Risk factors for the development of chronic cyclosporine-nephrotoxicity

Ninety CSA-treated kidney transplants recipients entered the study. The patients were allocated to three groups based on serum creatinine at 12 months and kidney biopsy findings: control group (serum creatinine less than 177 mumol/l), rejection group (verified by biopsy, serum creatinine greater than 177 mumol/l), nephrotoxicity group (verified by biopsy, serum creatinine greater than 177 mumol/l). Thirty variables were systematically evaluated. The following parameters had a predictive value for the development of chronic CSA-nephrotoxicity: number of CSA-induced episodes of acute deterioration of renal function, CSA trough level (day 0-30, day 31-90), number of unexplained episodes of acute deterioration of renal function, number of nephrotoxic drugs, number of rejection treatments, number of rejection episodes and primary poor renal function. The results indicate that all factors leading to acute renal failure, favor the development of CSA-nephrotoxicity.     

Outcome of renal transplants with impaired renal function at 6 months

At 6 months after kidney transplantation 59 adults with impaired renal function were divided into three groups according to their serum creatinine level: group I 150-199 mumol/l; group II 200-299 mumol/l; and group III greater than or equal to 300 mumol/l. These patients were followed up for 5 years or to graft loss when it became apparent that the eventual outcome was related to the degree of renal impairment at 6 months. Age of donor and age of recipient did not have a bearing on the eventual outcome nor did the frequency of acute tubular necrosis or rejection episodes. Patients with severely impaired renal function with serum creatinine levels greater than or equal to 300 mumol/l have a poor outlook but there are no particular prognostic features on which to base a forecast for the individual patient.     

Withdrawal of mycophenolate mofetil in stable renal transplant recipients

BACKGROUND: Mycophenolate mofetil (MMF) has been demonstrated to decrease episodes of acute rejection in renal transplant recipients during the first year after transplantation. The utility of MMF after 1 year is less clear. METHODS: Forty-five stable renal transplant recipients on maintenance therapy of cyclosporine microemulsion, MMF, and prednisone had MMF withdrawn at approximately 1 year after transplantation. A matching concurrent group of 45 stable renal transplant recipients served as the case control group. RESULTS: Two of 45 patients in the MMF withdrawal group suffered an acute rejection episode as opposed to 1 of 45 in the control group. Both patients who rejected in the withdrawal group had adequate cyclosporine levels and had no recent decrease in prednisone dose. There was no evidence of an increased incidence of proteinuria or increased creatinine levels in the MMF withdrawal group. CONCLUSION: In general, withdrawal of MMF in stable renal transplant recipients is well tolerated. No increased risk of rejection could be demonstrated in this patient group. A larger study will be needed to confirm our result.     

The selective use of basiliximab versus thymoglobulin in combination with sirolimus for cadaveric renal transplant recipients at low risk versus high risk for delayed graft function

BACKGROUND: We previously reported that the use of basiliximab together with sirolimus permits a window of recovery from delayed graft function before the introduction of reduced-dose cyclosporine. The present study reviews our experience with the substitution of thymoglobulin for basiliximab as induction therapy for recipients at increased risk for early acute rejection episodes. METHODS: We retrospectively reviewed 145 cadaveric renal allograft recipients who received either basiliximab (n=115) or thymoglobulin (n=30) in combination with sirolimus and prednisone, followed by delayed introduction of reduced doses of cyclosporine. Recipients were stratified as high immune responders if they were African American, a retransplant recipient, or a recipient with a panel-reactive antibody greater than 50%. All other recipients were considered low immune responders. RESULTS: Basiliximab-treated high immune responders exhibited a higher incidence of acute rejection episodes (26%) than either basiliximab-treated low immune responders (10%, P=0.04) or thymoglobulin-treated high immune responders (3%, P=0.01). The median time to initiation of cyclosporine was 12 days; cyclosporine was initiated when the serum creatinine level was 2.5 mg/dL or less. Patients with early return of renal function displayed a lower incidence of acute rejection episodes than those with later recovery of function (P=0.003). High immune responders treated with basiliximab expressed a higher mean serum creatinine level at 3 months (P<0.01), 6 months (P=0.02) and 12 months (P=0.01) than either low immune responders treated with basiliximab or high immune responders treated with thymoglobulin. CONCLUSION: A strategy combining sirolimus with basiliximab for low-immunologic risk recipients and thymoglobulin for high-risk recipients leads to prompt recovery of renal function with a low risk of acute rejection episodes.     

