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T Leivestad

Publications and source records attributed to T Leivestad.

At least 19 recordsLinked to original sources

The impact of early-diagnosed new-onset post-transplantation diabetes mellitus on survival and major cardiac events.

The impact of early-diagnosed new-onset post-transplantation diabetes mellitus (PTDM) on cardiovascular (CV) disease is not well described. The objectives of the present prospective single-center observational study were to assess the long-term effects of early-diagnosed new-onset PTDM on major cardiac events (MCE; cardiac death or nonfatal acute myocardial infarction) and patient survival. Diabetic status and CV risk factors were assessed in 201 consecutive renal allograft recipients 3 months after transplantation (baseline) during a period of 16 months (1995-96). Follow-up data until January 1, 2004 were obtained from the Norwegian Renal Registry. The 8-year (range 7-9 years) cumulative incidence of MCEs was 7% (nine out of 138) in recipients without diabetes, 20% (seven out of 35) in patients with new-onset PTDM and 21% (six out of 28) in patients with diabetes mellitus before transplantation (DM). Proportional hazards regression analyses (forward stepwise regression) revealed that patients with PTDM had an approximately three-fold increased risk of MCEs as compared with nondiabetic patients (hazard ratio (HR)=3.27, 95% confidence interval (CI)=1.22-8.80, P=0.019). A total of 61 patients (30%) died. Eight-year patient survival was 80% in the nondiabetic group, 63% in the PTDM group and 29% in the DM group, respectively. Pretransplant diabetes (HR=5.09, 95% CI=2.60-9.96, P<0.001), age (HR=1.03, 95% CI=1.01-1.05, P=0.016), cytomegalovirus (CMV) infection (HR=2.66, 95% CI=1.27-5.53, P=0.009), and creatinine clearance (HR=0.98, 95% CI=0.96-1.00, P=0.046), but not PTDM (HR=1.20, 95% CI=0.58-2.49, P=0.621), were independent predictors of death in the multiple Cox regression model. Early-diagnosed PTDM is a predictor of MCEs, but not of all-cause mortality, the first 8 years after renal transplantation.

Adult↗

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.

Adult↗

Experience with cyclosporine in 1519 kidney transplantations from living donors in a national transplant programme, 1983-2002.

Following the introduction of cyclosporine as basic immunosuppression in our national transplant programme in 1983, the pool of grafts from living donors (LDs) was expanded 2 years later by also accepting LDs mismatched for 2 HLA haplotypes and living unrelated donors (LURDs), mostly spouses. A policy of approaching family members to promote donation was consistently pursued. During 1983 through 2002, nephrectomy was performed on 1519 LDs without mortality. From 1983 through 1988, our learning phase in managing cyclosporine-immunosuppression, 382 patients received first grafts from LDs. One-year graft survival (GS) rates were 94.4%, 90%, 89%, and 82% in 71 HLA identical, 260 haploidentical, 18 2-haplotypes disparate, and 33 LURD graft recipients, respectively. Corresponding half-lives were 15.8, 10.3, 11, and 9.1 years, respectively. Results improved in 1028 patients receiving first LD grafts from 1989 through 2002. Corresponding 1-year GS rates were 96.6% (n=117), 93.5% (n=650), 90.4% (n=73), and 88.8% (n=188), and half-lives were 30, 13.3, 13.5, and 12.3 years, respectively. Similar GS rates were observed in 109 recipients of repeat grafts from LDs. LDs contributed 44% and 21.6% of all first and repeat grafts transplanted, providing grafts to 11 patients (in 1983) increasing to 23 patients (in 2002) per million population per year (pmp/y). When added to grafts from cadaveric donors, 40 to 48 pmp/y were provided with a first or repeat graft since 1990, thus covering at least 65% of the national need for kidney transplantations.

Cyclosporine↗

Role of HLA molecules in the induction of alloimmune responses: clinical significance in the cyclosporine era.

