Temporal trends in kidney paired donation in the United States: 2006-2021 UNOS/OPTN database analysis.

Kidney paired donation (KPD) is a major innovation that is changing the landscape of kidney transplantation in the United States. We used the 2006-2021 United Network for Organ Sharing data to examine trends over time. KPD is increasing, with 1 in 5 living donor kidney transplants (LDKTs) in 2021 facilitated by KPD. The proportion of LDKT performed via KPD was comparable for non-Whites and Whites. An increasing proportion of KPD transplants are going to non-Whites. End-chain recipients are not identified in the database. To what extent these trends reflect how end-chain kidneys are allocated, as opposed to increase in living donation among minorities, remains unclear. Half the LDKT in 2021 in sensitized (panel reactive antibody ≥ 80%) and highly sensitized (panel reactive antibody ≥ 98%) groups occurred via KPD. Yet, the proportion of KPD transplants performed in sensitized recipients has declined since 2013, likely due to changes in the deceased donor allocation policies and newer KPD strategies such as compatible KPD. In 2021, 40% of the programs reported not performing any KPD transplants. Our study highlights the need for understanding barriers to pursuing and expanding KPD at the center level and the need for more detailed and accurate data collection at the national level.

Potassium-lowering effects of sodium zirconium cyclosilicate in the early post-transplant period.

PROBLEM: Hyperkalemia is a serious condition among intra-abdominal transplant recipients, and the safety and efficacy of sodium zirconium cyclosilicate (SZC) for its management during the early post-transplant period are not well-established. METHODS: Adults who received at least one 10-g dose of SZC within 14 days after an intra-abdominal transplant between January 2020 and July 2022 were included in our study. The primary outcome was the change in potassium (K+) levels following the first SZC dose. Other analyses explored adjunctive potassium-lowering therapies, potential gastrointestinal complications, and patient subgroups based on therapy and transplant type. RESULTS: Among the recipients (n = 46), 11 were kidney recipients, 26 were liver recipients, seven were simultaneous liver/kidney recipients, and two were simultaneous pancreas/kidney recipients. The mean time to first dose post-transplant was 7.6 (±4) days, and the mean change in serum K+ after the initial SZC dose was -.27 mEq (p = .001). No gastrointestinal complications were observed following the SZC dose. The mean increase in serum bicarbonate was .58 mEq (p = .41) following the first dose of SZC. Four kidney recipients required dialysis following the SZC dose. CONCLUSION: This study represents the largest investigation on the use of SZC in transplant recipients. A single 10-g dose of SZC reduced serum K+ levels in all subgroups, while the use of adjunctive K+-lowering therapies did not provide additional reduction beyond the effects of SZC. Importantly, no gastrointestinal complications were observed. These findings suggest that SZC may be a safe and promising therapeutic option for hyperkalemia management following solid organ transplantation.

Genetic evaluation of living kidney donor candidates: A review and recommendations for best practices.

The growing accessibility and falling costs of genetic sequencing techniques has expanded the utilization of genetic testing in clinical practice. For living kidney donation, genetic evaluation has been increasingly used to identify genetic kidney disease in potential candidates, especially in those of younger ages. However, genetic testing on asymptomatic living kidney donors remains fraught with many challenges and uncertainties. Not all transplant practitioners are aware of the limitations of genetic testing, are comfortable with selecting testing methods, comprehending test results, or providing counsel, and many do not have access to a renal genetic counselor or a clinical geneticist. Although genetic testing can be a valuable tool in living kidney donor evaluation, its overall benefit in donor evaluation has not been demonstrated and it can also lead to confusion, inappropriate donor exclusion, or misleading reassurance. Until more published data become available, this practice resource should provide guidance for centers and transplant practitioners on the responsible use of genetic testing in the evaluation of living kidney donor candidates.

Pre-transplant hypoalbuminemia is not associated with worse short-term outcomes among kidney transplant recipients.

