Living donors >55 years: to use or not to use?

BACKGROUND

Kidney transplants using older donors are becoming increasingly accepted as a strategy for alleviating the growing donor organ shortage. Most studies to date have shown decreased graft survival associated with the use of older cadaver donors; however, studies on the effect of living donor age on graft survival are less clear-cut.

METHODS

We studied the effect of donor age on patient and graft survival after 1126 consecutive cyclosporine-treated primary kidney transplants performed between January 1, 1985 and December 31, 1995. Of these grafts, 598 were from living donors (74 from donors >55 years old) and 528 from cadaver donors (54 from donors >55 years). We calculated actuarial patient survival, graft survival, and death-censored graft survival for recipients of both living donor and cadaver kidneys. Living donors were then further divided by HLA mismatch (0 vs. 1 - 6) and the presence or absence of an acute rejection episode. Multivariate analysis of factors associated with decreased graft survival was performed for recipients of both living and cadaver donor kidneys. Factors included for analysis were donor age >55 years, recipient age >50 years, the presence of diabetes mellitus, HLA mismatch (0 vs. 1 - 6), and the presence of an acute rejection episode.

RESULTS

For cadaver kidneys, univariate analysis indicates that both overall (P=0.004) and death-censored (P=0.001) graft survival was significantly better with younger cadaver kidneys. This is supported by our multivariate analysis, which shows that cadaver donor age >55 years is an independent predictor of poor actuarial graft survival (P=0.0003). For living donor kidneys, univariate analysis also indicates that both overall (P=0.045) and death-censored (P=0.005) graft survival was significantly better with younger living donor kidneys. However, in the absence of acute rejection, 10-year death-censored graft survival for patients with older vs. younger living donor kidneys was 93% vs. 94%, whereas in the presence of one or more acute rejection episodes, 10-year death-censored graft survival dropped markedly to 39% with older and 54% with younger living donors. Kidneys from living donors >55 years had significantly better long-term graft survival than cadaver donors >55 years (P=0.012) and had comparable graft survival to younger cadaver donors. In contrast to our univariate analysis, multivariate analysis of our living donor data shows that decreased actuarial living donor death-censored graft survival was significantly associated only with the presence of one or more acute rejection episodes (P<0.0001). Living donor age >55 years was not independently associated with decreased graft survival.

CONCLUSIONS

Ours is the largest single-center study of outcome for recipients of kidneys from living donors >55 years. Using univariate analysis, we have shown that graft survival of kidneys from older living donors is significantly better than that of kidneys from older cadaver donors and is comparable to that of kidneys from younger cadaver donors. Using multivariate analysis, we have shown that the presence of one or more acute rejection episodes significantly shortens both cadaver and living donor long-term graft survival. Most significantly, we have shown that, although the use of kidneys from cadaver donors >55 years is associated with significantly decreased long-term graft survival, no such association exists for recipients of kidneys from living donors >55 years. We feel that our data support the continued use of kidneys from older living donors.

Long-term follow-up of living kidney donors: quality of life after donation

The University of Minnesota has been a strong advocate of living donor kidney transplants. The benefits for living donor recipients have been well documented. The relative low risk of physical complications during donation has also been well documented. Less well understood is the psychosocial risk to donors. Most published reports have indicated an improved sense of well-being and a boost in self-esteem for living kidney donors. However, there have been some reports of depression and disrupted family relationships after donation, even suicide after a recipient's death. To determine the quality of life of our donors, we sent a questionnaire to 979 who had donated a kidney between August 1, 1984, and December 31, 1996. Of the 60% who responded, the vast majority had an excellent quality of life. As a group, they scored higher than the national norm on the SF-36, a standardized quality of life health questionnaire. However, 4% were dissatisfied and regretted the decision to donate. Further, 4% found the experience extremely stressful and 8% very stressful. We used multivariate analysis to identify risk factors for this poor psychosocial outcome and found that relatives other than first degree (odds ratio=3.5, P=0.06) and donors whose recipient died within 1 year of transplant (odds ratio=3.3, P=0.014) were more likely to say they would not donate again if it were possible. Further, donors who had perioperative complications (odds ratio=3.5, P=0.007) and female donors (odds ratio=1.8, P=0.1) were more likely to find the overall experience more stressful. Overall, the results of this study are overwhelmingly positive and have encouraged us to continue living donor kidney transplants.

