Kristen J. Gillingham

The impact of an acute rejection episode on long-term renal allograft survival (t1/2)

An acute renal transplant rejection episode has been shown to be associated with decreased 1-year graft survival. The impact on long-term outcome is undefined. We studied the impact of an acute rejection episode on t1/2, the time it takes for 1/2 of the grafts functioning at 1 year to fail. Use of t1/2 avoids inclusion of early graft loss to acute rejection or complications of treatment. Since 1/1/86, a total of 653 patients have received a primary kidney transplant and had at least 1 year of function. Recipients were divided by the incidence and timing of rejection: no rejection; 1 rejection within the first year; >1 rejection, the first episode in the first year; and ≥ rejection, the first episode after the first year. A single rejection episode in the first year reduced t1/2 (45±11 years in those with no rejection vs. 25±8 years in those with 1 in the first year). Multiple rejections (t1/2=5±11 years) and a first rejection after the first year (t1/2=3±1 years) have a significant effect (P<.05). Both living and cadaver donor recipients with rejection had shortened t1/2. For those with >1 rejection, the first episode in the first year, and those with ≥1 rejection, the first episode after the first year, chronic rejection was the predominant cause of graft loss; noncompliance also played a role. We conclude that a single rejection episode shortens t1/2. Those with >1 rejection, the first episode within the first year, and those with ≥1 rejection, the first episode after the first year, are at high risk for late graft loss.

Complications and risks of living donor nephrectomy

BACKGROUND Short- and long-term patient and graft survival rates are better for living donor (vs. cadaver) kidney transplant recipients. However, donor nephrectomy is associated with at least some morbidity and mortality. We have previously estimated the mortality of living donor nephrectomy to be 0.03%. In our present study, to determine associated perioperative morbidity, we reviewed donor nephrectomies performed at our institution from January 1, 1985, to December 31, 1995. METHODS The records of 871 donors were complete and available for review. Of these donors, 380 (44%) were male and 491 (56%) were female. The mean age at the time of donation was 38 years (range: 17-74 years), and mean postoperative stay was 4.9 days (range: 2-14 days). RESULTS We noted two (0.2%) major complications: femoral nerve compression with resulting weakness, and a retained sponge that required reexploration. We noted 86 minor complications in 69 (8%) donors: 22 (2.4%) suspected wound infections (only 1 wound was opened), 13 (1.5%) pneumothoraces (6 required intervention, 7 resolved spontaneously), 11 (1.3%) unexplained fevers, 8 (0.9%) instances of operative blood loss > or = 750 ml (not associated with other complications), 8 (0.9%) pneumonias (all of which resolved quickly with antibiotics alone), 5 (0.6%) wound hematomas or seromas (none were opened), 4 (0.5%) phlebitic intravenous sites, 3 (0.3%) urinary tract infections, 3 (0.3%) readmissions (2 for pain control and 1 for mild confusion that resolved with discontinuation of narcotics), 3 (0.3%) cases of atelectasis, 2 (0.2%) corneal abrasions, 1 (0.1%) subacute epididymitis, 1 (0.1%) Clostridium difficile colitis, 1 (0.1%) urethral trauma from catheter placement, and 1 (0.1%) enterotomy. At our institution, no donor died or required ventilation or intensive care. We noted no myocardial infarctions, deep wound infections, or reexplorations for bleeding. Analysis, by logistic regression, identified these significant risk factors for perioperative complications: male gender (vs. female, P<0.001), pleural entry (vs. no pleural entry, P<0.004), and weight > or = 100 kg (vs. < 100 kg, P<0.02). Similar analysis identified these significant risk factors for postoperative stay > 5 days: operative duration > or = 4 hr (vs. < 4 hr, P<0.001) and age > or = 50 years (vs. < 50 years, P<0.001). CONCLUSIONS Living donor nephrectomy can be done with little major morbidity. The risks of nephrectomy must be balanced against the better outcome for recipients of living donor transplants.

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

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.

Are wound complications after a kidney transplant more common with modern immunosuppression

Background. The most common surgical complication after a kidney transplant is likely related to the wound. The purpose of this analysis was to determine the incidence of, and risk factors for, wound complications (e.g., infections, hernias) in kidney recipients and to assess whether newer immunosuppressive drugs increase the risk for such complications. Methods. Between January 1, 1984 and September 30, 1998, we performed 2013 adult kidney transplants. Of these 2013 recipients, 97 (4.8%) developed either a superficial or a deep wound infection. Additionally, 73 (3.6%) recipients developed either a fascial dehiscence or a hernia of the wound. We used univariate and multivariate techniques to determine significant risk factors and outcomes. Results. Mean time to development of a superficial infection (defined as located above the fascia) was 11.9 days posttransplant; to development of a deep infection (defined as located below the fascia), 39.2 days; and to development of a hernia or fascial dehiscence, 12.8 months. By multivariate analysis, the most significant risk factor for a superficial or deep wound infection was obesity (defined as body mass index>30 kg/m2) (RR=4.4, P =0.0001). Other significant risk factors were a urine leak posttransplant, any reoperation through the transplant incision, diabetes, and the use of mycophenolate mofetil (MMF) (vs. azathioprine) for maintenance immunosuppression (RR=2.43, P =0.0001). Significant risk factors for a hernia or fascial dehiscence were any reoperation through the transplant incision, increased recipient age, obesity, and the use of MMF (vs. azathioprine) for maintenance immunosuppression (RR=3.54, P =0.0004). Use of antibody induction and treatment for acute rejection were not significant risk factors for either infections or hernias. Death-censored graft survival was lower in recipients who developed a wound infection (vs. those who did not); it was not lower in recipients who developed an incisional hernia or facial dehiscence (vs. those who did not). Conclusions. Despite immunosuppression including chronic steroids, the incidence of wound infections, incisional hernias, and fascial dehiscence is low in kidney recipients. As with other types of surgery, the main risk factors for postoperative complications are obesity, reoperation, and increased age. However, in kidney recipients, use of MMF (vs. azathioprine) is an additional risk factor –one that potentially could be altered, especially in high-risk recipients.

