Multivariable analysis of risk factors in renal transplantation

The aim of this thesis is to make a distinction between potentially important variables in their influence on the risk of failure after renal transplantation. Which of the known variables really influence our results? Which variables can be neglected? Most studies on this subject are univariable analysis. In these studies selection and inter-dependency of the influence of variables cannot be taken into account. Besides, the importance of the influence of different variables is studied in different analyses and cannot be compared. Multivariable analysis with the Cox proportional hazards analysis offers best prospects to compare the influences of different variables on the failure risk. In the next chapter we describe how the Cox deals with our question and how risk factors are defined. Our principal motivation was to come to an understanding of the reasons for failure after renal transplantation. With this knowledge we could try to decrease the prevalence of high risk or combination of high risk factors in recipient

Living Donor Kidney Transplantation Should Be Promoted among "elderly" Patients

Background. Age criteria for kidney transplantation have been liberalized over the years resulting in more waitlisted elderly patients. What are the prospects of elderly patients on the waiting list? Methods. Between 2000 and 2013, 2622 patients had been waitlisted. Waiting time was defined as the period between dialysis onset and being delisted. Patients were categorized according to age upon listing: 64 years. Furthermore, the influence of ABO blood type and panel reactive antibodies on outflow patterns was studied. Results. At the end of observation (November 2017), 1957 (75%) patients had been transplanted, 333 (13%) had been delisted without a transplantation, 271 (10%) had died, and 61 (2%) were still waiting. When comparing the age categories, outflow patterns were completely different. The percentage of patients transplanted decreased with increasing age, while the percentage of patients that had been delisted or had died increased with increasing age, especially in the population without living donor. Within 6 years, 93% of the population 55 years, 39% received a living donor kidney, while >50% of patients without a living donor had been delisted/died. Multivariable analysis showed that the influence of age, ABO blood type, and panel reactive antibodies on outflow patterns was significant, but the magnitude of the influence of the latter 2 was only modest compared with that of age. Conclusions. "Elderly" (not only >64 y but even 55-64 y) received a living donor kidney transplantation less often. Moreover, they cannot bear the waiting time for a deceased donor kidney, resulting in delisting without a transplant in more than half the population of patients without a living donor. Promoting living donor kidney transplantation is the only modification that improves transplantation and decreases delisting/death on the waiting list in this population

Systematic Surgical Assessment of Deceased-Donor Kidneys as a Predictor of Short-Term Transplant Outcomes

Background: Short-term kidney graft dysfunction is correlated with complications and it is associated with a decreased long-term survival; therefore, a scoring system to predict short-term renal transplant outcomes is warranted. Aim: The aim of this study is to quantify the impression of the organ procurement surgeon in correlation with the following kidney transplant outcomes: immediate graft function (IGF), delayed graft function (DGF), and primary nonfunction (PNF). Results are compared to factors associated with the 1-year outcome. Methods: A regional prospective pilot study was performed using deceased-donor organ assessment forms to be filled out by procurement surgeons after procurement. Data were gathered on kidney temperature, perfusion, anatomy, atherosclerosis, and overall quality. Results: Included were 90 donors who donated 178 kidneys, 166 of which were transplanted. Variables that were significantly more prevalent in the DGF-or-PNF group (n = 65) are: large kidney size (length, p = 0.008; width, p = 0.036), poor perfusion quality (p = 0.037), lower diuresis (p = 0.039), fewer hypotensive episodes (p = 0.003), and donation-after-circulatory-death donors (p = 0.017). Multivariable analysis showed that perfusion quality and kidney width significantly predicted the short-term outcome. However multivariable analysis of long-term outcomes showed that the first measured donor creatinine, kidney donor risk index, IGF vs. DGF+PNG, and kidney length predicted outcomes. Conclusions: Results show that short-term graft function and 1-year graft function indeed are influenced by different variables. DGF and PNF occur more frequently in kidneys with poor perfusion and in larger kidneys. A plausible explanation for this is that these kidneys might be insufficiently washed out, or even congested, which may predispose to DGF. These kidneys would probably benefit most from reconditioning strategies, such as machine perfusion. A scoring system including these variables might aid in decision-making towards allocation and potential reconditioning strategies

