Does Kidney Donor Risk Index implementation lead to the transplantation of more and higher-quality donor kidneys?

BACKGROUND: The Kidney Donor Risk Index (KDRI) is a quantitative evaluation of the quality of donor organs and is implemented in the US allocation system. This single-centre study investigates whether the implementation of the KDRI in our decision-making process to accept or decline an offered deceased donor kidney, increases our acceptance rate. METHODS: From April 2015 until December 2016, we prospectively calculated the KDRI for all deceased donor kidney offers allocated by Eurotransplant to our centre. The number of the transplanted versus declined kidney offers during the study period were compared to a historical set of donor kidney offers. RESULTS: After implementation of the KDRI, 26.1% (75/288) of all offered donor kidneys were transplanted, compared with 20.7% (136/657) in the previous period (P < 0.001). The median KDRI of all transplanted donor kidneys during the second period was 0.97 [Kidney Donor Profile Index (KDPI) 47%], a value significantly higher than the median KDRI of 0.85 (KDPI 34%) during the first period (P = 0.047). A total of 68% of patients for whom a first-offered donor kidney was declined during this period were transplanted after a median waiting time of 386 days, mostly with a lower KDRI donor kidney. CONCLUSIONS: Implementing the KDRI in our decision-making process increased the transplantation rate by 26%. The KDRI can be a supportive tool when considering whether to accept or decline a deceased donor kidney offer. More data are needed to validate this score in other European centres.

Longterm results of liver transplantation from donation after circulatory death.

Donation after circulatory death (DCD) liver transplantation (LT) may imply a risk for decreased graft survival, caused by posttransplantation complications such as primary nonfunction or ischemic-type biliary lesions. However, similar survival rates for DCD and donation after brain death (DBD) LT have been reported. The objective of this study is to determine the longterm outcome of DCD LT in the Eurotransplant region corrected for the Eurotransplant donor risk index (ET-DRI). Transplants performed in Belgium and the Netherlands (January 1, 2003 to December 31, 2007) in adult recipients were included. Graft failure was defined as either the date of recipient death or retransplantation whichever occurred first (death-uncensored graft survival). Mean follow-up was 7.2 years. In total, 126 DCD and 1264 DBD LTs were performed. Kaplan-Meier survival analyses showed different graft survival for DBD and DCD at 1 year (77.7% versus 74.8%, respectively; P = 0.71), 5 years (65.6% versus 54.4%, respectively; P = 0.02), and 10 years (47.3% versus 44.2%, respectively; P = 0.55; log-rank P = 0.038). Although there was an overall significant difference, the survival curves almost reach each other after 10 years, which is most likely caused by other risk factors being less in DCD livers. Patient survival was not significantly different (P = 0.59). Multivariate Cox regression analysis showed a hazard ratio of 1.7 (P < 0.001) for DCD (corrected for ET-DRI and recipient factors). First warm ischemia time (WIT), which is the time from the end of circulation until aortic cold perfusion, over 25 minutes was associated with a lower graft survival in univariate analysis of all DCD transplants (P = 0.002). In conclusion, DCD LT has an increased risk for diminished graft survival compared to DBD. There was no significant difference in patient survival. DCD allografts with a first WIT > 25 minutes have an increased risk for a decrease in graft survival. Liver Transplantation 22 1107-1114 2016 AASLD.

"Does Perioperative Patient Perfusion Obviate the Need for Kidney Machine Perfusion?" A Retrospective Analysis of Patients Receiving a Kidney From "Donation After Circulatory Death" Donors.

