Randomized study comparing cyclosporine with azathioprine one year after renal transplantation-15-year outcome data

BACKGROUND: The introduction of cyclosporine (CsA) improved 1-year graft survival and reduced the incidence of acute rejection episodes after renal transplantation compared to azathioprine (Aza). However, CsA has many side effects and reducing exposure of this drug after the first year may benefit long-term patient and graft survival. METHODS: We report 15-year outcome data from a single center, randomized controlled study comparing CsA withdrawal and conversion to Aza with continuation of CsA 1-year posttransplant. RESULTS: Two hundred sixteen patients who showed a serum creatinine less than 300 mumol/L with no acute rejection episodes in the preceding 6 months were enrolled (CsA 114, Aza 102). There was no difference in patient survival at 15 years: 62.4% in the CsA group and 64.4% in the Aza group (P=0.6). Fifteen-year transplant survival was 41.9% for the CsA group and 48.8% for the Aza group (P=0.8). Fifteen-year graft survival censoring for death with a functioning graft was 58% in the CsA group and 72% in the Aza group (P=0.5). Predictors of patient survival were younger recipient age (P<0.001) and lower systolic blood pressure at randomization (P=0.01). Predictors of graft survival were older recipient age (P<0.001) and better renal function at randomization (P=0.01). Assigned drug showed no effect on graft or patient survival. Patients assigned to CsA showed significantly worse renal function up to 10 years posttransplantation and required more anti-hypertensive treatment throughout the study period. CONCLUSION: In a selected group of patients, either Aza or low-dose CsA is safe and effective. Despite lower estimated glomerular filtration rate (eGFR) up to 10 years posttransplantation and increased use of anti-hypertensive agents, low-dose CsA was not associated with a worse patient or graft survival.     

Results of the Minnesota randomized prospective trial of cyclosporine versus azathioprine-antilymphocyte globulin for immunosuppression in renal allograft recipients

Between September 26, 1980 and June 8, 1984, 246 splenectomized, transfused renal allograft recipients were randomized to treatment with either cyclosporine (CsA)-prednisone (n = 131) or azathioprine (Aza)-prednisone-antilymphocyte globulin (n = 115). On December 31, 1984, actuarial patient survival rates at three years were 89% in the CsA group and 90% in the Aza group, and the corresponding graft survival rates were 82% and 79% (statistically insignificant differences). The results were also compared separately in diabetic and nondiabetic patients and in recipients of related and cadaver donor grafts; only in the subgroup of diabetic recipients of cadaver kidneys were the differences in graft survival rates significantly different between CsA- and Aza-treated patients. The incidence of posttransplant acute tubular necrosis was similar in CsA- and Aza-treated patients (33% v 27%), but the duration was significantly longer in CsA- than in Aza-treated recipients (15.7 +/- 18.4 v 7.7 +/- 3.0 days). Rejection episodes and infections (particularly CMV) occurred significantly less frequently in CsA- than in Aza-treated patients. Mean serum creatinine levels were significantly higher in CsA- than in Aza-treated recipients (2.0 +/- 0.6 v 1.5 +/- 0.5 mg/dl). Treatment of hypertension and hyperkalemia was required significantly more frequently in the CsA-treated patients than in the Aza-treated patients. Initial mean hospitalization time was significantly shorter in the CsA group than in the Aza group (15.6 +/- 9.5 v 19.8 +/- 10.7 days). In the CsA group, 19% of the patients were switched to Aza and 35% had Aza added to their regimen with a concomitant lowering of the CsA dose because of nephrotoxicity. The results of our randomized trial are at variance with those of others in that the graft survival rates in our trial were not different between CsA and Aza-treated patients, primarily because our conventionally-treated patients had a higher graft survival rate than in the other trials. The advantages of CsA (fewer rejection episodes, fewer infections, shorter hospitalization) outweigh the disadvantages (higher serum creatinine, more hypertension), and thus we believe it should be used in most renal allograft recipients, perhaps in combination with Aza so that a lower dose of CsA can be used and the side effects minimized--a regimen that we are currently evaluating.     

