Impaired tubulointerstitial expression of endothelin-1 and nitric oxide isoforms in donor kidney biopsies with postischemic acute renal failure

BACKGROUND: About 30% of cadaveric renal allografts, but almost never living-donor kidneys, develop postischemic acute renal-transplant failure (ARF). We therefore quantified the expression of essential reperfusion regulators in different compartments of cadaveric and living-donor kidney biopsies. METHODS: Specimens were obtained from donor kidneys at the end of the cold ischemia time before implantation and categorized into three groups according to donor source and early posttransplant function. Ten living-donor biopsies (LIV) were compared with nine cadaveric kidney biopsies (CAD) with primary posttransplant function (CAD-PF) and to nine with ARF (CAD-ARF). Laser capture microdissection was used to isolate glomeruli from tubulointerstitium. The gene expression of intercellular adhesion molecule (ICAM)-1, interleukin (IL)-1beta, endothelin (ET)-1, inducible nitric oxide synthase (iNOS), and endothelial nitric oxide synthase (eNOS) was quantified in glomeruli and tubulointerstitium by real-time polymerase chain reaction (TaqMan). RESULTS: Tubulointerstitial areas of all CAD kidneys revealed significantly lower mRNA levels of all investigated genes compared with LIV. Tubulointerstitial ET-1, iNOS, and eNOS in CAD-ARF averaged only half of the expression in CAD-PF kidneys. ICAM-1 and IL-1beta mRNA concentrations were equal in CAD-PF and CAD-ARF. Glomerular expression of the investigated genes was equal in CAD and LIV kidneys with the exception of ICAM-1 and ET-1, which were two times higher in CAD-PF compared with LIV and CAD-ARF. CONCLUSION: These data suggest that CAD compared with LIV kidneys have an impaired expression of immune and vasoregulatory genes in the tubulointerstitium, which may represent reduced cellular vitality and capacity to adaptation. The observed further reduction of ET-1, iNOS, and eNOS expression in CAD-ARF might contribute to reperfusion injury and delayed allograft function.     

Expression of adhesion molecules and RANTES in kidney transplant from nonheart-beating donors

The main difference between cadaveric kidneys from donors with a heartbeat (HBD) and kidneys from nonheart-beating donors (NHBD) is related to warm ischemia/reperfusion time which constitutes an acute inflammatory process. On the contrary, brain death induces in HBD expression of pro-inflammatory adhesion molecules, making it important to evaluate this kind of molecules in both types of donors. Human renal biopsies from NHBD, HBD and normal kidneys (ischemia time = 0) were taken and frozen just before transplant. A semi-quantitative RT-PCR method was used to determine intracellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), lymphocyte function associated antigen (LFA-1), LFA-3, CD40, CD40 ligand (CD40L) and RANTES (regulated upon activation, normal T-cell expressed and secreted) gene expression. We have detected an elevated relative gene expression of ICAM-1, VCAM-1 and RANTES in NHBD biopsies compared with normal kidneys. In the case of RANTES, the gene expression from NHBD biopsies was higher than observed in HBD biopsies. The rest of genes were not augmented in any group. Preliminary data about early outcome of transplants indicates a correlation between pretransplant RANTES high gene expression levels and early post-transplant acute rejection. The gene expression of pro-inflammatory molecules like adhesion molecules and RANTES is augmented in kidneys from cadaveric NBD just before transplant. The expression is higher probably because of the prolonged warm ischemia period. A larger clinical study is necessary to clarify the effects of these variable expressions on the transplant outcome.     

Acute graft-versus-host disease in pancreas transplantation: a comparison of two case presentations and a review of the literature

As a complication of solid organ transplantation, acute graft-versus-host disease (GVHD) is most associated with small bowel and liver transplants. We present two cases of acute GVHD following pancreas transplantation. Case 1 was a 27-year-old female who underwent cadaveric pancreas transplant 9 months after a successful live donor kidney transplant. Case 2 was a 38-year-old male who received a simultaneous cadaveric pancreas and live donor kidney transplant. Both patients presented within 30 days of transplant with nonspecific symptoms. Rejection and infection were ruled out. Both subjects had progressive decline in mentation associated with pancytopenia and hyperbilirubinemia. Rash was not present until late in their hospital course. Skin biopsies demonstrated mixed chimerism with pancreas donor DNA diagnostic of GVHD. Acute GVHD is a rare, often fatal, complication of pancreas transplantation, and its presentation appears to differ from acute GVHD associated with stem cell transplantation.     

