Recipient age and weight affect chronic renal allograft rejection in rats.

Nephron doses and immune responses change with age. Therefore, age is a potential risk factor for graft survival after kidney transplantation. The aim of this study was to determine whether age-related differences are of importance for long-term outcomes after renal transplantation. Kidneys from Fisher 344 rats were orthotopically transplanted into nephrectomized Lewis rats. Kidneys were transplanted using donors and recipients of three age levels, i.e., young (8 wk of age), adult (16 wk of age), and old (40 wk of age). Rats were killed 24 wk after transplantation, and functional, morphologic, and molecular evaluations were performed. Recipient age, rather than donor age, determined graft survival rates. No significant correlation was observed between donor kidney weight on the day of transplantation and morphologic results. Advanced recipient age was associated with reduced creatinine clearance, more severe histologic injuries, including extended glomerular sclerosis, interstitial fibrosis, and vascular lesions, more pronounced cellular infiltration, and greater expression of transforming growth factor-beta and platelet-derived growth factor A and B chains. Although no significant correlation between donor age or kidney weight on the day of transplantation and morphologic results was observed, there was a significant correlation between recipient body weight on the day of transplantation and allograft injury. It is concluded that recipient age and weight affect chronic renal rejection. Renal allografts may benefit from young recipient age but may deteriorate in old recipients, suggesting effects of recipient functional demand on long-term outcomes.     

Predictors and outcomes of delayed graft function after living‐donor kidney transplantation

Delayed graft function (DGF) following deceased donor kidney transplantation is associated with inferior outcomes. Delayed graft function following living‐donor kidney transplantation is less common, but its impact on graft survival unknown. We therefore sought to determine risk factors for DGF following living‐donor kidney transplantation and DGF's effect on living‐donor kidney graft survival. We analyzed living‐donor kidney transplants performed between 2000 and 2014 in the UNOS dataset. A total of 64 024 living‐donor kidney transplant recipients were identified, 3.6% developed DGF. Cold ischemic time, human leukocyte antigen mismatch, donor age, panel reactive antibody, recipient diabetes, donor and recipient body mass index, recipient race and gender, right nephrectomy, open nephrectomy, dialysis status, ABO incompatibility, and previous transplants were independent predictors of DGF in living‐donor kidney transplants. Five‐year graft survival among living‐donor kidney transplant recipients with DGF was significantly lower compared with graft survival in those without DGF (65% and 85%, respectively, P < 0.001). DGF more than doubled the risk of subsequent graft failure (hazard ratio = 2.3, 95% confidence interval: 2.1–2.6; P < 0.001). DGF after living‐donor kidney transplantation is associated with inferior allograft outcomes. Minimizing modifiable risk factors may improve outcomes in living‐donor kidney transplantation.     

The impact of gender and age matching for long-term graft survival in living donor renal transplantation

In renal transplantation, donor age and allograft size are known to have an important influence on the outcome of the graft reflecting functional renal mass. Women tend to have smaller kidneys with 17% fewer nephrons than male kidneys. The number of glomeruli per kidney as well as the mean glomerular volume closely correlate with kidney weight and negatively correlate with subject age. We evaluated the impact of gender and age matching in living-donor renal transplantation on long-term graft survival. MATERIALS AND METHODS: Four groups were discerned among 614 renal transplants, according to donor and recipient gender: Group 1 was male donor to male recipient; Group 2 was male donor to female recipient; Group 3 was female donor to male recipient; and Group 4 was female donor to female recipient. We analyzed long-term graft survival and risk factors between the four groups as well as according to age matching. Statistical significance was determined by the Kaplan-Meier method and log rank test (P < .05). RESULT: The graft survival rates at 1, 3, 5, and 10 years were 92.62%, 88.13%, 82.37%, and 76.07%, respectively. The risk factors affecting long-term graft survival were donor age, donor gender, acute rejection rate, and HLA-DR matching. Among the four groups, the graft survival rates of Group 3 (female donor to male recipient) were significantly different from the other groups (P = .0165). Also, the long-term graft survival rates according to age differences were significantly different between older donors than recipients and younger donors than recipients in each group (P = .0213). CONCLUSION: The importance of inadequate renal mass is magnified in high-risk recipients. Age matching could perhaps improve the results of transplantation, particularly when kidneys from older donors are used. Consideration of age and gender as criteria for the choice of donors and recipients may be considered in organ allocation.     