INTRODUCTION: Serum albumin is an indicator of overall health status, but it remains unclear how pre-transplant hypoalbuminemia is associated with early post-transplant outcomes. METHODS: This study included all adult kidney transplant recipients (KTRs) at our center from 01/01/2001-12/31/2017 with serum albumin measured within 30 days before transplantation. KTRs were grouped based on pretransplant albumin level normal (≥4.0 g/dL), mild (≥3.5 - < 4.0g/dL), moderate (≥3.0 - < 3.5g/dL), or severe hypoalbuminemia (<3.0g/dL). Outcomes of interest included: length of hospital stay (LOS), readmission within 30 days, delayed graft function(DGF), and re-operation related to post-transplant surgical complications. We also analyzed rejection, graft failure, and death within 6 months post-transplant. RESULTS: A total of 2807 KTRs were included 43.6% had normal serum albumin, 35.3% mild, 16.6% moderate, and 4.5% severe hypoalbuminemia. Mild and moderate hypoalbuminemia were associated with a shorter LOS by 1.22 (p < 0.001) and 0.80 days (p = 0.01), respectively, compared to normal albumin. Moderate (HR: 0.58; 95% CI: 0.37-0.91; p = 0.02) and severe hypoalbuminemia (HR: 0.21; 95% CI: 0.07-0.68; p = 0.01) were associated with significantly lower rates of acute rejection within 6 months post-transplant. CONCLUSION: Patients with pre-transplant hypoalbuminemia have post-transplant outcomes similar to those with normal serum albumin, but with a lower risk of acute rejection based on the degree of hypoalbuminemia.

Seasonal variation of cytomegalovirus disease in kidney transplant recipients.

PURPOSE: Studies conducted in the northern United States found cytomegalovirus (CMV) disease after liver transplantation follows a seasonal pattern, with increased incidence in fall and winter. This has not been evaluated in kidney transplant recipients. Improved understanding of CMV seasonality may help guide use of preventative therapies. METHODS: We evaluated adult patients receiving a kidney transplant at our center in Wisconsin from January 1, 1995 to December 31, 2018. CMV event was defined as quantifiable viral replication with clinical signs or symptoms suspicious for CMV per current consensus recommendations. Seasons were divided as follows: winter (December-February), spring (March-May), summer (June-August), and fall (September-November). The primary objective was to evaluate the annual distribution of CMV disease and determine whether this differed by season. RESULTS: There were 6151 kidney transplants in the study period. A total of 913 patients had 1492 episodes of CMV. Median time from transplant to first detection was 5.51 months (interquartile range [IQR] 2.87-11.7). The observed overall incidence exceeded the expected incidence in winter (+.7%), spring (+5.5%), and fall (+3.4%) and was less than expected in summer (-9.5%) (p = .18). The incidence of CMV during summer, however, was 21% less than expected (p = .001) in recipients who were CMV positive (R+) at the time of transplantation. No such difference was observed in CMV negative recipients (R-; p = .58). CONCLUSION: CMV after kidney transplant appears to be less common during the summer season in patients who were R+ at transplant but does not follow seasonal variation in R-. Reasons for this are unclear but are likely related to CMV-specific cell-mediated immunity. These findings may have clinical implications, particularly the use of non-pharmacologic strategies to improve response to antiviral therapy.

Discordance in cytomegalovirus viremia in kidney recipients from the same donor is associated with the worst outcomes.