Impact of transfusions and acute rejection on posttransplantation donor antigen-specific responses in two study populations. Cooperative Clinical Trial in Transplantation Research Group

BACKGROUND

We participated in a protocol supported by the National Institutes of Allergy and Infectious Disease, Cooperative Clinical Trial in Transplantation (CCTT), which was designed to investigate the effect of peritransplant donor-specific transfusion in non-HLA-identical living donor kidney recipients.

METHODS

We determined the donor antigen-specific responses at 1 year after transplantation for the 79 CCTT donor-recipient combinations in this study. A lower rate of donor antigen-specific hyporeactivity was seen in the CCTT recipients (6 of 79=8%) versus our recipients at the University of Minnesota who underwent transplantation in the same period (9 of 55=16%, P=0.16) and versus our combined historical data (33 of 131=25%, P=0.002). Therefore, we studied the differences in the two recipient populations to determine why hyporeactivity was lower in the CCTT group than at our center.

RESULTS

Significant differences were seen in the acute rejection rates and the frequency of pretransplantation random transfusion. Overall and early (<3 month) acute rejection rates were higher in CCTT versus Minnesota recipients (overall: 51% vs. 20%, P=0.001) (early: 43% vs. 16%, P=0.001). The frequency of pretransplantation random transfusion was 40% for CCTT recipients (34%) versus 80% for Minnesota recipients (75%) (P=0.0004).

CONCLUSIONS

These results provide provocative, although not conclusive, evidence for the importance of pretransplantation transfusion and acute rejection episodes in the development of donor antigen-specific hyporeactivity. Pre-, peri-, and posttransplantation clinical events undoubtedly have an impact on posttransplantation immune parameters.

Mouse-to-rabbit xenotransplantation: a new small animal model of hyperacute rejection mediated by the classical complement pathway

BACKGROUND

Hyperacute rejection of porcine organs transplanted into primate recipients is initiated by the binding of preformed xenoreactive natural antibodies to the vascular endothelium of the graft and activation of the classical complement pathway. Several small animal models are currently employed to study various aspects of xenograft rejection; however, none has been shown to manifest hyperacute rejection mediated by the classical pathway of complement activation.

METHODS

We performed heterotopic mouse heart transplants into weanling rabbits, adult rabbits, and C6-deficient rabbits. The recipients received no immunosuppression. Rejected grafts were subjected to histologic analysis and immunofluorescence staining for rabbit IgG, IgM, and C3. Levels of preexisting cytotoxic antibodies as well as classical and alternative complement pathway activities were determined in rabbit serum using mouse red cells as targets.

RESULTS

Mean graft survival was 37+/-9.6 min for mouse-to-weanling rabbit transplants (n=10), and 40+/-11.1 min for mouse-to-adult rabbit transplants (n=5). Rejected grafts showed diffuse interstitial hemorrhage, endothelial cell damage, myocyte necrosis, moderate diffuse deposition of rabbit IgG, and dense deposition of rabbit IgM and C3 on the vascular endothelium of the graft, consistent with hyperacute rejection. One mouse-to-C6-deficient rabbit transplant was rejected at 21 hr with severe interstitial hemorrhage, cellular necrosis and a moderate cellular infiltrate consisting primarily of neutrophils and some mononuclear cells. A second transplant in a C6-deficient rabbit was functioning when the recipient died at 6.5 hr as a result of complications of surgery; the graft had normal myocytes and vasculature with minimal spotty interstitial hemorrhage. Both weanling and adult rabbit serum were found to have high titers of cytotoxic IgM anti-mouse antibodies and strong classical complement pathway activity with minimal alternative pathway activity towards mouse red cells.

CONCLUSIONS

The mouse-to-rabbit species combination manifests hyperacute xenograft rejection. In vitro studies suggest that this process is mediated by IgM anti-mouse natural antibodies and activation of the classical pathway of complement.