Subclinical Inflammation and Chronic Renal Allograft Injury in a Randomized Trial on Steroid Avoidance in Pediatric Kidney Transplantation

Steroid avoidance is safe and effective in children receiving kidney transplants in terms of graft function and survival, but the effects on allograft histology are unknown. In this multicenter trial, 130 pediatric renal transplant recipients were randomized to steroid‐free (SF; n = 60) or steroid‐based (SB; n = 70) immunosuppression, and underwent renal allograft biopsies at the time of graft dysfunction and per protocol at implantation and 6, 12 and 24 months after transplantation. Clinical follow‐up was 3 years posttransplant. Subclinical acute rejection was present in 10.6% SF versus 11.3% SB biopsies at 6 months (p = 0.91), 0% SF versus 4.3% SB biopsies at 1 year (p = 0.21) and 0% versus 4.8% at 2 years (p = 0.20). Clinical acute rejection was present in 13.3% SF and 11.4% SB patients by 1 year (p = 0.74) and in 16.7% SF and 17.1% SB patients by 3 years (p = 0.94) after transplantation. The cumulative incidence of antibody‐mediated rejection was 6.7% in SF and 2.9% in SB by 3 years after transplantation (p = 0.30). There was a significant increase in chronic histological damage over time (p < 0.001), without difference between SF and SB patients. Smaller recipient size and higher donor age were the main risk factors for chronic histological injury in posttransplant biopsies.     

Renal allograft rupture caused by acute tubular necrosis

Renal allograft rupture is a rare but potentially lethal complication of kidney transplantation. A renal allograft recipient receiving quadruple immunosuppressive therapy developed a spontaneous allograft rupture 13 days after kidney transplantation. Warm ischaemia time during the transplant was 80 minutes. The ruptured kidney graft could not be salvaged because of the patient's haemodynamic instability. The histopathological examination showed interstitial oedema with severe acute tubular necrosis with no signs of acute rejection. The most common causes of renal graft rupture are acute rejection and vein thrombosis, while acute tubular necrosis may only rarely be responsible for this complication. Renal graft rupture may be the result of interstitial damage attributed both to the prolonged warm ischaemia time during the transplant and to post-transplant acute tubular necrosis in the absence of graft rejection. In those patients whose haemodynamic status cannot be stabilized by appropriate aggressive haemodynamic support therapy, graft nephrectomy should be considered the only definitive treatment.     

儿童小体积供肝肝移植治疗成人急性肝衰竭1例附文献复习

目的  总结儿童小体积供肝肝移植治疗成人急性肝衰竭的临床经验。方法  回顾性分析1例低龄儿童小体积供肝肝移植治疗成人急性肝衰竭病例的临床资料并进行文献复习。结果  供体为4.5岁儿童,脑死亡器官捐献供肝质量为544.6 g,受体体质量52 kg,移植物受体体质量比为1.05%。手术采用经典原位肝移植术。术后艰难康复,相继并发脑水肿、应激性消化道大出血、急性肾损伤、小肝综合征、肺不张、肺部感染、真菌感染、腹腔感染、胸腔积液等并发症。经对症综合治疗后,移植肝功能逐渐恢复正常,2~3周再生至移植成人标准肝体积大小,住院102 d后康复出院。术后10个月随访受体肝功能正常,生活质量良好。结论  儿童小体积供肝可以成功应用于成人受体,但需要根据供肝情况选择合适的受体、手术方式及围手术期精细管理。     

Inadequate donor size in cadaver kidney transplantation

There have been conflicting reports that kidneys from small donors may be at increased risk for late graft failure if they are transplanted into large recipients. Data from the United States Renal Data System was used to study all first cadaver kidney transplantations performed during the years 1994 to 1999. Donor and recipient body surface area (BSA) combinations were included along with other patient and transplant characteristics in a Poisson analysis of factors associated with early (in the first 4 mo) and late (> or =4 mo) graft failure. The numbers of large (BSA >2.2 m(2)) and medium size (BSA 1.6 to 2.2 m(2)) recipients that received kidneys from small (BSA <1.6 m(2)) donors are less than expected (chi(2) = 118.09; P < 0.0001), suggesting that transplant centers may be refusing some kidneys on the basis of donor-recipient size differences. Large recipients who received kidneys from small donors made up 1.5% of the population and had a 43% (95% CI, 17 to 75%; P = 0.0004) increased risk of late graft failure compared with medium-size recipients who received kidneys from medium-size donors (53.4% of the population). Medium-size recipients who received kidneys from small donors made up 12.0% of the population and had a 16% (95% CI, 6 to 26%; P = 0.0012) increased risk of late graft failure. Disparities in recipient and donor size had similar adverse affects on mortality. Effects of recipient obesity (body mass index) and donor gender on late graft survival were no longer statistically significant after the effects of donor and recipient body size were taken into account. In conclusion, the relative size of the donor and recipient should possibly be taken into account when choosing kidneys for transplantation.     

