Acute graft rejection in the late survivors of renal transplantation. Clinical and histological observations in the second decade

The clinical and histological spectrum of renal allograft rejection occurring in the early posttransplant period is well described, but there is not much information with regard to the nature of graft rejection occurring in the long-term survivors of renal transplantation. In this study, we analyzed the incidence, clinical and histological data, and outcome of graft rejection in 69 patients who survived with a functioning kidney for 10 years or longer. In this second decade, during a mean follow-up of 3 years (0.1-9.7 years), 15 patients (22%) developed 20 late rejections. Two of them received living-donor transplants and 13 received cadaver kidneys. Only 8 of these rejections (40%) were associated with abnormal clinical findings; the other 12 (60%) were asymptomatic and were detected on the basis of an unexplained deterioration in graft function. The diagnosis was made on clinical grounds in 10 cases and the other 10 were confirmed by renal histology: acute cellular rejection 1, acute cellular rejection superimposed on chronic rejection 4, and chronic rejection only 5. Thirteen acute rejections in 8 patients were treated with high-dose steroids. Of these, 6 (46%) responded fully, 4 (31%) responded partially, and 3 (23%) did not respond. Seven patients with chronic rejection were not treated. Of these, 5 have returned to dialysis within a mean period of 8 months and one patient died of hepatic failure. Our data suggest that acute reversible graft rejections can occur even after 10 years following renal transplantation. It is therefore essential to continue the maintenance immunosuppressive therapy and monitor the clinical and renal functional data at regular intervals in long-term survivors of renal transplantation.     

Detection of circulating released platelets after renal transplantation

In recipients of renal transplants, the biochemical defect(s) that underlies increased deposition of platelets in the graft and their shortened survival in the circulation are poorly understood. Forty-six recipients of kidney allografts, with and without rejection signs (13 acute rejections (ARs), 15 chronic rejections (CRs), and 18 functioning transplants (FTs), had lower platelet serotonin (5HT) and higher plasma beta-thromboglobulin than normal controls (NCs). These abnormalities were more pronounced in patients with ARs than with CRs but were also present in patients with FTs. All groups of transplant recipients showed an abnormal metabolism of platelet arachidonate, as expressed by low serum levels of thromboxane B2. In AR, plasma fibrinopeptide A (FPA) was significantly high whereas FPA levels were unchanged in CR and in FT. These findings suggest that in patients with renal transplants, the platelet release reaction has occurred in vivo, resulting in the secretion of granule-bound substances and the circulation of partially empty platelets. Vasoactive, mitogenic, and proaggregatory substances released from platelets might damage the graft and aggravate the rejection process.     

Steroid-free immunosuppression in renal transplantation: a long-term follow-up of 100 consecutive patients

BACKGROUND: Our goal in clinical renal transplantation is to establish a steroid-free immunosuppressive protocol that not only promotes long-term patient and graft survival, but also improves the overall well-being of the patients. METHODS: In a prospective, nonrandomized, clinical study 100 consecutive patients transplanted with first and second grafts were discharged from our center with functioning grafts 1996-1999 and followed for up to 4 1/2 years. Patients received steroid-free immunosuppression with an initial 10-day antithymocyte (ATG) induction and maintenance therapy with cyclosporine (CsA) and mycophenolate mofetil (MMF). No steroids were given. RESULTS: After an observation time of up to 4 1/2 years, 1-, 2-, 3-, and 4-year graft survivals of 97, 96, 90, and 82% were observed, with no correlation to HLA-matching, kidney disease, donor age or type, or number of transplants. Ninety-nine patients (1 died or peritonitis after returning to dialysis) were alive and well. Ninety grafts were functioning well, 9 patients returned to dialysis due to recurrence of hemolytic uremic syndrome, and glomerulonephritis in 2 and chronic rejection in 7 grafts after 7-36 months (3 due to non-compliance after 7-30 months). All 7 children below the age of 15 are alive, with well-functioning grafts, except 1 with recurrence of glomerulonephritis who returned to dialysis after 2 1/2 years. There were 13 acute rejections (13%), 10 early (first 3 months) (10%), and 3 late (6-42 months) (3%). All acute rejection episodes were successfully reversed. No lymphomas were observed. CONCLUSIONS: Our first-line, steroid-free immunosuppressive protocol allows initial graft function, provides a safe level of long-term graft survival and function with a very low rejection rate, gives an acceptable rate of side effects, and possesses the potential for lowering the incidence of chronic rejection over the long-term. Compared with protocols that discontinue steroids after the initial posttransplant period, a steroid-free protocol avoids the increased risk of infection, body disfigurement, and other steroid-induced side-effects in the early posttransplant period. It also avoids the long-term risks of steroid use and the increased risk of rejection when the steriods are withdrawn.     

