Early, abrupt conversion of de novo renal transplant patients from cyclosporine to everolimus: results of a pilot study.

In a single-center study, 20 kidney transplant patients without prior rejection were abruptly converted from cyclosporine to everolimus at seven wk post-transplant. All patients received basiliximab induction with maintenance enteric-coated mycophenolate sodium and corticosteroids. Biopsy-proven acute rejection had occurred in three of 20 patients (15.0%) by the end of week seven post-conversion. All episodes were mild and reversible, with subsequent recovery of renal function. Calculated glomerular filtration rate (GFR) improved significantly (51 +/- 11 mL/min at time of conversion, 58 +/- 12 mL/min at week seven post-conversion, 57 +/- 17 mL/min at month six post-conversion; p = 0.001). No patient developed proteinuria in the nephrotic range. Twenty-two adverse events were reported in 10 patients, three of which had a suspected relationship to everolimus. Mean leukocyte and platelet count decreased significantly, and triglyceride level increased. This study suggests that kidney transplant patients without prior rejection can be converted abruptly from cyclosporine to everolimus at seven wk post-transplant, resulting in significantly improved renal function with no apparent increase, in risk of rejection and good tolerability.

Calcineurin inhibitor-free immunosuppression in renal allograft recipients with thrombotic microangiopathy/hemolytic uremic syndrome.

Thrombotic microangiopathy (TMA) and hemolytic uremic syndrome (HUS) represent serious threats to kidney allograft recipients. During a 4-year period, among 850 kidney transplantations, seven recipients with primary HUS and seven recipients (eight transplants) with previous or de novo TMA/HUS were identified and given calcineurin inhibitor (CNI)-free immunosuppression by sirolimus (SRL), mycophenolate mofetil and steroids. Thirteen out of 15 transplantations were successful in the long term; resulting in a mean creatinine of 101 mumol/L (16.4 months follow-up). In patients maintained on CNI-free regimen, no TMA/HUS recurrences were observed. A high rate of acute rejections (53%) may indicate insufficient immunosuppressive power and/or a causative relationship between TMA/HUS and rejection. Wound-related complications were abundant (60%), and call for surgical/immunosuppressive countermeasures. Our experience supports the idea that CNI's are major offenders in TMA/HUS induction. Total CNI elimination seems essential, as the nephrotoxic combination CNI + SRL may promote TMA. Features of TMA/HUS should be carefully explored in recurrent 'high responders'.

Selected activities in Scandiatransplant.

Scandiatransplant is the Nordic organ exchange organization. It has existed for 35 years and it is owned by all organ transplantation hospital departments in the five Nordic countries--Denmark, Finland, Iceland, Norway, and Sweden. The use of living organ donors for kidney transplantation has become a more common procedure not only in Norway but also in Sweden and Denmark. For the first time, in 2003, one transplant center performed relatively more living donor kidney transplantations than with deceased donors. The overall organ transplant activity reveals a remarkably stable situation in the area covered by Scandiatransplant. Scandiatransplant as an organ exchange organization has changed from a solely kidney exchange organization to an organization in which the more immediate vital organs as liver and heart are exchanged more commonly than kidneys.

Should kidneys from older cadaveric donors be age-matched to the recipient?

Persistent shortage of kidneys for transplantation has forced most transplant centers to include procurement and use of kidneys from older donors. It is not clear whether the optimal use of these kidneys involve age-matching to the recipient. The aim of this study was to evaluate the clinical outcome of older cadaveric kidneys (>60 years), transplanted to young recipients (<50 years) and older recipients (>60 years). From 1989 through 2002, 252 first kidney grafts were procured from donors above the age of 60; 149 of the recipients to these grafts were above 60 years and 45 recipients were below 50. Minimum follow-up time was 12 months. Variables for waiting time to transplantation, DR mismatches, PRA, dialysis prior to transplantation, episodes of acute rejection, number of steroid-resistant rejections, creatinine levels, cold ischemia time, and causes of graft loss did not differ between the two groups. There was no significant difference in graft survival for young and older recipients receiving kidney from donors above 60 years of age. Graft survival at 1 year for young recipients was 90% and for older recipients 93% (NS). Five-year graft survival was 72% and 79%, respectively (NS). However, there was a significant positive effect on long-term graft survival if the donor kidney was less than 50 years. From our data, there is no evidence that age-matching of older donors has any beneficial effect on graft survival in kidney transplantation.