BACKGROUND: Cytomegalovirus (CMV) is a common viral infection in kidney transplant recipients (KTR) that has been associated with negative outcomes. The effect on outcomes of concordance versus discordance in CMV between two different recipients of kidneys from the same donor is largely unknown. METHODS: We reviewed all adult deceased donor kidney transplant recipients (DDKTs) for which both kidneys were transplanted to two different recipients at our center between 2014 and 2019. Recipient pairs from each donor were divided into groups based on concordance or discordance for the development of CMV viremia between the pair; concordant no CMV (cc-no-CMV) if neither KTR developed CMV, concordant CMV (cc-CMV) if both KTRs developed CMV. The discordant group was then further divided based on the individual development of CMV (dc-CMV) or lack of development of CMV (dc-no-CMV). Patient mortality and death-censored graft failure (DCGF) were outcomes of interest. RESULTS: Of 578 KTRs, 67% were cc-no-CMV, 5% were cc-CMV, 14% were dc-no-CMV, and 14% dc-CMV. Some of the baseline characteristics differ among the groups including a higher prevalence of high-risk serostatus (D+/R-) in cc-CMV (32%) and dc-CMV (32%). In multivariate analysis, with reference to cc-no-CMV, dc-CMV was associated with increased risk for DCGF (HR 3.13, 95% CI 1.58-6.19), and so was delayed graft function. Factors associated with increased risk of mortality were advanced recipient age and DGF. cc-CMV was neither associated with mortality nor DCGF. CONCLUSIONS: These findings support that in certain contexts, CMV viremia has adverse allograft outcomes, and this is highlighted when illustrated via discordance in CMV between pair kidneys from the same deceased donor.

Hypoalbuminemia is a risk factor for invasive fungal infections and poor outcomes in infected kidney transplant recipients.

INTRODUCTION: Invasive fungal infections (IFI), are estimated to occur in 2%-14% of kidney transplant recipients (KTRs) in the current era of immune suppression and are associated with high mortality rates. We hypothesized that hypoalbuminemia in KTRs is a risk factor for IFI and would be associated with poor outcomes. METHODS: In this study, using data from a prospective cohort registry, we describe the frequency of IFI due to Blastomycosis, Coccidioidomycosis, Histoplasmosis, Aspergillosis, and Cryptococcus in KTRs with serum albumin levels measured 3-6 months before diagnosis. Controls were selected based on incidence density sampling. KTRs were divided into three groups based on the pre-IFI serum albumin level: normal (≥4 g/dL), mild (3-4 g/dL), or severe (<3 g/dL) hypoalbuminemia. Outcomes of interest were uncensored graft failure after IFI and overall mortality. RESULTS: A total of 113 KTRs with IFI were compared with 348 controls. The incidence rate of IFI among individuals with normal, mild, and severe hypoalbuminemia was 3.6, 8.7, and 29.3 per 100 person-years, respectively. After adjustment for multiple variables, the trend for risk of uncensored graft failure following IFI was greater in KTRS with mild (HR = 2.1; 95% CI, .75-6.1) and severe (HR = 4.47; 95% CI, 1.56-12.8) hypoalbuminemia (P-trend < .001) compared to those with normal serum albumin. Similarly, mortality was higher in severe hypoalbuminemia (HR = 1.9; 95% CI, .67-5.6) compared to normal serum albumin (P-trend < .001). CONCLUSION: Hypoalbuminemia precedes the diagnosis of IFI in KTRs, and is associated with poor outcomes following IFI. Hypoalbuminemia may be a useful predictor of IFI in KTRs and could be incorporated into screening algorithms.

Post-transplant idiopathic immune complex membrano-proliferative glomerulonephritis: Characteristics and outcomes.

BACKGROUND: There is little published information on the natural history and the treatment of immune complex membrano-proliferative glomerulonephritis (IC-MPGN) of unknown cause in the transplanted kidney. MATERIALS AND METHODS: From 01/2004 to 12/2018, 41 patients had the diagnosis of post-transplant idiopathic IC-MPGN and were included in the study. RESULTS: The mean age of the cohort at the time of transplant was 50 ± 13 years. The most common presentation was increased proteinuria, followed by kidney dysfunction. Fewer than 50% of patients had hematuria at presentation. 25 patients (61%) had no change in their baseline immunosuppression after the diagnosis of idiopathic IC-MPGN. Eight patients (19.5%) received steroids alone, and 8 patients (19.5%) received rituximab with (7) or without (1) steroids. The patients who received rituximab had better uncensored graft survival than the patients who received no treatment (p = 0.02), but the benefit of steroids compared to no treatment did not reach statistical significance (p = 0.05). The multivariate analysis retained eGFR < 30 mL/min/1.73m2 at time of diagnosis (HR = 3.30, p = 0.02; 95% Cl 1.15 - 9.46) as a significant predictor of graft loss. In this analysis, treatment of idiopathic IC-MPGN was associated with lower graft loss (HR = 0.22, p = 0.02; 95% Cl 0.06 - 0.78). CONCLUSION: To the best of our knowledge, this is the largest clinic-pathological series of post-transplant idiopathic IC-MPGN. Treatment of idiopathic IC-MPGN may be associated with better graft outcomes.