The utility of cyclosporine weaning in renal transplantation.

Abrupt conversion of cyclosporine immunosuppression to conventional treatment with azathioprine and prednisone avoids long-term cyclosporine nephrotoxicity, albeit at the cost of a 20% to 40% rejection rate. The authors investigated the benefits and risks of a cyclosporine weaning protocol in 24 cadaveric and 9 live donor kidney recipients treated with a sequential quadruple immunosuppressive protocol. In cadaver kidney recipients, slow tapering of cyclosporine resulted in a 19% (p less than 0.001) improvement in the glomerular filtration rate, as estimated by the inverse ratio of the plasma creatinine concentration. Cadaver kidney recipients were stratified according to graft function (GFR ratio greater than 0.76, less than 0.76) at the of cyclosporine discontinuation. In 12 patients with well-functioning grafts, a 24% improvement was observed, whereas in 12 patients with poor graft function, the gain was limited to 13%. Patients with limited graft function tended to have more acute rejection episodes before cyclosporine weaning (0.92 +/- 0.64 versus 0.42 +/- 0.64, not significant). When the 24 cadaver kidney recipients were stratified according to onset of graft function after transplantation (days to plasma creatinine of 250 mumol/L), need for dialysis, panel reactive antibodies (PRA), and duration of cyclosporine treatment, no significant differences in graft function were observed at the onset or end of cyclosporine weaning. Acute graft rejection before cyclosporine weaning was the only variable associated with a significantly lower estimated glomerular filtration rate ratio at the end of cyclosporine treatment (0.83 +/- 0.11 versus 0.67 +/- 0.16, p less than 0.01). Weaning of cyclosporine was associated with a minimal risk of acute graft rejection. A single patient with stable graft function at the onset of the weaning process experienced an acute but reversible rejection episode 2 months after cyclosporine was discontinued. In summary, gradual weaning of cyclosporine improves graft function, and eliminates the excessive risk of acute graft rejection without the need for additional corticosteroid treatment.     

