US Kidney Research Articles

External validation of the US and UK kidney donor risk indices for deceased donor kidney transplant survival in the Australian and New Zealand population.

The US Kidney Donor Risk Index (KDRI) and the UK KDRI were developed to estimate the risk of graft failure following kidney transplantation. Neither score has been validated in the Australian and New Zealand (ANZ) population. Using data from the Australia and New Zealand Organ Donor (ANZOD) and Dialysis and Transplant (ANZDATA) Registries, we included all adult deceased donor kidney-only transplants performed in ANZ from 2005 to 2016 (n = 6405). The KDRI was calculated using both the US donor-only and UK formulae. Three Cox models were constructed (Model 1: KDRI only; Model 2: Model 1 + transplant characteristics; Model 3: Model 2 + recipient characteristics) and compared using Harrell's C-statistics for the outcomes of death-censored graft survival and overall graft survival. Both scores were strongly associated with death-censored and overall graft survival (P < 0.0001 in all models). In the KDRI-only models, discrimination of death-censored graft survival was moderately good with C-statistics of 0.63 and 0.59 for the US and UK scores, respectively. Adjusting for transplant characteristics resulted in marginal improvements of the US KDRI to 0.65 and the UK KDRI to 0.63. The addition of recipient characteristics again resulted in marginal improvements of the US KDRI to 0.70 and the UK KDRI to 0.68. Similar trends were seen for the discrimination of overall graft survival. The US and UK KDRI scores were moderately good at discriminating death-censored and overall graft survival in the ANZ population, with the US score performing slightly better in all models.

Recent History of Serious Fall Injuries and Posttransplant Outcomes Among US Kidney Transplant Recipients.

Serious fall injuries are associated with poor outcomes among dialysis patients, but whether these associations hold in patients with a history of serious fall injury before kidney transplantation is unknown. In national administrative data, 22 474 US adults receiving a first kidney transplant in 2011-2014 with at least 1 year of follow-up before transplant were identified. Serious fall injuries in the year before transplant were identified using diagnostic codes for falls and simultaneous fractures, dislocations, or head trauma in inpatient or outpatient claims. We used multivariable Cox proportional hazards models to estimate associations of incident posttransplant outcomes with serious fall injury in the year before transplant. A total of 620 (2.8%) recipients had serious fall injuries before transplant and were more likely to be white, female, and have more comorbid conditions than those without a fall injury. Although posttransplant recipient survival did not differ by recent serious fall injuries (hazard ratio [HR], 1.03; 95% confidence interval [CI], 0.78-1.36), these injuries were associated with 33% higher rates of graft failure (HR, 1.33; 95% CI, 1.03-1.72). Patients with serious fall injuries spent 12.1% of posttransplant follow-up hospitalized, a 3.3-fold higher rate than those without a fall, and had nearly 2-fold higher rates of skilled nursing facility utilization (HR, 1.98; 95% CI, 1.52-2.57). Serious fall injuries are independently associated with significantly greater resource requirements and lower graft survival. Further study is needed to delineate the relationship between falls and adverse outcomes in transplant and reduce the incidence and deleterious effects of these events.

Optimal GLCM combined FCM segmentation algorithm for detection of kidney cysts and tumor

In this document, we employed an efficient Optimal GLCM attribute related FCM segmentation algorithm which is used to categorize the kidney cysts and tumor from the ultrasound kidney images. The FCM is exploiting some appropriate attributes of GLCM texture feature extractor and optimally attach the cluster centroids of FCM by the help of Whale optimization algorithm. The proposed approach is executed in the working platform of Matlab. The findings demonstrate that the proposed model have better performance in recognizing the detection of kidney cysts and tumor in patients by examining US kidney images. Also, we have shown the comparison of our proposed method FB-FCM-WOA with the existing methodologies like FB-FCM, FB-K-means, IB-FCM and IB-K-means. Hence, we would suggest that our proposed method is much better for detecting kidney cysts and tumor.

Multi-instance Deep Learning with Graph Convolutional Neural Networks for Diagnosis of Kidney Diseases Using Ultrasound Imaging.

