Recommendations for the outpatient surveillance of renal transplant recipients. American Society of Transplantation

Incidence, Risk Factors, and Outcomes of Posttransplant Erythrocytosis Among Simultaneous Pancreas-Kidney Transplant Recipients

Background

Posttransplant erythrocytosis (PTE) is a well-known complication of kidney transplantation. However, the risk and outcomes of PTE among simultaneous pancreas-kidney transplant (SPKT) recipients are poorly described.

Methods

We analyzed all SPKT recipients at our center between 1998 and 2021. PTE was defined as at least 2 consecutive hematocrit levels of >51% within the first 2 y of transplant. Controls were selected at a ratio of 3:1 at the time of PTE occurrence using event density sampling. Risk factors for PTE and post-PTE graft survival were identified.

Results

Of 887 SPKT recipients, 108 (12%) developed PTE at a median of 273 d (interquartile range, 160-393) after transplantation. The incidence rate of PTE was 7.5 per 100 person-years. Multivariate analysis found pretransplant dialysis (hazard ratio [HR]: 3.15; 95% confidence interval [CI], 1.67-5.92; P < 0.001), non-White donor (HR: 2.14; 95% CI, 1.25-3.66; P = 0.01), female donor (HR: 1.50; 95% CI, 1.0-2.26; P = 0.05), and male recipient (HR: 2.33; 95% CI, 1.43-3.70; P = 0.001) to be associated with increased risk. The 108 cases of PTE were compared with 324 controls. PTE was not associated with subsequent pancreas graft failure (HR: 1.36; 95% CI, 0.51-3.68; P = 0.53) or kidney graft failure (HR: 1.16; 95% CI, 0.40-3.42; P = 0.78).

Conclusions

PTE is a common complication among SPKT recipients, even in the modern era of immunosuppression. PTE among SPKT recipients was not associated with adverse graft outcomes, likely due to appropriate management.

Risk factors and current state of therapy for anemia after kidney transplantation

Post-transplant anemia is one of the most common complications in kidney transplant recipients, severely affecting patient prognosis and quality of life, and is an independent predictor of graft kidney loss and patient mortality. However, our clinical understanding and the attention given to post-transplant anemia are currently insufficient. This paper reviews the current status, risk factors, and therapeutic progress in anemia after transplantation in kidney transplant recipients. We recommend that clinical staff pay attention to anemia and its complications in kidney transplant recipients and intervene early for anemia.

A case of bladder cancer after bilateral lung transplantation following bone marrow transplantation

Introduction

The incidence of bladder cancer following transplantation is high; however, no previous studies have reported the development of bladder cancer following bone marrow and bilateral lung transplantations.

Case presentation

A 42-year-old man who was followed for bilateral lung transplantation due to chronic graft-versus-host disease following bone marrow transplantation complained of gross hematuria. Transurethral resection of the bladder tumor was performed for cT1N0M0 bladder cancer. On the following night, he experienced severe respiratory failure and was intubated. He was discharged on postoperative day 32 with the introduction of home oxygen therapy. The pathological diagnosis was invasive urothelial carcinoma, high-grade, pT1, with urothelial carcinoma in situ. Further treatment could not be performed because of his poor performance status and immunosuppressive state.

Conclusion

Vigorous screening for bladder cancer coexisting with other malignancies should be performed for transplant recipients for the early diagnosis and prompt treatment of a relatively aggressive bladder cancer.

The role of localised prostate cancer treatment in renal transplant patients: A systematic review

Objective

To systematically review and critically appraise all treatment options for localised prostate cancer in renal transplant candidates and recipients.

Method

A systematic review was conducted adhering to PRISMA guidelines. Searches were performed in the Cochrane Library, Embase, Medline, the Transplant Library and Trip database for studies published up to September 2022. Risk of bias was assessed with the Cochrane Risk of Bias in Non-Randomised Studies of Interventions for non-randomised studies tool.

Results

A total of 60 studies were identified describing 525 patients. The majority of studies were either retrospective non-randomised comparative or case series/reports of poor quality. The vast majority of studies were focussed on prostate cancer after renal transplantation. Overall, 410 (78%) patients underwent surgery, 93 (18%) patients underwent radiation therapy or brachytherapy, one patient underwent focal therapy (high-intensity frequency ultrasound) and 21 patients were placed on active surveillance. The mean age was 61 years old, the mean PSA level at diagnosis was 9.6 ng/mL and the mean follow-up time was 31 months. The majority of patients had low-risk disease with 261 patients having Gleason 6 prostate cancer (50%), followed by 220 Gleason 7 patients (42%). All prostate cancer mortality cases were in high-risk prostate cancer (≥Gleason 8). The cancer-specific survival results were similar between surgery and radiotherapy at 1 and 3 years.

Conclusion

Localised prostate cancer treatment in renal transplant patients should be risk stratified. Surgery and radiation treatment for localised prostate cancer in renal transplant patients appear equally efficacious. Given the limitations of this study, future research should concentrate on developing a multicentre RCT with long-term registry follow-up.

Weight-based vs fixed dosing of darbepoetin alfa for anemia following kidney transplantation

PURPOSE

Post-transplantation anemia (PTA) is common in kidney transplant recipients, with patients frequently treated with erythropoietin-stimulating agents such as darbepoetin alfa. The optimal dosing for darbepoetin alfa remains controversial.

METHODS

This retrospective cohort study involved kidney transplant recipients who received darbepoetin alfa at 2 clinics. Patients were stratified into 2 groups: those who received a fixed dose of 200 μg and those who received a weight-based dose of 0.45 μg/kg. The dosing interval varied depending on clinical response, clinic visit timing, and frequency allowed by insurance. The primary outcome was achieving a hemoglobin concentration of at least 10 g/dL without blood transfusion by 12 weeks after darbepoetin alfa initiation.

RESULTS

Of the 110 patients in the study, 45% received weight-based dosing and 55% received fixed dosing. Darbepoetin alfa was initiated significantly earlier after transplantation in the fixed-dose group (median of 14 vs 20 days; P = 0.003). The weight-based group received more doses of darbepoetin alfa (median of 4 vs 2 doses; P = 0.002) and had a significantly lower cumulative exposure to darbepoetin alfa (125 vs 590 μg; P < 0.001). The median time between doses was 9 days (interquartile range, 7-14 days) in the weight-based group and 12 days (7-32 days) in the fixed-dose group (P = 0.04). Patients in the weight-based group more frequently achieved the primary outcome (67.3% vs 47.5%; P = 0.059). There was no significant difference in secondary or safety outcomes between the groups.

CONCLUSION

Weight-based and fixed dosing approaches for darbepoetin alfa were not different in the achievement of a hemoglobin concentration of at least 10 g/dL without blood transfusion at 12 weeks after darbepoetin alfa initiation, with significantly lower cumulative darbepoetin alfa utilization in the weight-based group. Weight-based dosing of darbepoetin alfa in PTA appears to be safe and effective, with the potential for significant patient and health-system cost savings.

Anemia after kidney transplantation

Anemia is a frequent complication in pediatric kidney transplant recipients (KTR) with a variable reported prevalence estimated between 20 and 80% depending on how defined. Causes of and risk factors for post-transplantation anemia (PTA) are multifactorial with iron deficiency being the primary cause of early PTA (within the first 6 months after transplantation) and impaired glomerular filtration rate (GFR) commonly responsible for late PTA (after 6 months). Medications, viral infections, chronic inflammation, and comorbidities also play a role. PTA has relevant long-term consequences and is a potential risk factor for allograft dysfunction, cardiovascular morbidity, and mortality. Thus, an anemia evaluation, approximately 3 months post-transplantation, is recommended in order to start early treatment and improve prognosis. Iron status, vitamin B12, folate, markers of hemolysis, and viral PCR should be checked, and medications, in particular combinations of medications, should be carefully evaluated. PTA treatment may be challenging and should be directed to the underlying causes. Iron supplementation and erythropoietin therapy, not extensively used in KTR, may be indicated. Every effort should be made to avoid blood transfusions in the pre-transplant period to avoid allosensitization. Anemia should be corrected to prepare candidates for kidney transplantation in order to reduce the need for perioperative blood transfusions as well.

Early referring saved lives in kidney transplant recipients with COVID-19: a beneficial role of telemedicine

Introduction

There is a strong impetus for the use of telemedicine for boosting early detection rates and enabling early treatment and remote monitoring of COVID-19 cases, particularly in chronically ill patients such as kidney transplant recipients (KTRs). However, data regarding the effectiveness of this practice are lacking.

Methods

In this retrospective, observational study with prospective data gathering we analyzed the outcomes of all confirmed COVID-19 cases (n = 955) in KTRs followed at our center between March 1, 2020, and April 30, 2022. Risk factors of COVID-19 related mortality were analyzed with focus on the role of early referral to the transplant center, which enabled early initiation of treatment and remote outpatient management. This proactive approach was dependent on the establishment and use of a telemedicine system, which facilitated patient-physician communication and expedited diagnostics and treatment. The main exposure evaluated was early referral of KTRs to the transplantation center after confirmed or suspected COVID-19 infection. The primary outcome was the association of early referral to the transplantation center with the risk of death within 30 days following a COVID-19 diagnosis, evaluated by logistic regression.