MicroCRP: a highly sensitive CRP method applied in the monitoring of renal allograft recipients.

A new ultrasensitive fluoroimmunometric assay for C-reactive protein (CRP), called MicroCRP assay, has a lower detection limit of 0.05 mg/l, and a CV of 7.6% at concentration 0.25 mg/l. The microCRP levels in healthy adults show a skewed distribution, median 0.90 mg/l and mean 1.4 mg/l, with 2.5th and 97.5th percentiles of 0.17 and 4.7 mg/l, respectively, and no gender-related or age differences. Serial microCRP was applied in the monitoring of 37 renal allograft recipients. The operative trauma gave rise to an initial CRP peak, usually on day 2 after transplantation, with a return to preoperative value 1 week after surgery. There were significant CRP elevations (>25%) in all cases of rejections, indicating 100% sensitivity. The microCRP values started to increase about 3 days (range -1 to 9 days) before the rise in creatinine. The microCRP peak tended to be higher in rejection episodes with a vascular component, compared with episodes of cellular rejection (p=0.05). A rise in microCRP at days 7-12 after transplantation seems to predict the risk of rejections later on, and probably reflects the primary immune response to the graft. Recipients without this primary CRP response (only 6 of 37 patients) subsequently had uncomplicated courses. Tracking of values below the traditional lower limit is essential in order to recognize the different CRP peaks. Serial monitoring of microCRP is well suited for clinical use and provides clinical information previously unattainable with other assay systems.

[Immunosuppressive agents in organ transplantation]. / Immunsuppressive medikamenter ved organtransplantasjon.

Initial use of intensive immunosuppressive therapy is mandatory after organ transplantation; during the following months treatment is tapered to the lowest effective and tolerable maintenance level. Immunosuppressants with different mechanisms of action are combined in order to obtain additive or synergistic effects, and to reduce the incidence of adverse effects. Traditional immunosuppressive agents like azathioprine, steroids, cyclosporine and polyclonal and monoclonal antibodies against T-cell antigens are challenged by new drugs like mycophenolate mofetil, tacrolimus, sirolimus and interleukin-2 receptor monoclonal antibodies. A combination of the most potent drugs could induce nearly complete immunosuppression. Such treatment, however, is a delicate balance between rejection due to poor immunosuppression on one side and, on the other, infections and malignancies induced by overtreatment. According to current protocols, therapeutic drug monitoring is used to individualize the dosage of immunosuppressants and as a means to control the tapering of these drugs. Validation of new immunosuppressive agents should be based on data from long-term studies including patient survival and graft function and survival as endpoints. Among the most recent achievements, inhibitors of costimulatory signaling in T-cells are of clinical interest since they may induce donorspecific tolerance and thereby alleviate the need for life-long maintenance immunosuppressive therapy.

Living donor kidney transplants: a biopsy study 1 year after transplantation, compared with baseline changes and correlation to kidney function at 1 and 3 years.