Ultrasound imaging (US) is commonly used in nephrology for diagnostic studies of the kidneys and lower urinary tract. However, it remains challenging to automate the disease diagnosis based on clinical 2D US images since they provide partial anatomic information of the kidney and the 2D images of the same kidney may have heterogeneous appearance. To overcome this challenge, we develop a novel multi-instance deep learning method to build a robust classifier by treating multiple 2D US images of each individual subject as multiple instances of one bag. Particularly, we adopt convolutional neural networks (CNNs) to learn instance-level features from 2D US kidney images and graph convolutional networks (GCNs) to further optimize the instance-level features by exploring potential correlation among instances of the same bag. We also adopt a gated attention-based MIL pooling to learn bag-level features using full-connected neural networks (FCNs). Finally, we integrate both instance-level and bag-level supervision to further improve the bag-level classification accuracy. Ablation studies and comparison results have demonstrated that our method could accurately diagnose kidney diseases using ultrasound imaging, with better performance than alternative state-of-the-art multi-instance deep learning methods.

Development of a Calculated Panel Reactive Antibody Web Service with Local Frequencies for Platelet Transfusion Refractoriness Risk Stratification

Background: Calculated panel reactive antibody (cPRA) scoring is used to assess whether platelet refractoriness is mediated by human leukocyte antigen (HLA) antibodies in the recipient. cPRA testing uses a national sample of US kidney donors to estimate the population frequency of HLA antigens, which may be different than HLA frequencies within local platelet inventories. We aimed to determine the impact on patient cPRA scores of using HLA frequencies derived from typing local platelet donations rather than national HLA frequencies. Methods: We built an open-source web service to calculate cPRA scores based on national frequencies or custom-derived frequencies. We calculated cPRA scores for every hematopoietic stem cell transplantation (HSCT) patient at our institution based on the United Network for Organ Sharing (UNOS) frequencies and local frequencies. We compared frequencies and correlations between the calculators, segmented by gender. Finally, we put all scores into three buckets (mild, moderate, and high sensitizations) and looked at intergroup movement. Results: 2531 patients that underwent HSCT at our institution had at least 1 antibody and were included in the analysis. Overall, the difference in medians between each group's UNOS cPRA and local cPRA was statistically significant, but highly correlated (UNOS vs. local total: 0.249 and 0.243, ρ = 0.994; UNOS vs. local female: 0.474 and 0.463, ρ = 0.987, UNOS vs. local male: 0.165 and 0.141, ρ = 0.996; P < 0.001 for all comparisons). The median difference between UNOS and cPRA scores for all patients was low (male: 0.014, interquartile range [IQR]: 0.004–0.029; female: 0.0013, IQR: 0.003–0.028). Placement of patients into three groups revealed little intergroup movement, with 2.96% (75/2531) of patients differentially classified. Conclusions: cPRA scores using local frequencies were modestly but significantly different than those obtained using national HLA frequencies. We released our software as open source, so other groups can calculate cPRA scores from national or custom-derived frequencies. Further investigation is needed to determine whether a local-HLA frequency approach can improve outcomes in patients who are immune-refractory to platelets.

Coexistence xanthogranulomatous pyelonephritis with renal replacement lipomatosis. Computed tomography. Сlinical case

Xanthogranulomatous pyelonephritis is a relatively rare form of chronic pyelonephritis. It is characterized by combination of destructive and proliferative processes with proliferation in the kidney of granulomatous tissue with a large number of lipid-containing macrophages, which are called xanthomous or "foamy" cells. Replacement kidney lipomatosis is also a rare disease that is characterized by proliferation of adipose tissue of the kidney sinus and perirenal adipose tissue with pronounced atrophy of the renal parenchyma. This is the result of renal atrophy, chronic inflammation, nephrolithiasis or long-term current hydronephrosis with the proliferation of adipose tissue in the renal sinus and paranephric fiber. The article presents a case of combining the above-mentioned pathological processes in a patient of the 93-ies. According to clinical manifestations and examination data, xanthogranulomatous pyelonephritis can occur under the guise of pionephrosis, carbuncle, abscess. Deservedly this disease is called "great imitator", because today there are no clear diagnostic criteria, and the diagnosis is established, as a rule, in the postoperative period.

