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Transplantation | 1993

Risk factors for chronic rejection in renal allograft recipients.

P. S. Almond; Arthur J. Matas; K. J. Gillingham; David L. Dunn; William D. Payne; Paul F. Gores; Rainer W. G. Gruessner; Najarian Js

Chronic rejection is a major barrier to long-term renal allograft survival. Cyclosporine, though effective at reducing graft loss to acute rejection, has had little impact on the incidence of chronic rejection. Between June 2, 1986 and January 22, 1991, 587 kidney-alone transplants (566 patients) were performed, and had been entered into our renal transplant database and had at least 1 year of follow-up: 103 with biopsy-proven chronic rejection (37 living-related donor, 66 cadaver) and 484 without chronic rejection (236 LRD 248 CAD). The 5-year patient survival was 84% for recipients with biopsy-proven chronic rejection vs. 89% without (P = .08). The 5-year graft survival was 31% for recipients with biopsy-proven chronic rejection vs. 81% without (P < .0001). Using multivariate analysis, we determined the impact on the incidence of chronic rejection of these variables: transplant number, age at transplant (< 18 years, 18 to 50 years, > 50 years), gender, human leukocyte antigen matching, peak and transplant panel-reactive antibody, acute rejection episodes, infections (including cytomegalovirus, viral, and bacterial), donor age, and CsA dosage at 1 year (< 5 mg/kg vs. > or = 5 mg/kg). Logistic regression models were fit to the data using a forward stepwise selection procedure. In this analysis, risk factors included an acute rejection episode (P < .001), CsA dosage < 5 mg/kg/day at 1 year (P = .007), infection (P = .023), female gender (P = .042), and retransplant (P = .103). Individual analyses were done for CAD and LRD recipients. For both groups, important variables were acute rejection, infection, CsA dosage at 1 year, and age at transplant. In conclusion, acute rejection, CsA dosage < 5 mg/kg/day at 1 year, and infection are the major risk factors for the development of chronic rejection, suggesting that chronic rejection may be the result of inadequate immunosuppression (acute rejection episodes and low CsA dosage) or the production of inflammatory cytokines (infections).


Annals of Surgery | 2001

Lessons learned from more than 1,000 pancreas transplants at a single institution

David E. R. Sutherland; Rainer W. G. Gruessner; David L. Dunn; Arthur J. Matas; Abhinav Humar; Raja Kandaswamy; S. M. Mauer; William R. Kennedy; Frederick C. Goetz; R. P. Robertson; Angelika C. Gruessner; Najarian Js