INTRODUCTION: Chronic changes in biopsies from long-term stable kidney allografts have been reported to correlate with graft prognosis. Morphological changes in baseline ('zero-hour') biopsies have been described as well, but their importance for long-term prognosis have been less clear. The aim of the present study was to evaluate biopsy changes from baseline to 1 year after transplantation in patients receiving kidneys from living donors, and to assess the possible prognostic implications of these findings. METHODS: Light microscopical changes in 18 gauge full-core biopsies were scored semi-quantitatively in 33 patients 1 year after transplantation, and compared to baseline changes previously reported [1]. All cases were also examined with transmission electron microscopy. The semi-quantitative data from baseline and at 1 year were correlated with kidney function 1 and 3 years after transplantation. The reproducibility of baseline findings regarding arteriosclerosis and arteriolar hyalinosis was tested by comparison with biopsies 1 week after transplantation (n = 43). RESULTS: We found a significant increase in mesangial glomerular sclerosis (P<0.001), interstitial fibrosis/tubular atrophy (if/ta) (P = 0.002), and mononuclear cell interstitial infiltration (P = 0.003) after 1 year, compared to baseline changes. There was an increase of arteriosclerosis (P = 0.028) and arteriolar hyalinosis (P = 0.006) when compared to biopsies taken 1 week after transplantation, but not when compared to the 'zero-hour' findings. Electron microscopy revealed one case of recurrent immune-complex glomerulonephritis and another case of recurrent light chain deposition kidney disease. Comparing 1-week vascular findings with baseline gave a low level of reproducibility, probably due to sampling error. Baseline biopsy findings could not predict long-term kidney function. In the 1-year biopsy, if/ta was significantly correlated with serum creatinine (P = 0.007) and glomerular filtration rate (GFR) (P<0.001) at 1 year, with serum creatinine at 3 years (P = 0.011), and with the first-year cumulative dose of methylprednisolone (P = 0.004). Serum creatinine at 1 year, however, was found to be the most accurate predictor of 3-year kidney function (P<0.001). Donor age was correlated to kidney function at 3 years (P = 0.013) but not at 1 year after transplantation. CONCLUSION: Morphological changes in baseline biopsies of living donor kidneys tend to become more pronounced in well-functioning allografts during the first year after transplantation. In the 1 year biopsy, if/ta seems to be the most reliable variate for grading of chronic changes. However, 1-year serum creatinine predicted long-term kidney function more precisely than did the biopsy scores. Based on the results of the present study, a protocol 1-year biopsy does not seem warranted in the management of the graft recipient with a stable kidney function.

Immediate and early renal function after living donor transplantation.

BACKGROUND: In order to assess the immediate renal function after living donor transplantation, renal function was compared in eight renal allograft recipients and their living related kidney donors during the first 24 h after transplantation. METHODS: Substantial and comparable intraoperative volume loading with Ringer's acetate and mannitol was performed together with the administration of frusemide. Glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were estimated by the clearances of inulin and p-aminohippurane, respectively. Tubular reabsorptive function and injury were estimated from the clearance of lithium, the fractional excretion of sodium and the urinary excretion of N-acetyl-beta-glucosaminidase. RESULTS: One hour after completion of surgery, GFR (54 +/- 7 ml/min) and ERPF (294 +/- 35 ml/min) were only 30% lower in the grafts than in the remaining donor kidneys, increasing to similar levels within 3 h. Only minor tubular dysfunction and injury were revealed in the grafted kidneys, and these tended to normalize within 24 h. CONCLUSIONS: By the present transplantation procedure comprising short ischaemia time and substantial volume expansion combined with mannitol and frusemide administration, kidneys from living donors regain nearly normal function within a few hours after transplantation.

A randomized multicenter trial of the anti-ICAM-1 monoclonal antibody (enlimomab) for the prevention of acute rejection and delayed onset of graft function in cadaveric renal transplantation: a report of the European Anti-ICAM-1 Renal Transplant Study Group.