肾移植术后中远期急性排斥反应临床研究

目的探讨肾移植术后中远期移植肾急性排斥反应(AR)发生影响因素及移植肾生存情况。 方法回顾性分析浙江大学医学院附属第一医院肾脏病中心2018年1月至2019年12月因血清肌酐水平升高而接受移植肾病理活检并确诊移植肾AR受者临床资料,共纳入43例受者,其中急性抗体排斥反应组17例,急性T细胞排斥反应组26例;同时纳入同期(2周内)肾移植且移植肾功能正常的39例受者为对照组。正态分布计量资料比较采用配对t检验或单因素方差分析。计数资料比较采用χ²检验或Fisher确切概率法。采用Kaplan-Meier进行生存分析,并采用log-rank进行比较。P<0.05为差异有统计学意义。 结果急性抗体排斥反应组HLA-A错配2个比例(4/17)高于对照组(1/39),差异有统计学意义(P＝0.026)。急性抗体排斥反应组和急性T细胞排斥反应组AR发生时和末次血清肌酐和估算肾小球滤过率(eGFR)均高于AR发生前(P均<0.05);急性抗体排斥反应组和急性T细胞排斥反应组AR发生时和末次血清肌酐和eGFR均高于对照组(P均<0.05);急性抗体排斥反应组进入慢性肾脏病(CKD)-4期受者比例低于急性T细胞排斥反应组(χ²＝5.73,P<0.05);急性T细胞排斥反应组进入CKD-4期受者比例以及急性抗体排斥反应组移植肾失功比例均高于对照组(χ²＝17.727和9.882,P均<0.05)。AR发生时急性抗体排斥反应组和急性T细胞排斥反应组受者均接受PRA检测,前者PRA-Ⅰ和PRA-Ⅱ阳性比例分别为41.2%(7/17)和88.2%(15/17),均高于后者[11.5%(3/26)和26.9%(7/26)],差异均有统计学意义(P＝0.042,P<0.001)。急性抗体排斥反应组、急性T细胞排斥反应组及对照组术后分别有13、24和38例受者应用他克莫司。发生AR时,急性抗体排斥反应组他克莫司血药浓度[(3.72±0.76)ng/mL]与急性T细胞排斥反应组[(3.37±0.86)ng/mL]均低于对照组[(5.73±1.25)ng/mL],差异均有统计学意义(P均<0.05);急性抗体排斥反应组与急性T细胞排斥反应组他克莫司血药浓度均低于发生AR前[(6.27±1.18)和(6.33±1.63)ng/mL],差异均有统计学意义(t＝7.120和6.216,P均<0.05)。急性抗体排斥反应组4例受者应用以环孢素为基础的免疫抑制方案,其中3例术后33、36和55个月环孢素血浓度分别为112.4、138.3和7.0 ng/mL,均低于要求血药浓度。急性T细胞排斥反应组2例应用环孢素受者术后16和177个月环孢素血药浓度分别为43.2和24.6 ng/mL,均低于要求血药浓度。随访至2021年6月30日,急性抗体排斥反应组移植肾生存率低于对照组(χ²＝8.738,P<0.05)。 结论HLA-A位点错配及他克莫司低血药浓度是肾移植术后中远期诱发AR的重要原因。急性抗体介导排斥反应是移植肾生存重要影响因素。     

Long-term beneficial effect of tacrolimus conversion on renal transplant recipients

OBJECTIVE: Acute rejection, chronic allograft nephropathy, and cyclosporine (CsA) toxicity remain serious problems for renal transplant recipients and may lead to graft loss. We retrospectively analyzed 34 patients whose biopsies revealed acute and/or chronic allograft rejection, or CsA nephrotoxicity, and who converted from CsA to tacrolimus. PATIENTS AND METHODS: From July 1996 through September 2003, CsA was converted to tacrolimus in 34 renal transplant recipients (26 male, 8 female) with renal biopsy at our hospital. Blood pressure and serum creatinine levels were checked monthly and serum cholesterol, triglyceride, and glutamic-pyruvic transaminase (GPT) levels were checked every three months. RESULTS: A consistently stable and better function after conversion was obtained in a significant portion (24, 71%) of patients. A statistically significant decline in serum creatinine and an improvement in the glomerular filtration rate were found at 3 m, 6 m, 12 m, 36 m, and 72 m after tacrolimus conversion. In 85.7% (12/14) of patients with acute rejection and in 35.7% (5/14) of patients with chronic allograft nephropathy (concomitant with acute rejection in 5), improved or stabilized graft function was noted. In addition, the systolic blood pressure and diastolic BP dropped significantly (P<0.05), while there was no significant change in cholesterol, triglyceride, and GPT levels. CONCLUSION: The beneficial effect of tacrolimus conversion on patients with acute rejection, chronic allograft nephropathy, or CsA nephrotoxicity was demonstrated in long-term follow up. The improvement in both renal function and blood pressure may be of paramount importance in reducing long-term cardiovascular morbidity and mortality.     

