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J M Cecka

Publications and source records attributed to J M Cecka.

At least 37 records · Page 2Linked to original sources
PubMed1998

Transplantation of kidneys from donors whose hearts have stopped beating.

BACKGROUND: Attempts have recently been made to expand the number of cadaveric kidneys available for transplantation by using kidneys from donors without heartbeats in addition to those from brain-dead donors with beating hearts. We studied the efficacy of transplanting kidneys from donors without heartbeats on the basis of aggregate results from the Kidney Transplant Registry of the United Network for Organ Sharing. METHODS: We compared the early function and survival rates of 229 kidney grafts from donors without heartbeats with those of 8718 grafts from cadaveric donors with heartbeats. All transplantations were performed at 64 U.S. transplantation centers. Cox proportional-hazards analysis was used to evaluate 10 major risk factors for graft failure. RESULTS: The survival rate at one year was 83 percent for kidney grafts from donors without heartbeats, as compared with 86 percent for grafts from donors with heartbeats (P=0.26). Among the kidneys from donors without heartbeats, the survival rate at one year was 89 percent for grafts from donors who had died of trauma, as compared with 78 percent for grafts from donors who had died of other causes (P=0.04). The survival rates were high for grafts from donors without heartbeats despite the poorer early function of these grafts; 48 percent of the recipients required dialysis within the first week after transplantation, as compared with 22 percent of the recipients of grafts from donors with heartbeats. The primary-failure rate for kidneys from donors without heartbeats was 4 percent, as compared with 1 percent for kidneys from donors with heartbeats. CONCLUSIONS: Transplantation of kidneys from donors whose hearts have stopped beating, especially those who have died of trauma, is often successful, and the use of kidneys from such donors could increase the overall supply of cadaveric kidney transplants.

Brain Death↗
PubMed1998

The UNOS Scientific Renal Transplant Registry.

Based on analyses of kidney transplants reported to the UNOS Scientific Renal Transplant Registry from 1991-1997: 1. The 5-year patient and graft survival rates were 82% and 63%, respectively, for 50,291 recipients of cadaver donor kidneys and 90% and 77%, respectively, for 20,258 recipients of living donor transplants. 2. Black recipients had 12% lower 5-year graft survival rates than Whites whether the kidney was from a cadaver donor (n = 11,575) or a living donor (n = 2,806). 3. The survival rates of second transplants were only 2% less than first transplants, whether the kidney was from a living or cadaver donor. The one-year regraft survival rates for multiply retransplanted patients were 77% and 87% for cadaver and living donor retransplants, respectively. 4. Graft survival rates were 5-6% lower among broadly sensitized recipients (> 50% PRA) than unsensitized (< 10% PRA) recipients, regardless of the donor source. 5. The average recipient aged between 1991-1997. The mean age increased from 42-46 years for cadaver kidney and from 34-40 years for living donor transplant recipients. 6. The percentage of older donors also increased during 1991-1997. The proportion of cadaver kidneys from donors over age 45 rose from 24% in 1991 to 33% in 1997. The percentage of living donors over age 45 increased from 23% in 1991 to 29% in 1997. 7. There was a 25% difference in 5-year graft survival rates comparing recipients of kidneys from 19-30 year-old cadaver donors with those who received kidneys from donors over age 60. Recipients of kidneys from living donors over age 60 had an 8% lower 5-year graft survival rate than when the donor was aged 19-30. 8. Among recipients of cadaver kidneys, the incidence of delayed graft function increased from 17% when the donor was aged 15-20 to 40% when the donor was over 65. DGF reduced one-year survival rates by 10% and half-lives by 2 years when grafts from 19-30 year old donors and donors older than 55 were analyzed separately. Cold ischemia time also resulted in increased DGF, from 17-39% for CIT up to 49-72 hours. However, when the donor was aged 19-30, DGF ranged from 12-30% and when the donor was over 60, DGF increased from 33-68% with longer CIT. 9. Rejection episodes before the initial hospital discharge resulted in a 10% reduction in 5-year graft survival rates regardless of the donor source. 10. The degree of HLA compatibility between the donor and recipient was associated with a 12% difference in 5-year graft survival rates among recipients of cadaver kidneys. The survival difference was 11% among recipients of living-related donor kidneys, but there was no difference in the survival of one- and 2-haplotype disparate grafts. Similarly kidneys transplanted from distant relatives and from unrelated donors with poor HLA compatibility resulted in survival rates that were not distinguishable from HLA-mismatched related donor kidneys.