Conversion of renal transplant recipients from cyclosporin to low-dose tacrolimus for refractory rejection

Abstract Twenty-five patients with refractory rejection following renal transplantation were converted from cyclosporin to tacrolimus in an attempt to salvage the allografts. All patients had received two or three pulses of methylprednisolone, 6 had OKT3, 14 had antithymocyte globulin (ATG) and 2 had both OKT3 and ATG prior to conversion. The median time from transplantation to conversion to tacrolimus was 32 days (range 12–322). Patients underwent a simple switch from cyclosporin- to tacrolimusbased therapy with tacrolimus administered at a median dose of 0.15 mg/kg per day. Doses were adjusted according to clinical response and trough blood levels. Twenty-one of the 25 patients (84 %) with refractory rejection showed evidence of reversal of rejection as indicated by a significant reduction in serum creatinine (Student's paired t -test, P < 0.05) following conversion to tacrolimus. None of these patients had further episodes of rejection. Three patients had ongoing rejection and returned to dialysis, and 1 patient showed deteriorating renal function associated with a cytomegalovirus infection. Of 18 patients currently on tacrolimus, 15 have improved renal function and 3 have shown no further deterioration. We conclude that low-dose tacrolimus appears to be effective in salvaging renal allografts with resistant rejection.     

Histologic and immunophenotypic evaluation of pretreatment renal biopsies in OKT3-treated allograft rejections

The histologic features immunophenotype of intragraft mononuclear populations, and HLA-Dr expression in pretreatment formalin-fixed renal allograft biopsies were correlated with outcome of OKT3 therapy in 35 steroid resistant renal transplant rejections. Therapeutic response (63% overall) was better in pure acute cellular rejections (ACR) (13/15, 87%) than ACR with interstitial fibrosis (4/12, 33%) or with vascular injury (5/8, 62%). Intragraft T lymphocytes were more numerous in vascular rejection (mean 566/mm2) compared with pure ACR (mean 265/mm2, P = .049), and macrophages were greater in pure ACR (203/mm2) compared with ACR with interstitial fibrosis (83/mm2, P = .051). Distribution of T cells, B cells, plasma cells, and macrophages among various histologic categories was otherwise statistically similar. There was no correlation between therapeutic response to OKT3 and intragraft concentrations of individual mononuclear cell subsets. Vascular and/or epithelial HLA-Dr expression was present in 17/25 (68%) cases and was not associated with histologic features or treatment response. Follow-up graft function (median 7 months) correlated significantly with therapeutic response to OKT3 (P = .0004) and histologic presence of interstitial fibrosis (P = .031), but was not related to concentration of individual mononuclear subsets or HLA-Dr expression. We conclude that intragraft concentrations of major mononuclear cell types may relate to histology, but that these do not predict treatment response or graft outcome, and thus poorly reflect intensity or possible heterogeneity of host immunologic rejection mechanisms.     

Beneficial effect of plasmapheresis and intravenous immunoglobulin on renal allograft survival of patients with acute humoral rejection