Results

We found that KTRs who referred their illness to the transplant center late had a higher 30-day mortality (4.5 vs. 13.6%, p < 0.001). Thirty days mortality after the diagnosis of COVID-19 was independently associated with late referral to the transplant center (OR 2.08, 95% CI 1.08-3.98, p = 0.027), higher age (OR 1.09, 95% CI 1.05-1.13, p < 0.001), higher body mass index (OR 1.06, 95% CI 1.01-1.12, p = 0.03), and lower eGFR (OR 0.96, 95% CI 0.94-0.98, p < 0.001) in multivariable logistic regression. Furthermore, KTRs who contacted the transplant center late were older, had longer time from transplantation, lived farther from the center and presented with higher Charlson comorbidity index.

Discussion

A well-organized telemedicine program can help to protect KTRs during an infectious disease outbreak by facilitating pro-active management and close surveillance. Furthermore, these results can be likely extrapolated to other vulnerable populations, such as patients with chronic kidney disease, diabetes or autoimmune diseases requiring the use of immunosuppression.

Evolving Landscape in Liver Transplantation for Hepatocellular Carcinoma: From Stage Migration to Immunotherapy Revolution

Liver transplantation (LT) represents the primary curative option for HCC. Despite the extension of transplantation criteria and conversion with down-staging loco-regional treatments, transplantation is not always possible. The introduction of new standards of care in advanced HCC including a combination of immune checkpoint inhibitor-based therapies led to an improvement in response rates and could represent a promising strategy for down-staging the tumor burden. In this review, we identify reports and series, comprising a total of 43 patients who received immune checkpoint inhibitors as bridging or down-staging therapies prior to LT. Overall, treated patients registered an objective response rate of 21%, and 14 patients were reduced within the Milan criteria. Graft rejection was reported in seven patients, resulting in the death of four patients; in the remaining cases, LT was performed safely after immunotherapy. Further investigations are required to define the duration of immune checkpoint inhibitors, their minimum washout period and the LT long-term safety of this strategy. Some randomized clinical trials including immunotherapy combinations, loco-regional treatment and/or tyrosine kinase inhibitors are ongoing and will likely determine the appropriateness of immune checkpoint inhibitors' administration before LT.

Uncontrolled hypertension is associated with increased risk of graft failure in kidney transplant recipients: a nationwide population-based study

Backgroud

Hypertension is highly prevalent in patients with kidney transplantation caused by transplantation-related immunologic or non-immunologic risk factors. However, whether a strict definition of hypertension (≥130/80 mmHg) and subdivided blood pressure (BP) groups are associated with an increased risk of graft failure after kidney transplantation using a nationwide large cohort study are still unknown.

Methods

Using Korean National Health Insurance Service data, we included 14,249 patients who underwent kidney transplantation from 2002 to 2016. Patients were categorized into five BP groups according to the 2021 Kidney Disease: Improving Global Outcomes practice guidelines for BP management: normal BP (<120/80 mmHg), elevated BP (120-129/ < 80 mmHg), incident hypertension (≥130/80 mmHg), and controlled or uncontrolled hypertension with anti-hypertensive medications.

Results

The primary outcome was graft failure, which occurred in 1934 (13.6%) participants during the 6-year follow-up. After adjusting for covariates, hypertension was associated with a higher risk of graft failure [Adjusted hazard ratio (AHR), 1.70; 95% confidence interval (CI), 1.48-1.96)] than no-hypertension. The AHR for graft failure was the highest in patients with uncontrolled hypertension (AHR, 2.13; 95% CI, 1.80-2.52). The risk of graft failure had a linear relationship with systolic and diastolic BP, and pulse pressure.

Conclusions

In this nationwide population-based study, hypertension ≥130/80 mmHg based on the 2021 KDIGO BP guidelines in kidney transplantion recipients, and elevated systolic and diastolic BP, and pulse pressure were associated with the risk of developing graft failure in kidney transplant recipients.

Incidence and Factors Associated with Uncontrolled Hypertension at 12 months after Kidney Transplantation in Saudi Arabia

INTRODUCTION

Uncontrolled blood pressure (uBP) after kidney transplantation (KTx) is very common and is associated with significant morbidity. However, studies that assess its incidence and risk factors are limited and outdated in the Middle East.

METHODS

This is a single-center retrospective study of KTx recipients (KTRs) in our center between January 2017 and May 2020 with a 12-month follow-up period. The target of hypertension treatment during the time of this study was <140/90 mm Hg, according to the published guidelines. We divided patients according to their blood pressure (BP) control at 1 year into two groups: controlled BP (cBP) (<140/90) and uBP (≥140/90). We studied the association between uBP and patients' demographics, baseline cardiovascular risk factors, and changes in their metabolic and cardiovascular profile during the first 12 months post-KTx.

RESULTS

A total of 254 KTRs were included. 79.2% developed post-KTx hypertension, 74% were ≥30 years, 58% were men, and 80% were living donor KTRs. The renal replacement modality among our patients pre-KTx was hemodialysis in 78.4%, peritoneal dialysis in 11.5%, and 10.1% underwent preemptive transplantation. At 1 year, 76 (29.9%) KTRs did not attain the target BP goal. Systolic BP (SBP) decreased from baseline to 12 months by 13 ± 24 mm Hg in the cBP group and increased by 8.7 ± 21 mm Hg in the uBP group (p < 0.001). Additionally, diastolic BP (DBP) decreased by 8.5 ± 16.9 mm Hg in the cBP group and increased by 2.3 ± 18.8 mm Hg in the uBP group (p < 0.001). Factors associated with uBP included age (47 vs. 41 years, p = 0.008) and diabetes mellitus (p = 0.012). Contrarily, gender, dialysis vintage, preemptive transplantation, type of dialysis (hemodialysis vs. peritoneal dialysis), type of transplant (living donor KTx vs. deceased donor KTx), and smoking were not different among the two groups. There were no significant differences between the two groups in regard to changes in creatinine, weight, A1c, low-density lipoprotein, and parathyroid hormone levels. Additionally, rate of rejection, new onset diabetes post-transplant, and persistent hyperthyroidism were not different between the groups. However, higher body mass index at 12 months was associated with a higher incidence of uBP (27.2 ± 5.9 vs. 29.2 ± 5.4, p = 0.013). Using multivariate analysis, we found that serum creatinine at 12 months was the only predictor of uBP (OR = 1.005 [1-1.011], p = 0.036).

CONCLUSION

At 1-year post-renal transplantation, about one-third of KTRs had uBP despite multiple antihypertensive medications. SBP and DBP significantly trended upward after transplantation in uBP patients, whereas SBP and DBP significantly trended downward after transplantation in cBP patients. Serum creatinine at 12 months was the only factor independently associated with uBP.

The Trend of Serum Creatinine Does Not Predict Follow-Up Biopsy Findings Among Kidney Transplant Recipients With Antibody-Mediated Rejection

Traditionally, antibody-mediated rejection (AMR) has been suspected mainly by a rise in serum creatinine (Scr) and confirmed by allograft biopsy. There is limited literature describing the trend of Scr after treatment, and how that trend might differ between patients with histological response and with no response to treatment.

Methods

We included all cases of AMR at our program between March 2016 and July 2020 who had a follow-up biopsy after the index biopsy, with initial diagnosis of AMR. We trended the Scr and change in Scr (delta Scr) and its association with being a responder (microvascular inflammation, MVI ≤1) or nonresponder (MVI >1), as well as graft failure.

Results

A total of 183 kidney transplant recipients were included, 66 in the responder group and 177 in the nonresponder group. The MVI scores and sum chronicity scores, along with transplant glomerulopathy scores, were higher in the nonresponder group. However, Scr at index biopsy was similar in responders (1.74 ± 0.70) versus nonresponders (1.83 ± 0.65; P = 0.39), as were the delta Scr at various time points. After adjustment for multiple variables, delta Scr was not associated with being a nonresponder. Also, delta Scr value at follow-up biopsy compared with index biopsy among responders was 0 ± 0.67 (P = 0.99) and among nonresponders was -0.01 ± 0.61 (P = 0.89). Being a nonresponder was significantly associated with an increased risk of graft failure at the last follow-up in univariate analysis but was not in multivariate analysis (hazard ratio 1.35; 95% confidence interval, 0.58-3.17; P = 0.49).

Conclusions

We found that Scr is not a good predictor of the resolution of MVI, supporting the utility of follow-up biopsies after treatment of AMR.

A Study Protocol Exploring the Role of an Implantable Doppler Probe in Kidney Transplantation: A Feasibility Randomized Controlled Trial with an Embedded Qualitative Study

OBJECTIVES

Vascular complications in kidney transplant surgery constitute one-third of early graft loss, which can be prevented by timely diagnosis of vascular compromise. A blood flow monitoring device may have a beneficial role in the early identification of graft hypoperfusion critical to reducing graft loss. This research protocol aims to evaluate the potential of an implantable Doppler probe as a blood flow monitoring device in kidney transplant recipients.