Procurement Biopsy Findings Versus Kidney Donor Risk Index for Predicting Renal Allograft Survival.

Efforts to maximize transplantation by matching organ quality to recipient longevity require reliable tools. The US kidney allocation system uses the Kidney Donor Risk Index (KDRI) for this purpose, and many centers additionally rely on donor biopsies. The Leuven score combines donor age with procurement histology (glomerulosclerosis and interstitial fibrosis/tubular atrophy) to predict allograft survival. We compared KDRI with Leuven scores for associations with kidney discard, delayed graft function, and allograft function and survival. We used Cox, modified Poisson, and linear regression to calculate risks based on KDRI and (separately) Leuven scores, adjusting for important transplant and recipient variables. From 890 donors, 1729 kidneys were procured and biopsied. Five hundred eighty-five (34%) kidneys were discarded. Median donor age was 53 years (interquartile range [IQR], 44-61 years). Median KDRI and Leuven scores were 1.56 (IQR, 1.28-1.90) and 59 (IQR, 49-69). Relative risk for discard was 1.21 (95% confidence interval [CI], 1.17-1.24) per 0.2-unit increase in KDRI and 1.38 (1.31-1.46) per 10-unit increase in Leuven score. Adjusted relative risks for delayed graft function were 0.98 (95% CI, 0.94-1.02) and 0.94 (95% CI, 0.90-0.99), adjusted hazard ratios for graft failure were 1.10 (95% CI, 1.04-1.16) and 1.11 (95% CI, 1.02-1.21), and adjusted linear regression coefficients for 3-year estimated glomerular filtration rate were -3.88 (-4.63 to -3.13) and -5.18 (-6.19 to -4.18). In kidneys clinically selected for procurement biopsy, the Leuven score was more strongly associated with discard but performed similarly to KDRI for predicting transplant outcomes, suggesting the need to reevaluate current procurement biopsy practices. Given modest associations for both tools; however, neither KDRI nor the Leuven score should be used in isolation for individual organ acceptance decisions.

Renal cell carcinoma risk associated with lower intake of micronutrients.

Kidney cancer incidence in African Americans (AA) is higher than among European Americans (EA); reasons for this disparity are not fully known. Dietary micronutrients may have a protective effect on renal cell carcinoma (RCC) development by inhibiting oxidative DNA damage and tumor growth. We evaluated whether any micronutrient associations differed by race in the US Kidney Cancer Study. 1142 EA and AA RCC cases and 1154 frequency‐matched controls were enrolled in a population‐based case‐control study between 2002 and 2007. Dietary micronutrient intake was derived from an interviewer‐administered diet history questionnaire. RCC risk associated with micronutrient intake was estimated using adjusted odds ratios from logistic regression comparing lower to highest quartiles of intake and sample weighting. Inverse associations with RCC risk were observed for α‐carotene, β‐carotene, lutein zeaxanthin, lycopene, vitamin A, folate, thiamin, vitamin C, α‐tocopherol, β‐tocopherol, γ‐tocopherol, and selenium. A trend for β‐cryptoxanthin was suggested among EA but not AA or the total sample (P‐interaction = .04). Otherwise, findings did not differ by race, gender, age, or smoking status. The increase in RCC risk associated with lower micronutrient intake is similar within AA and EA populations. A diet rich in sources of micronutrients found in fruits, vegetables, and nuts may help to reduce the overall risk of RCC.