Amelioration of chronic renal allograft dysfunction in cyclosporine-treated patients by addition of azathioprine

Management of chronic renal allograft dysfunction in cyclosporine-prednisone treated renal allograft recipients remains problematic. We therefore initiated a protocol of azathioprine addition (1.0-1.5 mg/kg/day) to ongoing CsA/Pred therapy. Three groups were treated. Group A (n = 21) had chronic progressive renal dysfunction (serum creatinine greater than or equal to 2.5 mg/dl or more than 15% above baseline) four or more months after transplantation. Group B (n = 8) had frequent or severe rejection episodes occurring despite adequate CsA levels. Group C (n = 7) had constitutional side effects of CsA with or without renal dysfunction persisting despite drug taper or financial difficulty in affording CsA. Aza was initiated 17.8 +/- 2.8 months after transplantation in group A, the mean serum creatinine having risen from 2.55 +/- 27 mg/dl to 3.04 +/- .20 mg/dl (P = .07) over the six months preceding Aza initiation, despite stable and low therapeutic range HPLC whole-blood CsA levels (118 +/- 10 ng/ml vs. 133 +/- 11 ng/ml, P = NS). Renal function declined at a rate of -0.20 +/- .06 Cr1/year in the six-month period before addition of Aza, and then improved at a rate of 0.09 +/- .04 Cr-1/year after addition of Aza (P = .002). These changes in renal function occurred without a decrease in CsA levels (118 +/- 10 six months before Aza vs. 126 +/- 26 six months after Aza, P = NS). In group B Aza was initiated at 58 +/- 8 days after transplantation when mean sCr was 3.56 +/- .29 mg/dl and mean CsA level was 222 +/- 17 ng/ml. At least follow-up 12.7 +/- 2.0 months after addition of Aza, all group B grafts were functioning, mean sCr was 2.69 +/- .31 mg/dl (P = .09 compared with baseline), and mean CsA level was 128 +/- 34 ng/ml (P = .07 compared with baseline). Group C patients had addition of Aza at 43 +/- 19 months after transplantation when mean sCr was 2.97 +/- .60 and mean CsA level was 125 +/- 30 ng/ml; addition of Aza had no influence on the rate of decline in renal function in this group. Of these 36 patients, 6 received therapy for acute rejection over the entire follow-up period of 12.3 +/- 1.4 months after addition of Aza; 4 of these retain graft function. Infectious complications consisted of 2 urinary tract infections, 1 bacterial pneumonia, and one case of otitis media.(ABSTRACT TRUNCATED AT 400 WORDS)     

Long-term renal allograft function under maintenance immunosuppression with cyclosporin A or azathioprine: A single center, five-year follow-up study

Abstract. In order to evaluate long-term renal graft function, 149 cyclosporin A and prednisolone (CyA/P)-treated renal transplant recipients were compared with 119 azathioprine and prednisolone (Aza/P)-treated patients. Only patients who had a functioning graft for at least 1 year and who were maintained on their initial immunosuppressive protocol were included. The minimum follow-up period was 4 years. Renal graft function was estimated by yearly determinations of serum creatinine and creatinine clearance. The CyA/P-treated patients had a significantly higher serum creatinine and a significantly lower creatinine clearance at every point in time post-transplantation than Aza/P-treated patients ( P < 0.001). The evolution of renal graft function, as reflected in the line of regression for serum creatinine and creatinine clearance versus time, was estimated for each individual patient. There was an almost stable renal function, as assessed by the median of the slopes of the regression line for serum creatinine versus time in both groups. The median increase in serum creatinine was only 1.4 μmol/l per year for Aza/P-treated patients and 2.4 μmol/l per year for CyA/P-treated patients (difference NS). The median decline in creatinine clearance was 2.18 ml/min per 1.73 m²/year in the Aza/P group and 1.07 ml/min per 1.73 m²/year in the CyA/P group ( P = 0.05). In patients with a functioning graft for at least 5 years, creatinine clearance remained unchanged in both groups during the study period. In conclusion, renal graft function, as assessed by measurements of serum creatinine and creatinine clearance, remained essentially unchanged for at least 5 years after transplantation, regardless of the immunosuppressive protocol used. Thus, these data do not indicate a progression with time of the nephrotoxicity observed in CyA-treated patients.     