BACKGROUND: T-cell activation through T-cell receptor engagement requires co-stimulatory molecules and also adhesion molecules such as ICAM-1. Moreover ICAM-1 mediates leukocyte invasion from the blood into tissue during inflammatory processes. In animal studies using mouse monoclonal antibodies against ICAM-1 (enlimomab), renal allograft survival has been improved and reperfusion damage from ischemia reduced. The European Anti-ICAM-1 Renal Transplant Study (EARTS) was a randomized, double-blind, parallel-group, placebo-controlled study lastingl year and performed in 10 transplant centers in Europe. METHODS: A total of 262 recipients of cadaveric kidneys were given either enlimomab or a placebo for 6 days and were given triple immunosuppressive therapy of cyclosporine, azathioprine, and prednisolone. The primary efficacy endpoint was the incidence of the first acute rejection within 3 months, and each event was assessed by a committee including investigators and independent pathologists. RESULTS: There was no significant difference in the incidences of first acute rejection at 3 months between the placebo and enlimomab groups (39% vs. 45%), and enlimomab did not reduce the risk of delayed onset of graft function (DGF) (26% vs. 31%). Neither was there a difference in patient survival (95% vs. 91%) or graft survival (89% vs. 84%) at 1 year. Fatal events occurred in 19 (7%) patients (7 placebo, 12 enlimomab). Clinically, the most important non-fatal adverse events were infections; however, there was no statistically significant difference between the incidences in the two groups (70% vs. 79%). CONCLUSION: Short term enlimomab induction therapy after renal transplantation did not reduce the rate of acute rejection or DGF.

Monitored high-dose azathioprine treatment reduces acute rejection episodes after renal transplantation.

BACKGROUND: Azathioprine (AZA) is widely used in organ transplantation. Common practice is to adjust dose according to body weight only, despite documented pharmacokinetic variability. The purpose of this study was to investigate whether high-dose AZA treatment monitored by 6-thioguanine nucleotides (6-TGN) levels reduces the incidence of rejection episodes in renal transplantation without a corresponding increase in myelotoxicity. METHODS: Patients receiving cyclosporine, steroids, and AZA were randomized into either the low-dose AZA group (3 mg/kg on day 0, then 2 mg/kg/day the first week and 1 mg/kg/day thereafter) or the high-dose AZA group. In the latter, AZA was started at 5 mg/kg/day and then adjusted to keep 6-TGN concentrations (measured twice weekly) between 100 and 200 pmol/8 x 10(8) RBCs. RESULTS: A total of 360 transplant recipients were included in the final analysis. The cumulative incidence of first rejection episodes was reduced by 21%, from 62.8% in the low-dose group to 49.4% in the high-dose group (difference: 13.3%; 95% confidence interval: 3.2-23.5). Similar results were found in subgroups according to HLA-DR match. The 6-TGN concentration was significantly higher in the high-dose AZA group during the first month, and the reduction in rejection episodes was achieved in the same period. A larger proportion of patients in the high-dose group had nadir white blood cell count below 2.0 x 10(9) leukocytes/L (13.3% vs. 4.4%; difference: 8.9%; confidence interval: 3.1-14.7). CONCLUSIONS: High-dose AZA therapy in a triple-drug regimen, monitored by 6-TGN, will keep myelotoxicity within acceptable limits with the benefit of a reduction in acute rejection episodes.

Unrelated living donors in 141 kidney transplantations: a one-center study.

BACKGROUND: Kidney transplantation is the optimal treatment for the majority of patients with end-stage renal disease. However, the shortage of kidneys for transplantation is a global problem, and any attempt to improve the donor situation would be of benefit to the growing number of patients on transplant waiting lists. PATIENTS AND METHODS: Since 1984, we have transplanted 141 kidneys from genetically unrelated living donors. Donors were most often spouses and were accepted regardless of HLA match grade. Preemptive transplantation was performed in 39% of the patients. Standard triple-drug immunosuppression with prednisolone, cyclosporine, and azathioprine was used. The patients were followed from 6 months to 13 years. RESULTS: The incidence of acute rejection during the first 3 months after transplantation was higher in recipients of grafts from unrelated donors than in recipients of grafts from related living donors or cadaveric donors. However, unrelated living donor grafts survived significantly better than did cadaveric grafts (P < 0.02) and had a survival rate similar to that of living-related donor grafts mismatched for one or both HLA haplotypes. The perioperative complication rate for the donor was low. CONCLUSION: We consider unrelated living donors an excellent source for alleviating the shortage of donor kidneys.

