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Background Half of surgically created arteriovenous fistulas (AVFs) require additional intervention to effectively support hemodialysis. Postoperative care and complications may affect clinical maturation. Study Design Hemodialysis Fistula Maturation (HFM) Study, a 7-center prospective cohort study. Setting & Participants 491 patients with single-stage AVFs who had neither thrombosis nor AVF intervention before a 6-week postoperative ultrasonographic examination and who required maintenance hemodialysis. Predictors Postoperative care processes and complications. Outcomes Attempted cannulation, successful cannulation, and unassisted and overall clinical maturation as defined by the HFM Study criteria. Results AVF cannulation was attempted in 443 of 491 (90.2%) participants and was eventually successful in 430 of these 443 (97.1%) participants. 263 of these 430 (61.2%) reached unassisted and 118 (27.4%) reached assisted AVF maturation (overall maturation, 381/430 [88.6%]). Attempted cannulation was less likely in patients of surgeons with policies for routine 2-week versus later-than-2-week first postoperative visits (OR, 0.21; 95% CI, 0.06-0.70), routine second postoperative follow-up visits (OR, 0.39; 95% CI, 0.15-0.97), and a routine clinical postoperative ultrasound (OR, 0.28; 95% CI, 0.14-0.55). Attempted cannulation was also less likely among patients undergoing procedures to assist maturation (OR, 0.51; 95% CI, 0.27-0.98). Unassisted maturation was more likely for patients treated in facilities with access coordinators (OR, 1.91; 95% CI, 1.17-3.12), but less likely after precannulation nonstudy ultrasounds (OR per ultrasound, 0.42 [95% CI, 0.26-0.68]) and initial unsuccessful cannulation attempts (OR per each additional attempt, 0.90 [95% CI, 0.83-0.98]). Overall maturation was less likely with infiltration before successful cannulation (OR, 0.44; 95% CI, 0.22-0.89). Among participants receiving maintenance hemodialysis before AVF surgery, unassisted and overall maturation were less likely with longer intervals from surgery to initial cannulation (ORs for each additional month of 0.81 [95% CI, 0.76-0.88] and 0.93 [95% CI, 0.89-0.98], respectively) and from initial to successful cannulation (ORs for each additional week of 0.87 [95% CI, 0.81-0.94] and 0.88 [95% CI, 0.83-0.94], respectively). Limitations Surgeons' management policies were assessed only by questionnaire at study onset. Most participants received upper-arm AVFs, planned 2-stage AVFs were excluded, and maturation time windows were imposed. Some care processes may have been missed and the observational design limits causal attribution. Conclusions Multiple processes of care and complications are associated with AVF maturation outcomes.

Although the arteriovenous fistula (AVF) is the preferred mode of dialysis vascular access, AVF maturation failure remains a huge clinical problem, often resulting in a prolonged duration of use of tunneled dialysis catheters. In contrast, polytetrafluoroethylene (PTFE) grafts do not suffer from early failure, but have significant problems with later stenosis and thrombosis. This review will initially summarize the pathology and pathogenesis of PTFE graft dysfunction and will then use this as a basis for describing some novel therapies, which may have the potential to reduce PTFE graft dysfunction. Finally, we will emphasize that the introduction of such therapies could be an important first step toward individualizing overall vascular access care.

Vascular calcification is present in arterial vessels used for dialysis vascular access creation prior to surgical creation. Calcification in the veins used to create a new vascular access has not previously been documented. The objective of this study was to describe the prevalence of venous calcification in samples collected at the time of vascular access creation. Sixty-seven vein samples were studied. A von Kossa stain was performed to quantify calcification. A semi-quantitative scoring system from 0 to 4+ was used to quantify the percentage positive area for calcification as a fraction of total area (0: 0; 1+: 1-10%; 2+: 11-25%; 3+: 26-50%; 4+: >50% positive). Twenty-two of 67 (33%) samples showed evidence of venous calcification. Histologic examination showed varying degrees of calcification within each cell layer. Among the subset of patients with calcification, 4/22 (18%), 19/22 (86%), 22/22 (100%), and 7/22 (32%) had calcification present within the endothelium, intima, media, and adventitia, respectively. The mean semi-quantitative scores of the 22 samples with calcification were 0.18 ± 0.08, 1.2 ± 0.14, 1.6 ± 0.13, and 0.36 ± 0.12 for the endothelium, intima, media, and adventitia, respectively. Our results demonstrate that vascular calcification is present within veins used to create new dialysis vascular access, and located predominately within the neointimal and medial layers.

Summary Background and objectives New arteriovenous fistulas (AVF) are frequently unsuitable for hemodialysis because of AVF nonmaturation. Aggressive endovascular or surgical interventions are often undertaken to salvage nonmaturing AVFs. The effect of early interventions to promote AVF maturation on subsequent long-term AVF outcomes is unknown. Design, setting, participants, & measurements We evaluated 173 hemodialysis patients from two academic centers who received a new AVF. Of these, 96 (56%) required no further intervention, 54 (31%) required one intervention, and 23 (13%) required two or more interventions to achieve suitability for dialysis. We calculated AVF survival and frequency of postmaturation interventions in each group. Results Cumulative AVF survival (access cannulation to permanent failure) in patients with two or more versus one versus zero interventions before maturation was 68% versus 78% versus 92% at 1 year, 57% versus 71% versus 85% at 2 years, and 42% versus 57% versus 75% at 3 years. Using Cox regression analysis with interventions before maturation, age, sex, race, diabetes, peripheral vascular disease, access site, and obesity in the model, intervention before maturation (two or more) was the only factor associated with cumulative AVF survival. The number of interventions required to maintain patency after maturation was 3.51 ± 2.20 versus 1.37 ± 0.31 versus 0.76 ± 0.10 per year in patients with two or more versus one versus zero interventions before maturation. Conclusions Compared with AVF that mature without interventions, AVF that require interventions have decreased cumulative survival and require more interventions to maintain their patency for hemodialysis.