Antegrade balloon dilatation as a treatment option for posttransplant ureteral strictures: Case series of 50 patients

Objectives: The aim of this study was to investigate the effects of antegrade balloon dilatation on ureteral strictures that developed after kidney transplant. Materials and Methods: The hospital databases of the Erasmus Medical Center (Rotterdam, The Netherlands) and the Academic Medical Center (Amsterdam, The Netherlands) were retrospectively screened for patients who underwent balloon dilatation after kidney transplant. Balloon dilatation was technically successful whenever it was able to pass the strictured segment with the guidewire followed by balloon inflation; the procedure was clinically successful if no further interventions (for example, surgical revision of the ureteroneocystostomy or prolonged double J placement) were necessary. Results: Fifty patients (2.4%) of 2075 kidney transplant recipients underwent antegrade balloon dilatation because of urinary outflow obstruction. Median time between transplant and balloon dilatation was 3 months (range, 0-139 mo). In 43 patients (86%), balloon dilatation was technically successful. In the remaining 7 patients (14%), it was impossible to pass the strictured segment with the guidewire. In 20 of 43 patients (47%) having a technically successful procedure, the procedure was also clinically successful, with median follow-up after balloon dilatation of 35.5 months (range, 0-102 mo). We did not identify any patient o

Independent risk factors for urological complications after deceased donor kidney transplantation

Urological complications after kidney transplantation are mostly related to the ureteroneocystostomy, often requiring interventions with additional costs, morbidity and mortality. Our aim was to assess risk factors for urological complications in deceased donor kidney transplantation. Between January 2000 and December 2011, 566 kidney transplantations were performed with deceased donor kidneys. Recipients were divided in a group with, and a group without urological complications, defined as the need for a percutaneous nephrostomy catheter or surgical revision of the ureteroneocystostomy. Univariate and multivariate analyses were performed. Univariate analysis showed increased number of male donors (p = 0.041), male recipients (p = 0.002), pre-emptively transplanted recipients (p = 0.007), and arterial reconstructions (p = 0.004) in the group with urological complications. Less urological complications occurred in recipients on hemodialysis (p = 0.005). More overall surgical interventions (p<0.001), surgical site infections (p = 0.042), urinary tract infections (p<0.001) and lymphoceles (p<0.001) occurred in the group with urological complications. Multivariate analysis showed that male recipients (p = 0.010) and arterial reconstructions (p = 0.019) were independent risk factors. No difference was found between both groups in patient or graft survival. In conclusion, recipient male gender and arterial reconstruction are independent risk factors for urological complications after deceased donor kidney transplantation. Nevertheless, graft and recipient survival is not different between both groups

The prognosis of kidney transplant recipients with aorto-iliac calcification: a systematic review and meta-analysis

The prognosis of kidney transplant recipients (KTR) with vascular calcification (VC) in the aorto-iliac arteries is unclear. We performed a systematic review and meta-analysis to investigate their survival outcomes. Studies from January 1st, 2000 until March 5th, 2019 were included. Outcomes for meta-analysis were patient survival, (death-censored) graft survival and delayed graft function (DGF). Twenty-one studies were identified, eight provided data for meta-analysis. KTR with VC had a significantly increased mortality risk [1-year: risk ratio (RR) 2.19 (1.39–3.44), 5-year: RR 2.28 (1.86–2.79)]. The risk of 1-year graft loss was three times higher in recipients with VC [RR 3.15 (1.30–7.64)]. The risk of graft loss censored for death [1-year: RR 2.26 (0.58–2.73), 3-year: RR 2.19 (0.49–9.82)] and the risk of DGF (RR 1.24, 95% CI 0.98–1.58) were not statistically different. The quality of the evidence was rated as very low. To conclude, the presence of VC was associated with an increased mortality risk and risk of graft loss. In this small sample size, no statistical significant association between VC and DGF or risk of death-censored graft loss could be demonstrated. For interpretation of the outcomes, the quality and sample size of the evidence should be taken into consideration

Clinical outcome of kidney transplantation after bariatric surgery: A single-center, retrospective cohort study