ObjectiveTo determine outcome in diabetic pancreas transplant recipients according to risk factors and the surgical techniques and immunosuppressive protocols that evolved during a 33-year period at a single institution. Summary Background DataInsulin-dependent diabetes mellitus is associated with a high incidence of management problems and secondary complications. Clinical pancreas transplantation began at the University of Minnesota in 1966, initially with a high failure rate, but outcome improved in parallel with other organ transplants. The authors retrospectively analyzed the factors associated with the increased success rate of pancreas transplants. MethodsFrom December 16, 1966, to March 31, 2000, the authors performed 1,194 pancreas transplants (111 from living donors; 191 retransplants): 498 simultaneous pancreas–kidney (SPK) and 1 simultaneous pancreas–liver transplant; 404 pancreas after kidney (PAK) transplants; and 291 pancreas transplants alone (PTA). The analyses were divided into five eras: era 0, 1966 to 1973 (n = 14), historical; era 1, 1978 to 1986 (n = 148), transition to cyclosporine for immunosuppression, multiple duct management techniques, and only solitary (PAK and PTA) transplants; era 2, 1986 to 1994 (n = 461), all categories (SPK, PAK, and PTA), predominately bladder drainage for graft duct management, and primarily triple therapy (cyclosporine, azathioprine, and prednisone) for maintenance immunosuppression; era 3, 1994 to 1998 (n = 286), tacrolimus and mycophenolate mofetil used; and era 4, 1998 to 2000 (n = 275), use of daclizumab for induction immunosuppression, primarily enteric drainage for SPK transplants, pretransplant immunosuppression in candidates awaiting PTA. ResultsPatient and primary cadaver pancreas graft functional (insulin-independence) survival rates at 1 year by category and era were as follows: SPK, era 2 (n = 214) versus eras 3 and 4 combined (n = 212), 85% and 64% versus 92% and 79%, respectively; PAK, era 1 (n = 36) versus 2 (n = 61) versus 3 (n = 84) versus 4 (n = 92), 86% and 17%, 98% and 59%, 98% and 76%, and 98% and 81%, respectively; in PTA, era 1 (n = 36) versus 2 (n = 72) versus 3 (n = 30) versus 4 (n = 40), 77% and 31%, 99% and 50%, 90% and 67%, and 100% and 88%, respectively. In eras 3 and 4 combined for primary cadaver SPK transplants, pancreas graft survival rates were significantly higher with bladder drainage (n = 136) than enteric drainage (n = 70), 82% versus 74% at 1 year (P = .03). Increasing recipient age had an adverse effect on outcome only in SPK recipients. Vascular disease was common (in eras 3 and 4, 27% of SPK recipients had a pretransplant myocardial infarction and 40% had a coronary artery bypass); those with no vascular disease had significantly higher patient and graft survival rates in the SPK and PAK categories. Living donor segmental pancreas transplants were associated with higher technically successful graft survival rates in each era, predominately solitary (PAK and PTA) in eras 1 and 2 and SPK in eras 3 and 4. Diabetic secondary complications were ameliorated in some recipients, and quality of life studies showed significant gains after the transplant in all recipient categories. ConclusionsPatient and graft survival rates have significantly improved over time as surgical techniques and immunosuppressive protocols have evolved. Eventually, islet transplants will replace pancreas transplants for suitable candidates, but currently pancreas transplants can be applied and should be an option at all stages of diabetes. Early transplants are preferable for labile diabetes, but even patients with advanced complications can benefit.


American Journal of Transplantation | 2005

Immunosuppression: Evolution in practice and trends, 1993-2003

Herwig-Ulf Meier-Kriesche; S. Li; Rainer W. G. Gruessner; John J. Fung; R. T. Bustami; Mark L. Barr; Alan B. Leichtman

Over the last 10 years, there have been important changes in immunosuppression management and strategies for solid‐organ transplantation, characterized by the use of new immunosuppressive agents and regimens. An organ‐by‐organ review of OPTN/SRTR data showed several important trends in immunosuppression practice. There is an increasing trend toward the use of induction therapy with antibodies, which was used for most kidney, pancreas after kidney (PAK), simultaneous pancreas‐kidney (SPK) and pancreas transplant alone (PTA) recipients in 2004 (72–81%) and for approximately half of all intestine, heart and lung recipients. The highest usage of the tacrolimus/mycophenolate mofetil combination as discharge regimen was reported for SPK (72%) and PAK (64%) recipients. Maintenance of the original discharge regimen through the first 3 years following transplantation varied significantly by organ and drug. The usage of calcineurin inhibitors for maintenance therapy was characterized by a clear transition from cyclosporine to tacrolimus. Corticosteroids were administered to the majority of patients; however, steroid‐avoidance and steroid‐withdrawal protocols have become increasingly common. The percentage of patients treated for acute rejection during the first year following transplantation has continued to decline, reaching 13% for those who received a kidney in 2003, 48% of which cases were treated with antibodies.


Transplantation | 1995

Delayed Graft Function, Acute Rejection, And Outcome After Cadaver Renal Transplantation: A Multivariate Analysis