Adolescent↗
PubMed1998

Flow cytometry crossmatching (FCXM) in the UNOS Kidney Transplant Registry.

1. Among 5,776 transplants reported to the UNOS Scientific Renal Transplant Registry with flow cytometry crossmatch (FCXM) results, 13% had a positive FCXM. The majority (8.8%) had B-cell only reactivity and the remaining 4.2% had T-cell reactivity. 2. Retransplanted patients, females and sensitized patients were more likely to have been FCXM positive than primary transplants, males, or unsensitized patients. 3. A positive FCXM was associated with less than optimal function as evidenced by an increased need for posttransplant dialysis, more grafts that never functioned, longer hospital stays and a higher incidence of rejection. 4. The impact of antibodies detected by FCXM on graft survival was strongest among retransplanted patients (60% 3-year graft survival with a positive FCXM vs 79% with a negative FCXM, p = 0.003), although significant differences were also noted in primary transplants (76% 3-year graft survival with a positive FCXM vs 81% with a negative FCXM, p < 0.001). Class I reactivity generally had a greater impact on survival, although class II antibodies had a deleterious effect as well. 5. Primary transplants across a T+B+ FCXM (n = 187) had a 76% 3-year graft survival rate compared with 74% for 509 T-B+ transplants. Both were significantly lower than the 81% 3-year graft survival rate for 5,017 T-B- FCXM transplants. 6. Retransplants across a T+B+ FCXM (n = 48) had a 60% 3-year regraft survival rate compared with 73% for 118 T-B+ regrafts and 79% when the FCXM was negative when tested against both targets (T-B-, n = 698). 7. Although there is room for improvement in the technique, the FCXM continues to be effective in identifying kidney transplants at risk of early graft failure and of rejection.

B-Lymphocytes↗
PubMed1998

Impact analysis: a method for evaluating the impact of factors in clinical renal transplantation.

Impact analysis, showing the proportion of patients in each category, is useful in providing a rapid visualization of the current renal transplant situation. It provides a 2-dimensional view of the number of cases and the success rates of each category. From the graphs, one can readily see the impact of changing policies upon overall results. Efforts to reduce cold ischemia time and increase zero HLA-A, -B, -DR mismatched transplants would have a significant impact. Clearly, the greatest adverse impact factor in cadaver kidney transplants today is donor age: transplants from donors aged 40 and older negatively impact current overall success rates.

Cadaver↗
PubMed1997

The great success of Asian kidney transplant recipients.

BACKGROUND: Little has been written about allograft survival in non-African-American minority groups. We examine the success of kidney transplantation in 1900 Asian recipients. METHODS: Data from 42,252 cadaveric and 16,115 live donor kidney transplant recipients were monitored from the United Network for Organ Sharing Scientific Renal Transplant Registry from 1991 through 1996. RESULTS: Asian recipients exhibited the highest cadaveric allograft survival rates (89% 1-year and 83% 3-year survival) and the longest mean allograft half-life (18 years). Asian women had the highest mean graft half-life (23 years). Asians were less likely to be broadly sensitized and had a high incidence of IgA nephropathy causing end-stage renal disease. Although it has been suggested that their low body weights may help explain the excellent allograft outcome, Asians exhibited superior graft survival rates even when compared with low body weight recipients of other races. CONCLUSION: Asian renal allograft recipients, particularly Asian females, have the highest allograft survival rates of all racial groups.

Adult↗
PubMed1997

Effect of HLA matching on the relative risk of mortality for kidney recipients: a comparison of the mortality risk after transplant to the mortality risk of remaining on the waiting list.