Background. Venous neointimal hyperplasia is the most common cause of arteriovenous (AV) fistula and graft dysfunction following dialysis access surgery. However, the pathogenetic impact of pre-existing venous neointimal hyperplasia at the time of AV access creation on final clinical success is currently unknown in the setting of advanced chronic kidney disease (CKD) and end-stage renal disease (ESRD) patients. The aim of this study was to perform a detailed histological, morphometric, and immunohistochemical analysis of vein specimens in advanced CKD and ESRD patients collected at the time of new vascular access placement. Methods. Vein samples from 12 patients were collected at the time of AV access creation near the site of AV anastomosis. Histological, immunohistochemistry and morphometric studies were performed on these vein samples. Results. Examination of the tissue specimens obtained at the time of surgery showed neointimal hyperplasia in 10 of 12 specimens, ranging from minimal to very severe. The majority of cells within the neointima were myofibroblasts with a minority of contractile smooth muscle cells present. Conclusion. Our work represents a detailed description of the morphometric and cellular phenotypic lesions present in the veins of CKD and ESRD patients, prior to dialysis access placement. These studies (i) suggest the future possibility of a new predictive marker (pre-existing venous neointimal hyperplasia) for AV dialysis access dysfunction and (ii) open the door for the future development of novel local therapies for optimization of the venous substrate on which the dialysis access is created.

Purpose Although arteriovenous fistulae (AVFs) are currently the preferred mode of permanent hemodialysis access they do have significant problems due to initial non-maturation and a later venous stenosis. These problems appear to have been exacerbated following a push to increase AVF prevalence in the US. The reasons for both AVF non-maturation and the later venous stenoses are unclear but are thought to be related to abnormal hemodynamic wall shear stress (WSS) profiles. This technical note aims to describe the successful development of measurement techniques that can be used to establish a complete hemodynamic profile in a pig model with two different configurations of AVF. Methods and results The curved and straight AVF configurations were created in an in vivo pig model. Flow and pressure in the AVFs were measured using the perivascular flow probes and Doppler flow wires while the pressure was recorded using a pressure transducer. The anatomical configuration was obtained using two different approaches: a) combination of intravascular ultrasound (IVUS) and angiograms, (b) 64 slice CT angiography. 3D models were reconstructed using image processing and computer modeling techniques. Numerical calculations were then performed by applying the measured flow and pressure data into the configurations to obtain the hemodynamic WSS profiles. Conclusion The described methodologies will allow the calculation and optimization of WSS profiles in animal models. This information could then be translated to the clinical setting where it would have a positive impact on improving the early maturation rates of AVFs as well as reducing the late venous stenoses.

Summary Steroids and calcineurin inhibitors (CNI) have been mainstays of immunosuppression but both have numerous side effects that are associated with substantial morbidity and mortality. This study was carried out to determine if steroids can be eliminated with early discontinuation of cyclosporine A (CsA) and later discontinuation of mycophenolate mofetil (MMF). Ninety-six patients with kidney transplants were entered into four subgroups of two pilot studies. All patients received Thymoglobulin® induction, rapamycin (RAPA), and the immunonutrients arginine and an oil containing ω-3 fatty acids. Mycophenolate mofetil was started in standard doses and discontinued by 2 years. CsA was given in reduced doses for either 4, 6, or 12 months. Follow-up was 12–36 months. Thirteen first rejection episodes occurred during the first year (14%). Combining all patients, 86% were rejection-free at 1 year, 80% at 2 years and 79% at 3 years. No kidney has been lost to acute rejection. Ninety percent of the 84 patients at risk at the end of the study were steroid-free and 87% were off CNI. Fifty-seven percent of 54 patients with a functioning kidney at 3 years were receiving monotherapy with RAPA. We conclude that this therapeutic strategy is worthy of a prospective multi-center clinical trial.

This article (1) identifies the types of hemodialysis access, (2) summarizes the clinical standard of care for dialysis access grafts and fistulae, (3) describes the pathology and pathogenesis of venous stenosis in dialysis access grafts and fistulae, (4) tabulates avail-able therapies for hemodialysis vascular access dysfunction and speculates on the rea-sons for the lack of effective therapies, and (5) discusses the development and application of novel therapeutic interventions for this difficult clinical problem. The possibility that dialysis access grafts and fistulae could be the ideal clinical model for testing novel local therapies to block neointimal hyperplasia is discussed.

Hemodialysis vascular access dysfunction is a major cause of morbidity in the hemodialysis population and contributes significantly to the overall cost of end-stage renal disease programs. At a histological level, most hemodialysis vascular access dysfunction (in both native arteriovenous fistulae and PTFE dialysis access grafts) is due to venous stenosis and thrombosis, secondary to venous neointimal hyperplasia. However, despite a wealth of experimental and clinical data on the use of novel therapeutic interventions that target neointimal hyperplasia in the setting of coronary artery disease, there are unfortunately no effective therapeutic interventions for hemodialysis vascular access dysfunction at the present time. This is particularly unfortunate, since neointimal hyperplasia in the setting of hemodialysis vascular access fistulae and grafts could be the ideal clinical model to test novel therapeutic interventions for neointimal hyperplasia.