Causes of renal allograft loss. Progress in the 1980s, challenges for the 1990s.

A variety of refinements in the care of kidney transplant recipients have been instituted over the past decade. The authors studied the overall impact of these refinements on kidney allograft losses at a single institution. To do this they compared the causes and rates of graft loss for primary kidney transplants in the 1970s (January 1,1970 to December 31,1979; n = 1012; 657 nondi-abetics, 355 diabetics; 617 living donors, 395 cadaver donors) versus the 1980s (January 1, 1980 to December 31, 1989; n = 1,384; 756 nondiabetics, 628 diabetics; 740 living donors, 644 cadaver donors). Overall patient survival improved significantly, with rates at 1, 5, and 10 years of 94%, 84%, and 68% for the 1980s, compared with 86%, 69%, and 57% for the 1970s (p < 0.001). Actuarial graft survival also improved significantly, with rates at 1, 5, and 10 years of 86%, 71%, and 52% for the 1980s, compared with 73%, 58%, and 43% for the 1970s (p < 0.001). This improvement occurred even though there were proportionately more cadaver donors and diabetic recipients in the 1980s. For both decades combined, 24% of the lost grafts were due to chronic rejection, 18% to cardiovascular causes of death with function, 13% to infectious causes of death with function, and 11% to acute rejection. The overall gain in graft survival rates in the 1980s was principally due to fewer cases of acute rejection and fewer infectious deaths. Improvement in graft survival due to the two leading causes–chronic rejection and cardiovascular causes of death–was relatively small, if any. These data indicate that future kidney transplantation research should emphasize prevention of chronic rejection and cardiovascular death.

Delayed graft function in the absence of rejection has no long-term impact. A study of cadaver kidney recipients with good function at 1 year after transplantation

We previously reported that delayed graft function (DGF) in the absence of biopsy-proven acute rejection (Rej) had no effect on outcome of primary cadaver kidney transplantation (TX). By contrast, DGF in combination with Rej strongly predicted poor long-term graft survival. We asked whether this poor long-term outcome was due to early graft loss associated with DGF, or to an ongoing process leading to late graft loss. To answer this question, we studied a subset of 298 cadaver kidney transplant recipients who had not suffered early graft loss and had a serum creatinine level < or = 2.0 mg/dl at 1 year after TX. The incidence of DGF (defined by dialysis during the first week after TX) in this subset was 19%. DGF was associated with cold ischemia time >24 hr (P = 0.0003) and Rej (P = 0.06). For grafts with versus without DGF, the incidence of late acute Rej (>1 year after TX) was similar. Actuarial graft survival was similar for Rej-free recipients with versus without DGF (P = 0.9) and was worse for those with Rej and no DGF (P < 0.02). Importantly, however, in our recipients who all had a serum creatinine level < or = 2.0 mg/dl at 1 year after TX, the worst long-term outcome was noted in the subgroup with both DGF and Rej (P < 0.0001). By multivariate analysis, DGF was also only a risk factor in combination with Rej (P = 0.002, relative risk = 3.7), while a 0-antigen HLA mismatch had no impact. Patient survival decreased for recipients with both DGF and Rej by univariate (P = 0.009) and multivariate (P = 0.02, relative risk = 2.9) analyses. We conclude that DGF without Rej has no impact on long-term survival. However, our data for recipients with both DGF and Rej suggest that a chronic ongoing process leads to late graft failure. Further research is necessary to identify the exact pathophysiology of this process, which appears to be, at least in part, HLA antigen independent.

Prednisone-Free Maintenance Immunosuppression—A 5-Year Experience

Concern persists that prednisone‐free maintenance immunosuppression in kidney transplant recipients will be associated with an increase in late allograft dysfunction and graft loss. We herein report 5‐year follow‐up of a trial of prednisone‐free maintenance immunosuppression. From October 1, 1999, through January 31, 2005, at our center, 589 kidney transplant recipients were treated with a protocol incorporating discontinuation of their prednisone on postoperative day 6. At 5 years, actuarial patient survival was 91%; graft survival, 84%; death‐censored graft survival, 92%; acute rejection‐free graft survival, 84% and chronic rejection‐free graft survival, 87%. The mean serum creatinine level (±SD) at 1 year was 1.6 ± 0.6; at 5 years, 1.7 ± 0.8. In all, 86% of kidney recipients with functioning grafts remain prednisone‐free as of April 30, 2005.

