Meta-analysis of Early Versus Late Ureteric Stent Removal After Kidney Transplantation

Background

Ureteral stents have been widely used in kidney transplantation to prevent postoperative ureter-related complications such as ureteral stricture, ureteral obstruction, and ureteral leakage; however, a longer indwelling ureteral stent time corresponds to a greater risk of complications such as urinary tract infections. Currently, transplantation centers have not yet reached an agreement on the time to remove ureteral stents. Several randomized controlled trials (RCTs) have evaluated the optimal removal time for ureteral stents.

Elevated Incidence of Posttransplant Erythrocytosis After Simultaneous Pancreas Kidney Transplantation

Posttransplant erythrocytosis (PTE) poses a potential risk of thrombosis in kidney transplantation. Clinical observation of our systemically drained simultaneous kidney pancreas transplant (S‐SPK) patients showed a higher incidence of PTE and need for phlebotomies. To evaluate the incidence of PTE we analyzed hematocrit (Hct) levels and frequency of phlebotomies in 94 SPK as compared to 174 living donor (LD) recipients and 53 type‐I diabetic with kidney transplant only. For study purposes we defined PTE as Hct >50% or the necessity for phlebotomies. Kaplan–Meier plots and Cox proportional hazard models were used to examine the association between the transplant type and PTE. We found an increased incidence of PTE in SPK compared to LD (p < 0.001). In the multivariate model, SPK had a 5‐fold risk for the development of PTE (AHR 5.3, 95% CI 1.8, 15.9). The incidence of therapeutic phlebotomy was 13% among SPK patients and 4% in LD kidney recipients; 19 patients altogether. A total of 64 units were phlebotomized (48‐SPK and 16‐LD). Type I diabetic patients with a kidney transplant showed a 0% incidence of PTE. We observed a greater incidence of PTE and phlebotomies in S‐SPK compared to LD with kidney only transplant recipients.     

Surgical Site Infections in the Early Posttransplant Period After Simultaneous Pancreas–Kidney Transplantation

Objective

This study evaluated the frequency of microbial isolates and their susceptibility profiles among cultures from the “surgical site” of 26 simultaneous pancreas-kidney (SPKT) recipients in the early posttransplant period.

Patients and Methods

Data on microbiologic cultures of 26 adult patients undergoing SPKT were collected prospectively from 2001 to the end of 2006. The isolation and identification of cultured micro-organisms was performed according to standard microbiological procedures and commercially available tests. Susceptibility of the strains to antibacterial agents was made by the Clinical and Laboratory Standards Institute (CLSI) guidelines.

Results

All patients were followed prospectively for the first 4 weeks after surgery yielding 168 microbial isolates from the surgical site. The most commonly isolated organisms were Gram-positive bacteria (65.5%) with domination of staphylococci (52.7%) as methicillin-resistant S aureus and methicillin-resistant coagulase-negative staphylococci. The second most common were enterococci (33.6%) with the presence of an high level aminoglycoside-resistant strains (64.9%) and vancomycin-resistant strains (2.7%). Gram-negative bacteria comprised 19% of positive cultures; among them were isolated extended spectrum beta-lactamase producers and carbapenem-resistant strains. Yeast-like fungi comprised 15.5% of positive cultures. In conclusion, we observed predominantly Gram-positive bacteria, comprising 65.5% of isolates. The increased proportion of multi-drug-resistant bacterial isolates may be due to the frequent prophylaxis of bacterial infections in patients.     

Urinary Tract Infections in the Early Posttransplant Period After Simultaneous Pancreas–Kidney Transplantation

Objective

Urinary tract infection (UTI) is among the common infection in simultaneous pancreas-kidney transplantation (SPKT).

Patients and Methods

The study included 26 adult patients undergoing SPKT between September 2001 and December 2006. All the patients were followed prospectively for UTI during the first 4 weeks after surgery. Urine samples were investigated for bacteriologic cultures. The micro-organisms were identified in accordance with standard bacteriologic procedures. Susceptibility testing was carried out using Clinical and Laboratory Standards Institute (CLSI) procedures.

Results

Among 77 urine specimens obtained from all recipients during the first month, there were 30 isolated bacterial strains. The most common were Gram-positive bacteria (53.3%) with predominance of enterococci (75%) associated with high levels of aminoglycoside resistant strains (HLAR; 58.3%) and vancomycin-resistant strains (VRE; 25%). Gram-negative bacteria were detected in 46.7% of positive cultures.

