Management of the sensitized cardiac recipient: the use of plasmapheresis and intravenous immunoglobulin.

Previously, we reported that the combination of plasmapheresis (PP) and intravenous immunoglobulin (IVIg) allow sensitized patients to undergo orthotopic heart transplantation (OHT), even across a positive crossmatch. In the current study, the effect of that combination, PP+IVIg, on survival of a larger group of such recipients is investigated. The latter group (I) consisted of 35 sensitized patients who received PP+IVIG together with standard immunosuppressive drugs. Rejection was seen in 11 patients, findings strongly suggestive of a vascular (humoral) being identified in five of those cases. Four deaths occurred, two of them in the immediate post-operative period, one after almost six months, and one after almost two yr post-OHT. Follow-up range 4.5 months to 7.8 yr post-OHT (average=1.1 yr). Patient survival was analyzed after generation of a Kaplan-Meier plot. Comparison with a control OHT group (II) given standard immunosuppressive drugs only (N=276) showed enhanced survival of group I (p=0.0414 by log-rank test). We conclude that the combination of PP and IVIG (i) is associated with declines in T- and B-percent-reactive antibody and in crossmatch positivity, and (ii) is very useful in the management of the sensitized cardiac patient undergoing OHT, often allowing a successful outcome to transplantation in the face of a positive crossmatch.

Risk of early renal allograft failure is increased for patients with antiphospholipid antibodies.

Renal allograft thrombosis can cause transplant failure. Because antiphospholipid antibodies (aPA) are associated with thrombosis, we investigated pretransplant sera from patients with early renal allograft failure to determine if aPA were present. Fifty-six final cross-match (FxM) sera from patients whose transplant failed within 16 days were compared to FxM sera from the next sequential transplant patients. The sera were tested for IgG, IgM, and IgA antibodies to cardiolipin, phosphatidylserine, and phosphatidylethanolamine. aPA were identified in 57% of FxM sera from patients with early non-function versus 35% of FxM sera from patients with functioning grafts (P = 0.02). Historical sera from 11 aPA-positive patients contained aPA up to 18 months prior to transplantation. Since aPA were present in historical sera, testing for aPA can identify certain patients at risk for early allograft failure. The involvement of aPA in early allograft loss is supported by studies demonstrating aPA recovery from an explanted failed transplant.

Antiphospholipid antibodies are a risk factor for early renal allograft failure.

BACKGROUND: Biopsy specimens of transplanted kidneys that fail to function reveal cellular infiltrates, infarcts, and thrombi. Because antibodies to phospholipids (aPA) and/or phospholipid-binding proteins have been associated with thrombosis, we asked whether aPA are a risk factor for early allograft failure. METHODS: Final crossmatch sera from 56 patients with primary nonfunctioning renal allografts were tested for aPA. Serum from the next consecutive patient to undergo transplantation served as transplantation controls. Both groups were compared with aPA values obtained from testing 252 control individuals. The ELISA was designed to detect IgG, IgM, and IgA antibodies to phosphatidylserine, cardiolipin, and phosphatidylethanolamine. RESULTS: Patients were evaluated based upon the aPA ELISA findings. aPA were present in 57% of the patients with early nonfunction renal allografts and 35% of the patients with functioning grafts (P=0.0234). aPA in previously hemodialyzed patients did not predict allograft failure or success (P=0.3766). In contrast, all nonhemodialysis patients who had aPA at the time of transplantation experienced early allograft failure (P=0.0022). CONCLUSIONS: These data show that aPA are an important risk factor for early renal allograft failure. Furthermore, aPA-positive patients who have no history of hemodialysis are at the greatest risk. Pretransplantation aPA screening of renal transplant candidates forewarns of early graft failure and indicates which patients may benefit from anticoagulant therapy.

The LifeLink Foundation and cadaver kidney transplantation in Tampa.