Evidence that addition of azathioprine improves renal function in cyclosporine-treated patients with allograft dysfunction

Several approaches have been attempted to manage renal allograft dysfunction in cyclosporine-prednisone (CsA-Pred)-treated patients. Conversion to conventional therapy and perioperative triple drug have been associated with high rates of acute rejection episodes, infections, or neoplasms. We report our experience in delayed addition of azathioprine (1-2 mg/kg/day) to CsA/Pred protocol in three groups of patients. Group I (n = 9) had chronic renal function deterioration due to chronic rejection; group II (n = 10) had repeated or severe acute rejection episodes despite adequate CsA levels; and group III (n = 8) had CsA toxicity despite drug tapering. In group I, serum creatinine (SCr) had risen from 2.2 +/- 0.9 to 2.9 +/- 0.7 mg/dl over the 6 months prior to Aza addition (P less than 0.05), renal function declining at a rate of -0.14 +/- 0.12 Cr-1/year. In the 6-month post-Aza, renal function improved at a rate of 0.06 +/- 0.06 Cr-1/year and during the entire follow-up at a rate of 0.04 +/- 0.12 Cr-1/year (P less than 0.05) with stable CsA levels (288 +/- 167 vs. 251 +/- 172 ng/dl, NS). In group II response was worse, though the rate of declining renal function prior to Aza (-0.10 +/- 0.10 Cr-1/year) was almost stopped after Aza. In group III there was very good response to Aza addition, as 7 out of 8 patients improved graft function (baseline SCr 2.5 +/- 0.7 mg/dl vs. 1.9 +/- 0.6 mg/dl at last follow-up, P less than 0.05), with significantly decreased CsA levels (480 +/- 97 vs. 268 +/- 120, P less than 0.05). One patient from group II died from pneumonia, and 6 patients (1 from group I and 5 from group II) lost their grafts. Fifteen patients improved graft function, and 9 worsened after addition of Aza. The bad-responders had significantly higher SCr at baseline compared with the good-responders (3.8 +/- 1.8 vs. 2.7 +/- 0.6 mg/dl, P less than 0.01). Amelioration of chronic graft dysfunction can be achieved by delayed addition of Aza to CsA-Pred in patients with chronic rejection or CsA toxicity. This is accompanied by low rate of acute rejection, good patient and graft survival, and low rate of infections. A worse outcome can be seen in patients with high-baseline SCr levels, suggesting the need for addition of Aza in the initial chronic graft dysfunction.     

Cyclosporine toxicity: the effect of combined therapy using cyclosporine, azathioprine, and prednisone

Forty-nine patients among 360 who received renal transplants under cyclosporine (CsA)/prednisone (Pred) immunosuppression required alteration of the immunosuppressive regimen because of intractable nephrotoxicity. Twenty-five patients, converted totally to azathioprine (Aza)/Pred, suffered intractable nephrotoxicity with no associated evidence suggesting ongoing rejection. The results with Aza/Pred conversion were disappointing because of an unacceptably high incidence of rejection and allograft loss. Twenty-four patients with intractable CsA nephrotoxicity were, therefore, treated using an alternative approach combining Aza with aggressive CsA dose reduction, and continued Pred therapy. All patients tolerated initiation of Aza without complication; allograft rejection was not common. Renal function improved for 23 of the 24 (96%) CsA/Aza/Pred patients with mean serum creatinine levels falling from 3.5 +/- 0.5 mg/dL to 2.2 +/- 0.4 mg/dL after a mean follow-up of 14 months (P less than .001). Among 18 patients observed at least 12 months, seven (39%) enjoyed serum creatinine values less than or equal to 2 mg/dL. Nine CsA/Aza/Pred-treated patients (37.5%) required hospitalization because of infectious complications, all of which resolved with temporary reduction of immunosuppression and specific antimicrobial therapy when indicated. One patient sustained acute allograft rejection as a result of patient noncompliance, and one patient on a seemingly appropriate CsA/Aza/Pred dose responded initially to steroid pulse antirejection therapy; however, renal function again worsened. Two patients developed progressive renal dysfunction due to chronic rejection, and returned to dialysis 13 and 17 months, respectively, following initiation of CsA/Aza/Pred. Overall, the actuarial graft survival for CsA/Aza/Pred-treated patients was 100% at 1 year, and 84% at 2 years.(ABSTRACT TRUNCATED AT 250 WORDS)     