Secondary oxalate nephropathy and kidney transplantation.

PURPOSE OF REVIEW: Secondary hyperoxaluria is associated with poor kidney allograft outcomes after the kidney transplant. Calcium oxalate (CaOx) deposition is common in early allograft biopsies leading to acute tubular necrosis and poor kidney allograft function. Though treatment options for secondary hyperoxaluria are limited, it is crucial to identify patients at increased risk of oxalate nephropathy after the transplant. RECENT FINDINGS: Recent data suggest that significant changes in renal replacement therapies and dietary modifications in high-risk patients can prevent kidney allograft damage from the calcium oxalate deposition leading to improve allograft outcomes. SUMMARY: The accurate and timely diagnosis of secondary oxalate nephropathy in kidney transplant recipients is paramount to preserving graft function in the long-term. This review will discuss the incidence, risk factors, prevention, and management of oxalate nephropathy in the kidney allograft.

Factors affecting sensitization following kidney allograft failure.

INTRODUCTION: Management of immunosuppression in a kidney transplant recipient with a failed allograft is complex; continuation carries infectious and metabolic risks, and discontinuation can lead to sensitization. METHODS: We evaluated risk factors for sensitization in 89 kidney or simultaneous kidney-pancreas recipients, whose kidney transplant failed after January, 2013 and who were subsequently re-evaluated for kidney transplantation. RESULTS: Among recipients with pre graft failure cPRA < 50%, calcineurin inhibitor (CNI) continuation (OR .11, P = .003) and steroid continuation (OR .17, P = .04) were associated with significantly lower odds of developing an absolute increase in cPRA of ≥50%. Each additional HLA mismatch was associated with OR of 2.16 (P = .02). CNI use was associated with OR of .09 (P = .001) for increase in cPRA to ≥80% if pre graft failure cPRA was <50%, and OR of .08 (P = .02) for increase in cPRA to ≥98% if pre graft cPRA was <80%. Anti-metabolites were continued more often among recipients who had a <50% increase (P = .006); however, the association was lost on multivariate analyses. Weaning off immunosuppression and higher number of HLA mismatches are associated with greater likelihood of sensitization. CONCLUSION: While both CNI and steroid continuation conferred some protection against increase in cPRA, CNI continuation was the only factor protecting against becoming highly sensitized.

Kidney transplant outcomes among recipients with post-transplant hip or knee joint replacement surgery.

INTRODUCTION: Patients with end-stage renal disease (ESRD) are at a higher risk of needing hip or knee replacement (joint replacement) surgery due to the high prevalence of degenerative joint disease and other conditions. However, there remains a large debate about the timing of joint replacement surgery and whether it should be pre- vs post-transplant. METHODS: We conducted a retrospective study analyzing all adult kidney transplant recipients (KTRs) at our university hospital who had undergone subsequent joint replacement between 2001 and 2017. Transplant-specific outcomes of acute rejection, death censored graft failure (DCGF), and patient death post-joint replacement surgery were outcomes of interest. Controls were selected at a 1:3 ratio based on the incidence density sampling of post-transplant interval. RESULTS: There were 101 KTRs in the joint replacement group and were compared with 281 controls. In the multivariate analysis, the need for joint replacement was not associated with acute rejection (HR: 1.59; 95% CI: 0.77-3.29; P = 0.21); DCGF (HR: 0.89; 95% CI: 0.49-1.60; P = 0.70) or patient death (HR: 0.84, 95% CI: 0.55-1.38, P = 0.42). CONCLUSION: In selected KTRs, joint replacement surgery was not associated with detrimental transplant-specific outcomes.