MATERIALS AND METHODS

The potential study will be a mixed methodology, 2-arm feasibility randomized controlled trial with an embedded qualitative study. For the trial, we will compare demographic characteristics and outcome measures of kidney transplant patients receiving implantable Doppler probe monitoring (intervention group, n = 30) with those having standard clinical care (control group). For the qualitative study, we will conduct semi-structured interviews with stakeholders (n = 12) recruited by purposive sampling to explore experiences of participants. All interviews will be audio recorded with verbatim transcription.

RESULTS

Our results will use the summarized quantitative data and descriptive statistics to determine differences between the groups. We will use CONSORT guidelines to determine the suitability of the research processes, availability of research resources, and potential challenges faced during the feasibility randomized controlled trial. We will use thematic analysis and NVivo software to analyze the acceptability of the intervention in clinical practice. We will compile the results according to the consolidated criteria for reporting qualitative research checklist.

CONCLUSIONS

The goal of this protocol is to determine the feasibility of an implantable Doppler probe monitoring device in kidney transplant recipients. The feasibility study will collect preliminary information, fill gaps in evidence, and test research processes for the pragmatic future randomized controlled trial. The template of this study is transferable to other transplant centers across the United Kingdom.

Human papillomavirus anogenital screening in solid organ transplant recipients: a narrative review

PURPOSE

To provide a narrative review of anogenital screening for human papillomavirus in solid organ transplant recipients.

METHODS

Keyword searches of PubMed and Ovid MEDLINE databases were performed. Keywords included human papillomavirus, malignancy, cervical cancer, Pap smear, solid organ transplant, and immunosuppression. Manual searches were also conducted of other relevant journals and reference lists of primary articles.

RESULTS

Forty-one studies, articles, or clinical practice guidelines across 25 years of literature were included. Eligible literature was written in English or offered an English translation.

CONCLUSION

Human papillomavirus-related anogenital malignancies disproportionately affect transplant recipients compared to the general population. Evidence-based guidelines for cervical cancer screening and prevention in transplant patients are lacking. Current practice guidelines generally agree on increased Pap screening for transplant recipients compared to the general population. However, recommended screening frequency differs between organizations and amongst medical specialties. Vaccination against HPV remains the most effective strategy to prevent HPV-driven pre-malignant and malignant lesions.

A Systematic Review and Meta-Analysis of Posttransplant Anemia With Overall Mortality and Cardiovascular Outcomes Among Kidney Transplant Recipients

Introduction: Posttransplant anemia is a common finding after kidney transplantation. A previous meta-analysis reported an association between anemia and graft loss. However, data on cardiovascular outcomes have not yet been reported. Objective: We conducted an updated meta-analysis to examine the association between posttransplant anemia and outcomes after transplantation including cardiovascular mortality in adult kidney transplant recipients. Methods: We comprehensively searched the databases of MEDLINE and EMBASE from inception to November 2021. Data from each study were combined using the random-effects model. Generic inverse variance method of DerSimonian and Laird was employed to calculate the risk ratios and 95% CIs. Results: Seventeen studies from August 2006 to April 2019 were included (16 463 kidney transplantation recipients). Posttransplant anemia was associated with overall mortality (pooled risk ratio = 1.72 [1.39, 2.13], I² = 56%), graft loss (pooled risk ratio = 2.28 [1.77, 2.93], I² = 94%), cardiovascular death (pooled risk ratio = 2.06 [1.35, 3.16], I² = 0%), and cardiovascular events (pooled risk ratio = 1.33 [1.10, 1.61], I² = 0%). Early anemia (≤6 months), compared with late anemia (>6 months), has higher risk of overall mortality and graft loss with a pooled risk ratio of 2.63 (95% CI 1.79-3.86; I² = 0%) and 2.96 (95% CI 2.29-3.82; I² = 0%), respectively. Discussion: In addition to increased risk of graft loss, our updated meta-analysis demonstrated that posttransplant anemia was significantly associated with poor outcomes after kidney transplantation including overall mortality, graft loss, cardiovascular death, and cardiovascular events. Future studies are required to assess the effects of treatment strategies for posttransplant anemia on posttransplant outcomes including cardiovascular mortality.

External Validation of the Skin and UV Neoplasia Transplant Risk Assessment Calculator (SUNTRAC) in a Large European Solid Organ Transplant Recipient Cohort

Importance

The Skin and UV Neoplasia Transplant Risk Assessment Calculator (SUNTRAC) tool has been developed in the US to facilitate the identification of solid organ transplant recipients (SOTRs) at a higher risk of developing skin cancer. However, it has not yet been validated in populations other than the one used for its creation.

Objective

To provide an external validation of the SUNTRAC tool in different SOTR populations.

Design, Setting, and Participants

This retrospective external validation prognostic study used data from a prospectively collected cohort of European SOTRs from transplant centers at teaching hospitals in the Netherlands (1995-2016) and Spain (2011-2021). Participants were screened and followed up at dermatology departments. Data were analyzed from September to October 2021.

Main Outcomes and Measures

The discrimination ability of the SUNTRAC tool was assessed via a competing risk survival analysis, cumulative incidence plots, and Wolbers concordance index. Calibration of the SUNTRAC tool was assessed through comparison of projected skin cancer incidences. Skin cancer diagnoses included squamous cell carcinoma, basal cell carcinoma, melanoma, and Merkel cell carcinoma.

Results

A total of 3421 SOTRs (median age at transplant, 53 [quartile 1: 42; quartile 3: 62] years; 2132 [62.3%] men) were assessed, including 72 Asian patients (2.1%), 137 Black patients (4.0%), 275 Latinx patients (8.0%), 109 Middle Eastern and North African patients (3.2%), and 2828 White patients (82.7%). With a total of 23 213 years of follow-up time, 603 patients developed skin cancer. The SUNTRAC tool classified patients into 4 groups with significantly different risks of developing skin cancer during follow-up. Overall, the relative rate for developing skin cancer estimated using subdistribution hazard ratios (SHRs) and using the low-risk group as the reference group, increased according to the proposed risk group (medium-risk group: SHR, 6.8 [95% CI, 3.8-12.1]; P < .001; high-risk group: SHR, 15.9 [95% CI, 8.9-28.4]; P < .001; very-high-risk group: SHR, 54.8 [95% CI, 29.1-102.9]; P < .001), with a concordance index of 0.72. Actual skin cancer incidences were similar to those predicted by the SUNTRAC tool (5-year skin cancer cumulative incidence for medium-risk group: predicted, 6.2%; observed, 7.0%).

Conclusions and Relevance

The findings of this external validation prognostic study support the use of the SUNTRAC tool in European populations for stratifying SOTRs based on their skin cancer risk and also detecting patients at a high risk of developing skin cancer. This can be helpful in prioritizing and providing better screening and surveillance for these patients.

The combination of exposure to Tacrolimus, mycophenolic acid, Inosine 5'-Monophosphate Dehydrogenase activity and inhibition in the first week define early histological outcomes in renal transplant recipients

Therapeutic drug monitoring is routine for Tacrolimus, while levels are not routinely monitored for mycophenolic acid (MPA). This study investigated the effect of early post-transplant pharmacokinetics (PK) of MPA and Tacrolimus along with the pharmacodynamics (PD) of MPA on biopsy-proven acute rejection (BPAR) after renal transplantation. A prospective PK/PD study with limited sampling (three blood samples) was conducted in renal transplant recipients on week 1, around Day 6 (n = 42) and at the 3rd-month biopsy on Day 90 (n = 23). The partial exposures (area under curve [AUC]_0-3.5 h ) of both MPA and Tacrolimus obtained during the first week were more predictive of rejection (combined clinical and subclinical rejection) by Day 90 than their trough concentrations or Day 90 exposures. Patients with rejection had significantly worse renal function (eGFR) and a comparatively lower exposure to MPA during the first post-transplant week. The lower MPA exposure was also associated with sub-optimal inosine monophosphate dehydrogenase (IMPDH) inhibition in patients with rejection, and the probability of rejection was higher in the presence of an increased pre-transplant IMPDH activity. A composite of parameters, including MPA exposure and IMPDH activity was found to predict acute rejection and may be beneficial along with tacrolimus monitoring early after renal transplantation.

Prevalence of Post-Heart Transplant Malignancies: A Systematic Review and Meta-Analysis

The prevalence of different cancers after heart transplant (HT) is unclear due to small and conflicting prior studies. Herein, we report a systematic review and meta-analysis to highlight the prevalence and pattern of malignancies post-HT. We conducted an extensive literature search on PubMed, Scopus, Cochrane databases for prospective or retrospective studies reporting malignancies after HT. The proportions from each study were subjected to random effects model that yielded the pooled estimate with 95% confidence intervals (CI). Fifty-five studies comprising 60,684 HT recipients reported 7,759 total cancers during a mean follow-up of 9.8 ± 5.9 years, with an overall incidence of 15.3% (95% CI = 12.7%-18.1%). Mean time from HT to cancer diagnosis was 5.1 ± 4 years. The most frequent cancers were gastrointestinal (7.6%), skin (5.7%), and hematologic/blood (2.5%). Meta-regression showed no association between incidence of cancer and mean age at HT (coeff: -0.008; p=0.25), percentage of male recipients (coeff: -0.001; p=0.81), donor age (coeff: -0.011; p=0.44), 5-year (coeff: 0.003; p=0.12) and 10-year (coeff: 0.02; p=0.68) post-transplant survival. There is a substantial risk of malignancies in HT recipients, most marked for gastrointestinal, skin, and hematologic. Despite their occurrence, survival is not significantly impacted.