Long-term renal allograft function under maintenance immunosuppression with cyclosporin A or azathioprine

In order to evaluate long-term renal graft function, 149 cyclosporin A and prednisolone (CyA/P)-treated renal transplant recipients were compared with 119 azathioprine and prednisolone (Aza/P)-treated patients. Only patients who had a functioning graft for at least 1 year and who were maintained on their initial immunosuppressive protocol were included. The minimum follow-up period was 4 years. Renal graft function was estimated by yearly determinations of serum creatinine and creatinine clearance. The CyA/P-treated patients had a significantly higher serum creatinine and a significantly lower creatinine clearance at every point in time posttransplantation than Aza/P-treated patients (P<0.001). The evolution of renal graft function, as reflected in the line of regression for serum creatinine and creatinine clearance versus time, was estimated for each individual patient. There was an almost stable renal function, as assessed by the median of the slopes of the regression line for serum creatinine versus time in both groups. The median increase in serum creatinine was only 1.4 mol/l per year for Aza/P-treated patients and 2.4 mol/l per year for CyA/P-treated patients (difference NS). The median decline in creatinine clearance was 2.18 ml/min per 1.73 m²/year in the Aza/P group and 1.07 ml/min per 1.73 m²/year in the CyA/P group (P=0.05). In patients with a functioning graft for at least 5 years, creatinine clearance remained unchanged in both groups during the study period. In conclusion, renal graft function, as assessed by measurements of serum creatinine and creatinine clearance, remained essentially unchanged for at least 5 years after transplantation, regardless of the immunosuppressive protocol used. Thus, these data do not indicate a progression with time of the nephrotoxicity observed in CyA-treated patients.     

Renal function after kidney transplantation in children. A comparison of conventional immunosuppression with cyclosporine

Clearance studies were performed in 32 transplanted children treated with CsA in combination with low-dose prednisolone (CsA group), and the results were compared with those of 29 children transplanted earlier and treated with azathioprine and prednisolone (CIS group). Serum creatinine and urea levels 6 weeks and 1 year after transplantation (Tx) were significantly higher in the CsA than in the CIS group. Clearance studies 6 weeks after Tx exhibited significantly lower rates in the CsA group: Cin = 47 +/- 16.5 versus 83 +/- 25 ml/min/1.73 sqm, CPAH = 271 +/- 110 versus 503 +/- 181 ml/min/1.73 sqm (P less than 0.001). The filtration fractions were not different (19.1 versus 17.1%). The tubular phosphate reabsorption per ml GFR (Tp/Cin) was only slightly lower in the CsA group (0.76 +/- 0.23 mumol/ml versus 0.93 +/- 0.29; P = 0.09). The endogenous glucose clearance rates were equally elevated in both groups and returned to normal after 1 year. The creatinine clearance (Ccr) had dropped in both groups by a mean for 13 ml/min/1.73 sqm between 6 weeks and 1 year after Tx. No correlation was found between the Ccr and the CsA blood levels, but Ccr was inversely correlated with the number of rejection episodes (r = -0.72, P = 0.001). In conclusion, renal allografts in CsA-treated children exhibited a significantly lower function than in CIS-treated children. The effect was related to the global kidney function without any signs of additional tubular toxicity and was apparent within the first weeks after Tx. Thereafter, the decline in graft function was comparable in both groups and could not be related to CsA treatment.     

Impact of long-term immunosuppression with cyclosporin A on serum lipids in stable renal transplant recipients

Abstract. To determine the impact of long-term immunosuppression on serum lipids in stable renal graft recipients we measured serum lipids and apolipoprotein B concentrations in 20 patients receiving therapy with cyclosporin (CsA) and low-dose prednisolone (CsA/P) and in 18 patients on therapy with azathioprine and maintenance steroids (Aza/P). The patients were matched for age, body mass index, primary renal disease and dose of prednisolone, but not for the duration in transplantation and serum creatinine concentration. Triglyceride concentrations were significantly higher in the CsA/P group than in Aza/P-treated patients: 2.62 ± 0.35 vs 1.62 ± 0.23 mmol/l ( P < 0.05). Similarly, total cholesterol (C) levels were significantly more elevated in the CsA/P recipients than in the other group: 7.4410.32 vs 5.84 ± 0.25 (F<0.02). CsA/P patients had higher serum levels of LDL-C (4.79 ± 0.20 vs 3.43 ± 0.19 mmol/l ( P < 0.001) and apolipoprotein B concentrations (191 ± 13 vs 128 ± 9 mg/dl; P < 0.001). CsA/P and Aza/P recipients had similar concentrations of HDL-C (1.73 ± 0.13 vs 1.52 ± 0.09 mmol/l; NS). We conclude that in stable renal graft recipients with good transplant function long-term immunosuppression with CsA/P is associated with a more atherogenic lipid status than therapy with Aza/P.     