1. LifeLink Foundation, a not-for-profit organization, has been the driving force and absolutely essential entity for kidney and liver transplantation in Tampa providing all the components (patient, organs and clinicians) save for inpatient hospitalization. It also plays a big role in the heart transplant program. LifeLink has increased the kidney transplant rate from the first 1,000 done in 17 years to the second 1,000 in 7 years and is on a pace for the third 1,000 in 5 1/2 years. 2. Because of its innovative programs, cadaver donor procurement by the Tampa LifeLink OPO has been roughly double the national average for the past 10 years. Because of cadaver kidney availability the median wait time from activation on the wait list to transplantation over the past 5 years was 159 days. The recent transplant rate is 14.7-22.7% higher than the national average, dependent upon the parameter measured. Similar results are seen for Tampa patients awaiting heart and liver transplantation. 3. The overall outcome of 1,184 cadaver kidney transplants performed in the decade 1989-98 was similar to that reported from the UNOS database in this series of publications. a) One- and 2-year graft survival increased 2% per year over the decade with a recent one-year graft survival rate of 96%. The overall T1/2 was 10 years. b) Our disastrous 1994 results were quickly reversed by a more intense pretransplant medical evaluation, the introduction of mycophenolate mofetil, more aggressive and earlier treatment of rejection episodes, and mandatory T- and B-cell flow cytometry crossmatching for all transplants. The incidence of rejection episodes decreased from 40 to 20%, and the first year immunological graft loss decreased from 5%, to 1.9%, to 0.8%, to 1.4% and 0% over the succeeding 4 years. 4. Individual factors affecting allograft survival were strikingly similar to national data, although all did not react statistical significance probably due to the smaller numbers. a) Primary and second grafts had similar survival rates (p = 0.97) whereas the third or subsequent graft survival was 7-32% poorer (p = 0.02). b) Black recipients had survival rates 10-13% lower than Caucasians and other races (p = 0.003). c) Patients with a peak PRA > 50 had survival values 4-13% poorer than those with < 50 PRA (p = 0.14). d) Patients with 2-4 HLA mismatches had graft survival rates 4-10% poorer than those with 0-1 mismatch (p = 0.12), whereas those with 5-6 mismatches had rates 6-17% poorer (p = 0.04). e) Although 22% of our transplants were to patients > 60 years of age, there was no difference (p = 0.81 to 0.90) in graft survival for the age groups 0-40, 41-60 and > 61. However, the proportion of grafts lost due to patient death compared with all allografts lost, was very different at 21% in the youngest group, 43% in those 41-60 years of age, and 63% in recipients > 61 years. 5. The rate of delayed graft function with imported kidneys was higher (27 vs. 16%, p = 0.006) but essentially the same as local kidneys with the same ischemia times. However, 41% of local kidneys were transplanted within 12 hours of procurement. Totally, 78% of local kidneys were transplanted within 18 hours (11% DGF rate) versus 79% of imports being transplanted at > 18 hours (32% DGF rate). Ischemia time, not the kidney source is the key issue since: a) There was no difference in overall graft survival of imported versus local kidneys (p = 0.95) nor in comparing local versus import kidneys with (p = 0.66) or without (p = 0.69) DGF. b) There was, however, a 11-17% overall poorer graft survival over 3 years in kidneys with DGF (p < 0.001) seen with both local (9-18% poorer, p = 0.0002) and imported (12-19% poorer, p = 0.008) kidneys. c) Kidneys displaying DGF came from older donors (40 vs. 34 years, p = 0.023) and had longer ischemia times (21 vs. 15 hours, p < 0.0005). 6. Dual kidney transplants were started in late 1996 with older or marginal donors to provide a better chance of success fo

Flow cytometry crossmatching and primary cadaver kidney graft outcome: relevance of T and B cell targets, historic sera and autologous controls.