Morphological studies of baseline needle biopsies from living donor kidneys: light microscopic, immunohistochemical and ultrastructural findings.

Fifty-seven consecutive living donors (31 women and 26 men aged 20.7-72.3 years, mean 50.6 years) were subjected to needle biopsy during nephrectomy, immediately before removal of the kidney. By light microscopy, semiquantitative scoring (0-3) was performed for arteriosclerosis, arteriolar hyalinosis (hyalin arteriolosclerosis), glomerulosclerosis, interstitial mononuclear cell infiltration, and interstitial fibrosis/tubular atrophy. Whereas vascular changes were striking in many biopsies (arteriosclerosis grades 2-3: 28/54 cases, arteriolar hyalinosis grades 2-3: 15/55 cases), glomerular and tubulointerstitial changes were mostly low grade. The morphological changes tended to be more pronounced in middle-aged and older individuals, but, in particular, vascular changes were seen also in the younger age group. Immunofluorescence microscopy revealed glomerular granular staining for IgM in 52.7% of the cases, IgA in 9.1%), IgG in 1.8%, and C3 in 12.7%. The main ultrastructural finding was glomerulosclerosis; one case with diffuse glomerular IgA showed distinct dense deposits, and one case showed similar dense deposits without IgA deposition. Arteriolar wall deposition of C3 was found in 58.2% of the cases, and IgM in 10.9%. Especially C3 occurred both with arteriolar hyalinosis and in arterioles without light microscopic alterations. The observation of significant vascular changes in baseline biopsies is relevant especially in the differential diagnosis of chronic rejection and cyclosporine nephropathy. The immunohistochemical findings strongly indicate the occurrence of immunoglobulins and complement factor C3 in both glomeruli and arterioles without clinical or morphological signs of renal disease. The possible pathophysiological significance of such deposits remains, however, uncertain.

The national kidney transplant program in Norway still results in unchanged waiting lists.

1. Of 2,670 patients starting renal replacement therapy for end-stage renal disease in Norway from 1989-1997, 76% were candidates for transplantation. The annual need for transplantations increased from 47 to 64 grafts PMP as the number of elderly patients increased. The national waiting list has remained almost stable during the period from 1989-1997 at levels of 25-30 PMP, but the dialysis population has increased from 57-105 PMP. 2. A total of 1,681 transplants was performed at an annual rate varying between 38 and 46 grafts PMP. The grafts were procured from LDs in 41% and CDs in 59% of cases. Totally 69% of all patients in need were transplanted and 54% of all patients requiring replacement therapy for end-stage renal disease received a transplant. 3. Graft survival rates in recipients of first LD grafts (n = 641) were 91% and 77% at one and 5 years, respectively. One-year graft survival was 97% in HLA-identical grafts (n = 71), 92% in haploidentical grafts (n = 419), 88% in 2 haplotype-mismatched related grafts (n = 43), and 87% in spousal donor grafts (n = 108). 4. Graft survival rates in recipients of first CD grafts (n = 801) were 84% and 65% at one and 5 years, respectively. The rates were 86% and 74% in younger (n = 557) versus 78% and 46% in older (> 65 years) (n = 244) patients. Death with a functioning graft caused approximately 45% and 75% of all graft losses in younger and older patients, respectively. Cardiovascular disease was the major cause of death. 5. A significant beneficial effect of HLA-DR matching was observed in CD grafts performed after 1989, in particular in patients older than age 65.

Patterns of azathioprine metabolites in neutrophils, lymphocytes, reticulocytes, and erythrocytes: relevance to toxicity and monitoring in recipients of renal allografts.