BACKGROUND: Acute humoral rejection (AHR) has been associated with enhanced graft loss. Our study compared the renal allograft survival of patients with AHR treated with plasmapheresis (PP) and intravenous immunoglobulin (IVIG) with allograft survival in patients with acute cellular rejection (ACR). METHODS: We retrospectively analyzed all kidney transplants performed at our institution between January 1999 and August 2001 (n=286). Recipients were classified into three groups according to biopsy reports: AHR, ACR, or no rejection. The ACR group was further divided into early and late rejection (<90 and >90 days posttransplant, respectively). RESULTS: After a mean follow-up of 569+/-19 days, the incidence of AHR was 5.6% (n=16). Recipient presensitization, delayed graft function, early rejection, and higher creatinine at diagnosis were characteristic of AHR. Most AHR patients (14/16) were treated with PP and IVIG. One patient received only IVIG, whereas another received only PP. All AHR patients were given steroid pulses, but only four received antilymphocyte therapy because of concomitant severe ACR. The ACR group comprised 43 patients (15%). One patient with mild rejection received no therapy, 20 improved with steroids alone, and 22 required additional antilymphocyte therapy. One-year graft survival by Kaplan Meier analysis was 81% and 84% in the AHR and ACR groups, respectively (P=NS). Outcomes remained similar when AHR patients were compared with those with early ACR. CONCLUSIONS: We conclude that AHR, when diagnosed early and treated aggressively with PP and IVIG, carries a short-term prognosis that is similar to ACR.     

Renal allograft biopsies in the era of C4d staining: the need for change in the Banff classification system.

C4d immunostaining in the peritubular capillaries (PTC) is a marker of antibody-mediated rejection (AMR). We evaluated the histopathologic diagnoses of 388 renal transplant biopsies since the implementation of routine C4d immunostaining at our center. Of these, 155 (40%) biopsies had evidence of acute cellular rejection (ACR), out of which 119 (77%) had pure ACR, 31 (20%) had ACR with concomitant features of AMR, and five (3%) had ACR with focal C4d staining. Sixty-four (16%) biopsies exhibited features of AMR [33 (52%) pure AMR, and 31(48%) concomitant AMR and ACR]. One hundred and fifty-five (40%) biopsies had features of interstitial fibrosis and tubular atrophy (IFTA). Of these, 20 (13%) had concomitant AMR [13 (8.5%) had pure AMR and seven (4.5%) had concomitant ACR and AMR]. Creatinine at the time of biopsy was higher in patients with mixed ACR and AMR and the clinical behavior of mixed lesions is more aggressive over time. Despite having a lower serum creatinine at the time of biopsy, patients with IFTA experienced gradual decline in graft function over time. The pathologic findings in renal allograft biopsies are often mixed and mixed lesions appear to have more aggressive clinical behavior. These findings suggest the need for change in the Banff classification system to better capture the complexity of renal allograft pathologies.     

The early posttransplant prognosis of acute renal allograft rejection as determined by detection of cytotoxic antibodies to lymphoid B cell lines

We have studied serial samples of pretransplant and posttransplant sera for cytotoxic antibodies to lymphoid B cell lines (LCL) in 45 renal allograft recipients. A total of 48 rejection reactions occurred in 31 patients. A comparison of each patient's most reactive posttransplant serum showed a significantly higher reactivity in the ten patients with early allograft failure when compared with the 21 patients with reversible rejections and the 14 patients who had no rejections. Rejection reactions were easily differentiated by comparing the change in cytotoxic reactivity to LCL of recipients' sera drawn at the time of a rejection episode with the reactivity of their pretransplant sera. In 32 rejections considered non-antibody-associated cytotoxic reactivity of recipients' sera to LCL either decreased or remained essentially unchanged during the rejection. In 16 rejections considered antibody-associated the recipients' sera drawn during the rejection episode showed an increase in cytotoxic reactivity ranging from 40% to 100%. Response to antirejection therapy and three month graft survival had a significant correlation with changes in LCL antibody reactivity during a rejection. Only two of the 32 rejections considered non-antibody-associated failed to reverse compared with eight of the 16 antibody-associated rejections (P less than .001). Graft survival at three months in patients with non-antibody-associated rejections was 90% compared with 27% in the 11 patients who had antibody-associated rejections (P less than .001) Other parameters possibly related to the severity of a rejection reaction or to early allograft prognosis did not differ appreciably between the two types of rejections. This included the time posttransplant to the first rejection episode, the number of patients with multiple rejections in the first three months, and rejections requiring dialysis therapy. Determination of a change in cytotoxic reactivity to LCL during a rejection reaction enables one to predict the response to antirejection therapy and early allograft prognosis. This may ultimately be useful in selecting different types of antirejection therapy for individual patients.     