Conclusions

In our study, enterococci predominated as 75% of Gram-positive isolates. The increased proportion of multi-drug-resistant bacteria, which can caused severe UTI in patients after SPKT, may be due to the frequent use of prophylaxis of bacterial infections in patients.     

Late Ureteral Stenosis After Kidney Transplantation: A Single-Center Experience

In a retrospective study, we analyzed 1419 consecutive kidney transplantation procedures performed at a single center to identify potential predictive factors of ureteral stenosis. Only stenosis observed after the first month posttransplantation was considered. The Cox proportional hazard regression model was used to analyze donor age and serum creatinine concentration before procurement, recipient age, cold ischemia time, delayed graft function, number of renal arteries, and presence of a double-J stent. Follow-up evaluation included number and timing of acute rejection episodes, cytomegalovirus infection, acute pyelonephritis, renal function, and patient death. Ureteral stenosis developed in 45 patients (3.17%), and was correlated with donor age older than 65 years (P = .001), kidneys with more than 2 arteries (P = .009), and delayed graft function (P = .02). The data suggest a potential protective role of donor age, number of renal arteries, and delayed graft function in development of ureteral stenosis after kidney transplantation.     

Nutritional Parameters in Early and Late Kidney Transplantation

BackgroundKidney transplantation (KT) has the advantage of providing a better quality of life and freedom for the patient. However, nutritional changes can occur, with clinical repercussions. The aim of the study was to compare the nutritional status in the initial and late post-KT period.MethodsA cross-sectional study was conducted involving 169 outpatients post-KT. Clinical, demographic, biochemical, food intake, handgrip strength (HGS), and anthropometric data were collected from medical records for the first nutritional care after KT. Statistical tests were performed to compare the groups according to the time of KT: early (≤1 year) and late (>1 year). The level of significance adopted was 5%.ResultsThe median age of the patients was 46 years (range, 38-57), 50.3% were men, and it was observed that 66.9% underwent KT with a deceased donor. There was a higher prevalence of diabetes mellitus (42.6% vs 23.5%; P = .011), and higher body mass index (28.80 ± 7.26 vs 26.51 ± 6.62 kg/m²; P = .046), arm muscle circumference (25.84 ± 4.63 vs 24.09 ± 3.36 cm; P = .019), and HGS (26.97 ± 10.70 vs 20.21 ± 10.83 kg; P = .010) in patients with late KT. Linear regression analysis showed that at each log of time, there was an increase of 1.90 kg in HGS (P = .045) and 0.48 cm (P = .036) in mid-arm muscle circumference.ConclusionThe present study demonstrated that late kidney transplantation was associated with higher values of body mass index, mid-arm muscle circumference, and HGS.     

Cardiac Troponin T Before and After Kidney Transplantation: Determinants and Implications for Posttransplant Survival

Pretransplant cardiac troponin T(cTnT_pre) is a significant predictor of survival postkidney transplantation. We assessed correlates of cTnT levels pre‐ and posttransplantation and their relationship with recipient survival. A total of 1206 adult recipients of kidney grafts between 2000 and 2010 were included. Pretransplant cTnT was elevated (≥0.01 ng/mL) in 56.4%. Higher cTnT_pre was associated with increased risk of posttransplant death/cardiac events independent of cardiovascular risk factors. Elevated cTnT_pre declined rapidly posttransplant and was normal in 75% of recipients at 3 weeks and 88.6% at 1 year. Elevated posttransplant cTnT was associated with reduced patient survival (cTnT_3wks: HR = 5.575, CI 3.207–9.692, p < 0.0001; cTnT_1year: 3.664, 2.129–6.305, p < 0.0001) independent of age, diabetes, pretransplant dialysis, heart disease and allograft function. Negative/positive predictive values for high cTnT_3wks were 91.4%/50% respectively. Normalization of cTnT posttransplant was associated with reduced risk. Variables related to elevated cTnT posttransplant included pretransplant diabetes, older age, time on dialysis, high cTnT_pre and lower graft function. Patients with delayed graft function and those with GFR < 30 mL/min at 3 weeks were more likely to have an elevated cTnT_3wks and remained at high risk. When allografts restore sufficient kidney function cTnT normalizes and patient survival improves. Lack of normalization of cTnT posttransplant identifies a group of individuals with high risk of death/cardiac events.     