BACKGROUND: Patients must wait increasingly longer periods on the kidney waiting list (WL) before receiving a transplant. Although patients can be maintained on dialysis, many deaths occur while waiting. To determine whether the risk of mortality on the WL is different from that related to the transplant procedure, data from the Organ Procurement and Transplantation Network and Scientific Registry were used to analyze all adult patients entered on the United Network for Organ Sharing (UNOS) kidney WL for a primary transplant between April 1, 1994, and December 31, 1994 (n=9925). METHODS: To account for the time spent on the WL before transplant, a time dependent, nonproportional hazards model was used to assess the risk of mortality after transplant for both well-matched (zero to two HLA mismatches) and poorly-matched (three to six HLA mismatches) transplants compared with the mortality risk of remaining on the WL. This model incorporated an exponential decay component to account for the transient increased risk after kidney transplantation. Patients were stratified by age, race, creatinine level, panel-reactive antibody at listing, and blood group. RESULTS: Although there was an increased risk of mortality in the initial posttransplant period, the risk of mortality at 1 year for transplanted patients was 59% (three to six mismatches) to 67% (zero to two mismatches) less than that of patients who remained on the waiting list for an additional year. CONCLUSIONS: Kidney transplantation is more beneficial than remaining on the waiting list. Even poorly-matched kidneys provided a significant reduction in the risk of mortality by 6 months as compared with the mortality risk of continuing to wait. Patients receive the maximum benefit when transplanted with well-matched kidneys.

Adult↗
PubMed1997

Unrelated living donor kidney transplants.

Due to the shortage of cadaver donor kidneys in the US, an increasing effort has been made to supplement the donor supply with transplants from unrelated living donors (URLD). In the present communication, we wish to update the URLD results from the United Network for Organ Sharing (UNOS) Kidney Transplant Registry. Since we last published the results, the number of such transplants has more than doubled.

Family↗
PubMed1997

Pediatric renal transplantation: a review of the UNOS data. United Network for Organ Sharing.

The UNOS Scientific Renal Transplant Registry data from October 1987 to December 1996, including information on transplants to 537 patients aged 0-2, 2399 patients aged 3-12 and 5986 patients aged 13-21, were used to examine the results of pediatric transplantation by both univariate and multivariate methods. One-year and long-term graft survival rates were adjusted for 9 covariates including donor source and age, recipient sex, race and disease, and transplant year, HLA mismatches, and transplant center. The adjusted 1- and 5-year graft survival rates were 71% and 60% for ages 0-2, 83% and 64% for ages 3-12 and 85% and 57% for ages 13-21. Except for the youngest recipients, these results compared favorably at 1 year with 86% graft survival among 78,418 adults. The projected graft half-life was highest in patients under age 2 (18 years) and lowest among teenagers (7 years) compared with adults and children (11 years). Univariate analyses revealed a significant 10% graft survival advantage with living donor kidneys for all age groups, but especially for those aged 0-2 in whom survival was 66% with a cadaver donor and 84% with a living donor. The youngest recipients experienced early rejection of the mother's kidney less often than the father's (47% vs 28% in the first 6 months, p<0.007). Results in blacks were similar to those in whites during the first year, but the 3.8 year half-life for black teenagers was the lowest among all groups. We conclude that with the exception of very young (age 2 or under) patients, 1-year pediatric renal transplant survival rates are comparable to those in adults, but in the long term, non-compliance and late acute rejection result in an accelerated graft failure rate among teenagers.

Adolescent↗
PubMed1997

Significance of the donor age effect on kidney transplants.

The shortage of cadaveric donor kidneys for transplantation has forced a re-evaluation of the limits on donor age acceptability. However, as more kidneys from older donors have been transplanted, a significantly lower graft survival has been noted among their recipients. The impact of utilizing older donor kidneys and the relative importance of donor age with respect to other factors has not been clarified. A total of 43,172 cadaver donor transplants reported to the UNOS Scientific Renal Transplant Registry between 1987 and 1995 were the subjects of this study. Cox regression analysis was utilized to assess the joint effects on graft survival of donor age and HLA mismatch, recipient sex, race, age, original disease, donor death cause, cold ischemia time, and transplant year. Increased first day anuria, dialysis requirement, and discharge serum creatinine were noted with increasing donor age. Moreover, long-term graft and patient survival diminished as donor age increased. The 5-yr graft survival of zero HLA-A,B,DR mismatched kidneys fell steadily from 81% when the donor was aged 21-30 to 39% when the donor was over age 60. The reported causes of kidney transplant failure were remarkably similar for old and young donors. The best transplant results were obtained with zero HLA-A,B,DR mismatched transplants from young donors and the worst with older donor kidneys, regardless of HLA compatibility. We calculated that up to 21% of kidney failures resulted from insufficient renal mass due to age and were incorrectly attributed to chronic rejection.