Arteriovenous fistula (AVF) maturation continues to cause significant morbidity and mortality. Despite the magnitude of the clinical problem, however, there are no effective clinical or biological predictors of AVF success or failure. Caroli et al. describe an innovative technology that may be successful in predicting AVF flow and diameter using standard-of-care preoperative inputs. Pending additional longer-term validation, the use of this technology could help us get the right access into the right patient at the right time.

The benefits of laparoscopic living-donor nephrectomy (LDN) are well described, while similar data on hand-assisted laparoscopic living-donor nephrectomy (HALDN) are lacking. We compare hand-assisted laparoscopic living-donor nephrectomy with open donor nephrectomy. One hundred consecutive hand-assisted laparoscopic living-donor nephrectomy (10/98-8/01) donor/recipient pairs were compared to 50 open donor nephrectomy pairs (8/97-1/00). Mean donor weights were similar (179.6 +/- 40.8 vs. 167.4 +/- 30.3 lb; p = NS), while donor age was greater among hand-assisted laparoscopic living-donor nephrectomy (38.2 +/- 9.5 vs. 31.2 +/- 7.8 year; p0.01). Right nephrectomies was fewer in hand-assisted laparoscopic living-donor nephrectomy [17/100 (17%) vs. 22/50 (44%); p0.05]. Operative time for hand-assisted laparoscopic living-donor nephrectomy (3.9 +/- 0.7 vs. 2.9 +/- 0.5 h; p0.01) was longer; however, return to diet (6.9 +/- 2.8 vs. 25.6 +/- 6.1 h; p0.01), narcotics requirement (17.9 +/- 6.3 vs. 56.3 +/- 6.4h; p0.01) and length of stay (51.7 +/- 22.2 vs. 129.6 +/- 65.7 h; p0.01) were less than open donor nephrectomy. Costs were similar ($11072 vs. 10840). Graft function and 1-week Cr of 1.4 +/- 0.9 vs. 1.6 +/- 1.1 g/dL (p = NS) were similar. With the introduction of HALDN, our laparoscopic living-donor nephrectomy program has increased by 20%. Thus, similar to traditional laparoscopic donor nephrectomy, hand-assisted laparoscopic living-donor nephrectomy provides advantages over open donor nephrectomy without increasing costs.

Arteriovenous fistula (AVF) stenosis remains an important cause of AVF maturation failure for which there are currently no effective therapies. To understand the mechanisms involved, we have examined the pattern of cellular proliferation at different time points in a pig model of AVF stenosis. Immunohistochemical analysis of cellular proliferation was performed at 2, 7, 28, and 42 days. The distribution of cellular proliferation within the different layers of the vessel wall was also studied. An ANOVA analysis was used to identify differences between the magnitude of cellular proliferation at different time points and within different layers of the vessel wall. Adventitial proliferation occurred at 2 days and declined over time. Intimal and medial proliferation peaked at 7 days and then decreased over time. There was minimal proliferation in all three layers at the 28- and 42-day time points. An important finding was the presence of active myofibroblast proliferation within "neointimal buds" at the 7-day time point. Results suggest that there could be early adventitial activation, followed by a passage of these cells into the medial and intimal layers. These suggest that the application of perivascular antiproliferative (adventitial) therapies at the time of surgery could potentially reduce AVF maturation failure.

Background. Beginning in 1984, all pancreas transplantations performed in the state of Ohio have been tracked by the Ohio Solid Organ Transplantation Consortium (OSOTC). In this study the outcomes of these transplantations were compared across 3 eras to determine whether increasing experience has been beneficial. Methods. Between July 1984 and December 1999, 765 kidney-pancreas (KPTx) and 76 pancreas only (Ptx) transplantations were performed. Outcomes measures for these 841 pancreas transplantations were compared over 3 eras, 1984 to 1989, 1990 to 1994, and 1995 to 1999. Results. One-year patient survivals for KPTx patients were 87%, 92%, and 94% in the 3 eras, respectively. Graft survival at 1 year was also markedly improved between era 1 and era 3, increasing for PTx patients from 21% to 85% and for KPTx patients from 68% to 85%. Average waiting time increased from 132 to 318 days between era 1 and era 3. Conversely, average length of stay in hospital was significantly decreased from 34 to 18 days. The cost of the procedure, as measured by hospital charges, also decreased when compared in 1985 dollars as a technique to control for inflation. Conclusions. These data suggest that pancreas transplantation in Ohio has become a very successful and cost-effective therapeutic intervention for patients with type I diabetes with or without concomitant end-stage renal failure. (Surgery 2001;130:546-53.)

Venous stenosis, secondary to venous neointimal hyperplasia (VNH), at the arteriovenous anastomosis (AV) is a major etiology of vascular access failure in AV fistulas (AVF) and AV grafts (AVG). Recently, our group has reported that severe VNH also occurs prior to vascular access placement. The objective of this study was to perform a comparison of the cellular phenotypes within the neointima from veins collected from subjects at the time of new vascular access creation and stenotic veins from subjects with failed AVGs and AVFs. Vein samples, collected at the time of new access surgery, and stenotic vein segments, collected at access revision, were evaluated for expression of α-smooth muscle actin (SMA), vimentin, and desmin within the neointima, and quantified using semiquantitative scoring. Within the neointima, the majority of cells from vein samples collected at the time of new access surgery were contractile smooth muscle cells, and veins from stenotic AVF and AVG were predominately myofibroblasts. Our results suggest the possibility of different mechanistic pathways in response to vascular injury that occurs prior to vascular access creation vs. after access creation, and that divergent therapeutic approaches may be needed for treating vascular injury in these two settings.