Frailty and Early Hospital Readmission After Kidney Transplantation

Early hospital readmission (EHR) after kidney transplantation (KT) is associated with increased morbidity and higher costs. Registry‐based recipient, transplant and center‐level predictors of EHR are limited, and novel predictors are needed. We hypothesized that frailty, a measure of physiologic reserve initially described and validated in geriatrics and recently associated with early KT outcomes, might serve as a novel, independent predictor of EHR in KT recipients of all ages. We measured frailty in 383 KT recipients at Johns Hopkins Hospital. EHR was ascertained from medical records as ≥1 hospitalization within 30 days of initial post‐KT discharge. Frail KT recipients were much more likely to experience EHR (45.8% vs. 28.0%, p = 0.005), regardless of age. After adjusting for previously described registry‐based risk factors, frailty independently predicted 61% higher risk of EHR (adjusted RR = 1.61, 95% CI: 1.18–2.19, p = 0.002). In addition, frailty improved EHR risk prediction by improving the area under the receiver operating characteristic curve (p = 0.01) as well as the net reclassification index (p = 0.04). Identifying frail KT recipients for targeted outpatient monitoring and intervention may reduce EHR rates.     

Early Rehospitalization After Kidney Transplantation: Assessing Preventability and Prognosis

Early rehospitalization after kidney transplantation (KT) is common and may predict future adverse outcomes. Previous studies using claims data have been limited in identifying preventable rehospitalizations. We assembled a cohort of 753 adults at our institution undergoing KT from January 1, 2003 to December 31, 2007. Two physicians independently reviewed medical records of 237 patients (32%) with early rehospitalization and identified (1) primary reason for and (2) preventability of rehospitalization. Mortality and graft failure were ascertained through linkage to the Scientific Registry of Transplant Recipients. Leading reasons for rehospitalization included surgical complications (15%), rejection (14%), volume shifts (11%) and systemic and surgical wound infections (11% and 2.5%). Reviewer agreement on primary reason (85% of cases) was strong (kappa = 0.78). Only 19 rehospitalizations (8%) met preventability criteria. Using logistic regression, weekend discharge (odds ratio [OR] 1.59, p = 0.01), waitlist time (OR 1.10, p = 0.04) and longer initial length of stay (OR 1.42, p = 0.03) were associated with early rehospitalization. Using Cox regression, early rehospitalization was associated with mortality (hazard ratio [HR] 1.55; p = 0.03) but not graft loss (HR 1.33; p = 0.09). Early rehospitalization has diverse causes and presents challenges as a quality metric after KT. These results should be validated prospectively at multiple centers to identify vulnerable patients and modifiable processes‐of‐care.     

Comparative Analysis of Arterial Stiffness and Body Composition in Early and Late Periods After Kidney Transplantation

Introduction

Diseases of the cardiovascular system are the most common cause of death in patients after kidney transplantation (KTx). Pulse wave velocity (PWV) measurement is a simple, noninvasive, and increasingly popular method to assess arterial stiffness, and thus to assess cardiovascular risk. The aim of the study was to compare arterial stiffness and body composition in patients after KTx in the early and late postoperative periods.

Late Conversion to Belatacept After Kidney Transplantation: Outcome and Prognostic Factors

Background

Conversion to belatacept at a later point after kidney transplantation (KT) as a rescue therapy has been shown to be beneficiary in an increasing number of patients, but prognostic factors for a favorable outcome have never been investigated.

Early Graft Loss After Kidney Transplantation: Risk Factors and Consequences

Early graft loss (EGL) after kidney transplantation is a catastrophic outcome that is assumed to be more likely after the use of kidneys from suboptimal donors. We therefore examined its incidence, risk factors and consequences in our center in relation to different donor types. Of 801 recipients who received a kidney‐only transplant from deceased donors, 50 (6.2%) suffered EGL within 30 days of transplantation. Significant risks factors for EGL were donation after circulatory death (DCD) (odds ratio [OR] 2.88; p = 0.006), expanded criteria donor (ECD) transplantation (OR 4.22; p = 0.010), donor age (OR 1.03; p = 0.044) and recipient past history of thrombosis (OR 4.91; p = 0.001). Recipients with EGL had 12.28 times increased risk of death within the first year, but long‐term survival was worse for patients remaining on the waiting list. In comparison with patients on the waiting list but not transplanted, and with all patients on the waiting list, the risk of death after EGL decreased to baseline 4 and 23 months after transplantation, respectively. Our findings suggest that DCD and ECD transplantation are significant risk factors for EGL, which is a major risk factor for recipient death. However, long‐term mortality is even greater for those remaining on the waiting list.     