There is limited information regarding the role of flow cytometry crossmatching (FCXM) in primary cadaver kidney allografting and even less about B cell reactivity and graft survival (GS). Furthermore, there is little or no published data concerning reaction strength (cutoff value), the effect of historic sera reactions, and the usefulness of performing autologous crossmatches (XMs) on GS. These factors were examined retrospectively on 214 primary transplants performed from August 1991 to January 1994 with follow-up to July 1995. Three-color FCXMs were done on a 1024-channel BD-FACScan, and the shift in median channel fluorescence (MCF) over the negative control was calculated. All patients had a negative T cell (AHG) and warm B cell (2 was, extended incubation) cytotoxicity XM, and none was excluded in calculating GS. A quantitative effect was noted as stronger MCF shifts vs. T or B cells correlated with decreased GS (r = 0.98 and 0.92, respectively). Significant differences were seen with cutoff values of T = 50 and B = 110 which were 1.7-1.8 times the SD above the mean MCF of normal sera controls T neg patients (n = 198) and 1- and 3-yr actuarial GS of 86% and 79% compared to T pos patients (n = 16) of 75% and 49%, p = 0.008. B neg patients (n = 177) had 1- and 3-yr GS od 86% and 81% compared to B pos patients (n = 37) of 78% and 47%, p = 0.005. Most informative was the analysis of combined T and B cell FCXM results. Three years GS for T neg - B neg patients (n = 171) was 81% and for T pos - B neg patients (n = 6), it was 83%, p = 0.98. The 27 T neg - B pos group's GS was lower at 62% but did reach significance. Poorest GS was seen for T pos - B pos patients (n = 10) at 23%, p = 0.0001. Reaction patterns showed that T cells detected only HLA Class I antibodies, whereas B cells detected both Class I and II. Historic sera (> or = 1 month old) reactivity influenced GS. Patients with > or = 2 past sera positive but current serum negative reactions vs. T or T plus B cells (n = 7) had a poor 29% GS, while those historically positive only vs. B cells (n = 7) had 100% GS. On the other hand, patients positive only with the current serum (n = 16) had 2-yr GS of 100% (false positive test?), while patients whose current and historic sera reactions were positive (n = 21) had a 25-50% GS (true positive test?). About 1 in 15 patients (19%) displayed positive autologous FCXM reactions. Subtraction of autologous MCF shift values from those vs. the donor converted 17 patients to the T neg - B neg or T pos - B neg group whose 2-yr actual GS was not significantly different (p > 0.8) from those initially testing T neg B neg vs. their donors.

Hemoconcentration prior to serology testing in hemodiluted cadaver bone and tissue donors.

Concern about false negative serology tests for infectious diseases in hemodiluted cadaver donors resulted in issuance of new regulations and guidelines from the FDA and CDC. Bone or tissue from donors receiving > or = 4 units of blood, blood products, colloids or crystalloids within 48 h of sampling must be quarantined unless: (a) a pretransfusion serum is available; or (b) an adequate algorithm is employed to ensure hemodilution is insufficient to alter test results, i.e. cause false negatives. Left undefined in these regulations is, what is an adequate algorithm and what amount of hemodilution would cause false negatives. A pretransfusion sample was not available for about 20% of our donors and many had incomplete infusion histories. We used the unambiguous quantitation of serum albumin and total protein to define hemodilution and, if present, hemoconcentration of sera by ultrafiltration to normal protein levels prior to serology testing. Control experiments showed excellent correlation between serum dilution and protein concentration (r > 0.99) and a quantitative recovery of 96.9 +/- 1.4% upon hemoconcentration. Known positive sera (CMV-Ab; HTLV-1Ab; HIV-1,2Ab; HBsAb; HCV-Ab; HBsAg) were spiked into normal sera and diluted up to 1:2000, well beyond detectable levels. A qualitative recovery of 100% and a quantitative recovery of 97.6 +/- 7.5% of antibody or antigen reactivity was achieved upon hemoconcentration and retesting. In two studies, 14% (30/210) and 43% (23/54) of cadaver donors had serum proteins below normal limits and their sera was hemoconcentrated.(ABSTRACT TRUNCATED AT 250 WORDS)

Positive crossmatches against mandatorily shared kidneys.