Virtual Crossmatch Permits Kidney Sharing; Avoiding Transplant into Unintended Recipients

Aim The US Kidney Allocation System successfully exposes highly sensitized patients (pts) with a cPRA of 99 or 100% to deceased donor offers through regional and national sharing. Frequently a positive physical cross match (PXM) occurs while a kidney is being transported, requiring subsequent reallocation. It was estimated that 19.2% of kidneys transported between regions are eventually transplanted (tx) into an unintended recipient(UR), most commonly due to a positive crossmatch (AJT 2017, 17:2139). Using a virtual cross match (VXM) strategy, we aimed to tx highly sensitized pts with kidneys from other regions, without reallocating to an UR. Methods We developed a VXM strategy to avoid a positive PXM. Our VXM method includes 3 integral processes: accurate identification of HLA antibodies (Ab) using right tools and scientific principles on quarterly samples, assessment of correlation between the strength of donor specific HLA Ab (DSA) and the level of T/B cell bindings by flow XM (PXM), and listing of clinically relevant unacceptable antigens that will not impact donor offers or graft survival. When a kidney is offered a VXM is performed, and likelihood of positive PXM is estimated by the HLA lab director. If there is concern due to recent transfusions or infections treated with antibiotics a PXM is done when the pt arrives for tx, but is only required in a minority of cases. Records were reviewed of all kidneys shipped from another region since Dec, 2014 to identify kidneys not used in the intended recipient from Dec, 2014 to Sept, 2017. Results 252 kidneys were shipped to our center from another region based on the negative VXM (Fig 1). Of these imported kidneys 210 (83.3%) were transplanted without a pre-tx PXM, and the remaining 42(16.7%) required a PXM on admission, most commonly necessitated by a recent blood transfusion. 109 pts with 100% cPRA had kidneys imported, and 93 (85.3%) were transplanted after VXM alone. 7 kidneys went to UR, but only 3 (1.2%) were due to a pos PXM or new DSA from recent blood transfusion. The other 4 kidneys went to UR because the intended recipient had a new medical problem upon admission. Mean creatinine at 1-year was 1.30 for pts at highest immunologic risk(cPRA 100%), and 1.31(p=NS) for all other DDRT recipients. VXM alone was used in 114(86.3%) of females, and 92(79%) of re-transplant pts. Consistent with the neg VXM, retrospective PXM performed by flow cytometry for all recipients were negative (Fig 2). Conclusions Sharing is possible, and late reallocations can be almost entirely avoided with a strategy that relies heavily on VXM, without limiting access for highly sensitized pts on the waitlist. A centralized VXM within the allocation system would reduce transplantation into unintended recipients significantly. More frequent antibody screening, especially following blood transfusions and infections would further reduce the need for a pre-tx PXM.

Evolving Trends in Racial Disparities for Peri-Operative Outcomes with the New Kidney Allocation System (KAS) Implementation.

To improve kidney transplant allocation equitability, a new Kidney Allocation System (KAS) was implemented December 4, 2014. The purpose of this study was to determine if the impact of KAS on peri-operative outcomes differed by recipient race/ethnicity. This was a time series analysis using data aggregated in monthly intervals from October 2012 through September 2015 using the University HealthSystem Consortium (UHC). This includes national data aggregated at the center level of all US kidney transplant centers that participate in the UHC (416 centers). Segmented regression with interaction terms was used to determine the impact of KAS on outcomes and differences by race/ethnicity. A total of 28,809 deceased donor kidney transplants were included with 25months of pre-KAS data and 10months of post-KAS data. After KAS implementation, the estimated transplant rate per month decreased significantly for Caucasians by 17.6 cases per month (p = 0.0001), and increased significantly for AAs by 37.8 (p = 0.0001), Hispanics by 16.3 (p = 0.0001), and other races by 8.2 cases per month (p = 0.0001). Delayed graft function, 7- and 14-day readmissions significantly increased after KAS, which did not differ by race. Hispanics saw a 7.7% decrease in ICU admissions after KAS, which differed as compared to other racial/ethnic cohorts (p = 0.0026). Costs of kidney transplantation increased significantly after KAS in all groups except Hispanics. Mortality, length of stay, in-hospital complications, and 30-day readmissions were not significantly impacted by KAS, also not differing by race/ethnicity. KAS had substantial impact on transplant rates by race/ethnicity. KAS also led to increased costs, readmissions, and delayed graft function (DGF) across all racial/ethnic groups. The impact of KAS on ICU cases solely within Hispanics requires further investigation into potential etiologies.