BACKGROUND: Delayed graft function (DGF) remains a clinically relevant problem in the post-transplant period, especially in patients with a renal graft from a "donation after cardiac death" (DCD) donor. Controversy exists around the optimal perioperative fluid therapy in such patients. These patients may benefit from a perioperative saline loading fluid protocol, which may reduce the risk of DGF. METHODS: We compared 2 cohorts of patients who underwent a renal transplantation with a graft from a DCD donor. From January 2003 until December 2012, patients (N = 46) were hemodynamically managed at the discretion of the care-giving physician, without a preoperative fluid administration protocol (first study period). From January 2015 until March 2019 (N = 26), patients received saline loading before, during, and after kidney transplantation according to a well-defined saline loading fluid protocol (second study period). The relationship between the use of this perioperative fluid protocol and DGF was analyzed using univariable and multivariable logistic regression models. RESULTS: DGF occurred in 11 of 46 (24%) patients in the first study period and in 1 of 26 (4%) in the second study period (P < .05). In a multivariable model, correcting for cold ischemia time and Kidney Donor Risk Index, the use of a saline loading fluid protocol in the perioperative phase was nearly significantly associated with a decrease in DGF (P = .07). CONCLUSION: In our DCD transplant population, DGF rates were low. Our data further strongly suggest that implementation of a perioperative saline loading fluid protocol was independently associated with a lower risk of DGF.

Diagnostic and therapeutic double-balloon enteroscopy after small bowel Roux-en-Y reconstructive surgery.

BACKGROUND: Roux-en-Y reconstruction excludes the afferent limb and the biliopancreatic system from conventional endoscopic access. Postoperative problems in these excluded gastrointestinal systems are therefore often dealt with surgically. We investigated the usefulness of the therapeutic double-balloon enteroscope to perform interventional endoscopic procedures in the excluded segment of the gastrointestinal tract after Roux-en-Y reconstruction. METHODS: 30 procedures were performed in 22 patients with Roux-en-Y reconstruction after enterobiliary anastomosis, gastrectomy or bariatric gastric bypass. All procedures were performed with the therapeutic double-balloon enteroscope, under general anesthesia and with fluoroscopic control. RESULTS: ERCP at the enterobiliary anastomosis was successful in 90% (n = 10) of the procedures. ERCP at the intact papilla was successful in 60% (n = 5). Enterocutaneous fistula closure after (sub)total gastrectomy was performed in 2 procedures. Successful diagnostic procedures encompassed intubation of the excluded stomach after bariatric gastric bypass (89%, n = 9) or the afferent limb after Roux-en-Y reconstruction (75%, n = 4). The overall success rate in accessing the aimed excluded segment with the double-balloon enteroscope was 87%. Interventional procedures were able to avoid surgery in 65%. One retroperitoneal perforation occurred during ERCP which was conservatively treated. CONCLUSIONS: Excluded gastrointestinal segments after Roux-en-Y reconstruction can be accessed with a substantial success rate using double-balloon enteroscopy. Therapeutic interventions like ERCP can prevent surgery in the majority of patients.

Chronic allograft nephropathy: what have we learned from protocol biopsies?

Chronic allograft nephropathy, characterized by interstitial fibrosis and tubular atrophy, is still a major cause of graft loss after kidney transplantation. The complex pathophysiology of chronic allograft nephropathy is still poorly understood, and could be clarified by a more systematic performance of implantation and protocol biopsies of the renal allograft. This review highlights the contribution of implantation and protocol biopsies to our current knowledge of the complex interaction of multiple processes, ultimately leading to the development of interstitial fibrosis and tubular atrophy in the transplanted kidney. In addition, the safety and the limitations of protocol biopsies are discussed, as well as potential future directions for clinical practice and clinical research.

Prediction of delayed graft function using different scoring algorithms: A single-center experience.

AIM: To compare the performance of 3 published delayed graft function (DGF) calculators that compute the theoretical risk of DGF for each patient. METHODS: This single-center, retrospective study included 247 consecutive kidney transplants from a deceased donor. These kidney transplantations were performed at our institution between January 2003 and December 2012. We compared the occurrence of observed DGF in our cohort with the predicted DGF according to three different published calculators. The accuracy of the calculators was evaluated by means of the c-index (receiver operating characteristic curve). RESULTS: DGF occurred in 15.3% of the transplants under study. The c index of the Irish calculator provided an area under the curve (AUC) of 0.69 indicating an acceptable level of prediction, in contrast to the poor performance of the Jeldres nomogram (AUC = 0.54) and the Chapal nomogram (AUC = 0.51). With the Irish algorithm the predicted DGF risk and the observed DGF probabilities were close. The mean calculated DGF risk was significantly different between DGF-positive and DGF-negative subjects (P < 0.0001). However, at the level of the individual patient the calculated risk of DGF overlapped very widely with ranges from 10% to 51% for recipients with DGF and from 4% to 56% for those without DGF. The sensitivity, specificity and positive predictive value of a calculated DGF risk ≥ 30% with the Irish nomogram were 32%, 91% and 38%. CONCLUSION: Predictive models for DGF after kidney transplantation are performant in the population in which they were derived, but less so in external validations.

