimens, TAC-C₀ levels are associated with subclinical inflammation in patients receiving reduced MMF dose.

The detrimental impact of persistent vs an isolated occurrence of de novo donor-specific antibodies on intermediate-term renal transplant outcomes

BACKGROUND

De novo donor-specific antibodies (dnDSA) after renal transplant are associated with acute rejection (AR) and graft loss, yet most recipients with dnDSA have stable function and no AR. We assessed whether the persistence of dnDSA increased the risk of a detrimental outcome.

METHODS

A single-center review of renal transplant recipients monitored for dnDSA at multiple time points post-transplant. An Isolated dnDSA was defined as one positive dnDSA and no additional positive tests, whereas ≥2 positive dnDSA was defined as persistent dnDSA.

RESULTS

Of 708 recipients, 22% developed dnDSA, of whom 64% had persistent dnDSA. At median follow-up of 35 (range 12-74) months, there were fewer episodes of AR in the isolated dnDSA vs the persistent dnDSA group (2% vs 22%; P<.001,) and fewer graft losses with isolated dnDSA vs persistent dnDSA (0% vs 10%; P=.03). Within the persistent dnDSA group, recipients with dnDSA ≥60% of time points, had more AR (32% vs 16%, P=.10) and more graft losses (21% vs 2%; P=.003) than those with dnDSA<60%.

CONCLUSIONS

Persistence of dnDSA resulted in more AR and graft failure than a single positive value. Recipients with longer duration of dnDSA persistence had an additional increased risk of AR and graft failure.

An analysis of the survival outcomes of simultaneous pancreas and kidney transplantation compared to live donor kidney transplantation in patients with type 1 diabetes: a UK Transplant Registry study

Transplant options for patients with type 1 diabetes and end-stage renal disease (ESRD) include deceased donor kidney, live donor kidney (LDK) and simultaneous pancreas-kidney (SPK) transplantation. The aim of this study was to compare outcomes between LDK and SPK for patients with type 1 diabetes and ESRD in the UK. Data on all SPK (n = 1739) and LDK (n = 385) transplants performed between January 2001 and December 2014 were obtained from the UK Transplant Registry. Unadjusted patient and kidney graft survival were calculated using the Kaplan-Meier method. Multivariate analysis of kidney graft and patient survival was performed using Cox proportional hazards regression. There was no significant difference in patient (P = 0.435) or kidney graft survival (P = 0.204) on univariate analysis. On multivariate analysis there was no association between LDK/SPK and patient survival [HR 0.71 (0.47-1.06), P = 0.095]. However, LDK was associated with an overall lower risk for kidney graft failure [HR 0.60 (0.38-0.94), P = 0.025]. SPK recipients with a functioning pancreas graft had significantly better kidney graft and patient survival than LDK recipients or those with a failed pancreas graft. SPK transplantation does not confer an overall survival advantage compared to LDK. However, those SPK recipients with a functioning pancreas have significantly better outcomes.

Ureteral stent placement and immediate graft function are associated with increased risk of BK viremia in the first year after kidney transplantation

Ureteral stent (UrSt) placement has been shown to be a significant independent risk factor for BK viruria, viremia, and BK virus nephropathy. We assessed whether this observation could be validated at our high volume kidney transplant center that has had a strong historical focus on BK virus nephropathy detection. We performed a retrospective case-control study of adults receiving a kidney-only transplant and followed for 1 year between 2004 and 2011 with uniform immunosuppression and use of blood BK virus PCR screening protocol. Among 1147 patients, 443 (38.6%) received a UrSt and 17.2% with a UrSt had BK viremia versus 13.5% without stent (odds ratio 1.33; 95% CI: 1.00-1.78). We confirmed a previously reported association between immediate graft function (IGF) and higher rate of BK viremia (15.7% vs. 5.9% in patients without IGF). On multivariable competing risks Cox regression in patients with IGF, UrSt (adjusted hazard ratio [aHR] 1.35; 95% CI: 1.04-1.75) and African American race (aHR 1.47; 95% CI: 1.04-2.09) significantly increased the risk for BK viremia. In the largest sample size to date, we confirmed that UrSt placement during kidney transplant surgery is a risk factor for BK viremia within the first year post-transplant and that IGF is associated with BK viremia.

Increasing access to renal transplantation in India through our single-center kidney paired donation program: a model for the developing world to prevent commercial transplantation

Because access to transplantation with HLA-desensitization protocols and ABO incompatible transplantation is very limited due to high costs and increased risk of infections from more intense immunosuppression, kidney paired donation (KPD) promises hope to a growing number of end-stage renal disease (ESRD) patient in India. We present a government and institutional ethical review board approved study of 56 ESRD patients [25 two-way and 2 three-way pairs] who consented to participate in KPD transplantation at our center in 2013, performed to avoid blood group incompatibility (n = 52) or positive cross-match (n = 4). All patients had anatomic, functional, and immunologically comparable donors. The waiting time in KPD was short as compared to deceased donor transplantation. Laparoscopic donor nephrectomy was performed in 54 donors. Donor relationships were spousal (n = 40), parental (n = 13), others (n = 3), with median HLA match of 1. Graft survival was 97.5%. Three patients died with functioning graft. 16% had biopsy-proven acute rejection. Mean serum creatinine was 1.2 mg/dl at 0.73 ± 0.32 months follow-up. KPD is a viable, legal, and rapidly growing modality for facilitating LDRT for patients who are incompatible with their healthy, willing living donor. To our knowledge, this is the largest single-center report from India.