Living kidney donation: donor risks and quality of life

This review describes the immediate and long-term risks to kidney donors. We reviewed their perioperative morbidity and mortality as well as their quality of life after donation. The overall mortality in our series was zero. Nationally, donor mortality has been estimated to be 0.03% (5). Our overall complication rate was 8.2% with only 2 (0.2%) complications considered to be major (16). Complications were associated with male sex, body weight > or = 100 kg, and inadvertent entry into the pleura during the donor operation. Most of our donors were discharged from the hospital in < 5 days. Risk factors for a longer hospital stay were age 50 or older and an operative time of 4 hours or more. The average donor quality of life after donation, as measured by the SF-36, was better than that of the general US population. This finding persisted for years after donation. The vast majority of our donors found the experience to be very rewarding and would readily donate again if it were possible. However, 4% were dissatisfied and regretted their decision to donate a kidney; these were most likely to be donors other than a first-degree relative and donors whose recipient died within the first posttransplant year. Living donation of kidneys appears to be relatively safe, with very few physical and psychologic complications. It may even improve the donor's quality of life. Living donors are an underutilized source of kidneys. We continue to advocate and encourage living kidney donation.

Current thinking on chronic renal allograft rejection: issues, concerns, and recommendations from a 1997 roundtable discussion

Chronic rejection accounts for most renal allograft losses after the first year posttransplantation. On March 24 and 25, 1997, a roundtable of five transplant surgeons, two nephrologists, and one pathologist assembled in Dallas, Texas, to review critical issues surrounding chronic renal allograft rejection. This article summarizes the presentations and relevant discussions of this meeting regarding the cause of chronic rejection, clinical diagnoses, risk factors, future prospects for intervention strategies, and general recommendations for the transplant community. Growing evidence indicates that chronic rejection is the aggregate sum of irreversible immunologic and nonimmunologic injuries to the renal graft over time. A history of acute rejection episodes and inadequate immunosuppression, likely attributable to inconsistent cyclosporine exposure or poor patient compliance, are among the most recognizable immunologic risk factors for chronic rejection. Donor organ quality, delayed graft function, and other donor and recipient variables leading to reduced nephron mass are nonimmunologic factors that contribute to the progressive deterioration of renal graft function. Clinical management of renal transplant recipients should incorporate both immunologic- and nonimmunologic-based intervention strategies aimed at minimizing risk factors to thwart the progression of chronic rejection and improve long-term allograft and patient survival.

Pre-emptive renal transplantation

We report our experience with pre-emptive renal transplantation and review the literature. While eliminating the cost, complications and inconvenience of dialysis, transplantation prior to dialysis therapy can be performed safely and effectively as it does not pose any additional immunological hazards to allograft outcome. It is safe regardless of the immunosuppressive agents employed and is successful without early rejection even in the nonuremic state.

Kidney transplantation in children younger than 1 year using cyclosporine immunosuppression

OBJECTIVE

The optimal age for transplantation in children with end-stage renal disease remains controversial. Supported by national data, many centers recommend dialysis until the child reaches a certain minimum age. The authors' policy, however, has been to encourage living donor (LD) transplants for young children, with no minimum age restriction.

METHODS

Between January 1, 1984, and December 31, 1996, the authors performed 248 kidney transplants in children younger than age 13 years, using cyclosporine as the primary immunosuppressive agent. Recipients were analyzed in three age groups: group 1, younger than age 1 year (n = 26); group 2, age 1 through 4 (n = 92); and group 3, age 5 through 13 (n = 130). Almost all recipients in group 1 underwent a primary LD transplant. Therefore, to compare results more meaningfully among the three age groups, only primary LD transplants were analyzed (group 1, n = 25; group 2, n = 59; group 3, n = 58).

RESULTS

In primary LD transplants, no significant difference was noted among the age groups in 1-and 5-year patient or graft survival rates. To date, all 25 recipients from group 1 are alive and well; 19 still have a functional original graft. Causes of graft loss in the remaining six recipients were chronic rejection (n = 3), vascular thrombosis (n = 2), and recurrent disease (n = 1). The incidence of acute rejection in group 1 recipients was lower than in the two older groups. However, the incidence of delayed graft function was slightly higher in the youngest group than in the two older groups. For recipients in group 1, growth (as measured by weight) improved significantly posttransplant: the mean standard deviation score rose from -2.8 pretransplant to -0.2 by age 5 and to +1.8 by age 10. The improvement in height was not as dramatic: the mean standard deviation score rose from -3.2 pretransplant to -1.6 by age 5 and to -1.4 by age 10.