Bilateral adrenal haemorrhage and acute adrenal insufficiency in a blunt abdominal trauma: a case-report and literature review.

Blunt abdominal trauma is frequently associated with adrenal haemorrhage, and is preferentially diagnosed by computed tomography scan. Lesions are mostly unilateral and asymptomatic and are therefore frequently overlooked. Bilateral haemorrhage, however, has a high mortality rate as a result of acute adrenal insufficiency. We report on a 30-year-old polytraumatic patient who developed cardiocirculatory arrest when all lesions were surgically controlled and stable and without evidence of a primary cardiac problem. Autopsy revealed bilateral adrenal haemorrhage, leading to the diagnosis of acute adrenal insufficiency as the cause of death. We conclude that adrenal haemorrhage should be looked for in every polytrauma patient, and that although it is a rare occurrence, acute adrenal insufficiency caused by bilateral adrenal haemorrhage should be considered in every patient with unexplained cardiocirculatory failure. Such patients may benefit from the prompt administration of corticosteroid replacement, which can be life saving.

Clinical potential of intravenous neural stem cell delivery for treatment of neuroinflammatory disease in mice?

While neural stem cells (NSCs) are widely expected to become a therapeutic agent for treatment of severe injuries to the central nervous system (CNS), currently there are only few detailed preclinical studies linking cell fate with experimental outcome. In this study, we aimed to validate whether IV administration of allogeneic NSC can improve experimental autoimmune encephalomyelitis (EAE), a well-established animal model for human multiple sclerosis (MS). For this, we cultured adherently growing luciferase-expressing NSCs (NSC-Luc), which displayed a uniform morphology and expression profile of membrane and intracellular markers, and which displayed an in vitro differentiation potential into neurons and astrocytes. Following labeling with green fluorescent micron-sized iron oxide particles (f-MPIO-labeled NSC-Luc) or lentiviral transduction with the enhanced green fluorescent protein (eGFP) reporter gene (NSC-Luc/eGFP), cell implantation experiments demonstrated the intrinsic survival capacity of adherently cultured NSC in the CNS of syngeneic mice, as analyzed by real-time bioluminescence imaging (BLI), magnetic resonance imaging (MRI), and histological analysis. Next, EAE was induced in C57BL/6 mice followed by IV administration of NSC-Luc/eGFP at day 7 postinduction with or without daily immunosuppressive therapy (cyclosporine A, CsA). During a follow-up period of 20 days, the observed clinical benefit could be attributed solely to CsA treatment. In addition, histological analysis demonstrated the absence of NSC-Luc/eGFP at sites of neuroinflammation. In order to investigate the absence of therapeutic potential, BLI biodistribution analysis of IV-administered NSC-Luc/eGFP revealed cell retention in lung capillaries as soon as 1-min postinjection, resulting in massive inflammation and apoptosis in lung tissue. In summary, we conclude that IV administration of NSCs currently has limited or no therapeutic potential for neuroinflammatory disease in mice, and presumably also for human MS. However, given the fact that grafted NSCs have an intrinsic survival capacity in the CNS, their therapeutic exploitation should be further investigated, and-in contrast to several other reports-will most likely be highly complex.

Fibrous intimal thickening at implantation adversely affects long-term kidney allograft function.

