Causes of kidney allograft loss in a large pediatric population at a single center

Graft loss due to recurrent disease in pediatric kidney transplant recipients on a rapid prednisone discontinuation protocol

Recurrent disease is the fourth most common cause of graft loss (GL) in pediatric KTx recipients. We studied the incidence of recurrent disease and GL due to recurrent disease in pediatric KTx recipients on a RDP protocol. Between 2002 and 2010, we performed 74 KTxs in patients aged 5-18 yr using an RDP protocol, 25 (34%) were at risk of recurrence of primary disease. Outcomes were compared to 69 historical controls (18 [26%] at risk of recurrence), KTx between 1996 and 2000. Follow-up period was 39 ± 25 months in RDP and 124 ± 38 months in controls. The incidence of recurrent disease at three yr post-KTx was 16% in RDP and 28% in controls (p = NS). Mean time to recurrent disease was 22 ± 26 months in RDP and 46 ± 48 months in controls (p = 0.54). Nine (12%) grafts were lost in the RDP group (1-recurrence) and 32 (46%) in the control group (4-recurrence). Time to GL was 85 months in the RDP recipient and 46 ± 21 months in controls. An RDP protocol in pediatric KTx recipients may not be associated with increased risk of graft loss due to recurrent disease.

Two decades of pediatric kidney transplantation in a multi-ethnic cohort

This study evaluated a 20-yr experience in kidney transplantation in children from a predominantly Hispanic community. A retrospective analysis was carried out in children who received kidney transplants from 1985 to 2005. Of 124 kidney transplants, 81 (65%) were from LD. Racial distribution was Hispanic (48%), followed by AA (24%) and Caucasian (26%). First yr allograft survival was similar in LD and DD and significantly better in LD until seven yr post transplant. eGFR <60 mL/min/1.73 m(2) at one yr post transplant was associated with a median allograft survival of 3.3 yr, compared to 16 yr in those with eGFR > or = 60 mL/min/1.73 m(2) (p < 0.0001). Graft loss in the first five yr was from non-adherence, recurrence of disease, and infections. Those of AA race were more likely to receive a DD and have low socioeconomic status and the poorest median allograft survival compared to Hispanics and Caucasians (6 vs. > or =15 yr; p < 0.001). In conclusion, this predominantly Hispanic cohort emphasizes the disadvantaged profile of AAs compared to other racial groups. Strategies to improve supportive services and living donations in minority populations need to be developed. Long-term renal allograft survival is achievable if GFR is maintained >60 mL/min/1.73 m(2).

Characteristics of long-term live-donor pediatric renal transplant survivors: a single-center experience

OBJECTIVES

To study the characteristics and the predictors of survival observed in our pediatric live-donor renal transplant recipients with an allograft that functioned for more than 10 yr.

METHODS

One hundred fifteen children underwent renal transplantation between 1976 and 1995. Of these, 30 had functioning allografts for more than 10 yr (range, 11-18). The patients included 18 males and 12 females, with a mean age at transplantation of 13 yr (range, 5-18). Characteristics of the patients, data on graft survival, and determinants of outcome were obtained by reviewing all medical charts.

RESULTS

At most recent follow-up (January 2005), the mean daily dose of azathioprine was 1.2 mg/kg (range, 1-2) and that of prednisone was 0.16 mg/kg (range, 0.1-0.2). Mean creatinine clearance was 72 mL/min per 1.73 m(2) (range, 45-112). Acute rejection occurred in 14 (47%) patients. Seven patients had one episode, five had two episodes, and two had three episodes of acute rejection. Three patients (10%) developed malignancy. A substantial proportion of patients (44%) were short, with a height standard deviation score (SDS) less than -1.88, which is below the third percentile for age and gender. One quarter of the patients, more commonly the females, were obese. Other complications included osteoporosis in 16 (53%) patients, avascular bone necrosis in four (13%), post-transplantation diabetes mellitus in three (10%), and hypertension in 18 (60%). Twelve (40%) patients were married and 27% had children post-transplantation. The independent determinants of long-term graft survival were acute rejection and post-transplant hypertension.

CONCLUSION

Despite good renal function, long-term pediatric renal transplant survivors are at risk of significant morbidity. The determinants of long-term graft survival are acute rejection and post-transplant hypertension.

Long-term follow-up of renal transplantation in children: a Dutch cohort study

BACKGROUND

Few data exist on long-term morbidity, overall survival, and graft survival of pediatric renal transplantation.