Early Urine Output Predicts Graft Survival After Kidney Transplantation

Background

In kidney transplantations, the identification of early postoperative parameters with high predictive power for the development of late allograft dysfunction has important implications for clinical practice. This study sought to determine these parameters in a single-center cohort.

Methods

We studied 82 deceased donor renal transplantation. We assessed the following measures: dialysis-dependent delayed graft function (ddDGF), extended DGF, serum creatinine level at day 7, creatinine reduction ratio at day 7, urine output at day 1 and at day 7 posttransplantation (UO7).

Results

Only UO7 showed a significant result upon multivariate analysis (P < .0001). It was less influenced by dialysis with respect to measures based upon serum creatinine. By Receiver Operating characteristic (ROC) analysis, it showed an elevated area under the curve (0.811), with a cut-off value of 500 mL/24 h, showing high sensitivity (98.5%).

Conclusions

UO7 may be of clinical utility to assess the risk for subsequent renal dysfunction.     

Early Steroid Withdrawal After Kidney Transplantation in Patients at Risk for New-Onset Diabetes After Transplantation

BackgroundNew-onset diabetes after transplantation (NODAT) is a serious complication after kidney transplantation because of worse graft survival and increased risk of cardiovascular events. It is partly induced by immunosuppressive therapies such as corticosteroids. This study aimed to assess whether early corticosteroid withdrawal on day 4 (early steroid withdrawal [ESW] group) could prevent the development of NODAT within 2 years posttransplantation while maintaining good graft and patient survival rates.MethodsThis was an observational, single-center, retrospective study. All patients received an induction therapy of antithymocyte globulin or basiliximab and maintenance therapy of tacrolimus/mycophenolate mofetil/corticosteroids. Patients were either weaned off corticosteroids on day 4 (ESW group) or were maintained on corticosteroids for at least 3 months (standard group). NODAT was defined as the initiation of any oral hypoglycemic agent or insulin at 3 months and up to 2 years posttransplantation in previously nondiabetic recipients.ResultsBetween January, 1, 2010, and December 14, 2014, 492 recipients were included in this study; 88 received the ESW strategy, and 404 received the standard strategy. Age and body mass index (BMI) were significantly higher in the ESW group. The incidence of NODAT was 36.8% in the ESW group and 8.8% in the standard group (odds ratio [OR], 47.5; P < .001). Compared with a matched sample from the standard group that had the same probability to benefit from ESW at baseline, ESW was still associated with a significantly increased risk of NODAT (OR, 4.41; P = .018). Among recipients with a BMI >25 kg/m², the ESW strategy significantly decreased the risk of NODAT compared with the standard strategy (OR, 0.07; P = .013). Safety endpoints (eg, acute rejection, de novo–specific antibodies, graft function/survival) did not differ between groups.ConclusionDespite a reassuring safety profile, ESW on day 4 after kidney transplantation only had a marginal effect on the incidence of NODAT.     

Clinical Characteristics of Late-Onset Cytomegalovirus Infection After Kidney Transplantation

BackgroundLate-onset cytomegalovirus (CMV) infection (LCI) has been emerging mong solid-organ transplant recipients. We explored clinical characteristics, risk factors, and outcomes of LCI in kidney transplantation (KT) recipients.MethodsA retrospective study of all adult KT recipients with LCIs (that occurred >6 months after transplant) from 2016 to 2018 was conducted. Clinical characteristics and outcomes were extracted. Risk factors of LCI were analyzed using Cox proportional hazards models.ResultsA total of 518 KT recipients were included. Ninety-eight percent had donor CMV-seropositive and recipient CMV-seropositive status (D+/R+). Ten (2%) KT recipients developed LCI with a median onset of 14 (interquartile range, 8-15) months. Those included asymptomatic CMV infection (40%) and tissue-invasive disease (60%). CMV D+/R– serostatus and a prior episode of rejection within 6 months were associated with LCI (hazard ratio, 17.35; 95% confidence interval, 3.60-83.63; P < .001) and (hazard ratio, 38.15; 95% confidence interval, 6.15-236.72; P < .001), respectively. There was no difference in the rate of allograft failure and mortality in those with LCI compared with those with early-onset CMV infection.ConclusionLCI is uncommon after KT. Those with CMV seromismatch and a prior episode of rejection were more likely to develop LCI. Clinical and allograft outcomes were not different among each group.     