The diagnostic value of Doppler ultrasonography after pediatric kidney transplantation

Ultrasonography (US) plays a major diagnostic role in the pre- and post-transplant evaluation of recipient and donor. In most cases, US remains the only necessary imaging modality. After pediatric kidney transplantation, US can ensure immediate bedside diagnosis of vessel patency and possible postoperative non-vascular complications. Criteria for US diagnosis of kidney vessel thrombosis and stenosis in the transplant will be presented. Non-vascular complications after kidney transplantation include hydronephrosis, hematoma, lymphocele, and abscess. US can detect suggestive, but nevertheless non-specific, acute signs (sudden increase in volume and elevated resistive index), and chronic rejection, which therefore remains a histological diagnosis. US is of little or no help in detection of tubular necrosis or drug toxicity, but it can exclude other differential diagnoses. This educational review provides a practical and systematic approach to a multimodal US investigation of the kidney transplant. It includes a short overview on possible indications for contrast-enhanced ultrasonography (CEUS) in children after kidney transplantation.

Pediatric Onco-Nephrology: Time to Spread the Word-Part II: Long-Term Kidney Outcomes in Survivors of Childhood Malignancy and Malignancy after Kidney Transplant

Onco-nephrology is a recent and evolving medical subspecialty devoted to the care of patients with kidney disease and unique kidney-related complications in the context of cancer and its treatments, recognizing that management of kidney disease as well as the cancer itself will improve survival and quality of life. While this area has received much attention in the adult medicine sphere, similar emphasis in the pediatric realm has not yet been realized. As in adults, kidney involvement in children with cancer extends beyond the time of initial diagnosis and treatment. Many interventions, such as chemotherapy, stem cell transplant, radiation, and nephrectomy, have long-term kidney effects, including the development of chronic kidney disease (CKD) with subsequent need for dialysis and/or kidney transplant. Thus, with the improved survival of children with malignancy comes the need for ongoing monitoring of kidney function and early mitigation of kidney-related comorbidities. In addition, children with kidney transplant are at higher risk of developing malignancies than their age-matched peers. Pediatric nephrologists thus need to be aware of issues related to cancer and its treatments as they impact their own patients. These facts emphasize the necessity of pediatric nephrologists and oncologists working closely together in managing these children and highlight the importance of bringing the onco-nephrology field to our growing list of pediatric nephrology subspecialties.

Magnetic Resonance Elastography-derived Stiffness Predicts Renal Function Loss and Is Associated With Microvascular Inflammation in Kidney Transplant Recipients

Background.

Organ stiffening can be caused by inflammation and fibrosis, processes that are common causes of transplant kidney dysfunction. Magnetic resonance elastography (MRE) is a contrast-free, noninvasive imaging modality that measures kidney stiffness. The objective of this study was to assess the ability of MRE to serve as a prognostic factor for renal outcomes.

Methods.

Patients were recruited from the St Michael’s Hospital Kidney Transplant Clinic. Relevant baseline demographic, clinical, and Banff histologic information, along with follow-up estimated glomerular filtration rate (eGFR) data, were recorded. Two-dimensional gradient-echo MRE imaging was performed to obtain kidney “stiffness” maps. Binary logistic regression analyses were performed to examine for relationships between stiffness and microvascular inflammation score. Linear mixed-effects modeling was used to assess the relationship between stiffness and eGFR change over time controlling for other baseline variables. A G²-likelihood ratio Chi-squared test was performed to compare between the baseline models with and without “stiffness.”

Results.

Sixty-eight transplant kidneys were scanned in 66 patients (mean age 56 ± 12 y, 24 females), with 38 allografts undergoing a contemporaneous biopsy. Mean transplant vintage was 7.0 ± 6.8 y. In biopsied allografts, MRE-derived allograft stiffness was associated only with microvascular inflammation (Banff g + ptc score, Spearman ρ = 0.43, P = 0.01), but no other histologic parameters. Stiffness was negatively associated with eGFR change over time (Stiffness × Time interaction β = –0.80, P < 0.0001), a finding that remained significant even when adjusted for biopsy status and baseline variables (Stiffness × Time interaction β = –0.46, P = 0.04). Conversely, the clinical models including “stiffness” showed significantly better fit (P = 0.04) compared with the baseline clinical models without “stiffness.”

Conclusions.

MRE-derived renal stiffness provides important prognostic information regarding renal function loss for patients with allograft dysfunction, over and above what is provided by current clinical variables.

Increased Risk of Advanced Colonic Adenomas and Timing of Surveillance Colonoscopy Following Solid Organ Transplantation

BACKGROUND

Detection and removal of colonic adenomatous polyps (CAP) decreases colorectal cancer (CRC) development, particularly with more or larger polyps or polyps with advanced villous/dysplastic histology. Immunosuppression following solid organ transplantation (SOT) may accelerate CAP development and progression compared to average-risk population but the benefit of earlier colonoscopic surveillance is unclear.

AIMS

Study the impact of maintenance immunosuppression post-SOT on developmental timing, multiplicity and pathological features of CAP, by measuring incidence of advanced CAP (villous histology, size ≥ 10 mm, ≥ 3 polyps, presence of dysplasia) post-SOT and the incidence of newly diagnosed CRC compared to average-risk age-matched population.

METHODS

Single-center retrospective cohort study of SOT recipients.

RESULTS

295 SOT recipients were included and were compared with 291 age-matched average-risk controls. The mean interval between screening and surveillance colonoscopies between SOT and control groups was 6.3 years vs 5.9 years (p = 0.13). Post-SOT maintenance immunosuppression mean duration averaged 59.9 months at surveillance colonoscopy. On surveillance examinations, SOT recipients exhibited more advanced (≥ 10 mm) adenomas compared to matched controls (9.2% vs. 3.8%, p = 0.034; adjusted OR 2.38; 95% CI 1.07-5.30).

CONCLUSION

SOT recipients appear at higher risk for developing advanced CAP, suggesting that earlier surveillance should be considered.

Transplant Onconephrology in Patients With Kidney Transplants

Cancer is a leading cause of death in patients with kidney transplantation. Patients with kidney transplants are 10- to 200-times more likely to develop cancers after transplant than the general population, depending on the cancer type. Recent advances in cancer therapies have dramatically improved survival outcomes; however, patients with kidney transplants face unique challenges of immunosuppression management, cancer screening, and recurrence of cancer after transplant. Patients with a history of cancer tend to be excluded from transplant candidacy or are required to have long cancer-free wait time before wait-listing. The strategy of pretransplant wait time management may need to be revisited as cancer therapies improve, which is most applicable to patients with a history of multiple myeloma. In this review, we discuss several important topics in transplant onconephrology: the current recommendations for pretransplant wait times for transplant candidates with cancer histories, cancer screening post-transplant, post-transplant lymphoproliferative disorder, strategies for transplant patients with a history of multiple myeloma, and novel therapies for patients with post-transplant malignancies. With emerging novel cancer treatments, it is critical to have multidisciplinary discussions involving patients, caregivers, transplant nephrologists, and oncologists to achieve patient-oriented goals.

Skin cancer in immunosuppressed patients

ABSTRACT

The number of people living with chronic immunosuppression is increasing in the United States. Patients with HIV, those who have had bone marrow or solid organ transplants, and patients taking biologics for autoimmune diseases are at increased risk for skin cancer. Skin cancer in these patients is more aggressive and more likely to metastasize and cause death. Medications and individual risk factors such as sex, age, and ethnicity are independent risk factors for the development of skin cancer. Routine screening and aggressive treatment of actinic keratoses and nonmelanoma skin cancers can reduce patients' skin cancer burden and improve patient outcomes.

Cancer Screening in Solid Organ Transplant Recipients: A Focus on Screening Liver, Lung, and Kidney Recipients for Cancers Related to the Transplanted Organ

Over the last few decades, the life expectancy of solid organ transplant recipients (SOTRs) has improved significantly. With SOTRs living longer, more recipients are dying from cancer. There is a reported 2- to 3-fold increased risk of cancer-specific mortality in SOTRs compared with the general population. Cancer in an SOTR can be de novo, recurrent, or donor-derived. Cancer screening in this population is crucial, as early detection and treatment may improve outcomes. In the absence of randomized controlled trials dedicated to SOTRs, clinicians rely on clinical practice guidelines from regional and national transplant societies; however, these may vary considerably across jurisdictions and transplanted organ. At present, no widely accepted consensus exists for cancer screening protocols in SOTRs, particularly with regard to screening for malignancy related to transplanted organ. Some SOTRs may be at higher risk of malignancies within the allograft. This is particularly the case in lung and liver recipients, though less common in kidney recipients who are at increased risk of developing renal cell cancer in their native kidneys. This increased risk has not been uniformly incorporated into screening recommendations for SOTRs. In this review, we summarize the cancer screening recommendations for SOTRs from various transplant organizations based on transplanted organ. This review also discusses the complexity and controversies surrounding screening of cancer in the allograft and future avenues to improve cancer detection in this context. More studies specific to SOTRs are required to form generalizable and evidence-based cancer screening guidelines, particularly with respect to cancer screening in the allograft.