Adolescent↗
PubMed1997

The UNOS Scientific Renal Transplant Registry--ten years of kidney transplants.

1. The number of kidney transplants reported to the UNOS Scientific Renal Transplant Registry (excluding multiorgan transplants) increased from 8,831 in 1988 to 10,204 in 1996, mainly due to increased donation by living donors (1,812-3,149 during the same period). 2. Overall projected 10-year primary graft survival rates were 73% for 3,515 recipients of HLA-identical sibling grafts, 55% for 16,160 recipients of other living donor transplants or 3,940 HLA-matched cadaveric grafts and 39% for 50,900 recipients of HLA-mismatched cadaver donor kidneys. 3. One-year first cadaver graft survival rates improved from 77% in 1988 to 87% in 1997 and graft half-lives improved from 7.6 years for 1988 transplants to 11.6 years for 1994 transplants. 4. Improving graft survival rates were associated with a modest 2% increase in one-year patient survival and a projected 13% increase at 10 years. Better patient survival may contribute to rising long-term graft survival rates. 5. Immunosuppression has also played an important role as the incidence of rejection episodes within the first 6 months decreased from 52% in 1988 to 24% in 1996 and immunological graft failures declined in 1995 and 1996 accounting for less than 30% of first year graft losses. The majority of first year graft losses were due to patient deaths for the first time in 1995. 6. A major change in maintenance immunosuppression occurred in 1996 when about 60% of first cadaver transplant recipients received Neoral, MMF and prednisone (NMP) at the time of hospital discharge. Preliminary results show a 90% one-year graft survival rate with NMP compared with 87% for CsA- and FK-based immunosuppression. Improved long-term graft survival that had been previously noted in patients treated with FK506 was not apparent in the 1994-96 cohort analyzed. The use of induction with OKT3 or ALG reduced rejection episodes during the initial transplant hospitalization but did not affect one-year or long-term graft survival. 7. There has been a significant improvement in immunological high-risk patients. The results of second transplants trailed those of primary grafts by only 3% in the 1994-96 period compared with a 6% difference in 1988-90 and recently retransplanted patients who were not broadly sensitized had the same graft survival rate as unsensitized first transplant recipients. Recipients of poorly HLA-matched kidneys also had significantly improved survival rates during 1994-96. The 3-year survival difference between recipients of kidneys with only one or 2 HLA mismatches and those with 5-6 mismatches was 4% compared with 8% for comparably matched recipients transplanted in 1988-90. 8. The 3-year graft survival rate for Black recipients was 57% in 1988-90 and 67% in 1994-96. The gap between Blacks and Whites narrowed from a 9% 2-year survival rate difference in the early cohort to 5% in the more recent transplants. Asians transplanted in 1994-96 had a superior graft survival rate of 90% at one year with an 18-year half-life. 9. Despite a substantial increase in the number of living donor transplants performed in recent years, graft survival rates were still superior to all but the best HLA-matched cadaver transplants. Most of the additional living donor activity has involved HLA-mismatched pairs with a 3-fold increase in the number of completely HLA-mismatched transplants (513 in 1988-90 vs 1,583 in 1994-96). The one-year graft survival rates were 96%, 93% and 92% for HLA-identical, one- and 2-HLA haplotype disparate transplants, respectively.

Cadaver↗
PubMed1997

Strategy for eliminating the kidney shortage.