From October 1987 through February 1990 approximately 8.5% (29/341) of all donor kidneys shipped under the UNOS Mandatory Sharing Policy were denied to 27 intended recipients due to a positive final crossmatch [XM(+)]. The intended recipients included 18.5% hispanics and 7.4% blacks compared to 2.4% and 1.6%, respectively, for XM(-) recipients (1-3). Further, more were highly sensitized with 81% having a current PRA greater than 10% and 56% with a peak PRA greater than 80% compared to 65% and 14%, respectively, for XM(-) recipients. More importantly, 19/27 (70%) of the recipient candidates may have had irrelevant positive XMs. The XM(+) patients were classified into five categories defined by: I) autoantibodies; II) transfusions in the 2 weeks prior to the availability of the donor; III) the XM technique; IV) highly sensitized regraft candidates with current and peak PRAs greater than 85% and V) antibody to unreported MHC antigens. Of these, 70% may have been denied a transplant due to IgM autoantibodies or the use of XM techniques lacking extensive evaluation. The authors propose that all XM(+) mandatorily-shared kidneys be examined for IgM autoantibody and that kidneys not be denied to potential recipients due to IgM autoantibody. In addition, to minimize exclusions based on positive B-cell XMs, it is proposed that mandatorily-shared kidneys be shared on the basis of the DR subtypes, insofar as is currently practical.

Hyperacute and acute kidney graft rejection due to antibodies against B cells.

Because of the perception of its uncertain clinical significance, the B cell crossmatch is not universally performed before renal transplantation. Even though sporadic cases of hyperacute rejection associated with B cell antibodies have been reported, doubts remain in light of other studies suggesting no effect on graft survival. This report describes 4 cases of graft rejection (3 hyperacute and 1 acute) that occurred in patients with anti-B-cell antibodies specific against donor HLA-DR or DQ antigens. Absence of anti-donor class I antibodies was confirmed in all cases by 2-color flow cytometry. Strong evidence for an antibody-mediated mechanism was found in one patient with anti-class I and anti-class II antibodies in serum transplanted with a class II mismatched kidney. In this case, only anti-class II antibodies were recovered in the eluate of the nephrectomy specimen. These four cases were compiled from three different institutions over a four-year period, which confirms the infrequent occurrence of these events. While anti-class II antibodies may not always be detrimental for graft survival, these results also confirm that they have the potential to cause hyperacute or acute graft loss. We conclude that the information provided by the B cell crossmatch should be available at the time that a decision to proceed with a renal transplant is made.

Four-year experience with exclusive use of cytomegalovirus antibody (CMV-Ab)-negative donors for CMV-Ab-negative kidney recipients.

Because of unacceptable CMV related morbidity, mortality, and graft loss, we adopted a policy that (-) patients would receive renal allografts only from (-) donors. This policy has resulted in a significant decrease in (1) morbidity (10.6% v 1.7%, P less than .0001), (2) mortality (3.7%) v 0%, P = .002), and (3) graft loss (2.5% v 0%, P = .016). CMV-Ab-negative patients (1) constitute 26% of all patients tested (compared with 36% of all donors tested), (2) receive transplants at the same rate as (+) patients, (3) do not have a prolonged waiting time, and (4) received greater HLA-A, B, -DR mismatched kidneys (3.6 v 3.1, P less than .01).

Organ sharing for good HLA-A,B, and DR matching improves cadaver renal graft survival in SEOPF: retrospective and prospective studies considering delayed graft function, race, center effects, cyclosporine, and other factors.

1. HLA matching is associated significantly with factors including CsA use, ALS use, recipient race, prior graft loss, presensitization, preservation time and most strongly, with organ sharing. However, HLA match is not directly associated with delayed graft function. 2. By univariate and multivariate analyses, good HLA matching provides significant benefits in graft survival regardless of CsA use, organ source or other potentially confounding factors. 3. HLA-A,B, and DR matching have independent and essentially equivalent benefits on graft survival in CsA-treated patients, whereas HLA-A,B matching has a greater benefit in non-CsA-treated patients. 4. Organ sharing, per se, provides no direct detrimental effect on graft survival by univariate or multivariate analysis. 5. By multivariate and univariate analyses, shared/well-matched kidneys provide significantly better graft survival than local/poorly matched kidneys. 6. Delayed graft function is associated in a complex relationship with organ sharing, prior graft failure, presensitization, and CsA use. 7. The increased rate of delayed graft function associated with organ sharing is overcome by the benefit of good HLA matching. 8. Since April 1986, purposeful organ sharing at SEOPF centers for good HLA matching has been associated with improved graft survival, especially in patients at high risk due to presensitization or prior graft failure.

Lymphocytotoxicity crossmatch proficiency testing among regional transplant centers.