Urological Cancers and Kidney Transplantation: a Literature Review

PURPOSE OF REVIEW

The aim of this review is to provide an overview of epidemiology, risk factors, and treatment of urological malignancies in renal transplant recipients (RTR).

RECENT FINDINGS

Although optimal immunosuppressive therapy and cancer management in these patients remain controversial, adherence to general guidelines is recommended. Kidney transplantation is recognized as the standard of care for the treatment of end-stage renal disease (ESRD) as it offers prolonged survival and better quality of life. In the last decades, survival of RTRs has increased as a result of improved immunosuppressive therapy; nonetheless, the risk of developing cancer is higher among RTRs compared to the general population. Urological malignancies are the second most common after hematological cancer and often have more aggressive behavior and poor prognosis.

Immunosuppression in liver and intestinal transplantation

Immunosuppression handling plays a key role in the early and long-term results of transplantation. The development of multiple immunosuppressive drugs led to numerous clincial trials searching to reach the ideal regimen. Due to heterogeneity of the studied patient cohorts and flaws in many, even randomized controlled, study designs, the answer still stands out. Nowadays triple-drug immunosuppression containing a calcineurin inhibitor (preferentially tacrolimus), an antimetabolite (using mycophenolate moffettil or Azathioprine) and short-term steroids with or without induction therapy (using anti-IL2 receptor blocker or anti-lymphocytic serum) is the preferred option in both liver and intestinal transplantation. This chapter aims, based on a critical review of the definitions of rejection, corticoresistant rejection and standard immunosuppression to give some reflections on how to reach an optimal immunosuppressive status and to conduct trials allowing to draw solid conclusions. Endpoints of future trials should not anymore focus on biopsy proven, acute and chronic, rejection but also on graft and patient survival. Correlation between early- and long-term biologic, immunologic and histopathologic findings will be fundamental to reach in much more patients the status of operational tolerance.

Breathlessness and Respiratory Disability After Kidney Transplantation

BACKGROUND

Dyspnea is a common symptom in patients with end-stage kidney disease being treated with dialysis. This study aimed to ascertain the level of respiratory disability in patients after kidney transplantation through assessing a cohort of kidney allograft recipients for respiratory compromise and thereby identifying a potential target for therapeutic intervention.

METHODS

Kidney transplant recipients who were under active observation in a single tertiary referral center were invited to take part in this prevalence study at the time of clinic follow-up. All patients agreed to take part in the study, which involved completing a Medical Research Council (MRC) dyspnea scale, completing the St George's Respiratory Questionnaire, and performing basic spirometry. An MRC score of ≥2 and/or a forced expiratory volume in 1 second <90% predicted prompted formal clinical assessment by a respiratory physician.

RESULTS

This study enrolled 103 patients; 35% of all patients reported breathlessness, and 56% of all patients warranted formal respiratory medicine review. After completion of their investigations, 33 patients were found to have an underlying condition accounting for their symptoms.

CONCLUSION

Our study highlights the issues of respiratory disability and breathlessness in patients who have undergone kidney transplantation. Although extensive cardiologic evaluation is performed routinely and can rule out many causes of dyspnea, respiratory assessment is not a preoperative prerequisite. This study could suggest that a formal pulmonological evaluation and basic spirometry should be part of the pretransplant evaluation of the kidney transplant recipient.

A new lateral flow assay to detect sIL-2R during T-cell mediated rejection after kidney transplantation

Kidney is the most frequently transplanted among all solid organs worldwide. Kidney transplant recipients (KTRs) undergo regular follow-up examinations for the early detection of acute rejections. The gold standard for proving a T-cell mediated rejection (TCMR) is a biopsy of the renal graft often occurring as indication biopsy, in parallel to an increased serum creatinine that may indicate deterioration of renal transplant function. The goal of the current work was to establish a lateral flow assay (LFA) for diagnosing acute TCMR to avoid harmful, invasive biopsies. Soluble interleukin-2 (IL-2) receptor (sIl-2R) is a potential biomarker representing the α-subunit of the IL-2 receptor produced by activated T-cells, e.g., after allogen contact. To explore the diagnostic potential of sIL-2R as a biomarker for TCMR and borderline TCMR, plasma and urine samples were collected from three independent KTR cohorts with various distinct histopathological diagnostic findings according to BANFF (containing 112 rsp. 71 rsp. 61 KTRs). Samples were analyzed by a Luminex-based multiplex technique and cut off-ranges were determined. An LFA was established with two specific sIL-2R-antibodies immobilized on a nitrocellulose membrane. A significant association between TCMR, borderline TCMR and sIL-2R in plasma and between TCMR and sIL-2R in urine of KTRs was confirmed using the Mann-Whitney U test. The LFA was tested with sIL-2R-spiked buffer samples establishing a detection limit of 25 pM. The performance of the new LFA was confirmed by analyzing urine samples of the 2^nd and 3^rd patient cohort with 35 KTRs with biopsy proven TCMRs, 3 KTRs diagnosed with borderline TCMR, 1 mixed AMR/TCMR rsp. AMR/borderline TCMR and 13 control patients with a rejection-free kidney graft proven by protocol biopsies. The new point-of-care assay showed a specificity of 84.6% and sensitivity of 87.5%, and a superior estimated glomerular filtration rate (eGFR) at the time point of biopsy (specificity 30.8%, sensitivity 85%).

Prostate Cancer Characteristics in Renal Transplant Recipients: A 25-Year Experience From a Single Centre

Objectives: The incidence of prostate cancer in renal transplant recipients (RTRs) is increasing, but few data are available in the literature. In this study, we reviewed the 25-year experience in the management of prostate cancer after kidney transplantation at the Florence Transplant Centre.

Methods: We retrospectively reviewed the data from 617 RTR male patients who underwent renal transplantation at our institute between July 1996 and September 2016. Data regarding demographics, renal transplantation, prostate cancer and immunosuppressive treatment were analyzed. The probability of death was estimated by using the Kaplan-Meier method and differences between patients' groups were assessed by the log-rank test.

Results: From July 1991 to September 2016, 617 kidney transplantations of male patients were performed at our institute. Among these, 20 patients were subsequently diagnosed with prostate cancer accounting for a cumulative incidence of 3.24%. After a median follow-up of 59 months, 10 patients underwent radical prostatectomy whereas 10 patients underwent primary radiotherapy. A biochemical recurrence was identified in five (25%) patients while a fatal event occurred in 11 (55%) patients. Univariate Cox regression showed that the basal value of PSA >10 ng/ml was the only significant factor negatively affecting the survival of patients.

Conclusions: Standard treatments can be proposed to RTR with satisfactory results on both post-operative and oncological outcomes. Further studies are needed to address the issue of prostate cancer screening based on PSA levels and the optimal management of prostate cancer in RTRs.

Renal transplant evaluation: multimodality imaging of post-transplant complications

With advancements in surgical techniques and immuno-suppression, renal transplantation is established as the most effective treatment option in patients with end-stage renal disease. Early detection of renal allograft complications is important for long-term graft survival. Late clinical presentation often causes diagnostic delays till the time allograft failure is advanced and irreversible. Imaging plays a key role in routine surveillance and in management of acute or chronic transplant dysfunction. Multimodality imaging approach is important with ultrasound-Doppler as the first-line imaging study in immediate, early and late post-transplant periods. Additional imaging studies are often required depending on clinical settings and initial ultrasound. Renal functional MRI is a rapidly growing field that has huge potential for early diagnosis of transplant dysfunction. Multiparametric MRI may be integrated in clinical practice as a noninvasive and comprehensive "one-stop" modality for early diagnosis and longitudinal monitoring of renal allograft dysfunctions, which is essential for guiding appropriate interventions to delay or prevent irreversible renal damage. With rapidly increasing numbers of renal transplantation along with improved patient survival, it is necessary for radiologists in all practice settings to be familiar with the normal appearances and imaging spectrum of anatomical and functional complications in a transplant kidney. Radiologist"s role as an integral part of multidisciplinary transplantation team continues to grow with increasing numbers of successful renal transplantation programs across the globe.