CONCLUSIONS

Kidney transplantation in young children, including those younger than 1 year old, can achieve results comparable to those in older children. As long as an adult LD is available, the timing of the transplant should be based on renal function rather than age.

Long-term quality of life after kidney and simultaneous pancreas-kidney transplantation

We are using a validated questionnaire (SF-36) to annually assess health-related quality of life (QOL) in kidney and pancreas-kidney transplant recipients. The SF-36 consists of eight scales to assess physical functioning, general health, and mental functioning. Norms and 95% confidence intervals (C.I.) have been developed for the US population. At present, 1138 recipients with functioning grafts (520 Type I diabetic; 618 nondiabetic) 1-10 yr post-transplant have completed the questionnaire. Of the recipients, 446 completed the questionnaire once; 632 twice; and 53 three times (305 after 1 yr; 266 after 2 yr; 256 after 3 yr; 206 after 4 yr; 192 after 5 yr; 150 after 6 yr; 130 after 7 yr; 138 after 8 yr; 125 after 9 yr; 92 after 10 yr). For both diabetic and nondiabetic recipients, there was little change in average scores for each scale between years (p = NS). In relation to the US population, average scores for nondiabetics were below the 50th percentile on all 8 scales; for diabetics < 25th percentile on the physical functioning and vitality scales, < 50th percentile on all others. For both diabetic and nondiabetic recipients, average scores were higher than reported norms for patients with CHF, COPD, or depression but were similar to those with Htn or recent MI. Individual scores were then compared with age-matched means (+/- 2 SEMs) (95% C.I.) for the US population. At each year post-transplant, up to 40% of nondiabetic and up to 65% of diabetic recipients had scores below the 95% C.I. on individual scales (particularly the physical functioning and general health scales)--e.g. over 30% nondiabetic and up to 60% diabetic recipients had scores on the physical functioning scales below the 95% C.I. More diabetic recipients (vs. nondiabetics) reported poor QOL on the physical functioning, general health and social functioning scales. There was little difference in the mental health scales. For those with Type I diabetes, a similar percentage of kidney and K/P recipients reported QOL below the 95% C.I. for the age-matched population, except on the GH scale (better QOL for K/P recipients). We conclude that successful transplant recipients report health-related QOL below that of the age-matched general population but similar to those with other chronic diseases. Diabetic and nondiabetic recipients have similar scores on the mental health scales; nondiabetic recipients score better on the general health and physical functioning scales.

The acutely ischemic extremity after kidney transplant: an approach to management

BACKGROUND

The purpose of this study was to review arterial thromboembolic complications presenting with an acutely ischemic lower extremity after a kidney (KTx) or simultaneous kidney-pancreas transplantation (SPK) and to describe an approach to their management.

METHODS

We retrospectively reviewed all such transplantations (a total of 2109) performed between January 1985 and August 1995. We identified 16 recipients (incidence, 0.76%) in whom an acutely ischemic leg developed during the immediate postoperative period (within the first 48 hours).

RESULTS

Of the 16 recipients, eight underwent a KTx (incidence, 0.45%) and eight underwent an SPK transplantation (incidence, 2.90%). Median age was 38 years (range, 15 months to 61 years). Thirteen had insulin-dependent diabetes mellitus (IDDM), a significantly higher incidence than in the control group (i.e., transplant recipients without this complication) (p < 0.01). Peripheral vascular disease (PVD) was documented before operation in eight (50%) of the recipients (vs 8.9% in the control group) (p < 0.01). Ten were uremic (on chronic dialysis) before transplantation; six were nonuremic (not on dialysis). Intraoperatively, 14 had moderate to severe atherosclerotic disease affecting the iliac vessels, seven of whom required some manipulation of the artery (either endarterectomy or tacking of the intima) to make it suitable for anastomosis. Heparin was administered systemically during cross clamping to only four. Most of the 16 recipients showed symptoms or signs of arterial occlusion within the first few hours after operation. The most common symptom was pain; the most common physical finding was loss of femoral and distal pulses. Thirteen recipients had moderate to severe ischemia, as judged by physical examination; 15 returned to the operating room for surgical exploration. Eight underwent thrombectomy through an inguinal incision, with successful restoration of flow. Seven underwent exploration through the initial incision because of concern regarding the viability of the transplanted organ; five of them required transplant nephrectomy because of simultaneous thrombosis of the renal artery. No patient needed a bypass procedure to restore flow. Long-term morbidity as a result of the arterial occlusion was related to the severity and length of ischemia.