Complete Chain of the First Global Kidney Exchange Transplant and 3-yr Follow-up

BackgroundGlobal Kidney Exchange (GKE) offers an opportunity to expand living renal transplantation internationally to patients without financial means. These international pairs are entered into a US kidney exchange program that provides long-term financial support in an effort to identify opportunities for suitable exchanges for both these international pairs and US citizens. ObjectiveWhile the promise of GKE is significant, it has been met with ethical criticism since its inception in 2015. This paper aims to demonstrate the selection process and provide >3 yr of follow-up on the first GKE donor and recipient from the Philippines. Design, setting, and participantsThe first GKE transplant occurred with a young Filipino husband and wife who were immunologically compatible, but lacked the financial means to continue hemodialysis or undergo a kidney transplant in their home country. The pair was enrolled in the Alliance for Paired Donation matching system, several alternative kidney exchanges were identified, and the pair subsequently underwent renal transplantation and donation in the USA financed by philanthropy. The resulting nonsimultaneous extended altruistic chain provided transplantation for the Filipino husband and 11 US patients. Outcome measurements and statistical analysisThe Filipino donor and recipient were followed by transplant professionals in both the Philippines and the USA. Follow-up data were maintained as required by the Organ Procurement and Transplantation Network in the USA. Results and limitationsThe Filipino donor has normal blood pressure and renal function, and the Filipino recipient is doing well 3.5 yr after their donation and transplantation. ConclusionsWhile criticisms of GKE highlight concerns for possible exploitation of financially disadvantaged groups, these results demonstrate that these concerns did not come to fruition, and the outcome experienced by the GKE donor and recipient (and other US participants) was successful. Patient summaryThe first Filipino Global Kidney Exchange (GKE) donor-recipient pair continues to be followed by both US and Filipino transplant centers. Both are in good health, support the GKE program, and advocate for its expansion.

Center practice drives variation in choice of US kidney transplant induction therapy: a retrospective analysis of contemporary practice.

To assess factors that influence the choice of induction regimen in contemporary kidney transplantation, we examined center-identified, national transplant registry data for 166 776 US recipients (2005-2014). Bilevel hierarchical models were constructed, wherein use of each regimen was compared pairwise with use of interleukin-2 receptor blocking antibodies (IL2rAb). Overall, 82% of patients received induction, including thymoglobulin (TMG, 46%), IL2rAb (22%), alemtuzumab (ALEM, 13%), and other agents (1%). However, proportions of patients receiving induction varied widely across centers (0-100%). Recipients of living donor transplants and self-pay patients were less likely to receive induction treatment. Clinical factors associated with use of TMG or ALEM (vs. IL2rAb) included age, black race, sensitization, retransplant status, nonstandard deceased donor, and delayed graft function. However, these characteristics explained only 10-33% of observed variation. Based on intraclass correlation analysis, "center effect" explained most of the variation in TMG (58%), ALEM (66%), other (51%), and no induction (58%) use. Median odds ratios generated from case-factor adjusted models (7.66-11.19) also supported large differences in the likelihood of induction choices between centers. The wide variation in induction therapy choice across US transplant centers is not dominantly explained by differences in patient or donor characteristics; rather, it reflects center choice and practice.

HLA Population Genetics in Solid Organ Transplantation.

HLAs are fundamental to the adaptive immune response and play critical roles in the cellular and humoral response in solid organ transplantation. The genes encoding HLA proteins are the most polymorphic within the human genome, with thousands of different allelic variants known within the population. Application of the principles of population genetics to the HLA genes has resulted in the development of a numeric metric, the calculated panel-reactive antibody (CPRA) that predicts the likelihood of a positive crossmatch as a function of a transplant candidate's unacceptable HLA antigens. The CPRA is an indispensible measure of access to transplantation for sensitized candidates and is used as the official measure of sensitization for allocation of points in the US Kidney Allocation System and Eurotransplant. Here, we review HLA population genetics and detail the mathematical basis of the CPRA. An understanding of these principles by transplant clinicians will lay the foundation for continued innovation in the care of sensitized patients.