In kidney recipients from the same deceased donor, discordance in delayed graft function is associated with the worst outcomes.

INTRODUCTION: Delayed graft function (DGF) is a common complication among deceased donor kidney transplant recipients (DDKTs) and is associated with worse outcomes. The effect on outcomes of concordance versus discordance in DGF between two different recipients of kidneys from the same donor is largely unknown. METHODS: We reviewed all adult DDKTs for which both kidneys were transplanted to two different recipients at our center between 2014-2019. DDKTs were divided into four groups based on the DGF status: concordance no DGF (cc-no-DGF); discordance no DGF(dd-no-DGF); discordance DGF (dd-DGF) and concordance in DGF (cc-DGF). Acute rejection (AR) and death censored graft failure (DCGF) were outcomes of interest. RESULTS: A total of 578 DDKTs fulfilled our selection criteria, 280were in cc-no-DGF, 83 in dd-no-DGF, 83 in dd-DGF, and 132 in cc-DGF. Compared to cc-no-DGF, in univariate analysis, dd-DGF was associated with an increased risk of AR (HR: 1.60; 95% CI: 1.0-2.56) but cc-DGF was not (HR: 1.01; 95% CI: 0.63-1.62). dd-DGF was not associated with an increased risk of AR in multivariate analysis. In multivariate analysis, dd-DGF was associated with an increased risk of DCGF (HR: 2.70; 95% CI: 1.05-6.93) but cc-DGFwas not (HR: 2.36; 95% CI: 0.97-5.70). CONCLUSION: Discordance in DGF is associated with worse outcomes and may need closefollow-up and monitoring to improve the outcomes.

Risk factors and outcomes of BK viremia among deceased donor kidney transplant recipients based on donor characteristics.

INTRODUCTION: BK polyomavirus (BKV) is a common infection among kidney transplant recipients (KTR). Risk factors and outcomes based on donor characteristics remain largely unknown. METHODS: In this study, we aimed to analyze the impact of donor factors through a paired kidney analysis. We included 289 pairs of adult deceased donor transplants (578 KTRs total); each pair had received kidneys from the same donor. Recipient pairs were divided into three groups: "no BK group" if neither KTR developed BK viremia (n = 336), "discordant" if the only one did (n = 176), and "concordant" if both did (n = 66). Acute rejection (AR), graft failure, and BK nephropathy (BKN) were outcomes of interest. RESULTS: Donors in the concordant group were younger, had lower kidney donor profile index (KDPI), and were less likely to be donor after circulatory death (DCD). In multivariate analyses, KTRs who had a donor with a higher body mass index (BMI) (hazard ratio (HR): 0.97; 95% confidence interval (CI): 0.95-0.99; p = .009) were less likely to develop BKV. Concordance was not associated with AR (HR: 0.83; 95% CI: 0.51-1.34; p = .45), graft failure (HR: 1.77; 95% CI: 0.42-7.50; p = .43), or BKN (HR: 1.02; 95% CI: 0.51-2.03; p = .96). DISCUSSION: Our study suggests lower donor BMI is associated with BKV infection, and concordance or discordance between paired kidney recipients is not associated with poor outcomes.

Letermovir conversion after valganciclovir treatment in cytomegalovirus high-risk abdominal solid organ transplant recipients may promote development of cytomegalovirus-specific cell mediated immunity.