Randomized trial of tacrolimus plus mycophenolate mofetil or azathioprine versus cyclosporine oral solution (modified) plus mycophenolate mofetil after cadaveric kidney transplantation: results at 2 years

BACKGROUND: A previous report described the 1-year results of a prospective, randomized trial designed to investigate the optimal combination of immunosuppressants in kidney transplantation. Recipients of first cadaveric kidney allografts were treated with tacrolimus+mycophenolate mofetil (MMF), cyclosporine oral solution (modified) (CsA)+MMF, or tacrolimus+azathioprine (AZA). Results at 1 year revealed that optimal efficacy and safety were achieved with a regimen containing tacrolimus+MMF. The present report describes results at 2 years. METHODS: Two hundred twenty-three recipients of first cadaveric kidney allografts were randomized to receive tacrolimus+MMF, CsA+MMF, or tacrolimus+AZA. All regimens contained corticosteroids, and antibody induction was used only in patients who experienced delayed graft function. Patients were followed up for 2 years. RESULTS: The results at 2 years corroborate and extend the findings of the previous report. Patients randomized to either treatment arm containing tacrolimus experienced improved kidney function. New-onset insulin dependence remained in four, three, and four patients in the tacrolimus+MMF, CsA+MMF, and tacrolimus+AZA treatment arms, respectively. Furthermore, patients with delayed graft function/acute tubular necrosis who were treated with tacrolimus+MMF experienced a 23% increase in allograft survival compared with patients receiving CsA+MMF (P=0.06). Patients randomized to tacrolimus+MMF received significantly lower doses of MMF compared with those administered CsA+MMF. CONCLUSIONS: All three immunosuppressive regi-mens provided excellent safety and efficacy. How-ever, the best results overall were achieved with tacrolimus+MMF. The combination may provide particular benefit to kidney allograft recipients who develop delayed graft function/acute tubular necrosis. Renal function at 2 years was better in the tacrolimus treatment groups compared with the CsA group.     

Delayed graft function and cast nephropathy associated with tacrolimus plus rapamycin use

Delayed graft function (DGF) occurs in 15 to 25% (range, 10 to 62%) of cadaveric kidney transplant recipients and up to 9% of living donor recipients. In addition to donor, recipient, and procedural factors, the choice of immunosuppression may influence the development of DGF. The impact of immunosuppression on DGF was studied. The frequency of DGF was evaluated in first cadaveric or living donor kidney allograft recipients (n = 144) transplanted at the University of Washington from November 1999 through September 1, 2001. Donor, recipient, and procedural factors, as well as biopsy results, were compared between patients who developed DGF and those who did not. DGF was more common in patients treated with rapamycin than without (25% versus 8.9%, P = 0.02) and positively correlated with rapamycin dose (P = 0.008). In those developing DGF, the duration of posttransplant dialysis increased with donor age (P = 0.003) but decreased with mycophenolate mofetil use (P = 0.01). All biopsies during episodes of DGF demonstrated changes of acute tubular injury. Of the patients with tubular injury, 12 treated with rapamycin and tacrolimus developed intratubular cast formation indistinguishable from myeloma cast nephropathy. Histologic, immunohistochemical, and ultrastructural studies indicated that these casts were composed at least in part of degenerating renal tubular epithelial cells. These findings suggest that rapamycin therapy exerts increased toxicity on tubular epithelial cells and/or retards healing, leading to an increased incidence of DGF. Additionally, rapamycin treatment combined with a calcineurin inhibitor may lead to extensive tubular cell injury and death and a unique form of cast nephropathy.     