Improved renal function in sirolimus-treated renal transplant patients after early cyclosporine elimination

BACKGROUND: Sirolimus (Rapamune; SRL) in combination with cyclosporine (CsA) reduces the incidence of acute rejection episodes in renal allograft recipients. This study evaluated whether renal function could be improved by elimination of CsA from an SRL-based regimen. METHODS: This phase 2, open-label, controlled, randomized study was conducted at 17 centers in the United States and Europe. Two hundred forty-six first cadaveric renal allograft recipients were enrolled, and 197 were randomized to full-dose CsA (microemulsion) plus fixed-dose SRL (2 mg/day; group A, n=97) or reduced-dose CsA plus concentration-controlled SRL (troughs 10-20 ng/mL; group B, n=100). Most patients with acute tubular necrosis-delayed graft function that resolved later than posttransplantation day 7 were not randomized but were assigned to a third group (nonrandomized, n=49) and received up to 5 mg per day of SRL as part of their individualized treatment regimen. All patients received standard doses of corticosteroids. At the end of posttransplantation month 2, eligible patients (those not treated for rejection within 3 weeks) in group B had CsA tapered and eliminated over the subsequent 4 to 6 weeks. RESULTS: At 12 months after transplantation, renal function was significantly better in the CsA-elimination arm. In patients who were on therapy and who had not experienced an acute rejection episode before month 6, serum creatinine level was significantly lower (1.38 mg/dL vs. 1.82 mg/dL, P < 0.001) and calculated glomerular filtration rate (Nankivell method) was significantly higher (73.5 mL/min vs. 57.1 mL/min, P < 0.001) in group B than in group A. In the intention-to-treat population, rates of biopsy-confirmed acute rejection at 12 months were similar between groups A and B (18.6% vs. 22.0%, respectively; P = 0.598). In addition, graft survival (92.8% and 95.0%) and patient survival (96.9% and 96.0%) rates at 12 months were not significantly different between groups A and B, respectively. Furthermore, there were no significant differences between black and nonblack recipients within treatment groups in terms of rejection rates and graft survival at 12 months. Black recipients in group B had better serum creatinine levels at 12 months compared with black recipients in group A (1.55 mg/dL vs. 2.69 mg/dL, respectively, P = 0.011), as did nonblack recipients in group B compared with nonblack recipients in group A (1.53 mg/dL vs. 1.75 mg/dL, respectively, P = 0.055). Black patients in group A had higher mean serum creatinine levels (2.69 mg/dL) than nonblack patients in group A (1.75 mg/dL, P = 0.028). Hypertension, edema, hypomagnesemia, and dyspnea were reported significantly less frequently in patients randomly assigned to undergo CsA elimination compared with patients in group A (P < 0.05); group B patients had a significantly greater (P < 0.05) incidence of abnormal liver function tests, diarrhea, hypokalemia, and thrombocytopenia. CONCLUSION: Concentration-controlled SRL with early elimination of CsA is safe and results in improved renal function. Reduced exposure to CsA does not result in a clinically significant increase in the incidence of acute rejection episodes. This is true for both black and nonblack recipients. SRL may be used to reduce the exposure of renal allograft recipients to the nephrotoxic effects of CsA.     

Use of anti-CD25 monoclonal antibody in combination with rapamycin to eliminate cyclosporine treatment during the induction phase of immunosuppression.

BACKGROUND: Cyclosporine and tacrolimus are associated with drug-induced renal dysfunction that may exacerbate recovery from ischemic injuries during the first month posttransplant. We sought to use anti-CD25 (anti-interleukin-2 receptor) monoclonal antibodies in combination with sirolimus (rapamycin) to avoid cyclosporine therapy during the early postoperative period in six renal transplant recipients deemed to be at high risk for delayed graft function. METHODS: Six consecutive patients deemed to be at high risk for delayed graft function were treated with rapamycin (2-12 mg/day), anti-CD25 monoclonal antibodies, and steroids, withholding inception of cyclosporine therapy until the serum creatinine fell below 3.0 mg/dl. RESULTS: During the first 2 months posttransplant, none of the patients displayed clinical or histopathological evidence of acute allograft rejection episodes, cytokine release syndrome, or hypersensitivity reactions. None of the patients received even empiric bolus or high-dose steroid therapy for a presumed rejection episode. All patients recovered renal graft function within 8 weeks posttransplant. To date all patients have stable renal graft function. Five patients have serum creatinine levels between 0.8 to 1.3 mg/dl at 6 months and the other patient has a serum creatinine level of 1.7 mg/dl at present follow-up of 2 months posttransplant. CONCLUSION: During the early posttransplant period anti-CD25 monoclonal antibodies combined with rapamycin and steroids offer a promising baseline therapy to avoid cyclosporine exposure and facilitate recovery from ischemic/reperfusion injuries.     