C. Troppmann; K. J. Gillingham; Enrico Benedetti; P. S. Almond; Rainer W. G. Gruessner; Najarian Js; Arthur J. Matas

The impact of delayed graft function on outcome after cadaver renal transplantation has been controversial, but most authors fail to control their analyses for the presence or absence of rejection. We studied 457 adult recipients of primary cadaver allografts at a single institution during the cyclosporine era. All patients received sequential immunosuppression. The incidence of delayed graft function (defined as dialysis being required during the first week after transplant) was 23%. There was a significant association between delayed graft function and cold ischemia time > 24 hr (P = 0.0001) and between delayed graft function and the occurrence of at least one biopsy-proven rejection episode (P = 0.004). Actuarial graft survival was not significantly different when comparing delayed graft function versus no delayed graft function for patients without rejection (P = 0.02). However, it was significantly worse for patients with both delayed graft function and rejection versus those with delayed graft function but no rejection (P = 0.005), as well as for grafts preserved > 24 hr versus < or = 24 hr (P = 0.007). By multivariate analysis, delayed graft function per se was not a significant risk factor for decreased graft survival for patients without rejection (P = 0.42). In contrast, rejection significantly decreased graft survival for grafts with immediate function (relative risk = 2.3, P = 0.0002), particularly in combination with delayed graft function (relative risk = 4.2, P < 0.0001). While cold ischemia time > 24 hr was also a significant risk factor (relative risk = 1.9, P = 0.02), other variables (preservation mode, 0 HLA Ag mismatch, age at transplantation, gender, diabetic status, and panel-reactive antibody at transplantation) had no impact on graft survival. Patient survival was significantly affected by the combination of delayed graft function and rejection (relative risk = 3.1, P < 0.0001), age at transplantation > 50 years (relative risk = 2.6, P < 0.0001), and diabetes (relative risk = 1.8, P = 0.006). Further studies are necessary to elucidate the mechanisms linking delayed graft function and rejection, which, in combination, lead to poor allograft outcome.


Transplantation | 2006

A Report of the Vancouver Forum on the Care of the Live Organ Donor: Lung, Liver, Pancreas, and Intestine Data and Medical Guidelines

Mark L. Barr; Jacques Belghiti; Federico G. Villamil; Elizabeth A. Pomfret; David S. Sutherland; Rainer W. G. Gruessner; Alan N. Langnas; Francis L. Delmonico

An international conference of transplant physicians, surgeons, and allied health professionals was held in Vancouver, Canada, on September 15 and 16, 2005 to address the care of the live lung, liver, pancreas, and intestine organ donor. The Vancouver Forum was convened under the auspices of the Ethics Committee of The Transplantation Society. Forum participants included over 100 leaders in organ transplantation, representing many countries from around the world, including participants from the following continents: Africa, Asia, Australia, Europe, North and South America. The objective of the Vancouver Forum was to develop an international standard of care for the live lung, liver, pancreas and intestinal organ donor. This Vancouver Forum followed a conference convened in Amsterdam on the care of the live kidney donor (1, 2). There were four organ specific work groups at the Vancouver Forum: lung, liver, pancreas and intestine. Each organ work group addressed the following topics in concert and reported their findings in a plenary presentation to all participants:


American Journal of Transplantation | 2004

Mortality Assessment for Pancreas Transplants

Rainer W. G. Gruessner; David E. R. Sutherland; Angelika C. Gruessner

We determined and compared the mortality of pancreas transplant recipients and of patients on the pancreas waiting lists by using United Network for Organ Sharing (UNOS) and International Pancreas Transplant Registry (IPTR) data. From January 1, 1995, through May 31, 2003, a total of 12 478 patients were listed for a simultaneous pancreas‐kidney (SPK) transplant; 2942 for a pancreas after (previous) kidney transplant (PAK); and 1207 for a pancreas transplant alone (PTA). In this retrospective observational cohort study, patients with multiple listings at different transplant centers and patients who changed transplant centers were counted only once. The Social Security Death Master File (SSDMF) and the UNOS kidney transplant database were used to update mortality information.


Annals of Surgery | 2000

Decreased surgical risks of pancreas transplantation in the modern era.

Abhinav Humar; Raja Kandaswamy; Darla K. Granger; Rainer W. G. Gruessner; Angelika C. Gruessner; David E. R. Sutherland