Patients with class II and III obesity and end-stage renal disease are often ineligible for kidney transplantation (KTx) due to increased postoperative complications and technically challenging surgery. Bariatric surgery (BS) can be an effective solution for KTx candidates who are considered inoperable. The aim of this study is to evaluate outcomes of KTx after BS and to compare the outcomes to obese recipients (BMI ≥ 35 kg/m2) without BS. This retrospective, single-center study included patients who received KTx after BS between January 1994 and December 2018. The primary outcome was postoperative complications. The secondary outcomes were graft and patient survival. In total, 156 patients were included, of whom 23 underwent BS prior to KTx. There were no significant differences in postoperative complications. After a median follow-up of 5.1 years, death-censored graft survival, uncensored graft survival, and patient survival were similar to controls (log rank test p =.845,.659, and.704, respectively). Dialysis pre-transplantation (Hazard Ratio (HR) 2.55; 95%CI 1.03–6.34, p =.043) and diabetes (HR 2.41; 95%CI 1.11–5.22, p =.027) were independent risk factors for all-cause mortality. A kidney from a deceased donor was an independent risk factor for death-censored graft loss (HR 1.98; 95%CI 1.04–3.79, p =.038). Patients who received a KTx after BS have similar outcomes as obese transplant recipients

Resolution of IgM Nephropathy After Rituximab Treatment

Immunoglobulin M (IgM) nephropathy is an idiopathic glomerulonephritis characterized by mesangial deposits of IgM. IgM nephropathy presenting with proteinuria, especially nephrotic syndrome, frequently is steroid dependent or steroid resistant and associated with reaching end-stage renal disease after a 15-year follow-up. Because no long-term effective treatment is known for patients with IgM nephropathy, there is a clear need for therapeutic alternatives. We describe a patient who reached end-stage renal disease 20 years after IgM nephropathy was diagnosed at the age of 3 years. IgM nephropathy recurred after kidney transplantation, leading to microscopic hematuria and proteinuria. High-dose steroid therapy was not effective, and kidney function slowly decreased. Three years after transplantation, 2 doses of rituximab were administered, leading to complete remission of the IgM nephropathy. One year after rituximab treatment, the patient has stable kidney function, normal urinary sediment, and no proteinuria. Rituximab may be a valuable novel therapeutic drug for the treatment of patients with IgM nephropathy. Am J Kidney Dis 53:1059-1062. (C) 2009 by the National Kidney Foundation, Inc

Oxalate deposition in renal allograft biopsies within 3 months after transplantation is associated with allograft dysfunction

Background Calcium oxalate (CaOx) deposition in the kidney may lead to loss of native renal function but little is known about the prevalence and role of CaOx deposition in transplanted kidneys. Methods In patients transplanted in 2014 and 2015, all for-cause renal allograft biopsies obtained within 3 months post-transplantation were retrospectively investigated for CaOx deposition. Additionally, all preimplantation renal biopsies obtained in 2000 and 2001 were studied. Results In 2014 and 2015, 388 patients were transplanted, of whom 149 had at least one for-cause renal biopsy. Twenty-six (17%) patients had CaOx deposition. In the population with CaOx deposition: Patients had significantly more often been treated with dialysis before transplantation (89 vs. 64%; p = 0.011); delayed graft function occurred more frequently (42 vs. 23%; p = 0.038); and the eGFR at the time of first biopsy was significantly worse (21 vs. 29 ml/ min/1.73m 2 ; p = 0.037). In a multivariate logistic regression analysis, eGFR at the time of first biopsy (OR 0.958, 95%-Cl: 0.924–0.993, p = 0.019), dialysis before transplantation (OR 4.868, 95%-Cl: 1.128–21.003, p = 0.034) and the time of first biopsy after transplantation (OR 1.037, 95%-Cl: 1.013–1.062, p = 0.002) were independently associated with CaOx deposition. Graft survival censored for death was significantly worse in patients with CaOx deposition (p = 0.018). In only 1 of 106 preimplantation biopsies CaOx deposition was found (0.94%). Conclusion CaOx deposition appears to be primarily recipient-derived and is frequently observed in for-cause renal allograft biopsies obtained within 3 months post-transplantation. It is associated with inferior renal function at the time of biopsy and worse graft survival