Assessment of factors determining graft size in transplant of cadaver kidneys from child donors

BACKGROUND: Kidneys from child donors are very efficient at adapting to the recipient organism. This research aims to verify the size of kidney grafts from pediatric donors after transplant and to identify factors responsible for the size attained by these kidneys. Moreover, it aims to seek relationships between size and function of the transplanted pediatric kidney. METHODS: Seventy-seven renal transplants performed at least 6 months earlier, with cadaver donor 15 years old or younger, had ultrasound measurements of the graft and renal function assessment. Potential factors for graft volume were analyzed using bivariate analysis, followed by multiple linear regression. RESULTS: After a follow up of 4.2+/-3.3 years posttransplant, the grafts presented the following range of measures: length 10.61+/-1.13 cm, width 4.67+/-0.84 cm, and depth 4.76+/-0.99 cm. Graft volumes were 126.62+/-47.76 cm. Bivariate analysis showed that (1) age of both donor and recipient at transplantation; (2) sex of recipient; (3) occurrence of acute rejection episodes were statistically significant. After multivariate analysis, age and sex of recipients were the only significant factors influencing graft volume; child kidneys reached greater volumes when transplanted into adult and male individuals. Larger volume kidneys presented significantly more proteinuria. No difference was evident with regard to creatinine clearance values or urinary retinol binding protein among kidneys of differing sizes. CONCLUSIONS: The size of the recipient (age and sex) is the main factor responsible for volumes achieved by kidneys from pediatric donors. The volume attained by these kidneys demonstrated no relationship with glomerular or tubular function of the organ.     

Chronic allograft nephropathy: current concepts and future directions

The paradigm that chronic rejection causes all progressive late allograft failure has been replaced by a hypothesis of cumulative damage, where a series of time-dependent immune and nonimmune mechanisms injure the kidney and lead to chronic interstitial fibrosis and tubular atrophy, representing a final common pathway of injury and its consequent fibrotic healing response. Allograft damage is common, progressive, time-dependent, clinically important and modified by immunosuppression. Early after transplantation, tubulointerstitial damage is predominantly related to ischemia reperfusion injury, acute tubular necrosis, acute and subclinical rejection and/or calcineurin inhibitor nephrotoxicity, superimposed on preexisting donor disease. Later, cellular inflammation lessens and is replaced by microvascular and glomerular injury from calcineurin inhibitor nephrotoxicity, hypertension, immune-mediated fibrointimal vascular hyperplasia, transplant glomerulopathy and capillary injury, polyoma virus and/or recurrent glomerulonephritis. Additional mechanisms of injury include internal architectural disruption of the kidney, cortical ischemia, persistent chronic inflammation, replicative senescence, cytokine excess and fibrosis induced by epithelial-to-mesenchymal transition. Current understanding of the etiology, pathophysiology and evolution of pathological changes are detailed. An approach to histological assessment of the individual failing graft are presented and a series of postulates are defined for future studies of chronic allograft nephropathy.     

The effect of donor gender on graft survival

Differences in actuarial graft survival according to donor gender have been reported for renal allografts and for cardiac and hepatic allografts, but for the latter in small series with limited biostatistical power. Using the large database of the Collaborative Transplant Study (CTS), this study is an evaluation of graft survival according to donor and recipient gender for renal (n = 124,911), cardiac (n = 25,432), and hepatic (n = 16,410) transplants. Confounders, such as calendar year, geographical area, race, donor and recipient age, HLA mismatch, cold ischemia time, and others, as well as interaction terms were taken into consideration. Death-censored actuarial renal allograft survival from female compared with male donors was less in female recipients and even more so in male recipients. The donor gender-associated risk ratio for graft loss was 1.15 in female recipients and 1.22 in male recipients. The age-gender interaction term was statistically significant, the gender effect being more pronounced for younger (16 to 45 yr) compared with older (>45 yr) donors. Serum creatinine concentrations 1 yr after transplantation were also higher for recipients with kidney grafts coming from female donors irrespective of recipient gender. For first cardiac transplants, graft survival was inferior when the donor was female and the recipient male, but no statistical difference according to donor gender was demonstrable in female recipients. For first hepatic transplants overall, no significant differences according to donor gender were noted. The proportion of recipients who had treatment for rejection crisis during the first year was higher for male recipients of kidneys from female donors compared with male donors. No difference according to donor gender was demonstrable in female recipients. For cardiac and hepatic grafts, no significant effect of donor gender on the proportion of patients treated for rejection episodes was noted. The data show that adverse effects of female donor gender for different organs is much less uniform than reported in the past. An important confounder is donor age. A gender effect on graft survival is also observed for cardiac allografts. Therefore, in addition to potential "nephron underdosing," further pathomechanisms must play a role, possibly differences in immunogenicity according to donor gender.     