HLA molecules are peptide-presenting molecules for T cells. T-cell receptors (TCR) recognize antigen-derived peptides bound to HLA molecules in cell membranes, namely, peptide-HLA (pHLA) complexes. An allograft will be recognized as foreign by recipient T cells via two slightly different mechanisms--direct and indirect allorecognition. In direct allorecognition, recipient T cells directly recognize foreign pHLA complexes on donor cells, in particular on donor dendritic cells (DC). In indirect allorecognition, recipient T cells recognize foreign peptides from the graft presented by self-HLA molecules on recipient DC. Cyclosporine (CsA) inhibits some activation signals in T cells as the result of allorecognition. Notwithstanding the strong immunosuppressive effects of CsA, reducing the degree of allorecognition through HLA matching is still of clinical significance. Data from our own transplant center and results from others demonstrate that the introduction of CsA as a main immunosuppressive drug does not nullify the significant beneficial effects of HLA matching on the frequency and strength of rejection episodes as well as on graft survival after allotransplantation. In cadaveric donor transplantation we observe significant effects of matching just for a limited number of (broad) HLA-DR molecules. We conclude that one should take advantage both of the strong immunosuppressive effects of CsA and other modern immunosuppressants as well as the beneficial effects of optimal HLA matching in clinical transplantation.

Cyclosporine↗

Diabetic nephropathy and end-stage renal failure: the Norwegian story.

Diabetic nephropathy is the most common single cause of end-stage renal failure (ESRF) in the Western world, recorded as the cause of renal failure in up to 40% to 45% of those entering renal replacement therapy (RRT) programs. However, marked differences exist between countries; the percentage of patients entering RRT in Norway because of diabetic nephropathy is 10% of the incident RRT population. The percentage in the United States is approximately 40%; therefore, the purpose of the present study was to compare data from Norway with data from the United States in an attempt to detect factors that might explain some of the differences. To make the comparisons as valid as possible, an attempt has been made to focus on populations of similar genetic make-up. The incidence of type 1 diabetes is a little higher in Norway than in the United States, whereas the prevalence of type 2 diabetes may be twice as high in the United States as in Norway; marked differences in the prevalence of obesity is probably a significant causative factor. There seems to be no striking difference in the prevalence of microalbuminuria in people with diabetes in the two populations, whereas there are insufficient data to compare the prevalence of overt proteinuria. The incidence of patients with a diagnosis of diabetic nephropathy as the cause of ESRF entering RRT in the two study populations showed marked differences; the incidence for 1997 was 8.9/million population in Norway and 113/million population in the United States. The proportion of type 2 diabetes was 46% in Norway and 64% in the US (1997). It is unlikely that the marked difference in incidence of RRT can be explained by differences in type 2 diabetes prevalence alone. The populations may not be directly comparable, and differences in the size of study populations and in the choice of renal diagnosis in patients with diabetes as a comorbid factor at the beginning of RRT may introduce uncertainties. Further, data on other factors--such as incidence of death before RRT is indicated, quality of care, and health care delivery, expressed as degree of blood pressure and metabolic control--were not available. Differences in acceptance of diabetes patients into RRT programs are not believed to contribute significantly. Norway is seeing a development toward increasing body weight and a change toward a more sedentary lifestyle, together with an increasing prevalence of type 2 diabetes earlier in life than has previously been the case. An increase in diabetic nephropathy and need for RRT because of type 2 diabetes must therefore be expected in Norway. To understand differences and to best design preventive programs, further comparative studies of the two populations seem warranted.

Diabetes Mellitus, Type 1↗

Renal replacement therapy in Europe: the results of a collaborative effort by the ERA-EDTA registry and six national or regional registries.