PURPOSE: To evaluate the association of conversion from valganciclovir to letermovir on cytomegalovirus-specific cellular immunity. METHODS: Adult patients were included if they received a kidney or liver transplant between 8/1/2018-12/31/20, developed symptomatic, high-level CMV viremia and were converted to letermovir 480 mg daily as monotherapy after treatment with ganciclovir-derivatives for a minimum of 4 weeks and had subsequent CMV cell-mediated immunity (CMI) testing via ICS assay by flow cytometry (Viracor Eurofins T Cell Immunity Panel). RESULTS: Seven patients met inclusion criteria; 87.5% were male and recipients of a kidney transplant. All patients were CMV high risk (D+/R-). Mean time from transplant to CMV disease was 200 ± 91 days. Peak viral load (VL) during CMV treatment was 540,341 ± 391,211 IU/mL. Patients received a mean of 30 ± 24 weeks (range: 4-78 weeks) of therapy with ganciclovir-derivatives at induction doses prior to letermovir introduction. The median absolute lymphocyte count (ALC) at letermovir initiation was 400/µL (IQR 575) and the median VL was 51.6 (range: ND-490) IU/mL. Most patients (n = 5/7, 71.4%) experienced an increase in VL 1 and/or 2 weeks after conversion to letermovir. All patients had positive CMI per ICS assay after conversion. Patients received a mean of 10.3 ± 6.9 weeks of letermovir prior to having a positive result. Median ALC at positivity was 900/µL. Immunosuppression was not further reduced from initiation of letermovir to demonstration of CMV CMI. No patient had progressive replication or breakthrough disease while maintained on letermovir and three patients (42.9%) underwent antiviral withdrawal without recurrence at the last follow-up. CONCLUSION: In this case series of abdominal transplant recipients with severe or persistent CMV infection, patients developed CMV-specific CMI after conversion to letermovir monotherapy. These data suggest that using letermovir in place of valganciclovir for secondary prophylaxis may address the lack of efficacy previously seen with this approach, as well as the issues that plague antiviral withdrawal with systematic monitoring. Future prospective studies are needed to evaluate this effect in a more controlled research environment with serial CMI testing to elucidate the optimal duration of letermovir when used in this way.

Patient characteristics, care patterns, and outcomes of atrial fibrillation associated hospitalizations in patients with chronic kidney disease and end-stage renal disease.

BACKGROUND: Chronic Kidney Disease (CKD) and end-stage renal disease (ESRD) are associated with poor outcomes in patients with cardiovascular disease. There is a paucity of contemporary data on in-hospital outcomes and care patterns of atrial fibrillation (AF) associated hospitalizations CKD and ESRD. METHODS: Outcomes and care patterns were evaluated in GWTG-AFIB database (Jan 2013-Dec 2018), including in-hospital mortality, use of a rhythm control strategy, and oral anticoagulation (OAC) prescription at discharge among eligible patients. Generalized logistic regression models with generalized estimating equations were used to ascertain differences in outcomes. Hospital-level variation in OAC prescription and rhythm control was also evaluated. RESULTS: Among 50,154 patients from 105 hospitals the median age was 70 years (interquartile range 61-79) and 47.3% were women. The prevalence of CKD was 36.0% while that of ESRD was 1.6%. Among eligible patients, discharge OAC prescription rates were 93.6% for CKD and 89.1% for ESRD. After adjustment, CKD and ESRD were associated with higher in-hospital mortality (odds ratio [OR] 3.08, 95% confidence interval [CI] 1.57-6.03 for ESRD and OR 2.02, 95% CI 1.52-2.67 for CKD), lower odds of OAC prescription at discharge (OR 0.59, 95% CI 0.44-0.79 for ESRD and OR 0.84, 95% CI 0.75-0.94 for CKD) compared with normal renal function. CKD was associated with lower utilization of rhythm control strategy (OR 0.92, 95% CI 0.87-0.98) with no significant difference between ESRD and normal renal function (OR 1.32, 95% CI 0.79-1.11). There was large hospital-level variation in OAC prescription at discharge (MOR 2.34, 95% CI 2.05-2.76) and utilization of a rhythm control strategy (MOR 2.69, 95% CI 2.34-3.21). CONCLUSIONS: CKD/ESRD is associated with higher in-hospital mortality, less frequent rhythm control, and less OAC prescription among patients hospitalized for AF. There is wide hospital-level variation in utilization of a rhythm control strategy and OAC prescription at discharge highlighting potential opportunities to improve care and outcomes for these patients, and better define standards of care in this patient population.