METHODS

The authors performed a long-term cohort study in all Dutch patients, born before 1979, with onset of end-stage renal disease (ESRD) between 1972 and 1992 at age 0 to 15 years. Data on graft survival and determinants of outcome were obtained by reviewing all medical charts. The health status was assessed by cross-sectional examination of surviving patients.

RESULTS

Three hundred ninety-seven transplantations were performed in 231 of all 249 patients, of whom 25 died with a functioning graft. Cardiovascular disease was the most prominent cause of death. Graft survival estimates for all transplantations were 59.2%, 45.3%, 35.4%, and 30.3% at 5, 10, 15, and 20 years, respectively. In comparison with azathioprine, cyclosporine as the immunosuppressant was associated with increased graft survival in retransplantations but not in first transplantations. Cross-sectional examination was performed on 110 patients. In 44 patients, the most recent graft survival exceeded 15 years. Co-morbidity was found in 40% of all patients; motor, hearing, or visual disabilities were found in 19%. Bone disease, headaches, itching, and tremors were the most reported disabling problems. Cyclosporine use was associated with hypertension and a history of epilepsy. Compared with all age-matched Dutch inhabitants, the educational attainment was low, and unemployment and parental dependency were high.

CONCLUSIONS

The authors' results emphasize the need for reducing cardiovascular disease and metabolic bone disease in pediatric ESRD, a policy toward less toxic antirejection therapy, a more strict treatment of hypertension, and more attention for schooling and social development toward independence.

Mycophenolate mofetil-induced reversal of glomerular filtration loss in children with chronic allograft nephropathy

BACKGROUND

Mycophenolate mofetil (MMF) has been used for the treatment of chronic allograft nephropathy (CAN) in adults with inconsistent results, but data in children are rare. To evaluate its impact on advanced CAN, we studied changes in glomerular filtration rate (GFR) and the correlation of GFR changes to histology.

METHODS

Thirty-six children (13.1+/-3.6 years) with a progressive decline in GFR of 16.9+/-12.4 mL/min per 1.73 m2/year and biopsy confirmed CAN 4.3+/-2.9 years after transplantation were studied. MMF was added to conventional immunosuppression (IS) consisting of cyclosporine (CsA) and prednisolone (n=26) or tacrolimus (n=1) or replaced azathioprine in triple IS (n=9). Alterations of GFR were correlated to histologic guidelines according to the Banff chronic score (BCS).

RESULTS

One year after conversion, 22 (61%) children showed a rise in GFR (7.5+/-6 mL/min per 1.73 m2), 8 (22%) remained stable, and 6 (17%) showed a further decline of GFR (7.4+/-2 mL/min per 1.73 m2). Mean CsA trough levels were 114 ng/mL before and 98 ng/mL 1 year after conversion. MMF side effects required dose reduction in 14 children. Children responding to MMF with increasing GFR showed a trend toward less fibrosis, less incidence of vasculopathy, and transplant glomerulopathy in the initial biopsy but had a similar incidence of borderline tubulitis compared with the other groups.

CONCLUSIONS

Cotreatment with MMF reversed the progressive loss of GFR in approximately two thirds of children with CAN for at least 1 year. Less chronicity signs in histology seem to indicate a more favorable response to treatment.

Improved late graft survival and half-lives in pediatric kidney transplantation: a single center experience

We evaluated variables associated with improved late graft survival in 290 children transplanted between 11/1/1984 and 12/31/1997, and who had > 1 year graft survival. We studied the following variables: age, gender, race, primary disease (diseases prone to recurrence, i.e. hemolytic uremic syndrome, focal segmental glomerulosclerosis or oxalosis vs. others), primary vs. retransplant; donor source, acute tubular necrosis, acute rejection episodes in the first year, transplant era and discharge serum creatinine. Graft half-life was defined as the time taken for 1/2 of the grafts functioning at 1 year to fail. There were 205 living donor and 85 cadaveric transplant. The cumulative graft survival at 5 and 10 years was 88% and 75% for living donor, and 72% and 46% for cadaveric, respectively. Multivariate analyses showed a higher late graft survival to be associated with: no acute rejection episodes (risk ratio 0.16, p = 0.0001), age 2-5 years (risk ratio 0.24, p = 0.0007), living donor (risk ratio 0.46, p = 0.017), primary nonrecurrent disease (risk ratio 0.29, p = 0.001), Caucasian race (risk ratio 0.40, p = 0.006). A high half-life was seen with living donor transplant (21.3 years) and the age group 2-5 years (27.5 years). Further, living donor patients with no acute rejection episodes had the best half-life of 37.6 years, while children with hemolytic uremic syndrome, focal segmental glomerulosclerosis or oxalosis had the lowest overall half-life of 5.6 years. This study finds that living donor, no acute rejection episodes, age 2-5 years, Caucasian race and having a disease not prone to recurrence are strong predictors of late graft survival. Hence, preferential use of living donor and prevention of acute rejection episodes in the first year are key variables that can improve long-term renal graft survival in children.