BACKGROUND: Kidneys from marginal and older donors are increasingly used to respond to the increasing demand for kidney transplants. This study evaluated the predictive value of intimal hyperplasia, as a marker of vasculopathy, in the renal allograft at the time of transplantation (transplantation) on the subsequent graft function (7 years). METHODS: The intima/media ratio of the arterial walls (I/M) was morphometrically determined by the sectorial elliptic method, in 51 implantation biopsies. Two study groups were determined. Group 1, with I/M less than or equal to 0.47, was considered as the group with minimal vascular damage at transplantation. Group 2, with I/M more than 0.47, was considered as having vasculopathy at transplantation. RESULTS: During the first 15 months, the estimated glomerular filtration rate improved in group 1 from 53+/-17 to 61+/-17 mL/min/1.73 m2, whereas it decreased from 51+/-21 to 46+/-14 mL/min/1.73 m2 in group 2. From 1 year posttransplantation, the estimated glomerular filtration rate (eGFR) was significantly higher in group 1 at all time points (6 month evaluation). The difference in graft function between the two groups (mean, 11 mL/min/1.73 m2) remained unchanged between 1 and 7 years posttransplantation. Among several clinical parameters investigated, blood pressure of the recipient significantly modulates the impact of preexisting vasculopathy on graft function. CONCLUSION: Our data provide evidence that donor-related vasculopathy, at the time of transplantation, has a persistent significant impact on the subsequent graft function. This effect becomes only apparent at 1 year posttransplantation and is increased in recipients with inadequately controlled blood pressure.

Allogeneic stromal cell implantation in brain tissue leads to robust microglial activation.

Although adult and embryonic stem cell-based therapy for central nervous system (CNS) injury is being developed worldwide, less attention is given to the immunological aspects of allogeneic cell implantation in the CNS. The latter is of major importance because, from a practical point of view, future stem cell-based therapy for CNS injury will likely be performed using well-characterised allogeneic stem cell populations. In this study, we aimed to further describe the immunological mechanism leading to rejection of allogeneic bone marrow-derived stromal cells (BM-SC) after implantation in murine CNS. For this, we first investigated the impact of autologous and allogeneic BM-SC on microglia activation in vitro. Although the results indicate that both autologous and allogeneic BM-SC do not activate microglia themselves in vitro, they also do not inhibit activation of microglia after exogenous stimuli in vitro. Next, we investigated the impact of allogeneic BM-SC on microglia activation in vivo. In contrast to the in vitro observations, microglia become highly activated in vivo after implantation of allogeneic BM-SC in the CNS of immune-competent mice. Moreover, our results suggest that microglia, rather than T-cells, are the major contributors to allograft rejection in the CNS.

Reduced postischemic macrophage infiltration and interstitial fibrosis in osteopontin knockout mice.

BACKGROUND: Osteopontin (OPN) is a phosphoprotein that is up-regulated in several experimental models of renal disease, including ischemia/reperfusion injury. OPN has been described as a macrophage chemoattractant, may serve as a survival factor for tubular cells, and is implicated in the development of tubulointerstitial fibrosis. However, the precise role of this protein in renal pathophysiology remains unclear. METHODS: OPN knockout and wild-type mice were subjected to 30 minutes of warm renal ischemia combined with a contralateral nephrectomy, and sacrificed at six different time points, ranging from 12 hours to seven days after reperfusion. Besides functional and morphological parameters of postischemic acute renal failure (ARF), macrophage infiltration, apoptosis and expression of collagen types I and IV were investigated. RESULTS: Postischemic ARF in OPN knockouts and wild-types showed a similar course and severity, without significant differences in either functional or morphological disease parameters. However, macrophage infiltration was significantly diminished in OPN knockouts after five and seven days, in cortex as well as in the outer stripe of the outer medulla (OSOM). Furthermore, OPN knockout mice showed significantly enhanced apoptosis in the injury phase and significantly less collagen I and IV expression in the regeneration phase of postischemic ARF. CONCLUSIONS: There was no influence of OPN protein on the severity or course of functional impairment or morphological injury in the first seven days after an ischemic insult to the kidney. However, our results demonstrate that OPN favors macrophage recruitment to the postischemic kidney, inhibits apoptosis, and stimulates the development of renal fibrosis after an acute ischemic insult.

ICAM-1 expression and leukocyte accumulation in inner stripe of outer medulla in early phase of ischemic compared to HgCl2-induced ARF.