During an eight and a half-year period (1976-1984), 408 combinations of different cells and sera involving 12,652 lymphocytotoxicity crossmatch reactions performed by 21-37 histocompatibility laboratories were studied in 20 proficiency tests conducted by the South-Eastern Organ Procurement Foundation. Consensus by 75% or more laboratories were obtained on 336 (82.4%) of these test samples: of the 10,410 reactions examined with the use of these consensus cells and sera, only 649 (6.2%) were discordant. Considering positive and negative reactions separately, the discordant (false) positive and negative rates were similar (6.1%, 6.4%, respectively). Varying specific factors in given tests indicated that discordant results were significantly reduced by (1) dispensing sera in trays centrally rather than locally; (2) using a standard one-wash procedure rather than local or three-wash methods; and (3) using reagent (monospecific) rather than patient (polyspecific) sera. Use of standard versus local rabbit complement did not significantly influence the concordance of results.

Antibodies to crossreactive HLA antigens. Evaluation by cytotoxicity, flow cytometry, and inhibition of monoclonal antibody binding.

Broadly sensitized patients have antibodies that react with cells from most individuals except those having HLA antigens similar to their own. In this work we addressed the question of whether crossreactive antigens could also be considered compatible. Broadly reactive sera were tested in multiple experiments against lymphocytes selectively mismatched for only one HLA-A, B antigen. Antibodies, measured by cytotoxicity and flow cytometry, were detected in most cases, and their prevalence was the same, regardless of whether the mismatched HLA antigen was crossreactive with the patient's. There were several patients bearing one of the A2, B5, or B7 crossreactive group antigens with antibodies against another antigen of the group. Anti-HLA-A2 reactivity was further evaluated by testing the inhibitory effect of broadly reactive sera on the binding of an anti-HLA-A2 monoclonal antibody. Anti-A2 reactivity measured in this assay was detected in A28-positive patients as frequently as in A28-negative patients. These results suggest that antigens of several crossreactive antigen groups are significantly immunogenic and elicit antibodies as often as noncrossreactive antigens. Further studies are necessary to evaluate other less-frequent antigen combinations.

Multivariate analysis of risk factors in cadaver donor kidney transplantation.

Data collected prospectively on 3811 kidney transplants performed between June 1977 and July 1982 with follow-up to July 1984 by the 42 member institutions of the South-Eastern Organ Procurement foundation were analyzed to identify factors associated with graft and patient outcome in patients not receiving cyclosporine. Multivariate Cox regression analysis was used to examine the association and relative risk of 24 variables with three actuarial outcomes: overall graft failure, irreversible rejection, and patient death. Factors having no suggested association with any outcome included: recipient sex, history of pregnancy, blood group, and time on dialysis; organ preservation method, time and source; donor race; crossmatch test sensitivity; and annual center transplant rate. In decreasing order of relative risk, the factors most significantly associated with irreversible rejection were: loss of two or more prior grafts, low HLA-A,B match, lack of pretransplant blood transfusion, high (greater than 60%) pretransplant sensitization to leukocyte (HLA) antigens, and delayed graft function. Splenectomy, insulin-dependent diabetes, and antilymphocyte serum therapy provided the greatest risk of patient death. Factors such as recipient age, race, and native nephrectomy had suggested associations with outcome. By adding each center as a separate covariate in the analysis, other center-dependent factors were quantitated and found in some cases to have a highly significant association with graft and patient outcome. These results provide a basis for evaluating the potential risk of graft loss or patient death for those prospective cadaver kidney transplant recipients not being considered for cyclosporine therapy.

HLA matching for cadaver renal transplantation in SEOPF: the impact of cyclosporine. Southeastern Organ Procurement Foundation.