1. We anticipate that the number of kidneys from conventional heart beating donors who are under age 55 will remain stable at about 8,000/year. A natural increase of donors over age 55 and living donors is expected to increase the total transplants from about 12,000 today to 14,000 in 8 years. 2. We propose a 4-year acceleration phase, during which older cadaver donors, related and unrelated living donors will be increased to a maximum of 4,000 in the 4th year. This acceleration is a temporary one, and will be reduced to zero over 4 subsequent years. 3. An increase in NHBD will be encouraged at a rate of 700/year, so that at the end of 14 years, they would constitute about 10,000 cadaver donor kidneys. As can be seen in Figure 1, at this rate, NHBD kidneys will first replace the accelerated effort, then replace the living donors and eventually the older heart beating donors. With the abundance of kidneys, it is likely that many patients who are not listed today would be encouraged to become transplant candidates. Moreover, patients needing retransplants will increase. However, once this capacity is developed, any increases in new transplant candidates could be accommodated. Thus in 14 years, there will be about 18,000 kidneys available each year. Approximately 60% will be NHBD and 40% heart beating donors, with no living donors and no older donors and no need of pig donors. We will be in transplant nirvana.

Cadaver↗
PubMed1997

Spousal and other living renal donor transplants.

Aside from HLA identical sibling donors, spousal donor transplants are the best living donors because their 3-year graft survival is comparable to that of all other living donors--with the exception of HLA identical siblings. Interestingly, the 14.5 year half-life of spousal donor kidneys was superior to the 10.8 year half-life of other living donor transplants. Better quality kidneys is the principal explanation for higher spousal donor graft survival rates when compared with cadaver donors. This was evident from the 2% anuria rate in the first post-operative day for spouse donor compared with 10% of cadaver donor transplants. Moreover, the requirement for dialysis was 6% for spouse donor grafts compared with 22% of cadaver donor transplants. The damage is not attributable to cold ischemia time but rather to agonal events and shock prior to kidney harvesting. In a survey of 176 spousal renal transplant donors, 175 of 176 said they would advise others to donate a kidney to a spouse--and only one donor advised against it. Of the "yes" responses, 28% provided additional comments enthusiastically recommending it. About 47% reported improvements in the marital relationship, 29% in the sexual relationship, and 25% described improved relations with their children. The fact that the donor reaps many direct personal benefits should make spousal donation the first consideration for living-donation (after the HLA-identical sibling donor).

Adolescent↗
PubMed1997

Clinical aspects of sensitization.

1. The incidence of broad sensitization has decreased significantly over the past 8 years, probably due to a decrease in pretransplant blood transfusions. Graft survival rates among broadly sensitized patients have improved over this time period (76% graft survival at 2 years posttransplant for patients transplanted in 1995-1996 compared with 66% for patients transplanted in 1989-1990). This is probably due to an improvement in immunosuppression and a related decrease in the incidence of acute rejection episodes. 2. As has been shown before, blood transfusions, previous pregnancies and failed allografts independently increased the incidence of sensitization. It is clear that certain subgroups of patients are more likely to become sensitized, given antigenic stimulation, as evidenced, for example, by the fact that 52% of patients receiving more than 10 units of blood prior to transplant were relatively unsensitized. Males seem to be less apt than nulliparous females to become broadly sensitized, although this may be due to the lower age of nulliparous females. Asians are the least likely race to become broadly sensitized. Among multiparous Asians who received more than 5 units of blood, 27% were broadly sensitized compared with 35% of comparable Whites and African Americans. 3. The incidence of acute rejection episodes increased with increasing degrees of sensitization. About 46% of first cadaveric allograft recipients with PRA levels greater than 50% had at least one acute rejection episode within 6 months after transplantation compared with 38% of unsensitized individuals. In addition, sensitized individuals were more likely to have an episode of early acute rejection before discharge from the hospital. 4. Induction with antilymphocyte antibody preparation was more commonly used in broadly sensitized patients. However, this therapeutic modality did not reduce the incidence of rejection episodes measured at 6 months posttransplant. In addition, the use of induction therapy for broadly sensitized patients has decreased with the advent of newer immunosuppressive protocols that include Neoral, MMF and FK506. 5. There was an association between the incidence of broad sensitization and delayed graft function. Induction therapy was more commonly used in patients with both delayed graft function and broad sensitization, although the decision to use this therapeutic modality seems to be made based on the presence of broad sensitization rather than the presence of delayed graft function. 6. Choosing the optimal immunosuppressive drug regimen is an important decision in broadly sensitized individuals because of the increase in acute rejections and decrease in overall graft survival in this group. Classic teaching suggests that this group of patients should be administered induction therapy with antilymphocyte antibody preparations. Early data suggests, however, that the combination of Neoral, mycophenolate and prednisone may be the optimal regimen for these individuals with respect to graft survival and that the addition of antibody induction therapy to any of the other commonly used regimens does not improve graft survival (at least up to 3 years after transplantation).