CONCLUSIONS

On the basis of these results, we suggest the following recommendations: (1) all patients should undergo a thorough peripheral vascular examination before and after transplantation; (2) patients at higher risk for arterial thromboembolic complications (e.g., those with significantly diseased vessel at intraoperative examination, nonuremic patients) should receive intraoperative systemic heparin before cross clamping of the artery; and (3) patients with signs or symptoms suggesting arterial occlusion after operation should undergo prompt surgical exploration.

Venous thromboembolic complications after kidney and kidney-pancreas transplantation: a multivariate analysis

BACKGROUND

We reviewed the incidence of and risk factors for venous thromboembolic complications in our population of kidney (KTx) and simultaneous kidney-pancreas transplant (SPK) recipients.

METHODS

Information was collected retrospectively from a database on 1833 KTx and 276 SPK recipients who underwent transplant surgery between January 1985 and August 1995.

RESULTS

The incidence of deep venous thrombosis (DVT) was 6.2% (n= 132), with significantly higher rates after SPK (18.1%) vs. KTx (4.5%) (P < 0.001). The number of DVT episodes was highest in the first month; 17.5% occurred during this time. For KTx recipients, early thrombotic events were more common on the side of the graft (P=0.03); however, after 1 month, no correlation existed between the side of the graft and the side of DVT. For SPK recipients, DVT tended to be more common on the side of the pancreas (57%) vs. the kidney (43%) (P=0.10). By multivariate analysis, risk factors for DVT were: age > 40 years (odds ratio [OR]=2.2, P < 0.001), diabetes mellitus (DM) (OR=2.0, P=0.002), previous DVT (OR=4.4, P=0.001), and SPK transplant (OR=2.8, P < 0.001). Pulmonary embolus (PE) was identified in 44 recipients (incidence, 2.1%) and was fatal in 13 (30%). The incidence was significantly higher in SPK (4.71%) vs. KTx recipients (1.69%) (P < 0.01). The risk of death from PE was 0.5% in KTx recipients and 1.37% in SPK recipients (P=0.08). Risk factors for PE included DM (OR=2.6, P=0.005) and recent DVT (OR=8.9, P=0.0001).

CONCLUSIONS

Based on risk and extrapolating from the general surgical literature, our recommendations for prophylaxis against DVT are use of graduated compression stockings for all recipients and, in addition, low-dose heparin for moderate and high-risk recipients (previous DVT, SPK, age > 40 years, DM).

Effect of early cyclosporine levels on kidney allograft rejection

Acute rejection is the greatest risk factor for development of biopsy-proven chronic rejection and late kidney allograft loss. We previously noted that low cyclosporine (CsA) levels were a risk factor for early acute rejection in pediatric recipients (1). In our current study, we used logistic regression to identify risk factors for acute rejection in 726 adult kidney transplant recipients on triple therapy (prednisone, azathioprine, CsA). Variables considered for logistic regression analysis were donor organ source (cadaver vs. living), degree of HLA mismatch (1 to 6 vs. 0 antigen mismatch), transplant number (primary vs. retransplant), CsA levels (< 125 vs. > or = 125 ng/ml, < 150 ng/ml vs. > or = 150 ng/ml, and < 175 vs. > or = 175 ng/ml), and acute rejection episodes (0 vs. > or = 1). Of 726 recipients, 401 (55%) received cadaver kidneys; 325 (45%), living related. Overall, 572 (79%) had a primary transplant; 154 (21%), a retransplant. The vast majority of acute rejection episodes occurred within the first 2 months posttransplant; 68% of recipients had no acute rejection episodes by 2 months and 58% had none by 60 months posttransplant. Logistic regression analysis revealed that a cadaver donor kidney (vs. living) (p = 0.004), a 1 to 6 antigen mismatch (vs. 0 mismatch) (p = 0.001), and CsA levels < 150 ng/ml (vs. > or = 150 ng/ml) correlated with biopsy-proven acute rejection. The correlation for CsA levels < 150 ng/ml (vs. > or = 150 ng/ml) held true for levels at 1 wk (p < 0.05), 1 month (p = 0.0001), 2 months (p = 0.01), and 3 months (p = 0.02) posttransplant. Similar correlation was found for CsA levels < 125 ng/ml (vs. > or = 125 ng/ml) and < 175 ng/ml (vs. > or = 175 ng/ml). Comparative analyses were made (by Chi-square) of acute and chronic rejection rates when recipients were divided into 3 groups by CsA level (< 125 ng/ml, > or = 125 to < 150 ng/ml, and > or 150 ng/ml). At each time point (1 wk, 2 wk, 1 month, 2 months, 3 months), CsA levels < 125 ng/ml (vs. > or = 125 to < 150 ng/ml and > or = 150 ng/ml) were associated with the greatest increased risk of acute rejection--for both cadaver and living related recipients (all p < 0.05). CsA levels < 125 ng/ml at each time point (1 wk, 2 wk, 1 month, 2 months, 3 months) were also associated with a significantly increased risk of chronic rejection (all p < 0.001). The incidence of both acute and chronic rejection was reduced in the group with CsA levels > or = 125 to < 150 ng/ml and further reduced in the > or = 150 ng/ml group. Our data indicate that maintaining CsA levels > or = 150 ng/ml as part of triple therapy reduces the incidence of both acute and chronic rejection. Because chronic rejection is the leading cause of late allograft loss, maintaining adequate CsA levels should improve long-term graft survival. Based on this analysis, we have modified our own immunosuppressive regimens to achieve higher CsA levels earlier posttransplant.