Clinical factors associated with graft fibrosis in kidney-transplant recipients on steroid-avoidance immunosuppression

Abstract: Background: Recent studies have documented good patient and graft outcomes and a low risk of acute rejection with steroid‐avoidance immunosuppression in kidney‐transplant recipients, but the risk of progressive graft fibrosis is not well studied. Methods: All adult primary kidney transplant or combined kidney and pancreas transplant recipients on steroid avoidance immunosuppression were eligible for study. All recipients received induction with antithymocyte globulin or basiliximab. Corticosteroids were stopped after day 4 post‐transplantation. Patients were maintained with tacrolimus and mycophenolate mofetil. Protocol biopsies were done at reperfusion and at one, four, and 12 months after transplantation. Results: Eighty one‐yr protocol biopsies with adequate specimens were obtained from 132 kidney or kidney–pancreas transplant recipients. Fifteen (19%) of the biopsies showed moderate to severe graft interstitial fibrosis (GIF) (Banff ci score ≥2). Recipients with GIF were older, had lower body mass index, greater human lymphocyte antigen (HLA) mismatch, older donors, serum creatinine ≥1.6 mg/dL at one month, a Banff ci score >0 on one‐month biopsy, BK nephropathy, and interstitial cellular infiltrates on the one‐yr biopsy. In the unadjusted logistic regression analysis, BK nephropathy, serum creatinine ≥1.6 mg/dL at one month, recipient age, Banff ci score >0 on one‐month biopsy, and donor age were the only variables associated with a higher risk of GIF on the one‐year biopsy. In the multivariate logistic regression model adjusted for these variables, BK nephropathy, serum creatinine ≥1.6 mg/dL at one month after transplantation, and recipient age were independently associated with the risk of GIF on the one‐year biopsy. Conclusion: In this small study of primary kidney or combined kidney–pancreas transplant recipients on steroid‐avoidance immunosuppression, we found that 19% had GIF on a one‐year protocol biopsy. BK nephropathy, serum creatinine ≥1.6 mg/dL one month after transplantation, and recipient age correlated with an increased risk for GIF on the one‐yr biopsy.     

Longitudinal analysis of chronic allograft nephropathy: clinicopathologic correlations

BACKGROUND: Loss of the allograft from chronic allograft nephropathy and death of the patient from vascular, malignant, or infective disease are the major problems in renal transplantation today. Protocol biopsy of the long-term kidney has provided new data with which to develop strategies for prevention and treatment of chronic allograft nephropathy. METHODS: Two series of long-term protocol biopsies are reviewed. In the first, renal biopsies were obtained at time 0, and at 3 months and 12 months, and the recipients of the renal allografts were followed up for up to 15 years. In the second, the kidneys of recipients of simultaneous pancreas kidney transplants were biopsied annually for 10 years, and the results correlated with clinical events. RESULTS: Chronic allograft nephropathy is caused by acute and chronic immune-mediated damage, as well as by chronic calcineurin inhibitor nephrotoxicity. Both immune and nonimmune mechanisms exacerbate pre-existing donor disease and ischemia-reperfusion injury. Established interstitial fibrosis and arteriolar hyalinosis lead to progressive glomerular sclerosis and eventual loss of the graft. CONCLUSION: Protocol biopsies have shown that clinical parameters of renal function underestimate the severity of chronic graft damage. Strategies for preventing or treating chronic renal allograft dysfunction and subsequent graft loss must better control rejection and simultaneously avoid nephrotoxicity.     

Does cadaveric donor renal transplantation ever provide better outcomes than live-donor renal transplantation?