Prognostic significance of microvascular thrombosis in donor kidney allograft biopsies

BACKGROUND: With a continuing demand for donor kidneys for organ transplantation, it is important to understand the significance of pathologic findings in the donor organ before transplantation. Microvascular thrombosis is sometimes encountered in association with disseminated intravascular coagulation in the donor, and it is unclear whether this finding may affect immediate allograft function and long-term graft survival. To further elucidate this question, we examined our experience with microvascular thrombosis in donor biopsies in the kidney transplant program at our institution. METHODS: Donor kidney biopsies showing microvascular thrombosis were identified from consecutive donor biopsies in the Duke University Medical Center transplant file database between January 1, 1995 and December 31, 2000. These biopsies and all other kidney biopsies and specimens from the recipients of these kidneys thus identified were reviewed. Sections were stained using a variety of methods, including hematoxylin-eosin, periodic acid-Schiff, methenamine silver, and Masson trichrome methods. Clinical records of the transplant recipients of these kidneys were also reviewed to assess allograft performance and survival. RESULTS: From 230 consecutive donor kidney biopsies, we identified eight cases exhibiting donor-microvascular thrombosis. Mean follow-up times were 27.5 months for the thrombi group and 35 months for the non-thrombi group. Recipients of grafts with donor thrombi were more likely to exhibit delayed graft function, but graft function at 1 and 2 years and graft survival were similar between the two groups. Subsequent posttransplantation biopsies in five of eight cases showed no evidence of residual thrombosis. CONCLUSIONS: These data suggest that the presence of donor microvascular thrombosis does not portend poor outcome in renal transplantation.     

Cholesterol embolization in renal allografts

Renal cholesterol embolization (RCE) in native kidneys has a dismal outcome and frequently leads to irreversible renal failure. RCE may rarely occur in renal allografts as well, particularly if the recipient or the donor has prominent atherosclerosis. The natural history of RCE in renal transplants is unknown. We have reviewed the surgical pathology files of The Johns Hopkins Hospital in the 14-year period between 1984 and early 1999 and found 7 RCE cases among 1500 renal transplant biopsies (0.47%). One of the seven cases had three biopsies showing cholesterol emboli, the first of which was a postreperfusion (immediate posttransplant) biopsy. The probable source of the cholesterol emboli was the recipient in six cases and the donor in one case. Five donors were cadaveric and two were living donors. Six biopsies were taken within the first 4 months posttransplant (four were postreperfusion biopsies). One recent patient had the inciting event of arteriography and stent placement 2 years posttransplant and is currently doing well. One kidney failed due to posttransplant lymphoproliferative disorder (PTLD), another kidney failed with complicating opportunistic infections, and the other five were functioning 2 to 6 years posttransplant. A literature review revealed additional 14 RCE cases in renal transplants. Combining our cases with those in the literature (21 cases), reveals that the origin of the RCE was probably the recipient in 11 cases (seven cadaveric, two living-related, and two unknown), and the donor in 10 cases (eight cadaveric and two unknown). Graft failure occurred in two of the 11 cases, where RCE was of probable recipient origin. Seven of the 10 kidneys, where the RCE was probably of donor origin, failed due to allograft dysfunction; one of them also developed superimposed rejection and cytomegalovirus infection. We conclude that if RCE is originating in the recipient, graft survival is usually good. In contrast, if RCE is of donor origin, graft dysfunction and subsequent graft loss are common. The reason for this difference may be the more extensive RCE developing in an atherosclerotic cadaveric donor during organ procurement or severe trauma leading to death.     

Are wedge biopsies of cadaveric kidneys obtained at procurement reliable?