Kidney Vouchers and Inequity in Transplantation.

This article probes the voucher program from an ethical perspective. It focuses mainly on an issue of inequity. A disparity exists in US kidney transplantation. Although African-Americans suffer far higher rates of ESRD than whites, African-Americans are much less likely than whites to get a transplant (Ilori et al., 2015, 1). The article explores the voucher program in light of this disparity. It motivates the view that, at least in the short term, more whites than African-Americans are likely to take advantage of the voucher program. The program is, thus, likely to increase the gap in transplantation rates between the two groups. If this is correct, what impact does it have on the moral acceptability of the program?

Leukocyte telomere length and renal cell carcinoma survival in two studies

Background:Leukocyte telomere length (LTL) is a potential biomarker of cancer prognosis; however, evidence for renal cell carcinoma (RCC) is inconsistent.Methods:We investigated LTL and RCC-specific survival among 684 cases from the US kidney cancer study (USKC) and 241 cases from the prostate, lung, colorectal, and ovarian cancer screening trial (PLCO). Leukocyte telomere length was measured by quantitative polymerase chain reaction, and hazard ratios (HRs) and 95% confidence intervals (CIs) computed using multivariable Cox models.Results:Short LTL was associated with poorer disease-specific survival in both USKC (lowest vs highest quartile: HR: 2.3, 95% CI: 1.2–4.4; P for trend=0.02) and PLCO (HR: 2.4, 95% CI: 1.0–5.4; P=0.04). Among USKC cases, the association was strongest for stage-I RCC (HR: 5.5, 95% CI: 1.6–19.0; P=0.006).Conclusions:Our findings suggest that shorter LTL is an independent marker of poor RCC prognosis, particularly for stage-I disease.

Logistic Bayesian LASSO for genetic association analysis of data from complex sampling designs.

Detecting gene-environment interactions (GXE) with rare variants is critical in dissecting the etiology of common diseases. Interactions with rare haplotype variants (rHTV) are of particular interest. At the same time, complex sampling designs, such as stratified random sampling, are becoming increasingly popular for designing case-control studies, especially for recruiting controls. The US Kidney Cancer Study (KCS) is an example, wherein all available cases were included while the controls at each site were randomly selected from the population by frequency matching with cases based on age, sex, and race. There is currently no rHTV association method that can account for such a complex sampling design. To fill this gap, we consider logistic Bayesian LASSO (LBL), an existing rHTV approach for case-control data, and show that its model can easily accommodate the complex sampling design. We study two extensions that include stratifying variables either as main effects only or with additional modeling of their interactions with haplotypes. We conduct extensive simulation studies to compare the complex sampling methods with the original LBL methods. We find that when there is no interaction between haplotype and stratifying variables, both extensions perform well while the original LBL methods lead to inflated type I error rates. However, when such an interaction exists, it is necessary to include the interaction effect in the model to control the type I error. Finally, we analyze the KCS data and find a significant interaction between (current) smoking and a specific rHTV in the N-acetyltransferase 2 (NAT2) gene.

Impact of the New Kidney Allocation System on Perioperative Outcomes and Costs in Kidney Transplantation