Morbidity from congenital hepatic fibrosis after renal transplantation for autosomal recessive polycystic kidney disease

Presentation of autosomal recessive polycystic kidney disease (ARPKD) ranges from severe renal impairment and a high mortality rate in infancy to older children and adolescents with minimal renal disease and complications of congenital hepatic fibrosis (CHF), cholangitis and portal hypertension. Renal transplantation improves prognosis but it is unclear whether CHF in transplanted children follows the same clinical course as in older children with less severe renal disease. The aim of this study was to evaluate morbidity from CHF in ARPKD post renal transplantation. Data were analyzed for six males and eight females, transplanted for ARPKD (mean age 8.3 years, range 1-22.3 years) at the University of Minnesota between 1972 and 1998. Follow-up was for a mean of 14.5 years (range 3.1-33.6 years). One and 5 years patient survival rates were 93% and 86%, respectively. Overall five patients (36%) died; 4/5 deaths were related to CHF. Causes of death were hepatic failure immediately post transplant (n = 1), septicemia related to bile duct dilatation (n = 3) and multiorgan failure (n = 1). One and 5years graft survival rates were 87% and 70%, respectively. One patient had a combined liver-kidney transplant and two were re-transplanted. Initial signs of CHF were splenomegaly (n = 5), hepatosplenomegaly (n = 4) and gastrointestinal bleed (n = 2). Progression of CHF through childhood included hypersplenism (n = 7), esophageal varices with gastrointestinal bleeding (n = 5) and bile duct dilatation (n = 5). Portal hypertension was treated with portosystemic shunt (n = 3), sclerotherapy (n = 2), banding of varices (n = 1) and transjugular intrahepatic portosystemic shunt (n = 1). Of the nine survivors (mean age 12.8 years) 78% have functioning grafts (one liver-kidney transplant), 63% have portal hypertension and 22% have asymptomatic biliary dilatation. Complications of CHF developed in 79% of children who received a renal transplant for ARPKD. Mortality related to CHF occurred in 29% and accounted for 80% (4/5) of the deaths.

Course of renal allograft histopathology after transplantation in early childhood

BACKGROUND

We report a long-term prospective follow-up of renal allograft histology in children <5 years of age at transplantation (Tx).

METHODS

Fifty-one kidney allograft recipients were prospectively followed for renal allograft histology and function up to 7 years after Tx. Twenty patients were recipients of kidneys from living related donors, and 31 were cadaveric kidney recipients. All patients received triple immunosuppression. Biopsies were analyzed according to the Banff classification and scored semiquantitatively. The "chronic allograft damage index" (CADI) was calculated.

RESULTS

Five of seven grafts were lost because of nephrosis in patients with congenital nephrotic syndrome of the Finnish type. Most of the biopsies (52-69%) were considered normal (Banff classification), and the proportion with chronic allograft nephropathy did not increase with time. The median CADI score was 2.5 (scale: 0-36) at 1.5 years and 3.5 at 7 years. Recipients with an acute rejection episode had higher CADI scores than recipients without acute rejection episode. Patients with a high CADI score at 3 years had inferior graft function at 5 years. Recipients <2 years of age had CADI scores and numbers of acute rejection episode similar to recipients between 2 and 5 years of age. However, in contrast to the older recipients, the younger recipients did not improve their absolute glomerular filtration rate with time.

CONCLUSIONS

The long-term histopathological findings were mostly mild and stable with time. Acute rejection episode had an impact on these changes and CADI predicted later graft function. Nonimmunological risk factors seem to be more important in the youngest recipients.

Kidney transplanted children come of age

BACKGROUND

The aim of renal replacement therapy in children is to restore their potential for normal growth and development in order to reach mature adulthood. Because pediatric kidney transplantation started in the late 1960s, it is now possible to document the progress and outcome of these patients from transplantation in childhood to survival into adulthood.

METHODS

In this single-center study, all 150 children born before December 1977 and having received a kidney transplant between 1970 and 1993 were selected for long-term follow-up. The mean age at transplantation was 12.1 years (range 3.2 to 16.7), and the mean follow-up was 13.1 years (range 2.0 to 25.0). In December 1995, 124 grown-up patients with a mean age of 25.4 years (range 18.4 to 40.3) were alive, 89 with a functioning graft. Fifty had the first graft functioning longer than 10 years. The fate of all patients was traced, and those living were analyzed in regard to their somatic and socioeconomic states.