Purpose Venous stenosis secondary to neointimal hyperplasia is a major etiology of early arteriovenous fistula (AVF) failure. The natural history of AVF failure is likely influenced by progressive vascular insults to the vein prior to and after AVF creation. The main objectives of this study were to ( 1 ) provide a histologic and morphometric description of non-chronic kidney disease (CKD), upper extremity vein specimens and ( 2 ) perform a morphometric analysis to study venous histology from non-CKD upper extremity veins, veins collected at the time of new vascular access surgery and veins collected from failed stenotic AVFs. Methods Vein samples from 11 non-CKD deceased donors, 29 subjects receiving new vascular access creation and 20 subjects with stenotic failed AVFs were collected for histologic and morphometric analysis. Results The mean values of average intima/media thickness ± S.E. from veins collected from non-CKD subjects, subjects receiving new vascular access and subjects with stenotic AVFs were 0.16±0.02, 0.43±0.07 and 3.84±0.55, respectively (pConclusions Our results demonstrate a progressively increasing venous neointimal hyperplasia development from the non-CKD period through the period of AVF creation and failure. Vascular injuries from complications of progressive CKD prior to access placement and vascular injuries after vascular access placement may play important roles in these progressive vascular changes, and need to be further elucidated.

Purpose Arteriovenous fistula non-maturation because of a peri-anastomotic venous stenosis is currently a huge clinical problem for which there are no effective therapies. Methods In an attempt to further define the cellular pathways involved in this process we have assessed the pattern and intensity of macrophage infiltration at different time points in a pig model of AVF stenosis. Results Our results demonstrate an early and eccentric pattern of macrophage infiltration at 2d with a rapid disappearance of this infiltrate by 7d. Conclusion We suggest that this early and eccentric macrophage infiltration could play an important role in the pathogenesis of AVF non-maturation.

Arteriovenous fistula (AVF) maturation failure is currently a huge clinical problem. One approach to enhance the AVF maturation rate is an aggressive sequence of balloon angioplasty procedures, often known as balloon-assisted maturation. The goal of the current paper is to explore the pros and cons of this procedure and to try and better identify its impact on AVF maturation.

Although the arteriovenous fistula (AVF) is the preferred mode of dialysis vascular access, AVF maturation failure remains a huge clinical problem, often resulting in a prolonged duration of use of tunneled dialysis catheters. In contrast, polytetrafluoroethylene (PTFE) grafts do not suffer from early failure, but have significant problems with later stenosis and thrombosis. This review will initially summarize the pathology and pathogenesis of PTFE graft dysfunction and will then use this as a basis for describing some novel therapies, which may have the potential to reduce PTFE graft dysfunction. Finally, we will emphasize that the introduction of such therapies could be an important first step toward individualizing overall vascular access care.

Vascular calcification is present in arterial vessels used for dialysis vascular access creation prior to surgical creation. Calcification in the veins used to create a new vascular access has not previously been documented. The objective of this study was to describe the prevalence of venous calcification in samples collected at the time of vascular access creation. Sixty-seven vein samples were studied. A von Kossa stain was performed to quantify calcification. A semi-quantitative scoring system from 0 to 4+ was used to quantify the percentage positive area for calcification as a fraction of total area (0: 0; 1+: 1-10%; 2+: 11-25%; 3+: 26-50%; 4+:50% positive). Twenty-two of 67 (33%) samples showed evidence of venous calcification. Histologic examination showed varying degrees of calcification within each cell layer. Among the subset of patients with calcification, 4/22 (18%), 19/22 (86%), 22/22 (100%), and 7/22 (32%) had calcification present within the endothelium, intima, media, and adventitia, respectively. The mean semi-quantitative scores of the 22 samples with calcification were 0.18 ± 0.08, 1.2 ± 0.14, 1.6 ± 0.13, and 0.36 ± 0.12 for the endothelium, intima, media, and adventitia, respectively. Our results demonstrate that vascular calcification is present within veins used to create new dialysis vascular access, and located predominately within the neointimal and medial layers.

Purpose The aim of this study was to identify the effects of external beam radiation on PTFE dialysis graft dysfunction. Methods Seven patients who underwent PTFE dialysis graft angioplasty were randomized to receive either two 8 Gy doses of external beam radiation or no radiation. The primary endpoint was time to graft thrombosis with a secondary endpoint of time to first intervention. Results There was no statistically significant difference between the two groups in either of the endpoints, although grafts in the radiation group had a shorter time to thrombosis or intervention. Conclusions Our results demonstrate technical feasibility for use of external beam radiation in the setting of dialysis vascular access graft dysfunction. Larger randomized studies are required to identify whether there is a clinical benefit from this intervention.

A prospective randomized preliminary trial was performed in patients undergoing cadaveric renal transplantation to determine the potential benefits, disadvantages, and logistic problems associated with the administration of donor-specific transfusions and cyclosporine initiated 24 hr before transplantation. Ten patients received DST followed by continuous intravenous CsA approximately 24 hr before cadaveric renal transplantation from the same donor. Twelve patients receiving sequential therapy with Minnesota antilymphoblast globulin, azathioprine, and steroids with subsequent conversion to CsA served as controls. Patient demographics and the donor characteristics were evenly matched in the two groups. While the study group had longer cold ischemia time and more evidence of renal dysfunction within the first two weeks, subsequent renal function was identical in the groups and there were fewer episodes of severe rejection requiring treatment with OKT3 within the first six months in the DST group (5 vs. 0, P less than 0.05), which also had less reactivity in mixed lymphocyte cultures against preserved donor-specific lymphocytes than did the control group (stimulation index 9.0 +/- 3.0 vs. 25.3 +/- 6.0, respectively, P less than 0.05). The need for dialysis, incidence of infections and other complications, and subsequent immunosuppressive therapy were not different in the two groups. It is concluded that DSTs and intravenous CsA initiated 24 hr prior to transplantation are capable of inducing reduced immunologic responsiveness against the specific donor. Patients treated with this therapy should receive organs from "ideal" donors without risk factors and cold ischemia time should not exceed 30 hr. Further clinical studies of this approach are warranted.