BACKGROUND: In June 2000 a new ERA-EDTA Registry Office was opened in Amsterdam. This Registry will only collect core data on renal replacement therapy (RRT) through national and regional registries. This paper reports the technical and epidemiological results of a pilot study combining the data from six registries. METHODS: Data from the national renal registries of Austria, Finland, French-Belgium, The Netherlands, Norway, and Scotland were combined. Patients starting RRT between 1980 and 1999 (n=57371) were included in the analyses. Cox proportional hazards regression was used to predict survival. RESULTS: The use of different coding systems for ESRD treatment by the registries made it difficult to merge the data. Incidence and prevalence of RRT showed a continuous increase with a marked variation in rates between countries. The 2-, 5- and 10-year patient survival was 67, 35 and 11% in dialysis patients and 90, 81 and 64% after a first renal allograft. Multivariate analysis showed a slightly better survival on dialysis in the 1990-1994 (RR 0.94, 95% CI 0.90-0.98) and the 1995-1999 cohort (RR 0.88, 95% CI 0.84-0.92) compared to the 1980-1984 cohort. In contrast, there was a much greater improvement in transplant-patient survival, resulting in a 56% reduction in the risk of death within the 1995-1999 cohort (RR 0.44, 95% CI 0.39-0.50) compared to the 1980-1984 cohort. CONCLUSIONS: This study provides support for the feasibility of a "new style" ERA-EDTA registry and the collection of data is now being extended to other countries. The improvement in patient survival over the last two decades has been much greater in transplant recipients than in dialysis patients.

Austria↗

A prospective study of the natural course of cytomegalovirus infection and disease in renal allograft recipients.

BACKGROUND: Cytomegalovirus (CMV) infection is the single most frequent infectious complication in renal transplant recipients. Because no CMV-prophylaxis is given and ganciclovir is used only as deferred therapy for CMV disease at our center, we have been able to study the natural course of CMV infections. The aim was to assess risk factors for CMV infection and disease and thus identify subgroups of patients likely to benefit from CMV prophylaxis or preemptive therapy. METHODS: Between October 1994 and July 1997, 477 consecutive renal transplant recipients (397 first transplants and 80 retransplants) were included in the study. The patients were followed prospectively for 3 months with serial measurements of CMV pp65 antigen for monitoring activity of CMV infections. RESULTS: The incidence of CMV infections in first transplants was 68% in D+R- and D+/-R+ serostatus groups, whereas the incidence of CMV disease was higher in D+R- (56%) than in D+/-R+ (20%, P<0.001). No difference in severity of CMV disease in D+R- and D+/-R+ was seen except for an increased incidence of hepatitis in primary infections. One of 14 deaths could be associated with CMV disease in a seropositive recipient. Cox regression analysis showed that rejection (RR 2.5, P<0.01) and serostatus group D+R- (RR 3.9, P<0.001) were significant risk factors for development of CMV disease. The maximum CMV pp65 antigen count had significant correlation to disease only in CMV seropositive recipients, P<0.001. Conclusion. Renal transplant recipients can safely be given deferred ganciclovir therapy for CMV disease if they are intensively monitored for CMV infection. Patients with primary CMV infection (D+R-), CMV infected patients undergoing anti-rejection therapy and R+ patients with high CMV pp65 counts seem to have a particular potential for benefit from preemptive anti-CMV-therapy.

Adolescent↗

[Active uremia therapy in autosomal dominant polycystic kidney disease].

BACKGROUND: Autosomal dominant polycystic kidney disease is the most frequent inheritable kidney disease. Epidemiological studies have not been performed in Norway. MATERIAL AND METHODS: Based on the Norwegian Renal Registry, we retrospectively studied 375 patients diagnosed with this disease taken into renal replacement therapy between 1980 and 1997. They were compared with patients with glomerulonephritis. RESULTS: The average age for autosomal dominant polycystic kidney disease patients at start of renal replacement therapy was 55.2 years with a significant difference (p < 0.003) between men (53.7 years) and women (57.1 years). 295 patients (78.7%) were transplanted while 80 (21.3%) were not transplanted. From start of renal replacement therapy autosomal dominant polycystic kidney disease patients had a significantly higher (p = 0.0002) five year survival rate (70%) compared with glomerulonephritis patients (60%). One and five year patient survival rates were significantly higher (p = 0.0006) for living donor recipients (95% and 90%) compared with necro-kidney recipients (90% and 75%). One year graft survival rates for kidneys from living donors was 90% and 80% for necro-kidneys, after five years the graft survival rate was 80% and 65% (p = 0.0026). After an average of five years, 227 (60.5%) patients are alive, 197 with functioning kidney grafts (87%) while 30 (13%) are on dialysis. INTERPRETATION: Male autosomal dominant polycystic kidney disease patients start renal replacement therapy earlier than female patients. Autosomal dominant polycystic kidney disease patients do have better patient survival in renal replacement therapy than patients with glomerulonephritis.