Post-transplant erythrocytosis after kidney transplantation: A review

Post-transplant erythrocytosis (PTE) is defined as persistently elevated hemoglobin > 17 g/dL or hematocrit levels > 51% following kidney transplantation, independent of duration. It is a relatively common complication within 8 months to 24 months post-transplantation, occurring in 8%-15% of kidney transplant recipients. Established PTE risk factors include male gender, normal hemoglobin/hematocrit pre-transplant (suggestive of robust native kidney erythropoietin production), renal artery stenosis, patients with a well-functioning graft, and dialysis before transplantation. Many factors play a role in the development of PTE, however, underlying endogenous erythropoietin secretion pre-and post-transplant is significant. Other contributory factors include the renin-angiotensin- aldosterone system, insulin-like growth factors, endogenous androgens, and local renal hypoxia. Most patients with PTE experience mild symptoms like malaise, headache, fatigue, and dizziness. While prior investigations showed an increased risk of thromboembolic events, more recent evidence tells a different story-that PTE perhaps has lessened risk of thromboembolic events or negative graft outcomes than previously thought. In the evaluation of PTE, it is important to exclude other causes of erythrocytosis including malignancy before treatment. Angiotensin converting enzyme inhibitors (ACE-I) and angiotensin receptor blockers (ARBs) are the mainstays of treatment. Increased ACE-I/ARB use has likely contributed to the falling incidence of erythrocytosis. In this review article, we summarize the current literature in the field of post-transplant erythrocytosis after kidney transplantation.

Galectin-3 and Risk of Late Graft Failure in Kidney Transplant Recipients: A 10-year Prospective Cohort Study

BACKGROUND

Galectin-3 may play a causal role in kidney inflammation and fibrosis, which may also be involved in the development of kidney graft failure. With novel galectin-3-targeted pharmacological therapies increasingly coming available, we aimed to investigate whether galectin-3 is associated with risk of late graft failure in kidney transplant recipients (KTR).

METHODS

We studied adult KTR who participated in TransplantLines Insulin Resistance and Inflammation Biobank and Cohort Study, recruited in a university setting (2001-2003). Follow-up was performed for a median of 9.5 (interquartile range, 6.2-10.2) years. Overall and stratified (Pinteraction < 0.05) multivariable-adjusted Cox proportional-hazards regression analyses were performed to study the association of galectin-3 with risk of graft failure (restart of dialysis or retransplantation).

RESULTS

Among 561 KTR (age 52 ± 12 y; 54% males), baseline median galectin-3 was 21.1 (interquartile range, 17.0-27.2) ng/mL. During follow-up, 72 KTR developed graft failure (13, 18, and 44 events over increasing tertiles of galectin-3). Independent of adjustment for donor, recipient, and transplant characteristics, galectin-3-associated with increased risk of graft failure (hazard ratios [HR] per 1 SD change, 2.12; 95% confidence interval [CI], 1.63-2.75; P < 0.001), particularly among KTR with systolic blood pressure ≥140 mmHg (HR, 2.29; 95% CI, 1.80-2.92; P < 0.001; Pinteraction = 0.01) or smoking history (HR, 2.56; 95% CI, 1.95-3.37; P < 0.001; Pinteraction = 0.03). Similarly, patients in the highest tertile of galectin-3 were consistently at increased risk of graft failure.

CONCLUSIONS

Serum galectin-3 levels are elevated in KTR, and independently associated with increased risk of late graft failure. Whether galectin-3-targeted therapies may represent novel opportunities to decrease the long-standing high burden of late graft failure in stable KTR warrants further studies.

Preoperative autologous blood donation for kidney transplant and end-stage renal disease patients: A single-center study

Although preoperative autologous blood donation (PABD) has many advantages, there has been a decrease in the performance due to a decrease in the residual risk of allogeneic blood transfusion. In allogeneic blood transfusion, anti HLA antibodies and donor-specific antibodies mediate antibody-mediated rejection, which results in graft failure. PABD for anemic patients such as those with end-stage renal disease (ESRD) and a kidney transplant is relatively contraindicated. In this study, we aimed to investigate the characteristics of patients who underwent PABD and elucidate the safety and feasibility of PABD. We performed PABD safely in ten ESRD patients and nine kidney transplant patients and retrospectively analyzed medical records of the hospital. All kidney transplant patients avoided allogeneic blood transfusion, but 4 out of 10 ESRD patients had allogeneic blood transfusion, even if their blood donation volume was larger than those of the kidney transplant patients. It depends on the type of operation; cardiovascular surgery was more common in ESRD patients, and orthopedic surgery was more common in kidney transplant patients. There was profuse bleeding in cardiovascular surgery compared to orthopedic surgery because of longer operation time of the former. Completely avoiding allogeneic blood transfusion in major surgery was rather difficult even if PABD was performed. To prevent the formation of anti- HLA antibodies, PABD would be considered for ESRD patients undergoing kidney transplantation and kidney transplant patients that are potential candidates for secondary kidney transplantation.

Impact of Pretransplant and New-Onset Diabetes After Transplantation on the Risk of Major Adverse Cardiovascular Events in Kidney Transplant Recipients: a Population-Based Cohort Study

BACKGROUND

Pretransplant diabetes and new onset diabetes after transplant (NODAT) are known risk factors for vascular events after kidney transplantation but the incidence and magnitude of the risk of major adverse cardiovascular events (MACE) and cardiac deaths remains uncertain in recent era.

METHODS

A population cohort study of kidney transplant recipients identified using data from linked administrative healthcare databases from Ontario, Canada. The incidence rates of MACE (expressed as events with 95% confidence interval (95%CI) per 1000-person-years were reported according to diabetes status of pretransplant diabetes, NODAT or no diabetes. Extended Cox regression model was used to examine the association between diabetes status, MACE and cardiac death.

RESULTS

Of 5248 recipients, 1973 (38%) had pretransplant diabetes and 799 (15%) developed NODAT with a median follow-up of 5.5 years. The incidence rates (95%CI) of MACE for recipients with pretransplant diabetes, NODAT and no diabetes between 1-3 years posttransplant were 38.1 (32.1-45.3), 12.6 (6.3-25.2) and 11.8 (9.2-15.0) per 1000-person-years, respectively. Compared to recipients with pretransplant diabetes, recipients with NODAT experienced a lower risk of MACE (adjusted hazard ratio [HR]0.59, 95%CI 0.47-0.74]), but not cardiac death [0.97(0.61-1.55)]. The rate of MACE and cardiac death was lowest in patients without diabetes.

CONCLUSIONS

Patients with pretransplant diabetes incur the greatest rate of MACE and cardiac deaths after transplantation. Having NODAT also bear high burden of vascular events compared to those without diabetes, but the magnitude of the increased rate remains lower than recipients with pretransplant diabetes.

Care of Pediatric Solid Organ Transplant Recipients: An Overview for Primary Care Providers

As the number of living pediatric solid organ transplant (SOT) recipients continues to grow, there is an increased likelihood that primary care providers (PCPs) will encounter pediatric SOT recipients in their practices. In addition, as end-stage organ failure is replaced with chronic medical conditions in transplant recipients, there is a need for a comprehensive approach to their management. PCPs can significantly enhance the care of immunosuppressed hosts by advising parents of safety considerations and avoiding adverse drug interactions. Together with subspecialty providers, PCPs are responsible for ensuring that appropriate vaccinations are given and can play an important role in the diagnosis of infections. Through early recognition of rejection and posttransplant complications, PCPs can minimize morbidity. Growth and development can be optimized through frequent assessments and timely referrals. Adherence to immunosuppressive regimens can be greatly improved through reinforcement at every encounter, particularly among adolescents. PCPs can also improve long-term outcomes by easing the transition of pediatric SOT recipients to adult providers. Although guidelines exist for the primary care management of adult SOT recipients, comprehensive guidance is lacking for pediatric providers. In this evidence-based overview, we outline the main issues affecting pediatric SOT recipients and provide guidance for PCPs regarding their management from the first encounter after the transplant to the main challenges that arise in childhood and adolescence. Overall, PCPs can and should use their expertise and serve as an additional layer of support in conjunction with the transplant center for families that are caring for a pediatric SOT recipient.

Haematological disorders following kidney transplantation

Transplantation offers cure for some haematological cancers, end-stage organ failure, but at the cost of long-term complications. Renal transplantation is the best-known kidney replacement therapy and it can prolong end-stage renal disease patient lives for decades. However, patients after renal transplantation are at a higher risk of developing different complications connected not only with surgical procedure but also with immunosuppressive treatment, chronic kidney disease progression and rejection processes. Various blood disorders can develop in post-transplant patients ranging from relatively benign anaemia through cytopenias to therapy-related myelodysplasia and acute myeloid leukaemia (AML) and post-transplant lymphoproliferative disorders followed by a rare and fatal condition of thrombotic microangiopathy and haemophagocytic syndrome. So far literature mainly focused on the post-transplant lymphoproliferative disease. In this review, a variety of haematological problems after transplantation ranging from rare disorders such as myelodysplasia and AML to relatively common conditions such as anaemia and iron deficiency are presented with up-to-date diagnosis and management.