A Prospective Randomised Comparative Study on the Influence of Cyclosporin and Azathioprine on Renal Allograft Survival and Function

To study the effectiveness and nephrotoxic side-effects of cyclosporinA (CsA) in renal transplant recipients, a prospective randomisedtrial was designed to compare CsA with azathioprine (Aza). Eachtreatment group consisted of 40 patients; in the CsA group,18 were randomly selected for conversion to Aza after 3 months.The 1-year graft survival for CsA-treated patients was 87% comparedwith 66% for the Aza group (P=0.033). Anti-rejection therapywas administrated to 78% of the patients in the Aza group and47% of those in the CsA group (P<0.01). There was no differencein the incidence of primary non-functioning kidneys, cytomegalovirusinfections, hypertension, or degree of proteinuria between thetwo treatment groups. At 3 months the mean creatinine clearance was 42±2 ml/min(mean±SEM) for the CsA group compared with 56±4ml/min for the Aza group (P<0.01), whereas the mean creatinineclearances at 6 months for both the converted and the non-convertedCsA-treated patients did not differ from that found in the Aza-treatedgroup. At 1 year, the mean creatinine clearance for CsA-treatedpatients who were converted to Aza was higher than that foundfor Aza treated patients (62±7 vs 50±6 ml/min;P<0.05). Furthermore, the increment in creatinine clearanceobserved after conversion from CsA to Aza at 3 months showeda linear relationship (r=0.9061) with the CsA trough levelsbefore discontinuation of the drug. This indicates that CsA treatment induces a dose-dependent,nephrotoxic side-effect which is probably reversible.     

Chronic cyclosporine-induced nephropathy in the rat. A medullary ray and inner stripe injury

Cyclosporine CsA nephrotoxicity was examined in male Sprague-Dawley rats with or without prior uninephrectomy, injected daily with 12.5 mg/kg CsA, and fed a salt-depleted or normal diet for 3-10 weeks. Control rats received the CsA vehicle. CsA induced a fall in creatinine clearance in salt-depleted rats, from 1.3 +/- 0.1 to 0.8 +/- 0.1 ml/min (P less than 0.001), and in normally fed rats from 1.8 +/- 0.2 to 1.0 +/- 0.2 ml/min (P less than 0.02). Vehicle treatment had no effect. The most striking morphologic changes were those of thick ascending limb cell atrophy with concomitant fibroblastic proliferation and collagen formation; these alterations were present in the inner stripe of the outer medulla and the medullary ray. The medullary-ray findings included S2-S3 degenerative changes as well and apparently correspond to the striped fibrosis described in human CsA nephropathy. The alterations were specific to the CsA group, progressive, and most severe in the salt-depleted, CsA-injected rats (on a scale of 0-4: 1.7 +/- 0.2 for medullary rays, and 2.0 +/- 0.2 for inner stripe, P less than 0.001). Morphologic changes predicted renal failure (r = 0.3, P less than 0.01 for cortical alterations, and r = 0.5, P less than 0.001 for medullary alterations). Prior uninephrectomy did not enhance these changes. Thus, chronic CsA administration impaired kidney function and induced morphologic alterations found in regions characterized by, and in nephron segments particularly vulnerable to, limited O2 availability. Salt depletion appears to accelerate the development of chronic CsA renal injury in the rat.     