Histological analysis of late renal allografts of antidonor antibody positive patients with C4d deposits in peritubular capillaries

Abstract:  The association of humoral immunity with late renal allograft dysfunction has recently been recognized, and many reports have revealed C4d deposits in peritubular capillaries (C4d in PTC), and the presence of serum antidonor HLA antibody in patients suffering from graft dysfunction, long time after transplantation. In this study, morphological changes in renal allograft biopsies more than 1 year after transplantation in 14 patients with C4d in PTC and serum antidonor antibody were investigated for the presence of chronic rejection (CR). In addition to the light microscope study, an electron microscope study was done to evaluate the multilayering of the peritubular capillary basement membrane (MLPTC). Histologically, only seven of 14 patients met the criteria of CR, and 71.4% (5/7) of CR patients had episodes of acute humoral rejection (AHR), coexisting with acute tubulointerstitial rejection. Peritubular capillaritis was observed in all patients, although it differed in severity. Transplant glomerulitis and interstitial inflammation were also observed in many patients: 71.4% (10/14) and 92.9% (13/14) respectively. MLPTC was observed in 12 patients (85.7%), but the severity of the MLPTC did not reflect the severity of peritubular capillaritis or any other histological features. The long-term outcomes of the patients CR, especially those with episodes of AHR, were poor, and two of them lost their graft functions. On the other hand, patients without CR had relatively favourable outcomes. In conclusion, we confirmed the diverse morphological changes of late renal allografts, which cannot be categorized as chronic humoral rejection (CHR), and such patients who do not have typical morphological changes such as CHR, should be followed-up on a long-term basis in order to clarify the significance of C4d on PTC in late renal allografts.     

Feasibility and long-term results of autologous PBSC transplantation in recurrent undifferentiated nasopharyngeal carcinoma

BACKGROUND: Recurrent undifferentiated nasopharyngeal carcinoma (UNPC) is a chemosensitive illness. Here we report long-term results of high-dose chemotherapy (HDC) as late intensification, with autologous peripheral blood stem cell (PBSC) support. METHODS: Six patients (5 men, 1 woman; median age 41years; median ECOG PS = 0) with recurrent UNPC (local, 2; local + nodal, 2; bone metastasis, 2) have been enrolled. All patients had been previously treated with neoadjuvant chemotherapy and radiotherapy; 3 of 4 local relapses had received a re-irradiation. Every patient received three courses of cisplatin + epirubicin and 1 cycle of epirubicin followed by PBSC collection. A median of 7.2 x 10(6)/kg (range, 4.5-18) CD34+ cells were reinfused. HDC was according ICE scheme: ifosfamide, 2.5 g/m(2)/d, + carboplatin, 300 mg/m(2)/d, + VP-16, 300 mg/m(2)/d days 1 through 4. RESULTS: After conventional chemotherapy, we had 1 CR (16%), 3 PR (50%), and 2 NC (34%). After HDC, we had 4 CR (66%),1 PR (17%), and 1 MR (17%). Toxicity was manageable. After a median follow-up of 30 months (range, 14-50), two patients are alive without disease (34%), one is alive with bone disease (16%), and three (50%) died of disease at 16, 18, and 24 months. CONCLUSIONS: HDC has an acceptable toxicity, can convert PR in CR, and seems effective, with long-lasting CRs.     

The incidence and impact of early rejection episodes on graft outcome in recipients of first cadaver kidney transplants.

The objective of this study was to define the incidence and significance of acute rejection occurring in the first year following transplantation. The influence of contemporary induction immunosuppression on rejection, as well as the effect of rejection on graft and patient loss, renal function, and maintenance immunosuppression during the first year in 110 recipients of first cadaver renal transplants were analyzed. All patients received CsA, Aza, and prednisone for 30 days with withdrawal of Aza at 30 days and then prednisone at 105 days; 57 patients were prospectively randomized to receive ALG (Merieux) until serum creatinine was less than 300 mumol/L. Short-term ALG administration did not influence the incidence, severity, nature, or outcome of rejection episodes. Fifty-five (50%) patients had at least 1 rejection in the first 90 days. All patients with delayed graft function and 7/8 (88%) sensitized patients (current PRA greater than 50%) had at least 1 rejection episode; 71% (n = 35) of all rejection episodes occurred in the first 30 days posttransplant. Patients rejection free at 90 days remained rejection free the entire first year. Graft loss was 18% for rejections in the first month, 13% for rejections occurring later (P = NS); 20% (n = 11) of patients had a second rejection and 1% (n = 2) had a third rejection. The risk of graft loss was 9% with a first rejection, 38% with a second rejection, and 50% with a third rejection. Of 12 (22%) rejections that were steroid resistant, 10 (83%) were reversed with OKT3. One-year graft survival for patients without rejection, with steroid-sensitive rejection, and with steroid-resistant rejection was 96%, 88% (P = ns), and 58% (P less than 0.001), respectively; 1 year SCr was 168 +/- 93, 196 +/- 77 (P = ns), and 268 +/- 96 microMol/L (P less than 0.05), respectively. Patients free of rejection and with stable renal function continued to do well on maintenance CsA monotherapy, and they were more likely to be on CsA monotherapy than those with rejection episodes (P less than 0.01).     