Imaging of Renal Transplant Complications throughout the Life of the Allograft: Comprehensive Multimodality Review

The kidney is the most commonly transplanted solid organ. Advances in surgical techniques, immunosuppression regimens, surveillance imaging, and histopathologic diagnosis of rejection have allowed prolonged graft survival times. However, the demand for kidneys continues to outgrow the available supply, and there are efforts to increase use of donor kidneys with moderate- or high-risk profiles. This highlights the importance of evaluating the renal transplant patient in the context of both donor and recipient risk factors. Radiologists play an integral role within the multidisciplinary team in care of the transplant patient at every stage of the transplant process. In the immediate postoperative period, duplex US is the modality of choice for evaluating the renal allograft. It is useful for establishing a baseline examination for comparison at future surveillance imaging. In the setting of allograft dysfunction, advanced imaging techniques including MRI or contrast-enhanced US may be useful for providing a more specific diagnosis and excluding nonrejection causes of renal dysfunction. When a pathologic diagnosis is deemed necessary to guide therapy, US-guided biopsy is a relatively low-risk, safe procedure. The range of complications of renal transplantation can be organized temporally in relation to the time since surgery and/or according to disease categories, including immunologic (rejection), surgical or iatrogenic, vascular, urinary, infectious, and neoplastic complications. The unique heterotopic location of the renal allograft in the iliac fossa predisposes it to a specific set of complications. As imaging features of infection or malignancy may be nonspecific, awareness of the patient's risk profile and time since transplantation can be used to assign the probability of a certain diagnosis and thus guide more specific diagnostic workup. It is critical to understand variations in vascular anatomy, surgical technique, and independent donor and recipient risk factors to make an accurate diagnosis and initiate appropriate treatment.^©RSNA, 2019.

An update on cancer after kidney transplantation

The emergence of onconephrology in recent years highlights the importance of the interaction between kidney disease and cancer. Chronic kidney disease (CKD) and cancer are linked with each other in different ways bidirectionally: cancer can cause CKD, whereas CKD itself may be a risk factor for cancer. Kidney transplant recipients (KTRs) have a 2- to 3-fold increased cancer risk when compared with the general population. The elevated risk covers a wide range of cancers. Some are related to CKD, including cancers of the kidney, urinary tract and thyroid, whereas others are related to oncogenic viruses that include non-Hodgkin lymphoma, cervical cancer, nonmelanoma skin cancer and Kaposi's sarcoma. There is no standard protocol regarding how immunosuppressive drugs should be adjusted in patients who develop posttransplant cancers. However, any modification of immunosuppressive regimens should be balanced against the risk of allograft rejection or deterioration in kidney function. Cancer surveillance can be used as a strategy to improve the clinical outcome in KTRs. Although guidelines adopted in the general population have been used as the reference, a personalized approach based on individual cancer risk, life expectancy and concurrent comorbidities has to be adopted.

Effects of Combined Resistance Plus Aerobic Training on Body Composition, Muscle Strength, Aerobic Capacity, and Renal Function in Kidney Transplantation Subjects

Lima, PS, de Campos, AS, de Faria Neto, O, Ferreira, TCA, Amorim, CEN, Stone, WJ, Prestes, J, Garcia, AMC, and Urtado, CB. Effects of combined resistance plus aerobic training on body composition, muscle strength, aerobic capacity, and renal function in kidney transplantation subjects. J Strength Cond Res XX(X): 000-000, 2019-Immunosuppression and a sedentary lifestyle may exacerbate complications such as early graft dysfunction and muscle loss, and reduce patient survival after kidney transplantation (KT). Therefore, the purpose of this study was to evaluate changes in body composition (BC), muscular strength, aerobic, and renal function in KT subjects submitted to combined resistance plus aerobic training. Twelve KT subjects were randomly assigned into groups: (G1) 12 weeks of combined training (3 males and 4 females, 54 ± 3 years); or (G2) nonexercise control (5 females, 43 ± 18 years). The subjects were evaluated for BC (dual-energy X-ray absorptiometry), estimated V[Combining Dot Above]O2peak, right-hand maximal grip strength (RHMGS) and left-hand maximal grip strength (LHMGS), and renal function. Post-training revealed that G1 reduced body fat percentage (p = 0.046), uric acid (Δ = -0.87; p = 0.023), urea (Δ = -9.43; p = 0.032), and creatinine (Δ = -0.15; p = 0.045), increased fat-free mass, estimated V[Combining Dot Above]O2peak, RHMGS, LHMGS (p < 0.05), and estimated glomerular filtration rate (eGFR) (Δ = 11.64; p = 0.017). G2 increased urea (Δ = 8.20; p = 0.017), creatinine (Δ = 0.37; p = 0.028), and decreased eGFR (Δ = -16.10; p = 0.038). After 12 weeks, urea (Δ = 24.94; p = 0.013), uric acid (Δ = 1.64; p = 0.044), and creatinine (Δ = 0.9; p = 0.011) were lower, whereas eGFR (Δ = 36.51; p = 0.009) was higher in G1. These data indicate that combined training instigates positive changes in BC, muscular strength, aerobic capacity, and renal function after KT.

Is there evidence for efficacy of human papillomavirus vaccination in solid organ transplant recipients?

Human papillomavirus (HPV) infection is one of the most common sexually transmitted infections worldwide and is associated with precancerous lesions and cancers of the cervix, vulva, vagina, penis, anus, tonsils and base of the tongue. Several studies show an increased risk of HPV-associated cancers in solid organ transplant recipients (SOTR). The aims of this review are to investigate the evidence of efficacy for the HPV vaccination in transplant recipients and to discuss the known national guidelines. A systematic literature search has been conducted to identify studies where SOTR received the HPV vaccination to evaluate the efficacy of the HPV vaccine on this population. The primary outcome was antibody response against the HPV genotypes included in the vaccines and the secondary outcome was national guidelines recommending HPV vaccination of SOTR. Three cohort studies evaluated immunogenicity. Two studies found suboptimal effect of the HPV vaccine, while an early terminated study detected 100% seropositivity. We have identified four national guidelines in the following countries; United States of America, Canada, Australia and Ireland, along with a recommendation from the World Health Organization (WHO).

The results from the three studies were inconclusive due to the small sample sizes and the diverging results. Recommendations of HPV vaccination of SOTR is based on the knowledge about safety and efficiency in the general population and the safety of other inactivated (not live) vaccines in SOTR. Theoretically, the nonavalent vaccine should be recommended as the first choice in SOTR without age- or sex restrictions.

HDL Cholesterol Efflux Predicts Incident New-Onset Diabetes After Transplantation (NODAT) in Renal Transplant Recipients Independent of HDL Cholesterol Levels

In renal transplant recipients (RTRs), new-onset diabetes after transplantation (NODAT) is a frequent and serious complication limiting survival of graft and patient. However, the underlying pathophysiology remains incompletely understood. In vitro and in preclinical models, HDL can preserve β-cell function, largely by mediating cholesterol efflux, but this concept has not been evaluated in humans. This study investigated whether baseline cholesterol efflux capacity (CEC) in RTRs is associated with incident NODAT during follow-up. This prospective longitudinal study included 405 diabetes-free RTRs with a functioning graft for >1 year. During a median (interquartile range) follow-up of 9.6 (6.6-10.2) years, 57 patients (14.1%) developed NODAT. HDL CEC was quantified using incubation of human macrophage foam cells with apolipoprotein B-depleted plasma. Baseline CEC was significantly lower in patients developing NODAT during follow-up (median 6.84% [interquartile range 5.84-7.50%]) compared with the NODAT-free group (7.44% [6.46-8.60%]; P = 0.001). Kaplan-Meier analysis showed a lower risk for incident NODAT with increasing sex-stratified tertiles of HDL efflux capacity (P = 0.004). Linear regression analysis indicated that CEC is independently associated with incident NODAT (P = 0.04). In Cox regression analyses, CEC was significantly associated with NODAT (hazard ratio 0.53 [95% CI 0.38-0.76]; P < 0.001), independent of HDL cholesterol levels (P = 0.015), adiposity (P = 0.018), immunosuppressive medication (P = 0.001), and kidney function (P = 0.01). Addition of CEC significantly improved the predictive power of the Framingham Diabetes Risk Score (P = 0.004). This study establishes HDL CEC as a strong predictor of NODAT in RTRs, independent of several other recognized risk factors.

Evaluation of the Renal Transplant Recipient in the Emergency Department

Renal transplants are becoming more and more frequent in the United States and worldwide. Studies demonstrate that these patients inevitably end up visiting an emergency department. In addition to typical medical and surgical problems encountered in the general population, this group of patients has unique problems arising from their immunocompromised state and also due to side effects of the medications required. This article discusses these risks and management decisions that the emergency department physician should be aware of in order to prevent adverse outcomes for the patient and transplanted kidney.

Circulating Advanced Glycation Endproducts and Long-Term Risk of Cardiovascular Mortality in Kidney Transplant Recipients

BACKGROUND AND OBJECTIVES

In kidney transplant recipients, elevated circulating advanced glycation endproducts (AGEs) are the result of increased formation and decreased kidney clearance. AGEs trigger several intracellular mechanisms that ultimately yield excess cardiovascular disease. We hypothesized that, in stable kidney transplant recipients, circulating AGEs are associated with long-term risk of cardiovascular mortality, and that such a relationship is mediated by inflammatory, oxidative stress, and endothelial dysfunction biomarkers.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Prospective cohort study of stable kidney transplant recipients recruited between 2001 and 2003 in a university setting. We performed multivariable-adjusted Cox regression analyses to assess the association of AGEs (i.e., N^ε -[Carboxymethyl]lysine (CML) and N^ε -[Carboxyethyl]lysine (CEL), measured by tandem mass spectrometry) with cardiovascular mortality. Mediation analyses were performed according to Preacher and Hayes's procedure.