Since the introduction of CsA in 1983, several changes in SEOPF activity have been observed: 1. Organ recovery has increased at a rate slower than candidate registration, whereas the utilization rate has increased substantially. 2. Overall organ sharing has decreased for both CsA and non-CsA-treated patients. 3. The percentage of poor HLA-A,B matched recipients has increased for both CsA- and non-CsA-treated patients. 4. The use of cold storage preservation has increased for both CsA- and non-CsA-treated patients. 5. The use of ALS has decreased, predominantly in CsA-treated patients. 6. A majority of diabetics are being treated with CsA. 7. There is substantial individual variation in SEOPF center preferences for CsA use, HLA matching, and use of shared kidneys. In terms of graft outcome, the following associations have been observed: 1. The incidence of delayed graft function has increased with shared kidneys only, suggesting sharing of poorer quality as well as fewer kidneys. 2. First transplant recipients receiving CsA tend to have lower delayed graft function rates, possibly as a result of treatment selection. However, the risk of graft failure associated with delayed function is greater in patients receiving CsA. 3. By univariate analysis, there is an additive benefit of HLA-A,B matching and CsA use in patients receiving local kidneys with immediate function. 4. By multivariate analysis, there is a significant relative risk of graft rejection associated with poor HLA-A,B matching in patients receiving CsA. 5. By multivariate analysis, there is an apparent risk of graft loss associated with shared organs, but only in patients receiving CsA. One possible explanation is that poorer quality kidneys are being accepted for patients treated with CsA. 6. By multivariate subset analysis, there is a significant benefit of CsA use in patients whose HLA is poorly matched, but no observed benefit in well-matched patients. 7. Definitive evaluation of the relative effects of CsA and HLA matching on cadaver renal allograft survival must await long-term follow-up data on survival and function, and the ability to control for center bias in sharing, HLA matching, and CsA use.

Use of SEOPF regional crossmatch trays to share kidneys for sensitized patients. Local experience of three centers.

Regional organ procurement (ROP) crossmatch trays are used by members of the South-Eastern Organ Procurement Foundation (SEOPF) to facilitate sharing of cadaver kidneys for highly sensitized patients. ROP trays carry a single representative serum sample from over 900 patients with panel reactive antibody (PRA) levels of greater than or equal to 60%. Trays are centrally prepared periodically and distributed to member laboratories where they are used for preliminary crossmatching against locally obtained donors. Crossmatching results are used in conjunction with the SEOPF computer match program for sharing of kidneys. Proficiency testing studies by the 40-member laboratories show a greater than 90% concordance rate on results with these highly and broadly reactive sera. Data were available from 3 centers on 74 kidneys shared between SEOPF-member institutions on the basis of a remote, preliminary, negative ROP tray crossmatch. Of these, 44 (59%) crossmatched negative locally with the same and other sera, and were thus considered acceptable to be transplanted to the intended highly sensitized patients. Sixteen (22%) donors had a positive crossmatch locally, but with sera other than that present on the ROP tray used for screening. In 14 cases (19%) the same serum as on the ROP tray gave a positive crossmatch. The majority of ROP tray inconsistencies appeared to be due to use of more sensitive crossmatching techniques at the recipient center. Of the 27 patients transplanted at these 3 centers with kidneys received on the basis of ROP tray results, none experienced hyperacute or early irreversible rejection and actual graft survival at 6-48 months is 74%. These studies indicate that regional sharing of patient sera by the existing network of histocompatibility testing laboratories is an effective and reliable mechanism to identify crossmatch-negative donors for highly sensitized patients.

Lack of influence of donor-recipient differences in subtypic HLA-A,B antigens (splits) on the outcome of cadaver renal transplantation.

Data collected prospectively on 3811 cadaver renal transplants performed between June 1977 and July 1982 by the 42 member institutions of the South-Eastern Organ Procurement Foundation (SEOPF) were analyzed to determine whether donor-recipient differences in sub-typic HLA-A,B specialties (splits) influenced outcome. The number of HLA-A,B antigens matched and mismatched between each donor and recipient was calculated in three ways: (1) considering all antigens and splits as distinct (not matched); (2) considering all splits as only matched with their corresponding typic antigen (but not with each other); and (3) considering all splits as matched with both their corresponding typic antigen as well as each other. Overall graft survival, graft loss from irreversible rejection, and patient survival stratified by the level of HLA match were the same using all three methods. In addition, using multivariate Cox regression analysis, the strong association between good HLA matching and increased graft survival was the same using all three methods of matching. Patients with a given number of mismatched antigens had no significant decrease in survival when additional splits were considered mismatched with each other or their corresponding typic antigen. These results suggest that matching of typic HLA-A,B antigens plays a highly significant role in reducing graft rejection but that donor-recipient differences in splits have a negligible effect on graft outcome.