The first 100 liver transplants at UCLA.

A clinical program in liver transplantation was begun at UCLA in 1984 after a period of laboratory investigation. The first 100 orthotopic liver transplants (OLT) were performed in 83 patients (43 adults and 40 children) between February 1, 1984 and November 1, 1986. Donors and recipients were matched only for size and ABO blood group compatibility, with OLT performed across blood groups in 28 patients. Standard operative techniques were used, including venous-venous bypass in adults. Arterial reconstruction was performed using an aortic Carrel patch or "branch patch" in 65% of cases and by end-to-end or aortic conduit techniques in the remainder. The hepatic artery thrombosis rate was 5%. Biliary reconstruction was choledochocholedochostomy in 67 OLT and Roux-en-Y choledochojejunostomy in 33 (complication rate of 24% and 24%, respectively). Average lengths and ranges of donor liver ischemia, operating time, and blood replacement were 4 hours (range: 1-10 hours), 7.6 hours (range: 4-15 hours), and 17 units packed cells (range: 2-220 units). Immunosuppressive regimen was cyclosporine-steroid combination, with monoclonal anti-T-cell antibody (OKT3) used for refractory rejection. All patients had one or more complications: pulmonary (78%), infectious (51%), renal dialysis (25%), neurologic (22%). All patients had at least one episode of acute rejection, and 3.6% had chronic rejection. Retransplantation was needed in nine patients once and in four patients twice. The overall retransplant survival rate was 54%, and two of four patients who received a second retransplant are alive. Sixty-three of the 83 patients (76%) are alive (adults 72%, children 80%). The 1- and 2-year actuarial survival rate is 73% (adults 68%, children 78%). Thirty-eight of 43 patients (88%) who had transplantation in the past year are alive. Of 14 perioperative variables assessed as predictors of early mortality, only postoperative dialysis (p less than 0.0005) and presence of severe rejection (p less than 0.01) had statistical significance. Seventy per cent of adults returned to work, and 84% of children had normal or accelerated growth. A new program in liver transplantation provides a dramatic option in patient care and an academic stimulus to the entire medical center.     

Clinical rejection is distinguished from subclinical rejection by increased infiltration by a population of activated macrophages.

It has been reported previously that one-third of protocol renal biopsies in asymptomatic, biochemically stable renal transplant recipients in the first 6 mo show unsuspected subclinical graft rejection (both infiltrate and tubulitis) and that subclinical rejection is a risk factor for chronic renal dysfunction. This study was performed to determine whether differences in phenotype or activation status of graft-infiltrating cells underlie these different manifestations of acute rejection. Biopsies with normal histology (n = 10), subclinical rejection (n = 13), and clinical rejection (n = 9) were studied using immunohistochemistry and computerized image analysis. Subclinical and clinical rejections had similar histologic Banff scores. Univariate analysis showed a trend for a higher infiltration with CD8+ (P = 0.053) and CD68+(P = 0.06) cells in clinical rejection. Of the activation markers studied (CD25, perforin, tumor necrosis factor-alpha), only allograft inflammatory factor-1+-activated macrophages were significantly (P = 0.014) increased in the infiltrate of clinical rejection biopsies. These data suggest that activated macrophages or their products are responsible for acute renal dysfunction associated with clinical rejection episodes.     

Acute renal allograft rejections with major interstitial oedema and plasma cell-rich infiltrates: high gamma-interferon expression and poor clinical outcome.