Timing of cyclosporine administration in patients with delayed graft function

Cyclosporine in renal transplant recipients with delayed graft function (DGF) has been reported to decrease graft survival and prolong both DGF and hospitalization. In some centers, antilymphocyte globulin (ALG) has been used perioperatively to obviate these problems, but ALG is associated with increased viral infections. In this study, first cadaver transplant recipients with a fall in serum creatinine level of greater than or equal to 30% in the first 24 hr were started on prednisone (P) and cyclosporine (Group 1, n = 18). Those whose creatinine level did not fall were started on P and azathioprine (Group 2, n = 23) and switched to P and cyclosporine when serum creatinine fell 30%. One-year patient survival was 98%. One-year graft survival was 83% for both Groups 1 and 2 (NS). Results were compared to historical controls with DGF who received P and cyclosporine (Group 3, n = 19). Patients with DGF and requiring dialysis had fewer dialyses (P less than 0.05) and a shorter hospital stay (P less than 0.05) if started on azathioprine, as compared to those started on cyclosporine. Patients with DGF had a higher serum creatinine at 12 months than those with immediate function (P less than 0.05). We conclude that withholding cyclosporine until DGF is resolving decreases the duration of dialysis, decreases hospital stay, and without the use of prophylactic ALG, is associated with graft survival equivalent to that in patients with immediate function.     

Is 3-hour cyclosporine blood level superior to trough level in early post-renal transplantation period?

PURPOSE: Cyclosporine dose is traditionally based on trough blood levels. Cyclosporine trough blood level correlates poorly with acute rejection and cyclosporine nephrotoxicity after renal transplantation. We determined whether cyclosporine blood level at any other time point is superior to cyclosporine trough blood level as a predictor of acute rejection and cyclosporine nephrotoxicity. MATERIALS AND METHODS: Cyclosporine blood level was measured before (trough), and 1, 2, 3 and 4 hours after the dose in 156 initial renal transplant cases 2 to 4 days after the initiation of cyclosporine micro-emulsion formula administration. The cylosporine micro-emulsion dose was based on cyclosporine trough blood level targeting 250 to 400 microg./l. RESULTS: Regression analysis revealed that only delayed graft function (p = 0.007) and cyclosporine blood level after 3 hours (p = 0.008) predicted acute rejection. Mean cyclosporine trough blood level plus or minus standard error was not significantly different in patients with and without acute rejection (293+/-21 versus 294+/-11 microg./l.). Mean cyclosporine blood level after 3 hours was significantly lower in patients with acute rejection (1,156+/-90 versus 1,421+/-50, p = 0.008). Cases were divided into tertiles at levels after 3 hours (1,100 and 1,500 microg./l.). The group in which the level after 3 hours was less than 1,100 microg./l. had the highest acute rejection rate (22 of 50 patients, 44%) and a cyclosporine nephrotoxicity rate of 13% (7 of 52 patients). The group in which the level after 3 hours was 1,100 to 1,500 microg./l. had the lowest acute rejection rate (5 of 46 patients, 11%) without increased cyclosporine nephrotoxicity (7 of 52 patients, 13%). A level after 3 hours of greater than 1,500 microg./l. was associated with a rejection rate of 15% (7 of 47 patients) but significantly higher cyclosporine nephrotoxicity (16 of 52 patients, 30%). CONCLUSIONS: Cyclosporine blood level after 3 hours in the early post-transplantation period is associated with acute rejection and cyclosporine nephrotoxicity. A cyclosporine blood level range after 3 hours of 1,100 to 1,500 microg./l. is associated with an optimal outcome. Our data suggest that cyclosporine blood level after 3 hours may represent a better method of monitoring cyclosporine micro-emulsion dose than cyclosporine trough blood level. This hypothesis must be further studied in randomized trials.     