BACKGROUND: After ischemia/reperfusion (I/R), as well as after toxic insults, there is significant infiltration of leukocytes in the kidney. It is well known that antibodies against adhesion molecules [e.g., intercellular adhesion molecule-1 (ICAM-1)] protect the kidney against acute ischemic injury. In contrast, same antibody treatment did not protect the rat kidney against toxic acute renal failure (ARF) induced by HgCl2. Protection obtained by anti-adhesion treatment in I/R injury is an early phenomenon, since delaying the administration of anti-ICAM-1 for 8 hours did not protect the kidney anymore. The aim of this study was to compare the early ICAM-1 expression and leukocyte accumulation in different zones of ischemic and toxic injury. METHODS: Male Lewis rats were injected with HgCl2 (2 mg/kg, subcutaneously) or uninephrectomized Lewis rats were submitted to 30 degrees C warm ischemia (I/R injury). Rats were sacrificed at 2, 6, 12 and 24 hours. ICAM-1 (1A29) expression in kidney was evaluated morphometrically. Different subsets of leukocytes were stained by immunohistochemistry and counted in cortex, the outer stripe of the outer medulla (OSOM) and the level of the inner stripe of the outer medulla (ISOM). RESULTS: Although the functional and morphologic damage was comparable between the I/R and toxic ARF group, different ICAM-1 expression could be observed early after injury. ICAM-1 expression in the ISOM started already 2 hours after the onset of I/R injury, and was increased after 12 hours in the cortex and after 24 hours in the OSOM. In contrast, during the first 24 hours after injury, ICAM-1 expression in HgCl2-injured kidneys was not different from noninjured kidneys in the ISOM and the cortex, whereas in the OSOM, ICAM-1 expression increased. The number of polymononuclear cells (PMNs) was low in noninjured kidneys and did not increase in time after both I/R injury and after HgCl2-induced ARF. In the ISOM, significant monocyte and T-cell accumulation was observed early after I/R but not after HgCl2. There was no significant T-cell accumulation in the cortex or in the OSOM. CONCLUSION: After HgCl2, almost no leukocyte accumulation and up-regulation of ICAM-1 was observed the first 12 hours after injury. In contrast, very early after I/R injury, increased expression of ICAM-1 goes along with monocyte and T-cell accumulation in the ISOM, endorsing this particular zone as critical in renal I/R injury. These observations contribute to the understanding why anti-ICAM-1 treatment in acute I/R injury is successful, but fails in acute toxic injury induced by HgCl2.

Acute ischemia/reperfusion injury after isogeneic kidney transplantation is mitigated in a rat model of chronic renal failure.

The influence of chronic renal failure on renal susceptibility to an acute ischemic insult was evaluated. Recipient Lewis rats were randomly assigned to undergo 5/6 nephrectomy (chronic renal failure, CRF) or sham operation (normal renal function, NRF). After 11 weeks, normal kidneys of Lewis donor rats were transplanted in the recipients. The outcome of the isografts was assessed. Filtration capacity of the isografts in the CRF rats was preserved to approximately one-quarter of its normal capacity on the 1st day post-transplantation, whereas it fell to 0 in the NRF rats. This was reflected by a significantly higher increase in serum creatinine in the latter group. The isografts in the CRF rats had a significantly lower degree of acute tubular necrosis and no increase in the number of macrophages and T lymphocytes in the first 24 h in contrast to the NRF rats. Epithelial regeneration and repair started earlier in the CRF group. In conclusion, the present study indicated that CRF blunted ischemia/reperfusion injury of a transplanted kidney, and that its regeneration capacity was certainly not hampered by the presence of chronic uremia. These results will be the basis for studies on modulation of early leukocyte-endothelial interactions resulting from immunological disturbances inherent to the uremic environment.

T cells as mediators in renal ischemia/reperfusion injury.