BACKGROUND: Acute rejections are scored according to three main criteria: vasculitis, tubulitis and interstitial infiltration as defined in the Banff classification. Typically, B cells account for <8% of the infiltrates and oedema is limited. The clinical significance of severe interstitial oedema and plasma cell-rich infiltrates (OPcR) are still a matter of debate. METHODS: Kidney graft biopsies performed between 1991 and 1998 were retrospectively evaluated for these two criteria. RESULTS: Among the 826 biopsies performed during the study period, 14 samples in 12 patients met these criteria; 11 were of Banff type I acute rejection and three were borderline. Based on clinical data, all were treated as acute rejections. OPcR occurred at a median of 187 days post-transplantation. All episodes were steroid resistant. Graft survival was 40% at 1 year following the rejection. Circulating antibodies reactive either to donor HLA or to endothelial cells were present in eight of 12 patients and widespread C4d deposit in peritubular capillary were present in three out of five patients studied. Level of gamma-interferon mRNA within the graft was significantly higher than in standard acute cellular rejection (ACR). CONCLUSION: This study showed that OPcR rejections portend a poor outcome irrespective of the Banff score. Our data strongly support the hypothesis that a humoral component participated in the graft injuries. Altogether, the data suggest that OPcR rejection might represent a late and attenuated variant of acute humoral rejection that should be classified separately from ACR.     

Ruptured human renal allograft. Pathogenesis and management.

From January, 1963, to January, 1977, 4 cases of acute allograft rupture occurred in 474 renal transplants performed at the Cleveland Clinic, an incidence of 0.8 per cent. Rupture developed between the fifth and sixteenth day after transplantation during a period when the patients required dialysis because of poor allograft function. All patients had surgical exploration and successful repair of the laceration. Biopsies in each case at the site of laceration revealed findings consistent with acute allograft rejection. The rejections were mild in 2 cases, moderate in one, and severe in another. Two kidneys failed to sustain function, and the patients were returned to chronic hemodialysis two to five months later. None required a nephrectomy. The other two kidneys are functioning well, with serum creatinine values of 1.3 and 1.5 mg./100 ml. one year after allograft rupture. Since rupture of a renal allograft does not appear to increase the intensity of rejection nor does it represent a severe type of rejection, transplant nephrectomy can be avoided unless hemorrhage is uncontrollable from the site of laceration.     

慢性排斥治疗的经验与体会

为探讨慢性排斥的治疗方法对５９例肾移植术后发生慢性排斥反应患者的治疗情况进行总结。治疗包括调整原免疫抑制方案，加用甲泼尼龙，环磷酰胺，单克隆及多克隆抗体，雷公藤，百令胶囊，尿毒清等，结果１１例的肾功能得以恢复或稳定。     

Pretransplant monitoring of donor-recipient compatibility.

In these studies, pretransplant testing of donor-recipient compatibility was performed in 10 related donor and 26 cadaveric renal transplants using a variety of cell-mediated immunity tests. Mixed lymphocyte culture results did not correlate with acute rejection (AR), acute irreversible rejection, or chronic rejection (CR). Lymphocyte-mediated cytolysis also did not correlate with AR, acute irreversible rejection, or CR. Cell-mediated lympholysis correlated with AR but not with acute irreversible rejection or CR. Antibody-dependent cell-mediated cytolysis (ADCMC) was positive pretransplant in 13 (36%) of the recipients. Of the positive patients, 4 had early severe AR and 9 developed typical CR. Of these 13 patients, 9 or 69% lost graft function to rejection whereas only 3 of 20 (15%) of ADCMC-negative patients lost graft function because of rejection (P less than 0.05). In summary, cell-mediated lympholysis testing demonstrated a capability to predict AR episodes. The most useful pretransplant monitoring assay in this patient series was the ADCMC assay. A positive ADCMC against donor cells pretransplant indicates a relatively poor prognosis for long-term graft survival.     

Effect of increasing baseline immunosuppression on the prevalence of clinical and subclinical rejection: a pilot study.