Adult↗

Are heart transplant recipients more likely to develop skin cancer than kidney transplant recipients?

Non-melanoma skin cancer is frequent in organ transplant recipients. The risk of posttransplant cutaneous squamous cell carcinoma in Norwegian heart transplant recipients (n = 148) and kidney transplant recipients (n = 1020) on triple immunosuppressive therapy with cyclosporine, azathioprine, and prednisolone, transplanted between 1983 and 1992, were studied. After adjustment for age at transplantation in multivariable Cox models, heart transplant recipients had a significantly 2.8-times higher risk of developing squamous cell carcinoma relative to kidney transplant recipients. The risk relative to the general population (standardized incidence ratio) was higher in heart transplant recipients than in kidney transplant recipients. The results indicate that heart transplant recipients are more likely to be diagnosed with skin cancer than kidney transplant recipients, probably due to the higher doses of cyclosporine and azathioprine after heart transplantation used at our center in the study period.

Azathioprine↗

Skin cancer in kidney and heart transplant recipients and different long-term immunosuppressive therapy regimens.

BACKGROUND: Nonmelanoma skin cancer occurs frequently in organ transplant recipients, but the relative importance of different immunosuppressive therapy regimens is unclear. OBJECTIVE: We studied the risk of skin cancer in the complete, single-center Norwegian cohort of kidney and heart transplant recipients (n = 2561). METHODS: We determined cancer risk estimation by means of standardized incidence ratios and multivariate Cox regression. RESULTS: Transplant recipients had an increased risk of cutaneous squamous cell carcinoma (SCC) (65-fold), malignant melanoma (3-fold), and Kaposi's sarcoma (84-fold), and of lip SCC (20-fold), compared with the general population. After adjustment for age, kidney transplant recipients receiving cyclosporine, azathioprine, and prednisolone had a significantly (2.8 times) higher risk of cutaneous SCC relative to those receiving azathioprine and prednisolone. After adjustment for age and type of immunosuppressive regimen, heart transplant recipients had a significantly (2.9 times) higher risk than kidney transplant recipients. CONCLUSION: The risk of cutaneous SCC, malignant melanoma, Kaposi's sarcoma, and lip SCC is increased in kidney and heart transplant recipients. The risk of posttransplant cutaneous SCC is related to the degree of immunosuppression caused by long-term immunosuppressive therapy.

Adolescent↗

Preservation of renal function by percutaneous transluminal angioplasty in ischaemic renal disease.