Forty-four cadaver renal allograft recipients who had flowcytometric cross-match (FCXM) testing and sequential quadruple immunosuppression were studied with respect to the number of rejection episodes and the functional viability of the graft in the first year after transplantation. Fourteen of these patients had antibodies to donor T cells by FCXM. All were negative by conventional crossmatch. Multiple-regression analysis with HLA mismatches, panel-reactive antibody (PRA) percentage, flowcytometric channel shifts and transplant number as independent variables revealed that transplant number and high PRA (50%) impacted (p0.05) on serum creatinine at 1 month and 1 year, and graft survival at 1 year. In first transplants, a positive FCXM had no impact on 1-year graft survival rates; however, in retransplants, a positive FCXM and/or high PRA had a significant negative impact on 1-year graft survival. This study indicates that the FCXM should be utilized for retransplant patients, and in patients with a high PRA, in an attempt to improve graft survival for these high-risk recipients.

Background. Haemodialysis vascular access dysfunction (due to venous stenosis and thrombosis) is a leading cause of hospitalization and morbidity. The aim of the current study was to identify the specific cell types present within stenotic tissue samples from patients with AV fistula and graft failure. Methods. Discarded tissue segments were collected from the stenotic portions (usually near the graft-vein anastomosis or the AV anastomosis) of 23 dialysis grafts and 20 AV fistulae, and examined for expression of smooth muscle alpha actin, desmin, vimentin and a macrophage marker. Results. The majority of cells within the venous neointima (both grafts and fistulae) were myofibroblasts, with a smaller number of desmin positive smooth muscle cells. The graft neointima had a similar cellular phenotype, albeit without any desmin positive contractile smooth muscle cells. The majority of cells within the PTFE graft material were macrophages. Analysis of sequential sections revealed the presence of fibroblasts within the venous neointima and intragraft region. Conclusions. Our results demonstrate that contractile smooth muscle cells, myofibroblasts, fibroblasts and macrophages all play a role in the pathogenesis of dialysis access dysfunction (grafts and fistulae). Targeting these specific cell types might result in the development of novel therapeutic paradigms for haemodialysis vascular access dysfunction.

Elimination of corticosteroid-related morbidity has been a goal of transplant clinicians from the earliest days of renal transplantation more than 50 years ago. Over the past decade, this goal has begun to be realized. Herein, we describe our efforts to eliminate corticosteroid therapy from maintenance immunosuppression-efforts that have spanned 15 years and have included design and conduct of five multicenter trials and over ten single center trials with over 650 patients at the University of Cincinnati. These efforts have led to a near complete elimination of corticosteroid-related morbidity, and, importantly, a more precise definition of the risk/benefit assessments of corticosteroid withdrawal in individual patient populations, which has allowed individualization and tailoring of corticosteroid-free immunosuppression.

The purpose of this study was to define risk factors for acute rejection with early corticosteroid withdrawal (CSWD; within 7 days posttransplant) in renal transplantation. Data from prospective, IRB-approved early CSWD trials were analyzed. Overall acute rejection rate in 308 patients was 17.1%. Acute rejection rates and observed risks (OR) in patients with individual risk factors were: repeat transplants 38.6%; current PRA >25%; 29.4%; African Americans 23.5%; delayed graft function (DGF) 26.1%; HLA DR mismatches >0 17.9%; female gender 19.7%; Thymoglobulin induction 15.3%; type 1 diabetes 30.8%; type 2 diabetes 11.1%; deceased donor recipients 21%; and living donor recipients 14%. Logistic regression analysis provided the following risks (OR) for acute rejection: repeat transplant 2.51; current PRA > 25% 1.53; African Americans 1.47; DGF 1.58; HLA DR mismatches > 0 1.61; female gender 1.43; Thymoglobulin induction 0.61; type 1 diabetes 2.23, type 2 diabetes 0.5, deceased donor recipients 1.11, and living donor recipients 0.9. Risk factors for acute rejection under early corticosteroid withdrawal are similar to those previously defined under chronic corticosteroid therapy. These observations provide implications for future CSWD trials including: use of T cell depleting antibody induction therapy (thymoglobulin) to reduce acute rejection risk, 2) enrollment stratification for high risk groups, and 3) modified immunosuppression for high risk groups.

Weight gain is a known complication of corticosteroid maintenance therapy. The purpose of the present study was to compare patterns of weight gain under chronic corticosteroid therapy (CCST) with that observed under early (i.e., within 7 days posttransplant) corticosteroid withdrawal (CSWD) in renal-transplant recipients.Renal-transplant recipients who underwent early CSWD under four prospective, institutional review board-approved clinical trials were compared with a historic control group of patients receiving maintenance CCST.One hundred sixty-nine patients with early CSWD were compared with 132 patients who received CCST. Mean population weight gain was significantly higher in CCST patients at 3, 6, and 12 months posttransplant. Race influenced weight gain because white CSWD patients demonstrated greater reductions in weight gain compared with African-American patients. Sex also influenced weight gain: women demonstrated a greater benefit from CSWD than did men. Corticosteroid rejection therapy in CSWD patients completely restored weight gain because these patients showed weight gains similar to the CCST group. Finally, pretransplant body mass index (BMI) also influenced weight gain because patients who were overweight (BMI 25-30) or obese (BMI30) demonstrated a greater reduction in weight gain with CSWD than did patients of normal weight (BMI25).Early CSWD minimizes weight gain in renal-transplant recipients. Women, whites, and patients with high pretransplant BMI had greater reductions in weight gain with early CSWD.