BACKGROUND: Single wedge biopsy of cadaveric kidneys from donors older than 55 is currently the standard method of evaluating their viability for transplantation. The degree of glomerulosclerosis presently determines whether a kidney can be transplanted, but most biopsies sample only the subcapsular region and may not accurately represent the true renal architecture. Our study evaluated the accuracy of transplant suitability determinations based upon the single wedge biopsy of cadaveric kidneys. METHODS: We took kidneys that were refused by UNOS centers on the basis of biopsy results, examined their histology in detail, and reviewed donor medical histories. Sections were taken from the upper, lower, and mid-portion of each kidney and stained with the periodic acid Schiff stain. Percentage and location of glomerulosclerosis and other relevant pathology were then determined in each section. We compared our findings with the results of the original wedge biopsies obtained at the time of procurement. RESULTS: Nine kidneys were obtained and examined. The wedge biopsies at the time of procurement showed glomerulosclerosis ranging from 8 to 36% (median 17%). The multiple kidney sections we analyzed showed fewer sclerosed glomeruli, ranging from 3 to 15% (median 7%, P<0.001), with most of the sclerosed glomeruli identified located in the immediate subcapsular region (P<0.001). CONCLUSIONS: Wedge biopsies of donor kidneys can overestimate the total amount of glomerulosclerosis, apparently because of a predominance of sclerosis in the kidney's subcapsular region, the area predominantly sampled by the usual wedge biopsy. These inappropriately high estimates of glomerulosclerosis can result in refusal of kidneys that might be suitable for transplantation.     

Waiting time on dialysis as the strongest modifiable risk factor for renal transplant outcomes: a paired donor kidney analysis

BACKGROUND: Waiting time on dialysis has been shown to be associated with worse outcomes after living and cadaveric transplantation. To validate and quantify end-stage renal disease (ESRD) time as an independent risk factor for kidney transplantation, we compared the outcome of paired donor kidneys, destined to patients who had ESRD more than 2 years compared to patients who had ESRD less than 6 months. METHODS: We analyzed data available from the U.S. Renal Data System database between 1988 and 1998 by Kaplan-Meier estimates and Cox proportional hazards models to quantify the effect of ESRD time on paired cadaveric kidneys and on all cadaveric kidneys compared to living-donated kidneys. RESULTS: Five- and 10-year unadjusted graft survival rates were significantly worse in paired kidney recipients who had undergone more than 24 months of dialysis (58% and 29%, respectively) compared to paired kidney recipients who had undergone less than 6 months of dialysis (78% and 63%, respectively; P<0.001 each). Ten-year overall adjusted graft survival for cadaveric transplants was 69% for preemptive transplants versus 39% for transplants after 24 months on dialysis. For living transplants, 10-year overall adjusted graft survival was 75% for preemptive transplants versus 49% for transplants after 24 month on dialysis. CONCLUSIONS: ESRD time is arguably the strongest independent modifiable risk factor for renal transplant outcomes. Part of the advantage of living-donor versus cadaveric-donor transplantation may be explained by waiting time. This effect is dominant enough that a cadaveric renal transplant recipient with an ESRD time less than 6 months has the equivalent graft survival of living donor transplant recipients who wait on dialysis for more than 2 years.     

The contribution of adhesion molecule expression in donor kidney biopsies to early allograft dysfunction.

BACKGROUND: Renal allograft rejection is associated with the expression of adhesion molecules on vascular endothelial and tubular epithelial cells. METHODS: To assess whether the number of cell adhesion molecules expressed in donor kidneys can predict early rejection or delayed graft function, kidney biopsies from 20 living and 53 cadaveric kidney donors were obtained before engraftment into the recipients and the expression of the cell adhesion molecules intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and endothelial leukocyte adhesion molecule (E-selectin) were determined by immunohistochemistry. RESULTS: All biopsies from living donors showed significantly lower expression of ICAM-1 and VCAM-1 compared to biopsies from cadaveric donors. There was no difference in the expression of adhesion molecules on tubular cells between transplants with primary function compared to allografts with early rejection in living donated kidneys (ICAM-1: 2+/-8 vs. 3+/-8%; VCAM-1: 9+/-7 vs. 1+/-1%), as well as in cadaveric kidneys (ICAM-1: 38+/-29 vs. 39+/-38%; VCAM-1: 55+/-27 vs. 48+/-29%). The expression of ICAM-1 molecules on tubular cells was determined to be a predictor for the occurrence of delayed graft function in cadaveric kidneys (ICAM-1: 65+/-24* vs. 38+/-29% delayed graft versus primary graft function). No delayed graft function occurred in recipients of living donated kidneys. CONCLUSIONS: These data suggest that adhesion molecule expression in donor biopsies is not a predictor for early allograft rejection, but can be used as a marker for the development of postischemic acute renal allograft failure.     