Controlled cyclosporine conversion at three months after renal transplantation. Long-term results

The long-term results of conversion of cyclosporine to azathioprine and those of continuous CsA therapy were evaluated in a prospective study of 66 renal transplant patients who had been randomly assigned to each treatment group at 3 months following transplantation. The start point of the study was thus at 3 months posttransplant; no differences in the three-year patient and graft survival were found; these consisted of 97% and 94% in the converted group and 100% and 94% in the nonconverted group, respectively. The incidence of one or more antirejection treatments did not differ between the two groups at 3-12 months (16% vs. 17%) or after 12 months (12% vs. 9%). The incidence of hypertension at different intervals ranged from 79% to 100% in the group on continuous CsA therapy versus 50 to 58% in the converted patients. The degree of proteinuria in the 2 groups was not different at at 12 months. At 24 and 36 months the proteinuria (g/24 hr) was higher in the converted group (0.51 +/- 0.18 and 0.53 +/- 0.13; mean +/- SEM) versus the CsA group (0.15 +/- 0.04 and 0.21 +/- 0.09). At 3 years, the mean creatinine clearance for the patients converted to Aza was higher than that found for the continuously CsA-treated patients (67 +/- 8 and 59 +/- 6 ml/min; mean +/- SEM). This study shows that early CsA conversion to Aza gives a slightly better 3-year graft function, although not significantly different, compared with continuous CsA therapy without differences in patient or graft survival.     

Prevention of acute cyclosporine-induced renal blood flow inhibition and improved immunosuppression with verapamil

Pretreatment with calcium antagonists such as verapamil (VP) and isradipine prevents CsA-induced decrease in renal microcirculation in mice. Recently, in posttransplant cadaver renal transplant (CRT) recipients, we demonstrated a CsA-induced 70% reduction in renal parenchymal diastolic blood flow velocity (PDBFV). Using duplex Doppler scanning, this randomized study of forty CRT patients examines the effect of pretreatment with VP on renal blood flow velocity and posttransplant function. Patients with initially low PDBFV (less than 8.0 cm/sec) who received VP therapy prior to administration of CsA experienced prompt restoration of flow, and continued to improve during CsA administration. With CsA alone, PDBFV diminished from 8.9 +/- 2.4 (SD) to 5.3 +/- 2.7 cm/sec (P less than 0.002). Although blood CsA levels were significantly higher at 1, 4, and 7 days (68, 184, and 235 ng/ml, respectively), after CsA induction, during VP treatment than in control patients (39, 105, and 156 ng/ml, respectively) (P less than 0.001), with the same daily doses of CsA, serum creatinines at day 7 were lower during VP treatment (1.28 +/- 0.44 vs. 1.66 +/- 0.44 mg%) than in controls (P less than 0.01). When the glomerular filtration rate was less than 45 ml/min on day 1. VP-treated patients showed greater improvement in GFR at day 7 by 34.1 +/- 10.9 ml/min compared with the 18 +/- 13 ml/min in controls (P less than 0.02). Only 3 of the 22 VP patients had rejection episodes within 4 weeks, versus 10 of the 18 recipients randomized to no drug (P less than 0.005). We conclude that VP is beneficial in CRT because it improves renal blood flow characteristics and prevents CsA-induced inhibition of blood flow. VP also ameliorates CsA-induced acute nephrotoxicity, and is associated with improved immunosuppression and fewer early rejections.     

Renal handling of urate and the incidence of gouty arthritis during cyclosporine and diuretic use.

The incidence of gouty arthritis and the role of renal urate handling and diuretic use were studied in 85 cadaveric kidney graft recipients with a graft functioning for at least two years. The incidence of gout was 24% in patients using cyclosporine (CsA, n = 55); no patient using azathioprine (Aza, n = 23) had gout. In patients using CsA, the fractional urate clearance decreased between 1 and 3 months after transplantation, thereafter remaining stable at a significantly lower level than in patients using Aza, pointing toward a specific effect of CsA on tubular urate handling. This impaired fractional urate clearance was not reversible up to 18 months in 7 patients after conversion from CsA to Aza, suggesting irreversible tubular damage. Multiregression analysis showed that the impaired fractional urate clearance and the use of furosemide were significant contributors to the occurrence of gout in patients using CsA.     