Background Animal studies have shown that dietary supplementation with arginine and lipids containing the omega-3 and omega-9 fatty acids prolong allograft survival in animals receiving a short course of low-dose cyclosporine. They also reduce cardiovascular complications and infections in humans. Methods Adult renal transplant patients receiving standard immunosuppression were stratified according to gender, diabetic state, donor source (LD or CD), and first versus repeat transplant, and randomized to receive or not receive supplemental arginine and canola oil (containing both omega-3 and omega-9 fatty acids) twice daily. Patients were followed for a minimum of 3 years. Results Seventy-six patients were randomized to the supplement group (S) and 71 patients to the control group (C). Intent-to-treat analysis revealed that S patients had fewer post-30 day first rejection episodes (5.4%) when compared with the C group (23.7%) (P=0.01) and fewer post-30 day episodes of calcineurin inhibitor (CNI) drug toxicity (9.2% vs. 35.3%, P=0.003). S patients developed new onset diabetes mellitus (NODM) less frequently by 3 years (2.3% vs. 14.5%, P=0.04), had fewer cardiac events (5.0% vs. 17.1%, P=0.05), and fewer episodes of sepsis (6.5% vs. 18.7%, P=0.05). Conclusions Dietary supplementation with L-arginine and canola oil is a safe, inexpensive, and unique treatment, which is associated with decreased rejection rates and CNI toxicity after the first month in renal transplant patients. Due to reductions in NODM and cardiac events, long-term benefits for patient survival may be particularly important.

Background: Few studies have compared the quality of life (QoL) and functional recuperation of laproscopic donor nephrectomy (LDN) vs. open donor nephrectomy (ODN) donors. This study utilized the SF-36 health survey, single-item health-related quality of life (HRQOL) score, and a functional assessment questionnaire (‘Donor Survey’). Methods: Questionnaires were sent to 100 LDN and 50 ODN donors. These donors were patients whose procedures were performed at The University Hospital and The Christ Hospital in Cincinnati, Ohio. Results: A total of 46 (46%) LDN and 21 (42%) ODN donors returned the completed surveys. The demographics of the two groups were similar. LDN patients reported a more rapid return to 100% normal health (69 vs. 116 d; p = 0.24), part-time work (21.9 vs. 23.2 d; p = 0.09), and necessitated fewer physician office visits post-operative (2.8 vs. 4.4; p = 0.01). ODN patients reported shorter duration of oral pain medication use (13.4 vs. 7.2 d; p = 0.02). However, a greater number of ODN patients reported post-surgical chronic pain (3 vs. 6; p

African-Americans (AAs) have historically been considered high-risk renal transplant recipients due to increased rejection rates and reduced long-term graft survival. As a result, AAs are often excluded from corticosteroid withdrawal (CSWD) protocols. Modern immunosuppression has reduced rejections and improved graft survival in AAs and may allow successful CSWD. Outcomes in 56 AAs were compared to 56 non-AAs. All patients were enrolled in one of four early CSWD protocols. Results are reported as AA versus non-AA. Acute rejection at 1-year was 23% and 18%; (p = NS); creatinine clearance at 1-year was 75 versus 80 mL/min (p = NS); patient and graft survival was 96% versus 98% and 91% versus 91%; (p = NS). AAs benefit from early CSWD with significantly improved blood pressure, LDL130 mg/dL and HDL45 mg/dL at 1-year, post-transplant diabetes of 8.7%, and mean weight change at 1-year of 4.8 +/- 7.2 kg. In conclusion, early CSWD in AAs is associated with acceptable rejection rates, excellent patient and graft survival, and improved cardiovascular risk, indicating that the risks and benefits of early CSWD are similar between AAs and non-AAs. Additional follow-up is needed to determine long-term renal function, graft survival, and cardiovascular risk in AAs with early CSWD.

Although venous valves have been implicated in the pathogenesis of discrete stenoses associated with dialysis vascular access dysfunction, especially in the context of cephalic arch stenosis,1 there is no documentation on (a) the histological presence or absence of valves in patients with dialysis access dysfunction, (b) the presence or lack of hypertrophy within these valves that are exposed to high flows, and (c) the cellular phenotype of venous valves in the context of dialysis access dysfunction. The images shown will attempt to provide answers to these questions (Figures 1 and 2).2, 3, 4

Hemodialysis vascular access dysfunction is a major cause of morbidity and hospitalization in the hemodialysis population at a cost of over 1 billion dollars per annum. Venous stenosis and thrombosis as a result of venous neointimal hyperplasia are the major causes of hemodialysis vascular access dysfunction. Despite the magnitude of the clinical problem, there are currently no effective therapies for this condition. We believe that this could be because of an inadequate understanding of the pathogenesis of this condition. At a histological level, venous neointimal hyperplasia (both in human specimens and in a pig model) is characterized by the presence of smooth muscle cells/myofibroblasts, microvessel formation (angiogenesis), and the accumulation of extracellular matrix components, all of which could be potential targets for therapeutic intervention. In particular, polytetrafluoroethylene dialysis access grafts could be the ideal clinical model for testing out novel local therapies to block neointimal hyperplasia. The current review describes the lesion of venous neointimal hyperplasia in human samples and in a pig model and suggests possible future directions for the development of effective local therapies for this condition.

c Atheroembolic disease is a known cause of renal failure following invasive vascular procedures in patients with atherosclerosis. It is, however, not generally associated with renal transplant dysfunction. We report on a case of donor-transmitted atheroembolic renal disease, which led to an immediate loss of the transplant kidney in the operating room. Risk factors associated with this condition and methods to prevent this complication are discussed. © 2001 by the National Kidney Foundation, Inc.