Association between cytomegalovirus disease and chronic rejection in kidney transplant recipients.

BACKGROUND It has long been suggested that cytomegalovirus (CMV) disease plays a role in the pathogenesis of chronic rejection (CR). However, its role has been difficult to prove, given the strong association between acute rejection and CMV, and the even stronger association between acute rejection and CR. To try to isolate the relative contribution of CMV infection in the pathogenesis of CR, we used multivariate techniques to examine risk factors for CR, including CMV disease. METHODS Our study population consisted of adult recipients of a first kidney graft who underwent transplantation at a single center between 1/1/85 and 6/30/97 (n = 1339). RESULTS Multivariate analysis using time to CR as the dependent variable demonstrated acute rejection to be the strongest risk factor (relative risk [RR] = 17.8, P = 0.0001), followed by older donor age (RR = 1.46, P = 0.01). The presence of CMV disease showed a trend toward increased risk for CR (RR = 1.30, P = 0.10), although the association was not as strong as with the other two variables. Comparing only those recipients with acute rejection and CMV disease versus those with acute rejection but no CMV disease, the relative risk of developing CR was 1.37 times higher in the former group. Recipients with acute rejection and CMV developed CR sooner and with a higher incidence versus those with acute rejection but no CMV (P = 0.002). It is interesting, however, that CMV disease was only a risk factor for CR in the presence of acute rejection. Recipients with no acute rejection and CMV disease did not have a higher incidence of CR versus those with no acute rejection and no CMV (P = NS). CONCLUSION CMV disease seems to play some role in the pathogenesis of CR but only in the presence of acute rejection. Reasons may include (i) the inability to adequately treat acute rejection due to the presence of CMV disease or (ii) the increased virulence of latent CMV virus in recipients being treated for acute rejection. Our data may suggest a role for more aggressive prophylaxis against CMV disease, especially at the time of treatment for acute rejection.

The impact of the quality of initial graft function on cadaver kidney transplants

Living unrelated donor (LURD) transplants have immunologic barriers similar to cadaver transplants, yet the outcome is better (1-year graft survival = 96%). One advantage of LURD transplants is that, with the extremely short preservation time, the kidney functions immediately. We studied whether the quality of initial renal function affects the outcome of primary cadaver transplants. We divided 301 non-6-antigen-matched recipients transplanted between 1/1/86 and 8/1/92—who had no graft loss due to hyperacute rejection, primary non-function, or technical reasons—into 5 groups based on the quality of initial renal function (serum creatinine level in the first week). We determined patient and graft survival rates for each group. We found that the quality of initial function had a significant effect on patient and graft survival rates. Recipients whose serum creatinine level was <3 mg/dl on posttransplant day 5 (groups 1 and 2) had better patient and graft survival than either those whose serum creatinine level was >3 mg/dl on day 7 (group 4) or those who required dialysis (group 5). Because some early dysfunction may be immunologic, we reanalyzed the data excluding patients with percent reactive antibody ≥ 15; the quality of initial function in this group had a significant impact on outcome. Similarly, when patients with graft loss due to “death with function” ‘were excluded, the quality of initial function had a significant impact on survival rates. We conclude that the quality of early posttransplant function is an important predictor of long-term outcome. Cadaver recipients with immediate good function have outcomes similar to living donor recipients. Our data suggest that increased effort should be made to improve immediate posttransplant function.

Immunologic And Nonimmunologic Factors: Different Risks for Cadaver and Living Donor Transplantation 1

BACKGROUND There is a debate about the relative contribution of immunologic (rejection) and nonimmunologic (limited nephron mass) factors in long-term graft survival. METHODS Using multivariate analysis, we studied the association of the following variables with outcome: delayed graft function (DGF), acute rejection, recipient race (black vs. nonblack), donor age (<50 vs. > or =50), donor race, and donor and recipient gender. Because of the association between DGF and rejection, recipients were grouped as follows: DGF, rejection; DGF, no rejection; no DGF, rejection; no DGF, no rejection. Data were analyzed on 1199 first kidney transplants in adults (752 living donor, 447 cadaver donor) done between January 1, 1985 and December 31, 1996. Two analyses were done: first, all transplants; second, only those with > or =1 year survival. For both, there was no difference in risk factors if death with function was or was not censored. RESULTS For all cadaver transplant recipients, risk factors were acute rejection, DGF plus rejection, black recipient race, and donor age > or =50. For living donor recipients, only acute rejection was a risk factor. When only 1-year graft survivors were considered, risk factors were the same: for cadaver recipients, risk factors were acute rejection, DGF plus rejection, black recipient race, and donor age > or =50; for living donor recipients the risk factor was rejection. CONCLUSION We found immunologic factors (rejection with or without DGF) to be significant in both living donor and cadaver donor transplants. Nonim. munologic factors (donor age, recipient race) were significant only in cadaver donor transplants.