Effect of initial slow graft function on renal allograft rejection and survival

Cadaver renal allografts with immediate excellent function have good long-term outcomes, while grafts with delayed function have been associated with an increased incidence of acute rejection (AR) and subsequent poor long-term graft survival. There is, however, an intermediate group with initial slow function whose outcome is not well defined. This group was examined by reviewing 510 patients that received primary cadaver transplants between 1/85 and 8/95. Recipients were grouped by initial function into: 1) those with immediate graft function (IGF), defined by serum creatinine (Cr) level < 3 mg/dl on post-operative day (POD) 5 (n = 237); 2) those with slow graft function (SGF), defined by serum Cr > 3 mg/dl on POD 5 but no need for dialysis (n = 160); and 3) those with delayed graft function (DGF), defined by the need for dialysis in the first week post-transplant (n = 113). Five-year graft survivals were determined for each group by Kaplan-Meier methods and compared by a generalized Wilcoxon test. The incidence of AR in the first 6 months was significantly higher in those with SGF (40%) vs. those with IGF (30%) (p < 0.05); both groups had a lower incidence than those with DGF (47%) (p < 0.05). In the absence of AR, 5-yr graft survival was similar between the 3 groups, 94%, 97% and 92% for IGF, SGF and DGF respectively. In the presence of AR, 5-yr graft survival was significantly reduced in all groups, but most notably in those with SGF (51%) or DGF (53%), as compared to those with IGF (80%), (p < 0.001). We conclude that recipients with SGF, but no AR, have excellent outcomes, comparable to those with IGF. However, there is an increased incidence of early AR associated with SGF. In recipients with SGF or DGF, AR has a more profound detrimental effect on long-term graft survival than in the IGF group. Thus, recipients with SGF are at increased risk for AR with resultant poor long-term graft survival, and may need modified immunosuppressive protocols.

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.

Grandparent donors in a living related renal transplant program

Clinical renal transplantation is limited by the number of cadaver and living related donors. The use of kidneys from older donors and non-first-degree relatives, including grandparents, has increased the supply of organs for transplantation. The purpose of this study was to assess donor and recipient outcomes after living related renal transplants between grandparent donors and grandchild recipients. Fifteen living related renal transplants using grandparent donors were performed at the University of Minnesota from 1971 to 1995. All medical records from donors and recipients were retrospectively reviewed. In addition, all grandparents or, in one case, a surviving family member were contacted to obtain current information on medical health and feedback about the donation process. A current serum creatinine (Cr) level was obtained from 14 donors and 15 recipients. Statistical calculations were performed using the SAS system. Eleven grandmothers and four grandfathers, 34-70 yr old (mean, 55 yr) at the time of transplantation, donated a kidney to 15 grandchildren with end-stage renal disease. There were no major surgical complications in either group. One donor died from unrelated causes; the other 14 donors are alive with stable renal function (1.3 +/- 0.3 mg/dL). Of 15 transplanted kidneys, 10 remain functional (Cr 1.3 +/- 0.7 mg/dL) with 2- and 5-yr graft survival rates of 76% and 63%, respectively. Our results indicate that healthy grandparents provide an excellent population for living related kidney donation.