Transplanting Kidneys from Deceased Donors With Severe Acute Kidney Injury

Our aim was to determine outcomes with transplanting kidneys from deceased donors with acute kidney injury, defined as a donor with terminal serum creatinine ≥2.0 mg/dL, or a donor requiring acute renal replacement therapy. We included all patients who received deceased donor kidney transplant from June 2004 to October 2013. There were 162 AKI donor transplant recipients (21% of deceased donor transplants): 139 in the standard criteria donor (SCD) and 23 in the expanded criteria donor (ECD) cohort. 71% of the AKI donors had stage 3 (severe AKI), based on acute kidney injury network (AKIN) staging. Protocol biopsies were done at 1, 4, and 12 months posttransplant. One and four month formalin‐fixed paraffin embedded (FFPE) biopsies from 48 patients (24 AKI donors, 24 non‐AKI) underwent global gene expression profiling using DNA microarrays (96 arrays). DGF was more common in the AKI group but eGFR, graft survival at 1 year and proportion with IF/TA>2 at 1 year were similar for the two groups. At 1 month, there were 898 differentially expressed genes in the AKI group (p‐value <0.005; FDR <10%), but by 4 months there were no differences. Transplanting selected kidneys from deceased donors with AKI is safe and has excellent outcomes.     

Renal transplantations performed using non-heart-beating organ donors: going back to the future?

BACKGROUND: As more expanded-criteria organ donors are used to bridge the widening gap between organ supply and demand, non-heart-beating (NHB) donors will become increasingly important. The purpose of this study was to analyze renal transplant outcomes using this source of cadaveric (CAD) organs and compare the results with heart-beating organ sources. METHODS: Data from 98,698 adult CAD renal transplant recipients and 34,531 living donor renal transplant recipients registered in the U. S. Renal Data System database between January 1993 and June 2000 were analyzed. Kaplan-Meier survival curves were used to compare graft and patient survival rates between NHB, CAD, and living donor transplant recipients. Cox proportional hazards models were used to identify risk factors for NHB donor recipients, while adjusting for potential confounding variables. RESULTS: Recipients of NHB donor organs experienced nearly twice the incidence of delayed graft function (DGF) compared with heart-beating donors (42.4% vs. 23.3%, respectively). NHB donor transplants experienced comparable allograft survival when compared with CAD transplants at 6 years (73.2% vs. 72.5%, respectively; P=NS); patient survival was greater at 6 years for NHB compared with CAD renal transplant recipients (80.9% vs. 77.8%, respectively; P=NS). Significant factors for allograft loss for NHB donor organ recipients included the following: organ used for repeat transplants; DGF; donor age older than 35 years; and head trauma as a cause of initial injury (relative risk 2.74, 1.90, 1.78, and 1.41, respectively). CONCLUSIONS: Although exhibiting elevated DGF rates, allograft and patient survival rates of transplants from NHB donor sources are equivalent to those from conventional CAD sources. Donor age, recipient transplant number, female recipient, mechanism of injury, and DGF were the most pertinent variables leading to poor outcomes.     

Pediatric renal transplantation from related living donor

Living related donor (LRD) provides significant advantages when compared with cadaveric donor (CAD) in term of improved patient and graft survival and shorten waiting time. From 1985, 176 kidney transplants were performed at our Center. Of these, 156 (89%) were from CAD and 20 (11%) were from LRD, first degree. The purpose of this paper is to show our experience at 5 years with use of LRD. All donors underwent standardized metabolic workup, angiography assessed and renal function test. Twelve children received their first transplant and 8 were retransplant (6-second, 1-third and 1-fourth). Immunosuppressive therapy consisted of globulin antithymocyte, azathioprine, cyclosporine and prednisolone, using FK506 and mycophenolate mofetil in some of them. Four kidneys with multiple renal arteries were reconstructed ex vivo with microsurgical technique before transplantation. The most significant morbidity was due to FK506-associated thrombotic microangiopathy (TMA) with graft lost. All patients (donor and recipient) survived. Five years graft survival rate is 95% and mean glomerular filtration rate is 81.33 ml/min/1.73 m2.     