Introduction The purpose of this study was to determine whether incidentally discovered, small renal cell cancers (RCC) in donor kidneys can be excised and safely transplanted. Methods The Israel Penn International Transplant Tumor Registry database was searched and all small RCC that were identified and resected prior to transplantation of deceased and living donor kidneys were reviewed. Patient demographics, tumor characteristics, recurrence, and survival were examined. Results Fourteen kidneys were identified in which small RCC were noted at the time of procurement and where the tumors were excised ex vivo and then transplanted. Eleven kidneys were obtained from living related donors and three were from deceased donors. Median tumor size was 2 cm (range 0.5 to 4 cm). All 14 tumors were of histological Furhman grade II/VI ( n = 8) or Furhman grade I/VI ( n = 6). All kidneys had pathologically confirmed negative margins. The mean age of the recipients was 40.8 ± 9.2 years, with the majority being men (11 men; 3 women). Median follow-up for this group was 69 months (range 14 to 200 months). There have been no recurrences of tumor in these recipients and the 1-, 3-, and 5-year patient and graft survivals are 100%, 100%, and 93%. Conclusions These data represent the only data available (to our knowledge) on this issue. This experience indicates that donor kidneys with small, incidental RCC and low histological grade (Furhman grade I and II/IV) can be managed with excision and transplantation, with a low risk of tumor recurrence in the recipient.

P olyomavirus nephropathy occurs in 5% of kidney transplant recipients. However, the role of individual immunosuppression agents in the pathogenesis of polyomavirus nephropathy is not known. The purpose of this study was to determine whether immunosuppression regimens with early steroid cessation–steroid avoidance influence the incidence of polyomavirus nephropathy. Retrospective, single-center analysis of kidney transplant recipients and kidney-pancreas transplant recipients performed from May 2000, when early steroid cessation–steroid avoidance immunosuppression regimens were instituted in our center (early steroid cessation, 7 days or less of steroids; steroid avoidance, no preoperative or postoperative steroids) (Table 1). Chi-square statistical analysis was performed, and a P value of .05 was considered to be statistically significant. As a result, 228 kidney transplants and 15 kidneypancreas transplants were performed between May 1, 2000, and Dec 31, 2002. Polyomavirus nephropathy occurred in 4 of 105 (4%) patients on a regimen of steroid-based immunosuppression. Polyomavirus nephropathy developed in 3 patients with kidney transplants and 1 with a kidney-pancreas transplant at a median of 13 (range, 8-16) months after transplantation. In contrast, of 138 patients receiving early steroid cessation–steroid avoidance immunosuppression, none (0%) had development of polyomavirus nephropathy (P .02). A similar trend was observed when early steroid cessation–steroid avoidance patients were compared with kidney transplant patients on a steroid-based immunosuppression regimen (3% v 0%, P .03). These results support those reported by Hirsch et al,1 who found antirejection treatment with steroids to be associated with polyomavirus nephropathy (P .02) in a multivariate analysis. Thymoglobulin induction versus none, cyclosporine versus tacrolimus, mycophenolate mofetil versus azathioprine, and sirolimus versus none were From the Division of Transplantation, University of Cincinnati, Cincinnati, OH; and Center for Neurovirology and Cancer Biology, Temple University, Philadelphia, PA. © 2003 Elsevier Inc. All rights reserved. 0955-470X/03/1704-0000$30.00/0 doi:10.1016/j.trre.2003.10.020 Table 1. Overall Immunosuppressive Regimens for All Transplant Recipients Analyzed

OKT3 is an IgG2a murine monoclonal antibody directed against the CD3 antigen receptor of human T lymphocytes. A major concern with OKT3 treatment in solid organ transplant recipients is the development of antimouse antibody, which may preclude retreatment with this agent. We have administered OKT3 on 215 occasions (150 renal, 34 hepatic, 26 cardiac, 5 pancreatic) in 179 patients between April 1982 and December 1988. The mean duration of treatment was 10.5 days (range, 2-22 days). Antimouse antibody data were analyzed on the most recent 133 treatment courses where the antibody status was available pretreatment. Determination of antimouse antibody production was elicited by ELISA technology at days 0, 7, 14, and 28 of OKT3 treatment. Patients were categorized according to the antibody response as follows: (a) absence of antibody; (b) low titer (1:100); or (c) high titer (greater than or equal to 1:1000). Our earlier experience has demonstrated that retreatment with OKT3 is successful in groups a and b. The development of antimurine antibodies was analyzed with regard to the following parameters: (1) The duration of OKT3 treatment; (2) treatment type (prophylactic, primary, or secondary); (3) primary treatment or retreatment; (4) concomitant immunosuppressive regimen (double or triple therapy); (5) dosage of concomitant immunosuppressive drugs; and (6) transplant organ type. The following results were obtained. (1) Duration of treatment had no effect on antibody production (11.0 days in antibody negative and 10.0 days in antibody positive). (2) There was no difference in antibody formation rates for the first treatment of OKT3 when it was used as prophylaxis (26%), primary (19%), or secondary (27%) therapy. (3) Antibody formation rate with first treatment was 29%; with retreatment, patients who were antibody negative following first treatment became positive in 28% of cases, and retreated patients who were low titer positive following first treatment converted to high titer in 57% of cases. (4) Antibody formation was higher in patients receiving double immunosuppressive therapy (36%) than in those receiving triple immunosuppressive therapy (21%) during OKT3 treatment. (5) Concomitant immunosuppression was lower in the antibody-positive group during OKT3 therapy: steroids, 61 mg/day vs. 52 mg/day; azathioprine, 89 mg/day vs. 66 mg/day; CsA, 317 mg/day vs. 186 mg/day. (6) Antibody formation rates were lower in non-renal transplants following first treatment with OKT3 (liver 17%, heart 17%, kidney 28%); this reflects the higher doses of concomitant immunosuppressive therapy used in nonrenal transplants.(ABSTRACT TRUNCATED AT 400 WORDS)