Complications by age in primary pediatric renal transplant recipients

We asked whether pediatric renal transplant recipients, subgrouped by age, differed in the percentage and number of hospital readmissions and in the incidence of infectious complications post transplant. Between 1 August 1985 and 31 October 1993, a total of 164 patients < 18 years of age underwent primary transplants, with cyclosporine-based immunosuppression, at the University of Minnesota. The percentage of readmissions (P = NS), the mean number of readmissions (P = NS), and the length of hospital stay during readmissions (P = NS) did not differ significantly among age groups. The overall incidence of acute rejection was greater in those > or = 2 years than those < 2 years (P = 0.002), and in living donor recipients > or = 2 years versus those < 2 years (P = 0.02). The incidence of bacterial infection (< 2 years, 87%; 2-5 years, 72%; 6-12 years, 51%; 13-17 years, 40%) was greater in younger recipients (P = 0.0001). The most common bacterial infection in recipients < or = 5 years was Clostridium difficile-associated diarrhea; in those > 5 years, urinary tract infection. The overall incidence of viral infection did not differ among groups (P = NS). The most common viral infection in recipients < or = 5 years was varicella and those > 5 years, cytomegalovirus infection. Risk factors for infection in the first 6 months post transplant included age < 2 years and Solu-Medrol treatment for acute rejection. In conclusion, young recipients < 2 years of age at the time of transplant are at a higher risk for bacterial infection post transplant.

Risk factors for prolonged hospitalization after kidney transplants

A major variable in the cost of kidney transplants is the length of initial hospitalization. Using multivariate analysis, we studied risk factors for hospital stay > 10 d post-transplant. Between 1 January 1985 and 31 August 1995 a total of 1588 patients underwent first or second kidney transplants at the University of Minnesota. Antibody was used for 1 wk in cadaver donor recipients and for 2 wk in pediatric recipients (resulting in a long stay for all pediatric recipients). Adult living related donor recipients were immunosuppressed with triple therapy. Donor risk factors studied were age (< 15, 15-50, > 50 yr) and,- for cadaver recipients, preservation time (< 12, 12-18, 18-24, 24-30, > 30 h) and cause of death (trauma, cerebrovascular accident, or cardiac). Recipient risk factors studied were age (< 18, 18-55, > 55 yr); sex; transplant number; antigen mismatch; peak PRA; PRA at transplant (< 11, 11-50, > 50); diabetic status; pretransplant dialysis (vs. pre-emptive transplant); pretransplant cardiac, peripheral vascular, or respiratory disease; and delayed graft function (DGF) (dialysis in the first week vs. no dialysis). Risk factors were analyzed separately for living donor and cadaver donor recipients. For cadaver donor recipients, DGF was the major risk factor (p < 0.0001); others were age 55 yr (p = 0.03) and diabetes (p = 0.02). For living donor recipients, DGF was also a risk factor (p = 0.003); others were diabetes (p = 0.01), retransplant (p = 0.006), PRA at transplant > 50 (p < 0.0001), age > 55 yr (p = 0.02), pretransplant respiratory disease (p = 0.005), and pretransplant dialysis (p = 0.005). Because DGF was the major risk factor for a prolonged stay, we then studied risk factors for DGF using multivariate analysis. For cadaver donor recipients, risk factors were recipient weight > 90 kg (p = 0.004), preservation time 24 h (p = 0.03), PRA at transplant > 50 (p = 0.03), and donor age < 15 or > 50 yr (p = 0.002). For living donor recipients, risk factors were recipient age < 18 yr (p = 0.01), donor age > 50 yr (p = 0.03), female sex (p = 0.05), pretransplant respiratory disease (p = 0.1), pretransplant peripheral vascular disease (p = 0.05), and recipient weight > 90 kg (p = 0.1). From our data, a profile emerged of recipients likely to have a longer hospital stay. Important variables, either simultaneous with or related to DGF, include donor and recipient age, diabetes, pretransplant recipient weight, PRA at transplant, preservation time, and pretransplant respiratory or peripheral vascular disease.