BACKGROUND: Live donor renal transplantation (LRT) now comprises more than 40% of all kidney transplants performed in the United States. Many patients on the cadaveric waiting list have a prospective live kidney donor. This study determines whether cadaveric donor renal transplantation (CRT) can demonstrate better outcomes than LRT. METHODS: From the United States Renal Data System registry, 31,909 adult recipients of a first-time kidney transplant from 1995 to 1998 were analyzed. Recipients were followed until December 31, 2000. RESULTS: CRT, more human leukocyte antigen (HLA) mismatches, increased donor age, cold ischemia time greater than 24 hr, African American recipient, and a history of diabetic nephropathy all increased the risk of graft failure, return to dialysis, and death. Nevertheless, in specific circumstances, CRT could provide better outcomes than LRT. For example, in recipients aged 18 to 59 years with a hypothetical live kidney donor aged 50 years and four HLA mismatches, the relative risk of graft loss with LRT is comparable or increased compared with CRT if the cadaveric kidney donor is much younger or with fewer HLA mismatches. On the other hand, for recipients aged 60 years or older, CRT never provides better outcomes than LRT. All analyses were adjusted for recipient race, gender, and history of diabetic nephropathy. There were no significant interactions among donor type, HLA mismatches, donor age, and cold ischemia time. CONCLUSIONS: The elderly recipient with an imminent LRT should never be offered CRT. A combination of recipient and donor factors can make CRT preferable to LRT in younger patients.     

Decreased renal function is a strong risk factor for cardiovascular death after renal transplantation

BACKGROUND: Chronic kidney disease is thought to be a potential risk factor for cardiovascular death. In renal-allograft recipients, cardiovascular disease is the most significant cause of death. The purpose of this study was to investigate if renal function has a significant role in determining the risk for cardiovascular death in renal-allograft recipients. METHODS: We analyzed 58,900 adult patients registered in the United States Renal Data System who received a primary renal transplant between 1988 and 1998 and who had at least 1 year of graft survival. The primary study endpoint was death from a cardiovascular event beyond 1 year of transplantation. Secondary endpoints were death caused by infections and malignancy-related deaths. Cox proportional-hazard models were used to estimate the effect of renal function on cardiovascular death, infectious death, and malignancy-related death while correcting for potential confounding variables, such as donor and recipient age, gender, race, cause of end-stage renal disease, length of dialysis before transplantation, year of transplantation, donor source and age, delayed graft function, and immunosuppressive regimen. RESULTS: Serum creatinine values at 1 year after transplantation were strongly associated with the risk for cardiovascular death. Above a serum creatinine value of 1.5 mg/dL, there was a significant and progressive increase in the risk for cardiovascular death. The risk of cardiovascular death was significantly higher when patients who lost allograft function were included in the analysis. There was an association between worsening renal function and infectious death, but there was no association between renal function and malignancy-related death. CONCLUSION: Serum creatinine at 1 year is strongly associated with the incidence of cardiovascular death independent of known risk factors.     

Tacrolimus in induction immunosuppressive treatment in renal transplantation: comparison with cyclosporine

The aim of the study was to compare the efficacy and safety of induction immunosuppression therapies based on tacrolimus or cyclosporine (CsA) in kidney transplantation. The 240 kidney allograft recipients were divided into two groups: group 1 (n=94) received tacrolimus (.01 mg/kg per day), mycophenolate mofetil (MMF, 2 g/d), and steroids (30 mg/d); and group 2 (n=146) CsA (6 mg/kg per day), MMF (2 g/d), and steroids (30 mg/d). Antilymphocyte serum was administered in cases of acute tubular necrosis. The acute rejection rate was higher among group 2 (30.6%) compared with group 1 patients (12.2%) (P=.001). There were no significant differences between the groups in terms of age, gender, body surface area, serologic virus markers (in donor and recipient), baseline creatinine levels, cause of death, HLA incompatibilities, response to acute tubular necrosis, and number of dialysis sessions. We conclude that both immunosuppressive regimens are effective and safe in kidney transplantation. The survival rates of patients and grafts were similar, but the incidence and degree of acute rejection events were reduced in group 1; this finding may forecast a decreased incidence of chronic renal allograft nephropathy.     