This group has reported that treatment of subclinical rejection in the first 3 mo posttransplant with corticosteroids decreases late clinical rejections and improves graft function at 2 yr in renal transplant recipients. The current study was performed to determine whether an increase in baseline immunosuppression would decrease the prevalence of early subclinical rejections, as well as the incidence of early and late clinical rejections. Patients received mycophenolate mofetil (MMF) and Neoral cyclosporin A (CsA) posttransplant (n = 29), of which 17 underwent protocol biopsies at months 1, 2, 3, and 6 (Neoral + MMF Protocol Biopsy [Bx]), while 12 declined protocol biopsies (Neoral + MMF Control). These individuals were compared with 72 historical control patients treated with Sandimmune CsA and Imuran, of which 36 had undergone protocol biopsies at months 1, 2, 3, and 6 (Sandimmune + Azathioprine [AZA] Protocol Bx), and 36 had a protocol biopsy at month 6 (Sandimmune + AZA Control). Baseline immunosuppression with Neoral + MMF decreased the incidence of early clinical rejections (0 to 3 mo) and cumulative corticosteroid exposure, but had no impact on the prevalence of early subclinical rejection. Moreover, to maximally decrease the risk of developing late clinical rejections (months 7 to 12) in Neoral + MMF patients required that protocol biopsies be done and that subclinical rejection be treated. The paradoxical finding of recent clinical trials that a reduction in acute clinical rejection has not improved long-term graft outcome may be explained in part by the failure to control subclinical rejection.     

The incidence and significance of late acute cellular rejection (>1000 days) after liver transplantation

Acute cellular rejection (ACR) after liver transplantation occurs in as much as 70% of patients within the first year. There is very little known about ACR that occurs more than 1 yr after transplant, and it is generally believed that late occurring ACR may be more resistant to medical treatment and is associated with a higher rate of chronic ductopenic rejection and graft loss. A total of 532 recipients with more than 1000 d follow-up and who did not have hepatitis C were identified. Forty-three (8.1%) had biopsy proven late ACR at a mean of 1545 +/- 441 d post-transplant. Additionally, 38 of the 43 (88.4%) patients with late ACR had earlier episodes of ACR before 1000 d post-transplant vs. only 295 of the 488 patients (60.5%) that did not have late ACR (p < 0.01). The incidence of primary sclerosing cholangitis (PSC) was 32.6% among patients with late ACR and 11.1% among patients without late ACR (p < 0.01). The overall patient survival for patients who had late ACR (n = 43) is 81.4% while for patients without late ACR (n = 488) it is 82.0% (p = ns). Patients remain at risk for ACR even after 1000 d post-transplant, particularly those with PSC.     

在移植肾功能稳定的受者中主动撤除环孢素A的临床研究

目的 研究在移植肾功能稳定的受者中主动撤除环孢素A(CSA)对急性排斥反应发生率及肾功能的影响.方法 选择35例肾功能稳定的肾移植受者,其中尸体肾移植23例,亲属活体肾移植12例.除2例为再次肾移植外,其余均为初次肾移植.分别在肾移植术后6个月～6年时停用CsA,平均为术后(13.3±9.1)个月.撤除CsA后免疫抑制方案为:霉酚酸酯(MMF)+西罗莫司(SRL)+泼尼松(Pred).撤除CsA前有9例做了移植肾穿刺活检,8例测定了抗HLA抗体.结果 对35例受者随访6个月～4.5年,平均14.8个月.撤除CsA前、后血肌酐平均值分别为(88.1±15.5)μmol/L和(92.3±23.7)/μmol/L(P0.05).撤除CsA后,有2例经活检证实发生急性排斥反应,治疗后均逆转;CsA所致的毒副作用,如牙龈增生、糖耐量异常和多毛症等明显改善.9例移植肾活检中,有3例肾功能正常的受者已出现轻度慢性移植肾肾病表现.抗HLA抗体检测中,7例阴性者在撤除CsA前、后肾功能无明显变化.1例抗HLA抗体呈强阳性者在撤除CsA后进展为慢性移植肾肾病,恢复血液透析.结论 对移植肾功能稳定的受者在移植6个月后撤除CsA,转换为"霉酚酸酯+西罗莫司+泼尼松"的免疫抑制方案是安全的,不增加急性排斥反应风险;撤除CsA有利于消除一些与其相关的毒副作用;对抗HLA抗体呈强阳性者.撤除CsA后很难改变肾功能的进展.