OBJECTIVE To document the decreased incidence of surgical complications after pancreas transplantation in recent times. SUMMARY BACKGROUND DATA Compared with other abdominal transplants, pancreas transplants have historically had the highest incidence of surgical complications. However, over the past few years, the authors have noted a significant decrease in the incidence of surgical complications. METHODS The authors studied the incidence of early (<3 months after transplant) surgical complications (e.g., relaparotomy, thrombosis, infections, leaks) after 580 pancreas transplants performed during a 12-year period. Patients were analyzed and compared in two time groups: era 1 (June 1, 1985, to April 30, 1994, n = 367) and era 2 (May 1, 1994, to June 30, 1997, n = 213). RESULTS Overall, surgical complications were significantly reduced in era 2 compared with era 1. The relaparotomy rate decreased from 32.4% in era 1 to 18.8% in era 2. Significant risk factors for early relaparotomy were donor age older than 40 years and recipient obesity. Recipients with relaparotomy had significantly lower graft survival rates than those without relaparotomy, but patient survival rates were not significantly different. A major factor contributing to the lower relaparotomy rate in era 2 was a significant decrease in the incidence of graft thrombosis; the authors believe this lower incidence is due to the routine use of postoperative low-dose intravenous heparin and acetylsalicylic acid. The incidence of bleeding requiring relaparotomy did not differ between the two eras. Older donor age was the most significant risk factor for graft thrombosis. The incidence of intraabdominal infections significantly decreased between the two eras; this decrease may be due to improved prophylaxis regimens in the first postoperative week. CONCLUSIONS Although a retrospective study has its limits, the results of this study, the largest single-center experience to date, show a significant decrease in the surgical risk associated with pancreas transplants. Reasons for this decrease are identification of donor and recipient risk factors, better prophylaxis regimens, refinements in surgical technique, and improved immunosuppressive regimens. These improved results suggest that more widespread application of pancreas transplantation is warranted.


Transplantation | 2004

Technical failures after pancreas transplants: Why grafts fail and the risk factors: A multivariate analysis

Abhinav Humar; Thigarajan Ramcharan; Raja Kandaswamy; Rainer W. G. Gruessner; Angelika C. Gruessner; David E. R. Sutherland

Background. Technical failure (TF) rates remain high after pancreas transplants; while rates have decreased over the last decade, more than 10% of all pancreas grafts continue to be lost due to technical reasons. We performed a multivariate analysis to determine causes and risk factors for TF of pancreas grafts. Results. Between 1994 and 2003, 937 pancreas transplants were performed at our center in the following transplant categories: simultaneous pancreas-kidney (SPK) (n=327), pancreas after kidney (PAK) (n=399), and pancreas transplant alone (PTA) (n=211). Of these, 123 (13.1%) grafts were lost due to technical reasons (thrombosis, leaks, infections). TF rates were higher for SPK (15.3%) versus PAK (12.2%) or PTA (11.4%), though this was not statistically significant. Thrombosis accounted for 52.0% of all TFs. Other causes were infections (18.7%), pancreatitis (20.3%), leaks (6.5%), and bleeding (2.4%). Thrombosis was the most common cause for TF in all three transplant categories. By multivariate analysis, the following were significant risk factors for TF of the graft: recipient body mass index (BMI) >30 kg/m2 (relative risk [RR]=2.42, P=0.0003), preservation time >24 hr (1.87, P=0.04), cause of donor death other than trauma (RR=1.58, P=0.04), enteric versus bladder drainage (1.68, P=0.06), and donor BMI >30 kg/m2 (1.66, P=0.06). Not significant were donor or recipient age, a retransplant, and the category of transplant. Conclusions. TFs remain significant after pancreas transplants. In SPK recipients, TF represents the most common cause of pancreas graft loss. For isolated pancreas transplants, TF is second only to rejection as a cause of graft loss. Increased preservation times and donor or recipient obesity seem to be risk factors. Minimizing these risks factors would be important to try to decrease TF.


Annals of Surgery | 2001

2,500 living donor kidney transplants: A single-center experience

Arthur J. Matas; William D. Payne; David E. R. Sutherland; Abhi Humar; Rainer W. G. Gruessner; Raja Kandaswamy; David L. Dunn; Kristen J. Gillingham; John S. Najarian