RESULTS

We included 555 kidney transplant recipients (age 51±12 years, 56% men). During a median follow-up of 6.9 years, 122 kidney transplant recipients died (52% deaths were due to cardiovascular causes). CML and CEL concentrations were directly associated with cardiovascular mortality (respectively, hazard ratio, 1.55; 95% confidence interval, 1.24 to 1.95; P<0.001; and hazard ratio, 1.53; 95% confidence interval 1.18 to 1.98; P=0.002), independent of age, diabetes, smoking status, body mass index, eGFR and proteinuria. Further adjustments, including cardiovascular history, did not materially change these findings. In mediation analyses, free thiol groups and soluble vascular cell adhesion molecule-1 consistently explained approximately 35% of the association of CML and CEL with cardiovascular mortality.

CONCLUSIONS

In stable kidney transplant recipients, circulating levels of AGEs are independently associated with long-term risk of cardiovascular mortality.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2019_09_17_CJN00540119.mp3.

Incidence and Risk Factors of Keratinocyte Carcinoma After First Solid Organ Transplant in Ontario, Canada

Importance

Keratinocyte carcinoma (KC), also known as nonmelanoma skin cancer, is the most common malignancy after solid organ transplant. Epidemiologic data on posttransplant KC in North America are limited by a lack of KC capture in cancer and transplant registries.

Objective

To estimate the incidence and identify risk factors for posttransplant KC.

Design, Setting, and Participants

This population-based inception cohort study in Ontario, Canada, used linked administrative databases and a health insurance claims-based algorithm. Participants were adult recipients of a first kidney, liver, heart, or lung transplant from January 1, 1994, to December 31, 2012. The cohort (n = 10 198) was followed up to December 31, 2013. Data were analyzed from May 31, 2016, to April 21, 2017.

Exposures

Solid organ transplant with functioning graft.

Main Outcomes and Measures

Age- and sex-adjusted standardized incidence ratio for KC in the transplant cohort was compared with that in the general population. Cumulative incidence of posttransplant KC was estimated using cumulative incidence functions, accounting for the competing risks of death or kidney graft loss. The association between KC and patient-, transplant-, and health services-related factors was evaluated with a multivariable cause-specific hazards model.

Results

A total of 10 198 transplant recipients were included in the study. The median (interquartile range [IQR]) age at transplant was 51 (41-59) years, with most recipients being male (6608 [64.8%]) and white (5964 [58.5%]). Posttransplant KC was diagnosed in 1690 patients (16.6%) after a median (IQR) of 3.96 (1.94-7.09) years, with an incidence rate of 2.63 per 100 patient-years (95% CI, 2.51-2.76). The rate of KC was significantly higher after transplant compared with the general population (standardized incidence ratio, 6.61; 95% CI, 6.31-6.93). The highest 10-year cumulative incidence was in the subsets of patients with a history of pretransplant skin cancer (66.5%), older than 50 years at transplant (27.5% for 51-65 years; 40.5% for >65 years), and of the white race (24.1%). The strongest independent risk factors for KC included older age at transplant (adjusted hazard ratio [aHR], 9.27; 95% CI, 7.08-12.14 for >65 years vs 18-35 years), white vs black race (aHR, 8.50; 95% CI, 4.03-17.91), pretransplant invasive skin cancer (aHR, 4.30; 95% CI, 3.72-4.98), and posttransplant precancerous skin lesions (aHR, 4.32; 95% CI, 3.77-4.95).

Conclusions and Relevance

The incidence of KC appeared to be substantially increased after transplant, particularly in patients who were older at transplant, were white, and had a history of cancerous or precancerous skin tumors; intensified skin cancer screening, education, and early use of chemopreventive interventions may be warranted for these high-risk patient subsets.

The interaction between post-transplant anemia and allograft function in kidney transplantation: The Japan Academic Consortium of Kidney Transplantation-II study

BACKGROUND

The interaction between post-transplant anemia (PTA) and allograft function in kidney transplantation has not been evaluated directly. PTA, defined by WHO/AST criteria, was investigated in 1307 adult kidney transplant recipients between 2000 and 2015 (median follow-up, 7 years).

METHODS

We investigated the impact of hemoglobin (Hb) on graft failure (non-censored for death) and their interactions, time-dependent Cox model, and subgroup analysis were used.

RESULTS

PTA prevalence was 43.6% at 7 years and varied according to allograft function, recipient sex, and follow-up period. Decreased Hb considering the time-varying effect was associated with an increased risk of graft failure (hazard ratio = 1.83, 95% CI 1.66-2.02, P < 0.001). In subgroup analysis, allograft function (post-transplant time-averaged estimated glomerular filtration rate and cut point: 45 mL/min/1.73 m²) had significant interaction (P = 0.032). The 7-year graft failure rate in recipients with PTA and high eGFR was 7.7% (HR 1.52, 95% CI 1.25-1.84), whereas in those with PTA and low eGFR was 19.9% (HR 2.00, 95% CI 1.74-2.31).

CONCLUSIONS

The unfavorable impact of PTA was significantly enhanced by low allograft function. PTA is likely to be associated with graft failure due to interaction with allograft function. Therefore, we should consider both Hb level and allograft function while determining the treatment strategy.

Detection and Characterization of Atypical Renal Cysts and Solid Renal Masses in Kidney Transplant Patients by Use of Dual-Energy CT Iodine Maps

OBJECTIVE. The purpose of this study was to evaluate whether dual-energy CT follow-up of kidney transplant recipients performed with only two contrast-enhanced phases and reconstructed material maps has the same diagnostic efficiency as triphasic conventional CT in detection and characterization of atypical renal cysts and renal masses. MATERIALS AND METHODS. In a retrospective study, 175 renal transplant patients underwent dual-energy CT as part of their follow-up (monoenergetic unenhanced, late contrast-enhanced, and tubular contrast-enhanced dual-energy phases). An unenhanced virtual series and material separation maps were reconstructed. ROIs were marked on theses lesions, the bladder, and the psoas muscle. Material suppressed iodine was used to record attenuation measurements on the unenhanced and virtual unenhanced series in the tubular and late phases, and material concentration measurements were obtained on the iodine density images. The delivered doses for each series were registered. RESULTS. One hundred one renal lesions (spontaneous attenuation > 20 HU, size > 10 mm) were detected. An iodine concentration threshold greater than 1500 μg/mL was associated with excellent diagnostic performance (sensitivity, 100%; specificity, 92.55%; positive predictive value, 50%; negative predictive value, 100%) for detection of suspect lesions (enhancement > 20 HU). The two lesions with an iodine concentration greater than 5000 μg/mL corresponded to the only two histologically proven cancers. CONCLUSION. Iodine concentration maps obtained with dual-energy CT perform as well as enhanced images obtained at conventional CT in the detection and characterization of tissue and atypical cystic renal lesions in kidney transplant recipients. Use of this method could reduce radiation dose, especially by avoiding the unenhanced series.

Incidence and Mortality of Renal Cell Carcinoma after Kidney Transplantation: A Meta-Analysis

Background: The incidence and mortality of renal cell carcinoma (RCC) after kidney transplantation (KTx) remain unclear. This study’s aims were (1) to investigate the pooled incidence/incidence trends, and (2) to assess the mortality/mortality trends in KTx patients with RCC. Methods: A literature search was conducted using the MEDLINE, EMBASE and Cochrane databases from inception through October 2018. Studies that reported the incidence or mortality of RCC among kidney transplant recipients were included. The pooled incidence and 95% CI were calculated using a random-effect model. The protocol for this meta-analysis is registered with PROSPERO; no. CRD42018108994. Results: A total of 22 observational studies with a total of 320,190 KTx patients were enrolled. Overall, the pooled estimated incidence of RCC after KTx was 0.7% (95% CI: 0.5–0.8%, I² = 93%). While the pooled estimated incidence of de novo RCC in the native kidney was 0.7% (95% CI: 0.6–0.9%, I² = 88%), the pooled estimated incidence of RCC in the allograft kidney was 0.2% (95% CI: 0.1–0.4%, I² = 64%). The pooled estimated mortality rate in KTx recipients with RCC was 15.0% (95% CI: 7.4–28.1%, I² = 80%) at a mean follow-up time of 42 months after RCC diagnosis. While meta-regression analysis showed a significant negative correlation between year of study and incidence of de novo RCC post-KTx (slopes = −0.05, p = 0.01), there were no significant correlations between the year of study and mortality of patients with RCC (p = 0.50). Egger’s regression asymmetry test was performed and showed no publication bias in all analyses. Conclusions: The overall estimated incidence of RCC after KTX was 0.7%. Although there has been a potential decrease in the incidence of RCC post-KTx, mortality in KTx patients with RCC has not decreased over time.