In December 2014, a new kidney allocation system (KAS) was implemented nationwide with the goal of improving longevity matching, increasing access to sensitized patients, and improving racial/ethnic disparities. National cohort study of US kidney transplantation programs, analyzing hospital-level outcomes (October 2012 to June 2016) using University HealthSystem Consortium data. In-hospital outcomes and costs were analyzed for trends over time using interrupted time series analysis with segmented regression. There were 38,016 kidney transplantation procedures analyzed during the 3.8-year period. Over time, there was a mean increase of 2.7 cases/month (95% CI-0.02 to 5.4; p= 0.059), unaffected by KAS (18.9 case increase; p= 0.5601). Implementation of KAS led to significant changes in patient demographics, including a decrease in age (-2.8 years; p<0.001), increase in number of African Americans (3.8%; p < 0.001), decrease in number of Caucasians (6.0%; p < 0.001), increase in number of Hispanics (2.9%; p < 0.001), increase in congestive heart failure (1.3%; p < 0.001), and decrease in diabetes with complications (4.0%; p < 0.001). The KAS had no impact on length of stay (0.12 days; 95% CI-0.11 to 0.35), length of stay index (0.01; 95% CI-0.03 to 0.05), ICU cases, ICU length of stay, patient safety indicators, or in-hospital mortality. The KAS led to a significant increase in delayed graft function rates (5.4%; 95% CI 23.3% to 7.4%); total in-hospital costs ($2,429; 95% CI $594 to $4.263); and 7-day (2.2%), 14-day (2.6%), and 30-day (2.7%) readmission rates. Policy changes in organ allocation can have a significant impact on perioperative costs and outcomes, which can have a downstream influence on transplantation center perisurgical care processes.

Risk of Renal Cell Carcinoma Among Kidney Transplant Recipients in the United States.

Renal cell carcinoma (RCC) is a common malignancy following kidney transplantation. We describe RCC risk and examine RCC risk factors among US kidney recipients (1987-2010). The Transplant Cancer Match Study links the US transplant registry with 15 cancer registries. Standardized incidence ratios (SIRs) were used to compare RCC risk (overall and for clear cell [ccRCC] and papillary subtypes) to the general population. Associations with risk factors were assessed using Cox models. We identified 683 RCCs among 116 208 kidney recipients. RCC risk was substantially elevated compared with the general population (SIR 5.68, 95% confidence interval 5.27-6.13), especially for papillary RCC (SIR 13.3 versus 3.98 for ccRCC). Among kidney recipients, RCC risk was significantly elevated for blacks compared to whites (hazard ratio [HR] 1.50) and lower in females than males (HR 0.56). RCC risk increased with prolonged dialysis preceding transplantation (p-trend < 0.0001). Risk was variably associated for RCC subtypes with some medical conditions that were indications for transplantation: ccRCC risk was reduced with polycystic kidney disease (HR 0.54), and papillary RCC was increased with hypertensive nephrosclerosis (HR 2.02) and vascular diseases (HR 1.86). In conclusion, kidney recipients experience substantially elevated risk of RCC, especially for papillary RCC, and multiple factors contribute to these cancers.

Chronic kidney disease from screening, detection, and awareness, to prevention.

Chronic kidney disease from screening, detection, and awareness, to prevention.

Impact of preoperative ultrasonography findings on the patency rate of vascular access in Japanese hemodialysis patients.

BackgroundAlthough ultrasonography before a vascular access (VA) operation has become popular in recent years, benchmarks for the diameter or blood flow of arteries or veins are not defined in Japan. The objective of the present study is to analyze the relationship between preoperative US findings and the patency rate of VA in Japanese hemodialysis patients.Methods139 patients with end stage kidney disease were enrolled in this study. They had been given primary radiocephalic arteriovenous fistula (AVF) from February 2009 to December 2010 at the Juntendo University Hospital and were followed up over 2 years. We defined the interval from the time of AVF creation until first access thrombosis or any intervention to maintain or restore blood flow as patency time (primary patency). We examined the correlation between the 2-year primary patency rate of VA and the diameter of the radial artery (RA), brachial artery (BA), or cephalic vein at an anastomosis presumptive region by US, the blood flow of RA or BA, as measured by US, age, gender, and primary kidney diseases.ResultsThe average patency term was 448.6 ± 271.3 days, with the 1-year and 2-year patency rate as 64.0 and 51.2 %, respectively. The patency rate was significantly lower in elderly patients over the age of 75 and in patients with diabetes mellitus. US findings of 2.0 mm or less in the RA diameter also resulted in a noticeably low patency rate. A multivariate analysis indicated that those factors were risk factors for early VA failure.ConclusionsPreoperative US findings of the diameter of RA may involve the patency rate of VA, making it appears that an RA of 2.0 mm or more in diameter at an anastomosis region may be more effective for the improvement in the patency rate of VA.