Prospective study of the value of ultrasound measurements in the diagnosis of acute rejection following renal transplantation

In this prospective study we have used ultrasonographic measurements of the cross-sectional area of transplanted kidneys, as an objective assessment of graft size, for diagnosis of acute rejection episodes. Sixty episodes of acute graft dysfunction (serum creatinine rise of greater than or equal to 30 mumol/l) were studied in 40 patients. Tru-Cut biopsy under ultrasound control was performed in all cases and 36 episodes of acute cellular rejection were identified. An increase in graft cross-sectional area of greater than or equal to 10 per cent was defined as a positive scan, indicative of an acute rejection episode. Using these criteria, ultrasound correctly diagnosed rejection in 29 out of 36 cases (sensitivity 81 per cent) and there were four false positive results (specificity 83 per cent). The investigation had a predictive value of 88 per cent when positive and 74 per cent when negative.     

Increased serum beta 2 microglobulin during rejection, cyclosporine-induced nephrotoxicity, and cytomegalovirus infection in renal transplant recipients

In 83 renal transplant recipients, serum beta 2 microglobulin (beta 2m) levels were significantly elevated during pretransplant uremia, rejection, cyclosporine-induced nephrotoxicity, and infections. In patients with normal serum creatinine, 74% had elevated serum beta 2m levels. None of the cyclosporine-treated patients had normal levels of beta 2m. Patients with stable renal allograft function receiving cyclosporine showed significantly higher serum beta 2m (P less than 0.001) and serum creatinine (P less than 0.01) levels than azathioprine treated patients. Patients with an irreversible rejection showed significantly higher serum concentrations of beta 2m than patients experiencing a reversible rejection (P less than 0.001). During cytomegalovirus (CMV) infection the serum beta 2m levels were elevated compared with other infections (P less than 0.001), while the serum creatinine was not. However, infected patients had higher serum levels of beta 2m and creatinine than patients with stable renal allograft function (P less than 0.001). Serum beta 2m may therefore be useful in the early diagnosis of CMV infection. To conclude, serum beta 2m levels cannot distinguish between rejection, cyclosporine nephrotoxicity, or infection.     

Immunopathological patterns in long-term renal allografts

Forty-eight consecutive core needle biopsies obtained 12-158 months after transplantation from 48 human renal allografts were analyzed. A conventional histological investigation and an immunohistochemical analysis of various markers of the immune system were performed, as well as cytological analyses of simultaneously obtained fine-needle aspiration biopsies. Findings were compared in grafts with excellent or reduced function and in patients who were immunosuppressed with azathioprine or cyclosporine. All the patients with excellent renal graft function (serum creatinine level less than or equal to 120 mumol/L) showed a normal picture with respect to both FNAB pattern and immunohistology, irrespective of the type of immunosuppression. Thus, the presence of inflammatory cell infiltration in a long-term renal graft suggests a pathological process of potential clinical significance. Biopsies from CsA-treated patients with reduced renal graft function (serum creatinine greater than 120 mumol/L) showing either a normal picture or focal interstitial fibrosis on histological examination were also usually normal with respect to both FNAB cytology and the immunohistological pattern. Five of 36 biopsies with reduced function showed an immunohistochemical pattern with signs of immune activation indistinguishable from those seen in early acute rejection. In cases with histological signs of chronic rejection, the immunopathological pattern varied, which suggests that different pathogenetic mechanisms were involved.     

One-year posttransplant renal function is a strong predictor of long-term kidney function: results from the Neoral-MOST Observational Study