Evaluation of kidney function in renal transplant patients receiving long-term cyclosporine

We prospectively assessed renal function in a group of 29 renal transplant patients receiving cyclosporine (CsA) in order to determine the course of their renal function over time and the relationship between different markers of glomerular function. We measured serum creatinine, DPTA, and creatinine clearances, and urinary albumin excretion. The clinical course of 24 patients (83%) permitted repeat studies over a period of 32 +/- 1 (SEM) months, and in these patients DTPA clearance, creatinine clearance, and the serum creatinine concentration did not vary with time. Five of the patients (17%) lost their grafts and returned to dialysis. On initial evaluation patients who lost their grafts had a lower DPTA clearance than those whose function was maintained (29 +/- 3 v 46 +/- 2 mL/min/1.73 m2 body surface area [BSA], respectively, P less than 0.005) and all of them had a DTPA clearance of less than 40 mL/min/1.73 m2 BSA. There was an inverse correlation between the log of the urinary albumin excretion and the DTPA clearance (n = 33, r = -0.59, P less than 0.001), a direct correlation with the serum creatinine concentration (N = 33, r = 0.89, P less than 0.0001), but no correlation with time after transplantation. Thus, despite the continued use of CsA, renal function over time was stable in patients who underwent repeated studies, as was the relationship between the DTPA clearance and the clinically used markers of transplant function, the serum creatinine concentration, and the creatinine clearance.     

Impact of long-term immunosuppression with cyclosporin A on serum lipids in stable renal transplant recipients

To determine the impact of long-term immunosuppression on serum lipids in stable renal graft recipients we measured serum lipids and apolipoprotein B concentrations in 20 patients receiving therapy with cyclosporin (CsA) and low-dose prednisolone (CsA/P) and in 18 patients on therapy with azathioprine and maintenance steroids (Aza/P). The patients were matched for age, body mass index, primary renal disease and dose of prednisolone, but not for the duration in transplantation and serum creatinine concentration. Triglyceride concentrations were significantly higher in the CsA/P group than in Aza/P-treated patients: 2.62±0.35 vs 1.62±0.23 mmol/l (P<0.05). Similarly, total cholesterol (C) levels were significantly more elevated in the CsA/P recipients than in the other group: 7.44±0.32 vs 5.84±0.25 (P<0.02). CsA/P patients had higher serum levels of LDL-C (4.79±0.20 vs 3.43±0.19 mmol/l P<0.001) and apolipoprotein B concentrations (191±13 vs 128±9 mg/dl; P<0.001). CsA/P and Aza/P recipients had similar concentrations of HDL-C (1.73±0.13 vs 1.52±0.09 mmol/l; NS). We conclude that in stable renal graft recipients with good transplant function long-term immunosuppression with CsA/P is associated with a more atherogenic lipid status than therapy with Aza/P.     

Effect of cyclosporine on the renal tubular amino acid handling after kidney transplantation

The renal tubular handling of free amino acids was studied 5-6 weeks after successful renal transplantation (tx) in 20 children treated with CsA and in 10 children treated with azathioprine (Aza). The results were compared with those of 34 control children. The amino-acid clearance studies were performed in combination with short-term inulin clearance. The CsA group revealed a mean inulin clearance of 49 +/- 16.8 ml/min/1.73 m2, the Aza group of 76.9 +/- 18.2, and the controls of 114 +/- 15.6. The plasma amino-acid concentrations were not different between CsA- and Aza-treated groups; however, most of the essential amino acids were lower in transplanted children than in controls. The decrease was correlated with the GFR. The amino-acid-clearance rates were statistically not different between both transplanted groups, but lower values than in controls were found for alanine, glycine, histidine, lysine, and phenylalanine, and significantly higher values for methionine. The fractional clearance rates of most amino acids were significantly elevated in transplanted children compared to controls. In CsA-treated patients, the fractional clearance rates of arginine, glycine, and serine were higher than in Aza-treated patients. No influence of CsA blood levels or rejection episodes on the amino-acid handling were detectable. We conclude that CsA has no specific influence on the renal handling of amino acids. Most disturbances observed depend on the graft function or may be caused by injuries to the graft following the tx procedure.     