Cadaver versus living donor kidneys: impact of donor factors on antigen induction before transplantation.

BACKGROUND: It is widely recognized that living-related donor (LRD) renal allografts have a higher overall graft survival than cadaver donor transplants. We tested the hypothesis that part of this is attributable to LRD kidneys being obtained under optimal conditions from healthy donors, whereas cadaveric kidneys may have experienced injury as a result of inflammatory events around the time of brain death. METHODS: We have performed a comparative immunohistochemical analysis of pretransplant donor biopsies from cadaveric (N = 65) and LRD (N = 29) kidneys to determine any differences that may predispose them to subsequent damage. Cryostat sections were stained with antibodies to leukocytes, adhesion molecules, and human leukocyte antigen (HLA)-DR antigens, and the expression was assessed semiquantitatively. RESULTS: High levels of endothelial E-selectin and proximal tubular expression of HLA-DR antigens, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 were detected in biopsies from cadaveric kidneys, whereas expression of these markers was markedly reduced in LRD kidneys. High levels of tubular antigen expression were significantly associated with traumatic death, prolonged ventilation, and episodes of infection in cadaver donors. Furthermore, the expression of pretransplant tubular antigens in cadaver donor kidneys was significantly associated with early acute rejection following transplantation, suggesting that such kidneys are predisposed to subsequent immune-mediated attack following transplantation. CONCLUSIONS: These results may explain, in part, the superior outcome of LRD allografts compared with cadaver renal allografts.     

Gene expression and biomarkers in renal transplant ischemia reperfusion injury

The incidence of postischemic acute renal allograft failure (ARF) occurs in roughly 25% of cadaveric donor kidney recipients. This high rate remained virtually unchanged over the last decades despite modification in recipient management and modern immunosuppressive strategies. It has recently been shown that among other reasons, the systemic inflammation in the brain death cadaveric organ donor contributes to subsequent ARF in the recipient. This review focuses on the consequences of ischemia and reperfusion on the cellular level and offers potential solutions for the reduction of ARF. Genome-wide gene expression analysis together with sophisticated biostatistical analysis made it possible to identify several candidate gene products and proteins that may act as specific and sensitive biomarker for renal inflammation and ischemia. These markers may be very helpful in the clinical management of patients with a high a priori risk of subsequent ARF such as recipients of marginal donor kidneys. Ongoing clinical trials will evaluate whether immunosuppression of the cadaveric organ donor before organ harvest will have the potential to reduce inflammation in the transplant kidney and subsequently lead to a reduction in the rate of ARF.     

Transplantation of pediatric cadaveric kidneys into adult or pediatric recipients

In Japan, nationwide cadaveric organ sharing for kidney transplantation by the Japan Organ Transplant Network (JOTN) has operated since April 1995. This study retrospectively analyzed the long-term results of single pediatric donor kidneys transplanted into adult or pediatric recipients at a single center. From March 1983 to December 2002, 281 cadaveric renal allografts were transplanted at our center, including, 17 recipients of cadaveric kidneys from donors aged less than 16 years. We divided these 17 recipients into two groups: 10 adult recipients (group 1; G1) and seven pediatric recipients (group 2; G2). HLA-AB, -DR mismatches were 1.3 +/- 1.3, 0.7 +/- 0.5 in G1 and 2.6 +/- 1.3, 1.4 +/- 0.8 in G2, respectively (P < .05 for both). The end of the observation of this study was March 2003. Among G1, two recipients died with functioning grafts and one died after graft loss. Among G2, no recipients died. Patient survival rates at 1 and 5 years were 90% and 80% in G1 and 100% and 100% in G2, respectively. At the end of the observation in this study, five recipients among G1 and six recipients among G2 had functioning grafts. Graft survival rates at 1 and 5 years were 90% and 80% in G1 and 85.7% and 85.7% in G2, respectively. Our results demonstrate that transplantation of pediatric cadaveric kidneys into pediatric recipients was excellent compared to adult recipients in terms of survival. Priority to pediatric patients should be given especially in cases of pediatric donors.