BACKGROUND: The purpose of this study was to evaluate the effects of percutaneous transluminal renal angioplasty (PTRA) on preservation of renal function in patients with bilateral renal artery stenoses or stenosis of the artery of one functioning kidney. METHODS: A total of 227 PTRAs of 223 stenoses in 135 patients were performed from 1982 to 1993 in a single centre and retrospectively reviewed. The number of PTRAs per patient was 1.7, range 1-6. Angiographical follow-up was performed in 77%, 120+/-82 days after the first PTRA and 273+/-345 days after the last PTRA. Follow-up of serum creatinine and blood pressure was performed in 85% after 414+/-558 days. Long-term follow-up was performed for dialysis, surgical revascularization, renal transplantation and death, mean follow-up 8.8 years, range 5.5-14.8. RESULTS: The immediate technical success was 90%, and another 5% were improved. The primary patency rate per patient was 43% and the secondary patency rate 64%. Improved renal function was achieved in 23% of the patients, stabilized in 56% and failed in 21%. Stabilized or improved function was higher when baseline serum creatinine was < or =250 micromol/l (85%) than >250 micromol/l (60%). Three of 99 (3%) patients with creatinine < or =250 micromol/l started dialysis during follow-up (41 days, 7.4 and 8 years), as did 13 of 36 (36%) patients with creatinine >250 micromol/l. Blood pressure and the number of antihypertensive drugs decreased in patients with creatinine < or =250 micromol/l, but was unchanged in those with creatinine >250 micromol/l. The 5-year survival rates were 84, 66 and 17% for patients with creatinine <125 micromol/l, 125-250 micromol/l and >250 micromol/l, respectively. Twelve patients (9%) experienced complications, including two deaths. CONCLUSIONS: Our study shows that PTRA improved or preserved the renal function in most patients with normal to moderately impaired renal function. Close follow-up and possibly re-intervention are necessary to obtain satisfactory clinical and angiographical result.

Adult↗

The role of HLA matching in renal transplantation: experience from one center.

The influence of serology-based HLA matching on the risk of acute rejection episodes and of graft loss was analyzed in a material of 678 living donor (LD) and 997 cadaveric donor (CD) renal transplantations performed in our center in the period 1989-97. In LD transplantation, recipients of HLA-identical sibling grafts had the lowest rejection risk and the best graft survival, with a half-life estimate of 30 years. One-HLA-haplotype mismatched grafts did better than two-haplotype mismatched related or unrelated donor grafts. Matching for HLA-DR significantly reduced the rejection risk of one-haplotype mismatched grafts. In CD first transplants, HLA-DR matched grafts had a lower incidence of rejection and better survival than HLA-DR mismatched grafts. Expected half-life for HLA-DR matched grafts was 12 years compared to less than 7 years for HLA-DR mismatched grafts. The effects of matching for HLA-A and -B did not reach statistical significance. In CD regrafts, a two-antigen mismatch for HLA-A or -DR led to a significantly poorer graft survival, but the panel-reactive antibody (PRA) status of the recipient was the most influential factor. In CD renal transplantation, we conclude that organ allocation based on matching for HLA-DR 1-14 is effective and not too difficult to obtain even in centers with a short patient waiting list.

Adolescent↗

A strong impact of matching for a limited number of HLA-DR antigens on graft survival and rejection episodes: a single-center study of first cadaveric kidneys to nonsensitized recipients.

BACKGROUND: A single-center study of 655 nonsensitized recipients of primary cadaveric kidney grafts is presented. RESULTS: Graft survival in serologically HLA-DR 1-10 antigen-matched grafts to nonsensitized recipients at 1 year was 90%, compared with 82% (P=0.004) and 73% (P=0.001) in one and two DR antigen-mismatched grafts. The corresponding figures at 5 years were 76%, 62%, and 56%, respectively. Matching for the DR antigens 11-14, or for some DR alleles only detectable by genomic typing, further improved graft survival, but the differences did not reach statistical significance. Matching also for the serologically defined HLA-A and -B antigens did not significantly further improve overall graft survival, but some effects for grafts surviving at least 1 year were observed. Among recipients of grafts mismatched for zero, one, or two HLA-DR antigens, acute rejection episodes were experienced in 48%, 64% (P<0.001), and 82% (P<0.001), respectively, within the first 3 months. HLA-A and -B mismatches showed no significant correlation to acute rejection episodes. CONCLUSION: Matching for the DR antigens 1-10 significantly secures and prolongs the survival of first cadaveric renal grafts. Our results also show that DR 1-10 antigen-matched combinations can often be obtained even in rather small recipient pools, when actively sought for.

Adolescent↗

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.

Adolescent↗