ObjectiveTo review a single center’s experience and outcome with living donor transplants. Summary Background DataOutcome after living donor transplants is better than after cadaver donor transplants. Since the inception of the authors’ program, they have performed 2,540 living donor transplants. For the most recent cohort of recipients, improvements in patient care and immunosuppressive protocols have improved outcome. In this review, the authors analyzed outcome in relation to protocol. MethodsThe authors studied patient and graft survival by decade. For those transplanted in the 1990s, the impact of immunosuppressive protocol, donor source, diabetes, and preemptive transplantation was analyzed. The incidence of rejection, posttransplant steroid-related complications, and return to work was determined. Finally, multivariate analysis was used to study risk factors for worse 1-year graft survival and, for those with graft function at 1 year, to study risk factors for worse long-term survival. ResultsFor each decade since 1960, outcome has improved after living donor transplants. Compared with patients transplanted in the 1960s, those transplanted in the 1990s have better 8-year actuarial patient and graft survival rates. Death with function and chronic rejection have continued to be a major cause of graft loss, whereas acute rejection has become a rare cause of graft loss. Cardiovascular deaths have become a more predominant cause of patient death; infection has decreased. Donor source (e.g., ideally HLA-identical sibling) continues to be important. For living donor transplants, rejection and graft survival rates are related to donor source. The authors show that patients who had preemptive transplants or less than 1 year of dialysis have better 5-year graft survival and more frequently return to full-time employment. Readmission and complications remain problems; of patients transplanted in the 1990s, only 36% never required readmission. Similarly, steroid-related complications remain common. The authors’ multivariate analysis shows that the major risk factor for worse 1-year graft survival was delayed graft function. For recipients with 1-year graft survival, risk factors for worse long-term outcome were pretransplant smoking, pretransplant peripheral vascular disease, pretransplant dialysis for more than 1 year, one or more acute rejection episodes, and donor age older than 55. ConclusionsThese data show that the outcome of living donor transplants has continued to improve. However, for living donors, donor source affects outcome. The authors also identify other major risk factors affecting both short- and long-term outcome.


Annals of Surgery | 1998

Surgical complications requiring early relaparotomy after pancreas transplantation: a multivariate risk factor and economic impact analysis of the cyclosporine era.

C. Troppmann; Angelika C. Gruessner; David L. Dunn; D. E. R. Sutherland; Rainer W. G. Gruessner

OBJECTIVES To study significant surgical complications requiring early (< or = 3 months posttransplant) relaparotomy (relap) after pancreas transplants, and to develop clinically relevant surgical and peritransplant decision-making guidelines for preventing and managing such complications. SUMMARY BACKGROUND DATA Pancreas grafts are still associated with the highest surgical complication rate of all routinely transplanted solid organs. However, the impact of surgical complications on morbidity, hospital costs, and graft and patient survival rates has not been analyzed in detail to date. METHODS We retrospectively studied surgical complications requiring relap in 441 consecutive cadaver, bladder-drained pancreas transplants (54% simultaneous pancreas and kidney [SPK]; 22% pancreas after kidney [PAK]; 24% pancreas transplant alone [PTA]; 37% retransplant). Outcome and hospital charges were analyzed separately for recipients with versus without reoperation. RESULTS The overall relap rate was 32% (SPK, 36%; PAK, 25%; PTA, 16%; p = 0.04). The most common causes were intraabdominal infection and graft pancreatitis (38%), pancreas graft thrombosis (27%), and anastomotic leak (15%). Perioperative relap mortality was 9%; transplant pancreatectomy was necessary in 57% of all recipients with one or more relaps. The pancreas graft was lost in 80% of recipients with versus 41% without relap (p < 0.0001). Patient survival rates were significantly lower (p < 0.05) for recipients with versus without relap. By multivariate analysis, significant risk factors for graft loss included older donor age (SPK, PAK), retransplant (PAK), relap for infection (SPK, PAK), and relap for leak or bleeding (PAK). For death, risk factors included older recipient age (SPK, PAK),retransplant (SPK, PAK), relap for thrombosis (PAK), relap for infection or leak (SPK), and relap for bleeding (PTA). CONCLUSIONS Posttransplant surgical complications requiring relap were frequent, resulted in a high rate of pancreas (SPK, PAK, PTA) and kidney (SPK, PAK) graft loss, and had a major economic impact (p = 0.0001). Complications were associated with substantial perioperative mortality and decreased patient survival rates. The focus must therefore shift from graft salvage to preservation of the recipients life once a pancreas graft-related complication requiring relap occurs. Thus, the threshold for pancreatectomy should be low. In this context, acceptance of older donors and recipients must be reconsidered.

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Abhinav Humar

University of Pittsburgh

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C. Troppmann

University of Minnesota

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