BACKGROUND: Peritransplant risk factors influence short-term and long-term graft survival, and 1-year serum creatinine is known to predict long-term graft survival. To examine interrelationships between risk factors, renal function at 1 year, and long-term graft function in patients maintained on cyclosporine, we analyzed data collected from 10,692 de novo or maintenance renal transplant recipients in an ongoing international, prospective, observational study--Neoral-MOST (Multinational Observational Study in renal Transplantation). The effect of donor age, delayed graft function, acute rejection, donor type, panel-reactive antibodies, and previous graft on 1- and 5-year renal function and their relationship to 1-year serum creatinine was assessed. RESULTS: Donor age, delayed graft function, acute rejection, and donor type significantly increased the risk for serum creatinine > 130 micromol/L at 1 year posttransplant, and 1-year serum creatinine was the strongest predictor of 5-year renal function. After adjustment for 1-year serum creatinine, an ongoing influence was observed for donor age, donor type, and previous graft. Delayed graft function and acute rejection had a significant effect on serum creatinine at year 1 but no additional impact on long-term graft function. CONCLUSIONS: Serum creatinine at 1 year is influenced by risk factors known to affect overall graft survival and is predictive of 5-year renal graft function. The effects of delayed graft function and acute rejection appear to be limited to their influence on serum creatinine at 1 year, whereas donor type and previous graft predominantly affect later stages of graft life.     

Foscarnet nephrotoxicity: mechanism, incidence and prevention

Foscarnet is a pyrophosphate analogue that has been successfully used in severe cytomegalovirus (CMV) infections. Little is known of the incidence and mechanisms of foscarnet-induced nephrotoxicity as most data comes from recipients of renal allografts or from patients with severe underlying disease or with other nephrotoxic drugs. We have retrospectively analyzed the evolution of renal function after 56 courses of foscarnet. In addition, we have prospectively studied the protective effects of hydration on foscarnet nephrotoxicity (2.5 liters of saline/day during the night before the foscarnet therapy and throughout the course of treatment). Foscarnet-induced acute renal failure was defined as a rise in serum creatinine of at least 25% from the basal value. An increase in serum creatinine occurred in 37 cases out of the 56 courses of foscarnet (66%). The mean serum creatinine prior to foscarnet was 80.5 +/- 3.3 mumol/l and the mean increase was 190 +/- 28.3 mumol/l (range 80-1,000). Peak serum creatinine was higher than 200 and 300 mumol/l in 16 and 13 patients, respectively. Kidney obtained at autopsy from a 30-year-old male with AIDS, CMV pneumonitis and acute renal failure secondary to foscarnet administration showed an extensive tubular necrosis. In the group which was prospectively hydrated only 1 patient had an acute renal failure. The mean serum creatinine at the peak (96 +/- 4 mumol/l) and at the end of the treatment (83 +/- 4 mumol/l) was significantly lower (p less than 0.05) than in non hydrated patients. In conclusion, foscarnet is a highly nephrotoxic drug which induces acute tubular necrosis.(ABSTRACT TRUNCATED AT 250 WORDS)     

Long-Term Beneficial Effect of Tacrolimus Conversion on Renal Transplant Recipients

Objective. Acute rejection, chronic allograft nephropathy, and cyclosporine (CsA) toxicity remain serious problems for renal transplant recipients and may lead to graft loss. We retrospectively analyzed 34 patients whose biopsies revealed acute and/or chronic allograft rejection, or CsA nephrotoxicity, and who converted from CsA to tacrolimus. Patients and Methods. From July 1996 through September 2003, CsA was converted to tacrolimus in 34 renal transplant recipients (26 male, 8 female) with renal biopsy at our hospital. Blood pressure and serum creatinine levels were checked monthly and serum cholesterol, triglyceride, and glutamic-pyruvic transaminase (GPT) levels were checked every three months. Results. A consistently stable and better function after conversion was obtained in a significant portion (24, 71%) of patients. A statistically significant decline in serum creatinine and an improvement in the glomerular filtration rate were found at 3 m, 6 m, 12 m, 36 m, and 72 m after tacrolimus conversion. In 85.7% (12/14) of patients with acute rejection and in 35.7% (5/14) of patients with chronic allograft nephropathy (concomitant with acute rejection in 5), improved or stabilized graft function was noted. In addition, the systolic blood pressure and diastolic BP dropped significantly (P< 0.05), while there was no significant change in cholesterol, triglyceride, and GPT levels. Conclusion. The beneficial effect of tacrolimus conversion on patients with acute rejection, chronic allograft nephropathy, or CsA nephrotoxicity was demonstrated in long-term follow up. The improvement in both renal function and blood pressure may be of paramount importance in reducing long-term cardiovascular morbidity and mortality.     