Blood Transfusion↗
PubMed1997

Effect of delayed graft function on short- and long-term kidney graft survival.

Delayed graft function (DGF) has been identified as a predictor of poor long-term graft survival, but whether its effects are independent of rejection or final serum creatinine level is controversial. Based on the results of 57,025 first cadaver transplants reported to the UNOS Registry, we showed that: 1. Early acute rejection significantly lowered one-year graft survival rates by 8-9% in kidneys with early function (EF) (89% vs 80%; p < 0.001) or with DGF (72% vs 64%; p < 0.001). 2. DGF significantly lowered short- and long-term graft survival in patients without rejection (EF-1-yr graft survival rate of 89%, t1/2 of 9.5 years vs DGF-72% 1-yr graft survival rate, t1/2 of 6.7 years; p < 0.001). 3. Even when the discharge serum creatinine level was < 2.0 mg/dl with no rejection, DGF lowered graft survival (EF-1-yr graft survival rate of 93%, t1/2 of 10.4 years vs DGF-90% 1-yr graft survival rate, t1/2 of 7.6 years; p < 0.001). 4. Acute rejection, elevated discharge serum creatinine level (2-6 mg/dl) and older donor age (46-60 yrs) each lowered one-year graft survival rates in a stepwise fashion. There was exceptionally poor graft survival of kidneys from donors aged 46-60 with DGF, whether or not early acute rejection was present (with rejection-1-yr graft survival rate of 61%, t1/2 of 5.6 yrs vs no rejection-1-yr graft survival rate of 71%, t1/2 of 5.3 yrs). 5. Increasing cold ischemia time only decreased graft survival when there was no DGF and no rejection and had no significant effect on long-term graft survival. 6. Among recipients of HLA-matched cadaver kidneys, DGF lowered short- and long-term graft survival, even in the absence of early rejection (EF-1-yr graft survival rate of 93%, t1/2 of 14.8 yrs vs DGF-1-yr graft survival rate of 76%, t1/2 of 7.8 yrs). 7. DGF was associated with higher rates of acute rejection but impaired long-term graft survival even when rejection was absent and discharge creatinine was normal. These data support the hypothesis that DGF leads to an injury response that can reduce graft survival through antigen dependent and antigen independent mechanisms.

Adult↗
PubMed1996

Fit and match hypothesis for kidney transplantation.

The importance of HLA matching for cadaver-donor transplants is often ignored due to the small (10%) difference in graft survival rates between the best and worst matched pairs. A new "fit and match" hypothesis is proposed to improve the predictive value of matching. Graft and functional survival rates of kidney transplants were calculated for living and cadaver-donors by the standard Kaplan and Meier methods. Mean discharge serum creatinine (SCr) values were computed after excluding patients who died or lost their grafts before discharge. Donor size, recipient size, age of donor kidney, damage caused by cold ischemia time, and mode of donor death all had substantial effects on the average SCr levels at discharge. These SCr levels correlated with one- and five-year graft survival rates. Transplants that had extremely different graft survival rates, such as those from living donors and cadaver donors, were found to have similar rates when reclassified by SCr levels at discharge. By examining the combined effects of the fit and match factors, transplants with the best fit and match exhibited a 95% one-year graft survival rate, whereas those with the worst fit and match had a 75% survival rate. This 20% difference increased to 36% after five years (84% vs. 48%). We conclude that the fit and match hypothesis provides a theoretical basis for devising a more critical method of predicting cadaver kidney transplant survival rates. Furthermore, it suggests a vital need to develop methods for estimating functional donor renal mass.

Age Factors↗