Inflammation has been established to contribute substantially to the pathogenesis of ischemia/reperfusion (I/R) with a central role for particular cells, adhesion molecules, and cytokines. Until recently, most of the research trying to unravel the pathogenesis of I/R injury has been focused on the role of neutrophils. However, recent studies have brought evidence that T cells and macrophages are also important leukocyte mediators of renal and extrarenal (liver) I/R injury. In vivo depletion of CD4+ cells but not CD8+ cells in wild-type mice was protective in I/R of the kidney. A marked preservation of liver function was also found after I/R in T-cell deficient athymic mice. Blocking the b130/CD28 costimulatory pathway by CTLA-4 Ig (recombinant fusion protein) ameliorated renal dysfunction and decreased mononuclear cell infiltration in I/R of the kidney. b130-1 expression was found limited to the membrane of the endothelial cells of the ascending vasa recta, resulting in trapping of CD28-expressing CD4 T cells. This trapping of leukocytes results in the upstream congestion in the ascending arterial vasa recta, generating the since more than 150 years described medullary vascular congestion of the kidney soon after ischemic injury. It seems worthwhile to study a combination therapy using anti-inflammatory/anti-adhesion molecules in the early phase of I/R.

Effect of immunosuppression on damage, leukocyte infiltration, and regeneration after severe warm ischemia/reperfusion renal injury.

BACKGROUND: Post-ischemia/reperfusion (I/R) damage, accompanied by leukocyte infiltration, is unavoidable in renal transplantation, as is the need for immunosuppressive treatment. Influence of immunosuppressive treatment on post-I/R renal damage, nonalloimmune cellular infiltration, and regeneration is not well studied. METHODS: Uninephrectomized inbred LEW rats were submitted to warm renal ischemia of 45 minutes/60 minutes, and received different immunosuppressive regimens: cyclosporine (CsA) 10 mg/kg/day subcutaneously in the neck daily, or mycophenolate mofetil (MMF) 20 mg/kg/day by daily oral gavage. Control animals underwent sham operation (unilateral nephrectomy) with immunosuppressive treatment or ischemia with vehicle administration. In addition the effect of MMF/mycophenolic acid (MPA) on renal tubule cell proliferation in culture was studied with bromodeoxyuridine incorporation. RESULTS: The post-I/R interstitial cellular infiltration/proliferation consisted mainly of mononuclear leukocytes [first monocytes/macrophages (Mo/MPhi) followed by CD4+ cells]. This mononuclear cell infiltration became apparent 24 hours after injury at the time of acute tubular necrosis, and was most prominent during the phase of regeneration. Severe I/R combined with CsA aggravated morphologic damage and dysfunction, without effect on tubular cell proliferation and tubular regeneration. Early leukocyte infiltration was qualitatively and quantitatively comparable to control animals, yet decreased moderately later in time. In contrast, MMF in combination with severe I/R did not influence initial morphologic damage and dysfunction. Although the initial leukocyte infiltration was comparable to control animals, the subsequent mononuclear cell accumulation, especially CD4 T cells decreased dramatically during MMF treatment. This was concomitant with a decrease of tubular cell proliferation and hence tubular regeneration. Increasing MPA concentrations in renal tubular cell culture caused a significant decrease in total cell number, and an almost arrest of bromodeoxyuridine incorporation, as measurement of cell proliferation. CONCLUSION: Immunosuppressive treatment with CsA or MMF affected significantly and in a different manner post-I/R renal morphologic damage, interstitial leukocyte, accumulation and regeneration.

Decreased short-term renal graft survival in Maghrebian recipients.

The influence of race on renal allograft survival is disputed. We studied 16 cadaveric renal transplants in 14 Maghrebian patients, each matched with two controls of local origin. Patient survival at 12 months was 93% in the Maghreb group and 97% in the control group (NS). Graft survivals at 3 months for these two groups were 73% and 97%, respectively (P<0.01). At 6 months, graft survival in the control group remained unchanged at 97%, whereas in the case group it declined further to 59% (P<0.01). Overall graft failure in the Maghreb group amounted to 44% (seven of 16 transplants). In each case, failure was due to biopsy-proven acute rejection. Overall graft failure amongst the controls was only 6% (two of 32 transplants) (P=0.004) (only one case of acute rejection, or 3%) (P=0.01). This study provides evidence for significantly lower short-term renal graft survival in Maghrebian recipients of a Caucasian graft. Acute rejection seems to play a major causative role in graft loss in this group.