Reasons why kidneys removed for transplantation are not transplanted in the United States.

The Organ Center establishes by the South-Eastern Organ Procurement Foundation collected information on 575 kidneys procured but not transplanted in the United States. The greatest proportion, 393, were not transplanted because a crossmatch-negative recipient was not found. Of these kidneys, 260 were transported to at least one additional center and 115 were offered to an additional center within 24 hr of removal. In 18 instances, attempts to share kidneys were made too late. The blood group representation of these kidneys was 62% A, 15% B, 12% AB, 11% O. The SEOPF system of crossmatches enabling the donor center to perform crossmatches on immunized recipients from 42 other transplant centers still resulted in the loss of 98 kidneys. However, this loss was half that predicted from the national experience. Rather than discarding them, 272 kidneys were transported overseas where 183 were transplanted. Technical problems related to the deceased, organ size, anatomic abnormalities, expended or nonviable material for tissue typing, and perfusion failure led to discarding 182 kidneys. Only 15 kidneys were reported injured irremediably at the time of removal, while 12 had bacterial contamination. The data emphasize our national problem and demand collaboration and new systems for kidney distribution in recipients of non-O blood groups.

The effect of HLA-A, -B matching on cadaver renal allograft rejection comparing public and private specificities.

Data collected prospectively on 3811 cadaver renal transplants performed between June 1977 and July 1982 by the 42 member institutions of the South-Eastern Organ Procurement Foundation (SEOPF) were analyzed to determine whether donor-recipient compatibility based on public rather than private HLA-A,-B specificities influenced the beneficial effect of HLA matching on outcome. HLA compatibility was calculated considering match and mismatch based on common private or various public (crossreactive group, [CREG]) specificities. Donor-recipient compatibility using certain CREG assignments provided an equivalent means of stratifying graft outcome by the degree of HLA-A,-B match or mismatch, and other CREGs assignments did not. Multivariate Cox regression analysis of donor-recipient compatibility based on certain public antigens showed as high an association (P less than 10(-5) between good matching and decreased graft rejection as did matching for private antigens alone. Patient stratification by HLA match provided a stronger association with graft outcome than by HLA mismatch, irrespective of whether private or public antigens were considered. The likelihood of finding a better match was significantly increased using CREG assignments, and patients with at least one matched private antigen had equivalent or better graft survival when additional public antigens were matched. These findings indicate that with conventional immunosuppressive therapy: (1) matching of private or public HLA-A,-B antigens plays a highly significant role in decreasing renal allograft rejection; (2) matching based on certain public antigens can provide the same or a better association with outcome as private antigens; and (3) the association (crossreactivity) of various HLA specificities can be defined on a functional basis in terms of graft survival.

Benefits of HLA-A and HLA-B matching on graft and patient outcome after cadaveric-donor renal transplantation.

Data collected prospectively on 3811 renal transplantations performed between June 1977 and July 1982 by the 42 member institutions of the South-Eastern Organ Procurement Foundation were analyzed to determine the influence of donor-recipient HLA-A and HLA-B matching on patient and graft outcome. Well-matched recipients were more likely to have received kidneys from outside their own centers, were more highly presensitized, included fewer blacks, and were more likely to have lost an earlier graft. Multivariate Cox regression analysis that included these and six other potential confounding variables revealed a significant association (P less than 0.001) between good HLA-A and B matching and increased graft survival. The difference in mean (+/- S.E.) actuarial graft survival between recipients worst matched and best matched for HLA-A and B antigens increased with time: 55 +/- 2 per cent as compared with 64 +/- 4 per cent at six months and 18 +/- 4 per cent as compared with 44 +/- 7 per cent at four years. Poor HLA matching of donor with recipient provided the greatest relative risk (2.16) of irreversible graft rejection of all the variables examined. Among patients with functioning grafts, well-matched recipients had lower serum creatinine levels and received significantly smaller amounts of glucocorticoids. Our findings indicate that good HLA-A and B matching is highly dependent on a system for sharing organs among institutions, and results in decreased graft rejection, better long-term graft function, and less need for post-transplantation immunosuppression.