肾移植术后急性体液性排斥反应的治疗

目的 总结肾移植术后急性体液性排斥反应中针对HLA抗体的检测和处理经验.方法 肾移植受者15例,术前行HLA分型、交叉配型和群体反应性抗体(PRA)的检测,术后采用他克莫司(或环孢素A)、霉酚酸酯和糖皮质激素预防排斥反应.15例于肾移植后1～14 d发生抗体介导的急性排斥反应(AMR),采用抗胸腺细胞球蛋白(100 mg/d,使用5 d)治疗,或将环孢素A转换为他克莫司,当PRA明显升高,且血清中出现供者特异性HLA抗体时,即行血浆置换(PP),共行1～5次,每次PP后静脉输注免疫球蛋白(IVIG)100～150 mg/kg,最后1次PP后给予WIG 200～500mg/kg.结果 术后出现抗供者特异性HLA Ⅰ类抗体者9例,抗HLAⅡ类抗体者4例,同时出现抗Ⅰ、Ⅱ类抗体者2例.14例的AMR逆转,1例术后发生移植肾功能恢复延迟,彩色多普勒超声波显示移植肾血流灌注差,于术后第10天切除移植肾.并行二行肾移植.2例AMR后并发急性肾小管坏死,透析后移植肾功能恢复正常.抗排斥反应治疗期间患者均未发生严重感染.随访12～52个月,1例因慢性移植肾肾病恢复血液透析治疗,1例死于心血管疾病,其余患者移植肾功能稳定.结论 将ATG、PP和IVIG联合应用能有效逆转AMR.     

Erythropoietin, but not the correction of anemia alone, protects from chronic kidney allograft injury

Anemia can contribute to chronic allograft injury by limiting oxygen delivery to tissues, particularly in the tubulointerstitium. To determine mechanisms by which erythropoietin (EPO) prevents chronic allograft injury we utilized a rat model of full MHC-mismatched kidney transplantation (Wistar Furth donor and Lewis recipients) with removal of the native kidneys. EPO treatment entirely corrected post-transplant anemia. Control rats developed progressive proteinuria and graft dysfunction, tubulointerstitial damage, inflammatory cell infiltration, and glomerulosclerosis, all prevented by EPO. Normalization of post-transplant hemoglobin levels by blood transfusions, however, had no impact on chronic allograft injury, indicating that EPO-mediated graft protection went beyond the correction of anemia. Compared to syngeneic grafts, control allografts had loss of peritubular capillaries, higher tubular apoptosis, tubular and glomerular oxidative injury, and reduced expression of podocyte nephrin; all prevented by EPO treatment. The effects of EPO were associated with preservation of intragraft expression of angiogenic factors, upregulation of the anti-apoptotic factor p-Akt in tubuli, and increased expression of Bcl-2. Inhibition of p-Akt by Wortmannin partially antagonized the effect of EPO on allograft injury and tubular apoptosis, and prevented EPO-induced Bcl-2 upregulation. Thus non-erythropoietic derivatives of EPO may be useful to prevent chronic renal allograft injury.     

Kidney transplantation after liver transplantation from the same donor: four cases of successful steroid withdrawal

BACKGROUND: Administration of corticosteroids to kidney recipients has hampered the complete clinical success of kidney transplantation. Because most organ transplantation in Japan is living-related, we had the experience of performing kidney transplantation (KT) after liver transplantation (LT) from the same donor in four patients and successfully withdrew corticosteroid administration. METHODS: Three pediatric and one adult patient received kidney allografts from 3 to 10 months after LT from the same donor. The immunosuppressive regimen consisted of a corticosteroid and tacrolimus. The steroid was withdrawn after KT in all four patients. After complete withdrawal of the steroid, DNA was extracted from two recipients and examined by polymerase chain reaction to detect microchimerism. A mixed lymphocyte reaction (MLR) and cell-mediated lymphocytotoxicity assay (CML) were performed to test for donor-specific hyporesponsiveness. RESULTS: Steroid withdrawal was successfully accomplished after KT in every patient. No steroid-withdrawal-associated complications were observed. In the three pediatric patients, remarkable catch-up growth was observed after steroid withdrawal. In the two patients tested, donor DNA was not detected by polymerase chain reaction, suggesting the absence of microchimerism. MLR and CML showed that recipient lymphocytes reacted against donor lymphocytes at the same level as against the third-party lymphocytes. CONCLUSION: Steroid withdrawal was successfully achieved in four kidney recipients who had received a liver allograft from the same donor. The MLR and CML findings indicated the absence of donor-specific hyporesponsiveness in vitro. Although the precise mechanism is not yet clear, KT after LT from the same donor should be considered as a method that allows steroids to be withdrawn from the immunosuppressive regimen of KT.