The impact of azathioprine and cyclosporine on long-term function in kidney transplantation

To assess the impact of cyclosporine on long-term kidney function in transplant patients, we retrospectively analyzed 273 patients on azathioprine and 308 on CsA with graft functioning at 1 year. To balance the length of follow-ups, the observation of patients was cut at 5 years. Actual graft survival rate at 5 years was similar in Aza and CsA (88% vs. 90%). Multivariate analysis in Aza pts showed that proteinuria (P = 0.006) and hypertension at 1 year (P = 0.002) increased the probability of irreversible graft failure by 2.47 and 2.85, respectively. In CsA patients, proteinuria (P = 0.007) and plasma creatinine higher than 2.5 mg/dl (P = 0.006) increased the probability of graft failure by 5.12 and 6.48, respectively. In both Aza and CsA patients with a follow-up of at least 5 years, plasma creatinine levels were significantly worse at 5 years vs. 1 year (P = 0.004). The slopes of plasma creatinine values plotted vs time were not different between the two groups. Chronic graft dysfunction (CGD) was defined as a stable increase of plasma creatinine of at least 50% above stable values at 1 year. The probability of remaining without CGD at 5 years was 75% for CsA and 80% for Aza patients (P = N.S.). Multivariate analysis of factors influencing the development of CGD showed that hypertension (P = 0.003) and proteinuria at 1 year (P = 0.081) increased the probability of developing CGD by 2.19 and 1.76, respectively, in Aza, while in CsA patients proteinuria only (P = 0.063) increased the probability of developing CGD by 2.29. Graft survival at 5 years after development of CGD was 34% in Aza and 53% in CsA-treated patients. These data confirm that in the long-term CsA does not cause a higher prevalence of CGD and show that, in the presence of CGD, CsA has a superior protective effect than Aza.     

Factors affecting renal allograft function in long-term recipients.

The natural history of renal allograft function in long-term recipients is not known. To characterize renal allograft function and the factors that affect it, we reviewed the records of all patients who received a renal allograft at the University of Wisconsin between 1965 and 1981 and selected those who had annual data on renal function for at least 10 years. We identified 155 patients--78 with living-related donors and 77 with cadaveric donors. All patients were adults receiving azathioprine and prednisone. Renal function was estimated by calculated creatinine clearances (Ccr), which correlated well with measured 24-hour creatinine clearances. The creatinine clearance data for each patient were plotted versus time. In 73% of patients, the creatinine clearance increased for several years before reaching a peak value. After the peak, the creatinine clearance declined in a linear manner. Stepwise regression analyses indicated that allografts from cadaveric donors had a greater increase in creatinine clearance from the value at year 1 to the peak than allografts from living-related donors (0.35 +/- 0.25 v 0.21 +/- 0.23 mL/s [21.4 +/- 15.0 v 12.7 +/- 13.8 mL/min]; P less than 0.001). The average time to reach the peak value of creatinine clearance was longer in cadaveric allografts (6.8 +/- 3.5 v 4.6 +/- 4.0 years; P less than 0.001). Postpeak, the rate of decline in creatinine clearance was faster in cadaveric allografts than in living-related ones (0.06 +/- 0.05 v 0.04 +/- 0.04 mL/s/yr [3.50 +/- 2.99 v 2.55 +/- 2.16 mL/min/yr]; P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

High-and Low-dose Regimens of Cyclosporin in Renal Transplantation: Immunosuppressive Efficacy and Side-effects

The immunosuppressive effectiveness and nephrotoxic side-effectsof either high-dose cyclosporin (CsA) (16 mg/kg per day) orlow-dose (9mg/kg per day) in combination with azathioprine (Aza)(1 mg/kg per day) were studied in 80 renal transplant patientswho also received low-dose corticosteroids. At 3 months, patientswho received high-dose CsA were randomly assigned to eithercontinuation of CsA or conversion to Aza, whereas in the triple-therapygroup either CsA or Aza was discontinued. No differences inpatient (97.5%) or graft survival (90%–92.5%) were foundat 1 year. There were no differences in the incidence of primarynon-functioning kidneys. The incidence of acute rejection episodeswas 45% in the high-dose CsA group and 55% in the group treatedwith low CsA doses together with Aza (not significant). At 3months the mean creatinine clearance was 60±4ml/min (mean±SEM)in the high-dose group (mean cumulative CsA dose 0.96 g/kg)compared with 55±3 ml/min in the low-dose group (meancumulative CsA dose 0.60 g/kg). At 1 year no differences inthe degree of proteinuria or the incidence of hypertension wasfound between the different groups. The best mean creatinineclearance at 1 year (77±5 ml/min) was found in patientswho received high doses of CsA for 3 months followed by conversion.