Orthoclone OKT3 is a murine monoclonal antibody that blocks the generation and function of T lymphocytes. It has been shown to be effective in reversing acute cellular rejection in solid organ transplants. However, potential development of antimurine antibodies restricts the duration that the drug can be used and the ability to reuse the drug. The case reported in this article illustrates the failure of retreatment with OKT3 when high titer (1:3200) antimurine antibodies are present. Lack of efficacy of the drug was documented by virtually undetectable circulating OKT3 levels in plasma, no decrease in T3 lymphocytes, and organ rejection. OKT3 should only be reused when immune monitoring (antimurine antibody status, lymphocyte subsets, and OKT3 plasma levels) is performed before, during, and after its use. Patients with high-titer anti-OKT3 antibody should not be retreated with OKT3.

Alternative techniques for handling multiple renal vessels in living related kidney transplants by use of the hypogastric artery are presented. This vessel can be used either as a tubular vascular graft or as a Carrel patch graft. Details of these techniques are discussed.

8 cases of Pneumocystis carinii pneumonia occurred in a population of 331 kidney transplant recipients receiving 393 transplants at the University of Cincinnati Medical Center betwe

The management of 23 patients with traumatic pseudoaneurysms is presented. A pulsatile mass associated with pain was the usual presentation. Hypertension and hypovolemic shock from rupture are uncommon presentations but potential hazards of this lesion. Twenty-one pseudoaaeurysms were treated surgically. Resection with end-to-end anastomosis (eight patients), with graft replacement (one patient), with lateral repair (seven patients) was done. Hypothermia with circulatory arrest and external Dacron shunt were used to prevent visceral ischemia during high aortic occlusion. There were no mortalities or significant postoperative complications.

During 1968-1973, 122 patients with 126 arterial injuries were treated. In 94 instances (90 patients), these injuries involved extremities. Systolic blood pressure was below 90 mm Hg upon admission in 55.6% of all patients and 37.7% of those with injuries to arteries of the extremities. The decision for operative exploration and repair of arteries of extremities was based largely on clinical grounds (shock, loss of pulse). Preoperative arteriography was needed infrequently, while operative angiography was nearly routine. Although several cases of late revascularization or traumatic thrombosis of renal artery have been reported, hypertension complicates the postoperative period, and early, aggressive approach is essential. Mortality was 10.6%, from aortic injuries. There were no deaths among patients with arterial injuries distal to inguinal ligament or thoracic outlet. The amputation rate from reconstruction failure was 1.1%, none occurring in the last 3 years of the series. The high patency rate and lack of evidence of pulmonary embolization suggest that associated venous injuries be repaired routinely. Arterial injuries represent ideal lesions (normal arterial wall with excellent run-in and run-off). Prompt treatment of shock and early, proper management of patients' mechanical disruptions will salvage many lives and most limbs.

Older patients (>50 years old) are generally considered to be at high risk in renal transplantation, particularly those receiving cadaveric kidneys. The outcome in 53 older patients (mean age, 54 years; range, 50 to 64 years) receiving transplants between January 1, 1980 and December 31, 1986 and followed through June 30, 1987 were analyzed. Before 1984, immunosuppression consisted of azathioprine and prednisone (AP); thereafter, triple therapy (TT)-low-dose cyclosporine, azathioprine, and prednisone-was used. The overall 1-, 3-, and 5-year actuarial patient survival was 87%, 84%, and 84%, respectively. Survival for living related donor (LRD) transplant recipients was 100%, 92%, and 92%; survival for cadaveric (CAD) transplant recipients was 81%, 81 %, and 81 %. The overall graft survival was 74%, 66%, and 66% at 1, 3, and 5 years, respectively; graft survival was 88%, 81%, and 81% for LRD transplant recipients and 68%, 58%, and 58%, for CAD recipients. The patient and graft survival rates were better in the TT group than in the AP group. Eight patients died after transplantation; six within the first year. The causes of patient death were infection (50%), cardiac (25%), and malignancy (25%). Rejection (56%) and patient death (38%) accounted for most of the grafts lost. Patient and graft survival rates in diabetic patients were not significantly different from survival rates in nondiabetic patients. Results in recipients of ten secondary and one tertiary transplant were poor, with only four of 11 grafts functioning at 1 year. Infectious complications were common, and steroid-induced diabetes occurred in 16% of patients whose grafts functioned > 1 month. It was concluded that results of primary renal transplantation in older patients have significantly improved in recent years. Transplantation should be the preferred modality of treatment for end-stage renal disease in patients aged 50 to 64 years in the absence of obvious contraindications.