Transplant kidney biopsy for proteinuria with stable creatinine: Findings and outcomes.

INTRODUCTION: Little is known aboutbiopsy findings and outcomes when kidney transplant recipients (KTRs) undergo biopsy for isolated proteinuria with stable serum creatinine (SCr). METHODS: We analyzed all KTRs who underwent biopsy for isolated proteinuria with stable SCr between January 2016 and June 2020. Patients were divided into three groups based on the biopsy findings: Active Rejection (AR), Glomerulonephritis (GN), and Other. RESULTS: A total of 130 KTRs fulfilled our selection criteria; 38 (29%) in the AR group, 26 (20%) in the GN group, and 66 (51%) in the Other group. Most baseline characteristics were similar between the groups. In multivariate analysis, higher HLA mismatch (HR per mismatch: 1.30; 95% CI:1.06-1.59; P = .01) and male gender (HR: .45; 95% CI .23-.89; P = .02) were associated with AR. There was no significant correlation between the degree of proteinuria and rejection (r = .05, P = .58) or GN (r = .07, P = .53). Graft survival was also similar between the groups. Likely due to the early diagnosis without a significant rise in SCr, outcomes were similar among all three groups. CONCLUSION: Routine monitoring for proteinuria followed by a biopsy and appropriate management may help to identify early acute graft injury and prevent graft failure.

Incidence, risk factors, and outcomes of post-transplant erythrocytosis after kidney transplantation.

The incidence, risk factors, and outcomes of kidney transplant recipients (KTRs) with post-transplant erythrocytosis (PTE) in the modern era of strong, protocolized immunosuppressive management are unknown. In this study, we aim to identify the incidence and risk factors of PTE and outcomes associated with PTE. This study examined adult KTRs transplanted at our hospital between 01/2001 and 12/2016. Controls were KTRs without PTE and selected in a 1:5 ratio using incident density sampling. Patient survival, graft survival, and vascular thromboembolism (VTE) incidence were outcomes of interest. Of 4,317 kidney transplants during the study period, 214 (5%) had PTE and were compared with controls. In the multivariate analysis, recipients with older age (HR: 0.97, 95% CI 0.96-0.99, p = .001) were less likely to develop PTE, while male gender (HR: 3.2; 95% CI: 1.92-5.3, p < .001) and non-preemptive transplant (HR: 3.86, 95% CI 1.56-9.56, p = .003) were associated with increased risk of PTE. After adjustment for confounding factors, PTE was not associated with patient mortality (HR: 0.99, 95% CI 0.69-1.42, p = .97), graft failure (HR: 1.11, 95% CI 0.68-1.80, p = .69), or VTE (HR: 1.07, 95% CI 0.59-1.96, p = .81). The incidence of PTE is still substantial in this era, but with proper management PTE does not impact patient or graft survival.

Discrepant subtyping of blood type A2 living kidney donors: Missed opportunities in kidney transplantation.

BACKGROUND: Despite the institution of a new Kidney Allocation System in 2014, A2/A2B to B transplantation has not increased as expected. The current Organ Procurement and Transplantation Network policy requires subtyping on two separate occasions, and in the setting of discrepant results, defaulting to the A1 subtype. However, there is significant inherent variability in the serologic assays used for blood group subtyping and genotyping is rarely done. METHODS: The National Kidney Registry, a kidney paired donation (KPD) program, performs serological typing on all A/AB donors, and in cases of non-A1/non-A1B donors, confirmatory genotyping is performed. RESULTS: Between 2/18/2018 and 9/15/2020, 13.0% (145) of 1,111 type A donors registered with the NKR were ultimately subtyped as A2 via genotyping. Notably, 49.6% (72) of these were subtyped as A1 at their donor center, and in accordance with OPTN policy, ineligible for allocation as A2. CONCLUSION: Inaccurate A2 subtyping represents a significant lost opportunity in transplantation, especially in KPD where A2 donors can not only facilitate living donor transplantation for O and highly sensitized candidates, but can also facilitate additional living donor transplants. This study highlights the need for improved accuracy of subtyping technique, and the need for policy changes encouraging optimal utilization of A2 donor kidneys.