Effect of Teriparatide on Early Bone Loss After Kidney Transplantation

Kidney transplantation is associated with bone loss and a high risk of fractures. Prophylactic treatment of bone is therefore recommended in the early posttransplant period. As a large number of transplant recipients develop adynamic renal osteodystrophy, recombinant parathyroid hormone (rPTH) could be a promising therapeutic option.
In a 6-month double-blind, randomized trial, 26 kidney transplant recipients were treated with daily subcutaneous injections of 20 μg teriparatide (PTH 1–34) or placebo. Bone mineral density (BMD) of the femoral neck, lumbar spine and radial bone was measured at transplantation and after 6 months. Paired bone biopsies for histomorphometric analysis were obtained in six, and for measurement of bone matrix mineralization in five patients of each group. Serologic bone markers were measured at baseline and every 3 months.
A total of 24 out of 26 patients completed the study. Femoral neck BMD was stable in the teriparatide group, but decreased significantly in the placebo group. Lumbar spine and radial BMD, histomorphometric bone volume and bone matrix mineralization status remained unchanged in both groups. Serologic bone markers were similarly reduced in both groups throughout the study.
We conclude that teriparatide does not improve BMD early after kidney transplantation. Neither histological analysis nor bone markers provide evidence of improved bone turnover or mineralization.     

Death After Graft Loss: An Important Late Study Endpoint in Kidney Transplantation

Traditional study endpoints utilized in renal transplantation have included graft survival, and death with a functioning graft. We analyzed the risk factors for death after allograft loss (DAGL) among a total of 78564 primary renal transplants reported to the United States Renal Data System (USRDS) from 1988 to 1998. Cox models were used to investigate risk factors for DAGL. Of 15528 deaths, 10816 occurred before, and 4712 occurred after graft loss. Overall annual adjusted death rates were more than 3-fold higher after graft loss as compared to before graft loss (9.42% vs. 2.81%). By Cox model, dialysis for more than 2 years was associated with a more than 2-fold relative risk for DAGL (RR = 2.2, Cl = 1.88-2.53), while transplant time was not associated with DAGL. Infection related graft losses showed a strong association with DAGL (RR = 1.64, Cl = 1.31-2.07). Acute rejection and thrombosis as causes of graft loss were also significantly associated with the risk for DAGL (RR = 1.35, Cl = 1.23-1.47 and RR = 1.39, Cl = 1.39). Patient survival after graft loss is poor. The lack of association between DAGL and transplant time, as opposed to the strong relation to pretransplant dialysis time, would suggest the adverse effects of previous uremia-mediated damage may be contributing to this phenomenon, along with the adverse effects of loss of renal function.     

Kidney Allograft Fibrosis and Atrophy Early After Living Donor Transplantation

Kidney allograft failure is most often caused by chronic allograft nephropathy, a process of interstitial fibrosis (GIF) and tubular atrophy (TA). We assessed the pathology of living donor (LD) grafts compared to deceased donor (DD). Included are 321 recipients (245 LD; 76 DD) with protocol biopsies the first 2 years of transplant. In LD, GIF was present in 7%, 31%, 61% and 71% of grafts at 0, 4, 12 and 24 months. TA progressed in parallel to GIF. Compared to LD, more DD grafts had GIF at time 0 (29%, p = 0.002); thereafter the incidence of GIF was similar. In LD, GIF was associated with lower glomerular filtration rate (GFR)(1 year) (no GIF, 62 +/- 16; GIF, 49 +/- 15 mL/min/m(2) iothalamate clearance, p = 0.001) and reduced graft survival (HR = 2.2, p = 0.009). GIF in LD related to acute rejection (HR = 2.6, p = 0.01), polyoma nephropathy (OR = 4.4, p = 0.02) and lower levels of GFR 3 weeks post-transplant (HR = 0.961; p = 0.03, multivariate). However, GIF also developed in 53% of recipients lacking these covariates. Thus, GIF/TA develops in the majority of LD grafts, it is often mild but is associated with reduced function and survival. GIF frequently develops in the absence of risk factors. Lower GFR post-transplant identify patients at highest risk of GIF.