Monitoring of azathioprine (AZA) therapy by the measurement of 6-thioguanine nucleotides (6-TGN) concentrations in red blood cells (RBC) may improve safety and ensure optimal immunosuppressive effects of AZA in organ transplantation. The authors explored the rationale for such monitoring by measuring thiopurine metabolites in peripheral blood cell types that are more relevant to the effects and kinetics of AZA and its active metabolites. Neutrophil granulocytes were isolated by density gradient centrifugation, and CD4+ lymphocytes and reticulocytes by using specific immunomagnetic beads. In neutrophils, 6-TGN concentrations had median measurements 31 times higher than in RBCs. In contrast to the high methylated mercaptopurine (me-MP) concentrations in RBCs, these metabolites were not detected in the neutrophils. Thiopurine metabolite levels were lower than the analytic limit of detection in all the CD4+ samples. The concentrations of 6-TGN and me-MPs were lower in reticulocytes than in RBCs in general, indicating that thiopurine metabolites are taken up by RBCs in the circulation. This study's findings, that 6-TGN concentrations are very high in neutrophils, whereas me-MPs are undetectable, many explain the specific neutropenic adverse effect of AZA. The results also add support to monitoring AZA through measurements of 6-TGN and me-MPs in RBCs.

Possibilities for therapeutic drug monitoring of azathioprine: 6-thioguanine nucleotide concentrations and thiopurine methyltransferase activity in red blood cells.

The objectives of this study were to establish monitoring of azathioprine (AZA) treatment in renal allograft recipients by red blood cell (RBC) 6-thioguanine nucleotide (6-TGN) measurements and to characterize the variability of RBC thiopurine methyltransferase (TPMT) activity and the effects on 6-TGN levels and the incidence of rejection episodes. In 82 renal allograft recipients, the effect of standard AZA dosage (3 mg/kg tapered to 1 mg/kg) was compared with higher dosages (3 mg/kg for several days) under 6-TGN monitoring. The authors measured TPMT in these patients and in a group not receiving AZA. The authors did not find an inverse correlation between RBC TPMT activity and 6-TGN concentrations, and baseline TPMT activity did not predict the incidence of rejection episodes The slight increase in RBC TPMT activity after transplant was associated with the use of furosemide rather than AZA; in the five patients receiving furosemide for less than 10 days, TPMT activity declined. The higher AZA dosage in the 6-TGN monitored group was not sufficient to increase RBC 6-TGN to target levels (100 to 200 pmol/8 x 10(8) RBC); median 6-TGN levels were similar in the two groups, as was the incidence of rejection episodes. Based on these findings, the authors suggest that higher dosages be studied in conjunction with 6-TGN monitoring, to explore the possibilities for therapeutic improvements.

Serum amyloid A protein is a clinically useful indicator of acute renal allograft rejection.

BACKGROUND: Early diagnosis of acute rejection after renal transplantation is important. There is evidence that measurement of the acute phase proteins, C-reactive protein (CRP) and serum amyloid A protein (SAA) is helpful. METHODS: In 64 consecutive patients, CRP was measured in a routine clinical system (Technicon RA1000, Bayer) and SAA in a new sensitive automated immunoassay on the Abbott IMx instrument, daily or on alternate days for 30 days after renal transplantation. RESULTS: Patients all received triple immunosuppression with cyclosporin, azathioprine, and prednisolone and all mounted a post-surgical acute phase response of SAA, but the CRP response was reduced or absent. Serum creatinine rose significantly in 36 patients, leading to treatment for first rejection. Thirty of these episodes were confirmed rejection, three were definitely not and three were uncertain. SAA. normally < 10 mg/l, rose to more than 100 mg/l in all episodes except when rejection was definitely absent. In six cases SAA rose above 100 mg/l 1-3 days before the rise in creatinine leading to antirejection therapy, and only twice did creatinine rise 1 day before SAA. In contrast, CRP responses to rejection were modest or absent. In four patients there were SAA and CRP responses unrelated to rejection, three associated with intercurrent infection and one with administration of antilymphocyte globulin. There were also two unexplained isolated spikes of SAA. CONCLUSIONS: SAA is a sensitive marker of acute renal allograft rejection. It is not specific, but the differential behaviour of CRP in patients receiving cyclosporin helps to distinguish infection from rejection. Availability of rapid assays for these analytes should facilitate management of renal allograft recipients.