A pilot study of an intensified ganciclovir dosing strategy for treatment of cytomegalovirus disease in kidney and/or pancreas transplant recipients.

PROBLEM: Mathematical modeling suggests aggressive ganciclovir dosing in the first week of cytomegalovirus disease (CMV) treatment may improve response. This has not been evaluated clinically. METHODS: Adult kidney and/or pancreas transplant recipients admitted with CMV (4/29/19-7/15/20) received IV ganciclovir(10 mg/kg Q12 h × 7 days) with step-down to standard-of-care (SOC) dosing thereafter (5 mg/kg Q12). A SOC cohort admitted before implementation of the dosing strategy (10/20/16-3/2/19) served as a comparator. PRIMARY OBJECTIVE: rate of viral clearance (delta log CMV) at therapy day 7. SECONDARY OBJECTIVE: safety/short term efficacy. RESULTS: Fifty-four patients met inclusion criteria; 22 high-dose, 32 SOC. Demographics were similar with the exception of more women (45.4% vs. 15.6%,P = .03) and higher presenting viral-load in the high-dose group (log 6.0±.7 vs. log 5.2±1.2, P = .02). High-dose resulted in significantly greater response to therapy at day 7 (log -.92±.51 vs. log -.56±.79, P = .04). Change in WBC at day 7 was not different (-.49±1.92 vs. -.45±5.1, P = .97). Short-term clinical outcomes were similar between groups including mean hospital length-of-stay (P = .52), readmission rates (30 d: P = .38; 90 d: P = .5) and achievement of CMV viral-load less-than-lower-limit-of-quantification by day 90 (73% vs. 84%, P = .06). Rejection after CMV as well as graft/patient survival were similar between groups (P = .56, P > .99, P > .99). CONCLUSION: A high-dose IV ganciclovir strategy results in improved viral clearance kinetics without safety concerns and similar short term clinical outcomes.

Post-kidney transplant serum magnesium exhibits a U-shaped association with subsequent mortality: an observational cohort study.

Hypomagnesemia is common in kidney transplant recipients (KTRs). We sought to explore the relationship between Mg and outcomes in KTRs, which may be associated with mortality and thus may be a potential intervention target to improve outcomes. We followed KTRs performed between 01/2000 and 6/2016 at a large US transplant center from 6 months post-transplant to graft failure, death, or loss to follow-up. Using Mg as a time-dependent variable, associations between Mg and outcomes any time after 6 months post-transplant were evaluated. 3680 KTRs with 50  413 Mg measurements met inclusion criteria. 657 deaths occurred over a median follow-up of 5.1 years. Compared to Mg of 1.5-1.8 mg/dl, both lower (HR 1.17, 95% confidence interval (CI): 1.07-1.28) and higher (HR 1.16, 95% CI: 1.09-1.23) Mg levels were associated with greater risk of mortality. Similar U-shaped associations were observed for Mg and cardiovascular disease-related mortality (HR for Mg ≤1.5 mg/dl: 1.31; CI: 1.03-1.68) and infection-related mortality (HR for Mg ≤1.5 mg/dl: 1.28; CI: 1.09-1.51), although relationships for Mg >1.8 mg/dl were not statistically significant. Mg exhibits a U-shaped association with mortality in KTRs, with levels between 1.5 and 1.8 mg/dl associated with the lowest risk.