Risk factors for chronic rejection in pediatric renal transplant recipients--a single-center experience

Chronic rejection (CR) is the most common cause of graft loss beyond the 1st posttransplant year. The aim of this analysis was to identify the risk factors for the development of CR in pediatric renal transplant recipients. Between June 1984 and March 1994, 217 renal transplants were performed in children at our center. Immunosuppression included prednisone, azathioprine, cyclosporine (CsA), and prophylactic antibody. Using multivariate analysis, we studied the impact of the following variables on the development of biopsy-proven CR: age at transplant (< or = 5 years, > 5 years), gender, race, transplant number (primary, retransplant), donor source (cadaver, living donor), donor age (< 20 years, 20-49 years, > 49 years), number of ABDR mismatches (0, 1-2, 3-4, 5-6), number of DR mismatches (0, 1, 2), percentage peak panel reactive antibody (PRA) (< or = 50%, > 50%), percentage PRA at transplantation (< or = 50%, > 50%), dialysis pretransplant, preservation time > 24 h, acute tubular necrosis requiring dialysis, initial CsA dosage (< or = 5 mg/kg per day, > 5 mg/kg per day), CsA dosage at 1 year posttransplant (< or = 5 mg/kg per day, > 5 mg/kg per day), acute rejection (AR), number of AR episodes (ARE) (1, > 1), timing of AR (< or = 6 months, > 6 months), reversibility of AR (complete, partial), and infection [cytomegalovirus (CMV), non-CMV viral, bacterial]. Risk factors for the development of CR in pediatric renal transplant recipients were: AR (P < 0.0001, odds ratio 19.4), multiple ARE (> 1 vs. 1) (P < 0.0001, odds ratio 30.1), and high percentage peak PRA (> 50%) (P < 0.03, odds ratio 3.6).

Kidney transplantation: a brief review

Since the first successful kidney transplant in 1954, results of these transplants have dramatically improved. Given refinements in surgical techniques and perioperative care, combined with superior immunosuppression, the procedure is now the treatment of choice for patients of all ages with ESRD. Acute rejection no longer represents a significant threat to graft loss, and the newer immunosuppressive drugs will likely diminish this problem further. Complications such as sepsis are fewer and more reliably managed with current therapies. Chronic rejection remains a major problem whose incidence has not been significantly altered. This along with a better understanding of the processes that may ultimately lead to graft tolerance will be the major challenges facing the field of renal transplantation as it enters the 21st century.

Recurrence of haemolytic-uraemic syndrome in renal transplants: a single-centre report

BACKGROUND

The incidence of recurrence of haemolytic-uraemic syndrome (HUS) in renal allografts appears to vary by centre, with the highest rates reported from the University of Minnesota. It is possible that the high rate of HUS recurrence at this institution reflects a transplant population skewed towards patients with a form of HUS that is more likely to recur in the allograft.

METHODS

This study examined whether the initial episode of HUS in the native kidneys was preceded by a diarrhoeal prodrome ('classical HUS') or not ('atypical HUS'), and evaluated transplant outcomes in 24 patients who received 36 transplants at the University of Minnesota between 31 May 1972 and 31 December 1994.

RESULTS

Eighteen of the 24 patients had atypical HUS, three had classical HUS, and in three patients the presence or absence of a diarrhoeal prodrome could not be determined. Recurrent HUS, defined as microangiopathic haemolytic anaemia, thrombocytopenia, renal insufficiency, and allograft biopsy findings compatible with HUS, occurred 16 times in 14 grafts in 11 patients. Nine of these patients had atypical HUS, one had classical HUS, and in one the nature of the prodrome could not be determined. Eleven of the 14 initial recurrences took place within 2 months of transplant. Recurrence was not more frequent in patients who received cyclosporin or antilymphocyte preparations. Actuarial analysis using matched controls showed poorer graft survival in patients with a primary diagnosis of HUS (P = 0.007), due to the high frequency of graft loss in HUS patients with recurrence.

CONCLUSION

Based upon these data and a review of the literature, it can be concluded that the risk of recurrence of HUS in the allograft is confined almost entirely to patients with atypical forms of HUS.