Graft function, cardiovascular risk factors, and sex hormones in renal transplant recipients on an immunosuppressive regimen of everolimus, reduced dose of cyclosporine, and basiliximab

A prospective, randomized trial evaluated the combination of everolimus of 1.5 or 3 mg/d with steroids, basiliximab, and low-dose cyclosporine (CsA) adjusted by C2 monitoring in 256 renal transplant recipients. CsA C2 target levels, initially set at 600 ng/mL, were tapered over time posttransplant. The median serum creatinine concentrations were 130 mumol/L in both sirolimus groups (1.5 and 3 mg/d) at 6 months. Biopsy-proven acute rejection (BPAR) occurred in 13.7% and 15.1% of patients in the 1.5 and 3 mg/d groups, respectively. The incidence of BPAR was significantly higher among patients with everolimus trough levels < 3 ng/mL. Posttransplant diabetes mellitus occurred rarely, and blood pressure control appeared favorable; however, serum cholesterol levels were increased by approximately 50%, and serum triglycerides by approximately 100%. Serum testosterone concentrations increased after renal transplantation in both everolimus groups. Concentration-controlled everolimus therapy combined with low-dose CsA provides effective protection against rejection with good renal function and safety profiles.     

Monitoring of serum neopterin levels in renal transplant recipients: increased values during impaired renal function and cytomegalovirus infection

In 92 renal transplant recipients, serum or plasma levels of neopterin were significantly elevated during pretransplant uremia, rejection, cyclosporin A induced nephrotoxicity and cytomegalovirus (CMV) infections. In patients with normal serum creatinine (less than 115 mumol/l) 71% had elevated serum neopterin levels. None of 19 cyclosporin A treated patients with stable renal function had a normal level of neopterin compared to 50% for patients treated with azathioprine (p less than 0.05). Due to the dependency on renal function the serum levels of neopterin could not distinguish between rejection and cyclosporin A induced nephrotoxicity. Marked increases in neopterin levels were seen during infections and especially during CMV infection. Determination of neopterin levels may be helpful in the diagnosis of CMV infection.     

Mycophenolate mofetil but not the type of calcineurin inhibitor (cyclosporine vs tacrolimus) influences the intragraft mRNA expression of cytokines in human kidney allograft biopsies by in situ RT-PCR analysis

The aim of the study was to assess the molecular background of the alloimmune response by the detection of low-abundance mRNA of cytokines in 34 core needle biopsies from kidney allografts with histopathological findings of acute rejection (AR). Recipients were immunosuppressed with a calcineurin inhibitor (CNI), cyclosporine or tacrolimus, and prednisone and azathioprine or mycophenolate mofetil (MMF). Tubular and glomerular expression of IL-2, IL-6, IL-10, IFN-gamma, TGF-beta1, and PDGF-B mRNA were assessed using semiquantitative evaluations of RT-PCR in situ on paraffin tissue sections. This procedure resulted in light microscopy visualization of granular precipitates at the sites of the corresponding mRNA chains. The tubular expression of mRNA for IL-6 and TGF-beta1 was significantly lower in biopsies with AR (n = 34) obtained from patients treated with MMF (n = 12) than in biopsies obtained from patients treated with azathioprine (n = 22) (P < .02). Responsiveness to corticosteroids tended to be more frequent among the MMF group (11 of 12 recipients vs 15 of 22 recipients, P = ns). Moreover, 8 of 12 recipients in the MMF-treated group displayed serum creatinine levels equal or less than 167 mmol/L 1 year after biopsy compared to 7 of 22 recipients in the azathioprine-treated group. There was no significant difference between the groups that had or had not received corticosteroids or between those treated with each type of CNI. These results suggest stronger inhibition of humoral responses and down-regulation of fibrosis by MMF among recipients with AR.