RESULTS

The actuarial 25-year survival rate for the patients was 81%, and for the first graft it was 31%. The best graft survival rates were observed after living related donation, preemptive transplantation, and immunosuppression with cyclosporine. The latter benefit, however, vanished after eight years. The mean creatinine clearance declined over the years from 76 to 45 ml/min/1.73 m2, and the incidence of hypertension increased to more than 80% of the patients. Malignancies occurred in 2.6%. Final height was stunted in 44% of noncystinotic patients, whereas all patients with cystinosis were extremely growth retarded. Twenty-seven percent suffered from additional disabilities. A majority of adult patients were rehabilitated in regard to education and socioeconomic status, and 14% were unemployed.

CONCLUSIONS

The results indicate that renal transplantation in children leads to a high degree of rehabilitation in adulthood. The life of a kidney transplant, however, is limited, which points out the need for more specific immunosuppression with fewer side-effects in order to reach the goal of lifelong graft function.

A novel approach to the treatment of chronic allograft nephropathy

BACKGROUND

Progressive deterioration of renal function in kidney transplant recipients is the leading cause of graft failure. Both nonimmunologic and immunologic mechanisms contribute to this deterioration.

METHODS

Twenty-eight cyclosporine (CsA)-treated renal transplant recipients (21 cadaveric, 5 living, 2 simultaneous kidney-pancreas) with progressive deterioration of renal function were prospectively enrolled in a clinical trial and had their immunosuppressive regimen changed 24.3+/-7.7 months after transplant. All patients had their CsA dose reduced by 50%, azathioprine was discontinued, and mycophenolate mofetil was added to the medical regimen. The mean creatinine of the patients at the initiation of the change in immunosuppression was 3.5+/-1.2 mg/dl (range 1.9 to 6.2 mg/dl).

RESULTS

Before the change in immunosuppression, the mean loss in renal function as indicated by the least-squares slope of the reciprocal of creatinine versus time was -0.006+/-0.002 (mg/dl)-1 per month. The change in immunosuppression significantly decreased the rate of loss in renal function for most patients when compared with their pretreatment values with a mean slope of 0.007+/-0.003 (mg/dl)-1 per month (P=0.003). Renal function improved in 21 of 28 patients. Only one patient had continued deterioration of renal function. In a multivariate analysis adjusting for CsA dose, mean arterial blood pressure, and baseline creatinine, the change in immunosuppression was significantly associated with improved renal function (P=0.02). There were no acute rejections after the immunosuppression change.

CONCLUSIONS

We conclude that adding mycophenolate mofetil and reducing CsA in patients with chronic deterioration of graft function is well tolerated and results in a short-term improvement in renal function.

Transplant allograft loss in the adolescent patient

The case of an adolescent transplant recipient who lost her allograft as a result of medication noncompliance serves as the focus of this multidisciplinary review. The discussion that follows includes (1) a review of current graft survival data for adolescent renal transplant recipients with particular attention to the occurrence of medication noncompliance in this patient population, (2) an overview of normal growth and development as it applies to the adolescent patient with chronic disease, and (3) proven treatment strategies with emphasis on the needs of the adolescent transplant patient. The discussion is intended to provide the reader with a greater understanding and appreciation of developmental issues that influence adolescent behavior and, in turn, impact medical care. It is also hoped that the information provided will be used by health care providers to promote adherence to a chronic medical regimen on behalf of the adolescent transplant recipient.

Renal allograft survival according to primary diagnosis: a report of the North American Pediatric Renal Transplant Cooperative Study

The data base of the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) was used to examine the effect of primary diagnosis on the outcome of renal transplantation in children. The relative risk of graft failure for eight diagnostic groups was determined, with patients with congenital and structural anomalies of the urinary tract serving as the reference group. Covariate analysis was used to control for the effects of age, race and transfusion history in recipients of living-related donor kidneys, and for age, donor age, antilymphocyte prophylaxis, prior transplantation, prior dialysis and cold ischemia time in recipients of cadaver kidneys. In recipients of living-related donor kidneys, the lowest graft failure rates were associated with the diagnoses of cystinosis, familial nephritis and hemolytic uremic syndrome (HUS), while the highest failure rates were observed in patients with a primary diagnosis of congenital nephrotic syndrome (CNS) or focal segmental glomerulosclerosis (FSGS). In cadaver allograft recipients, the lowest graft failure rates were associated with primary diagnoses of glomerulonephritis, congenital/structural disease and cystinosis, while patients with FSGS, HUS and CNS had the highest graft failure rates. This study suggests that patients with a primary diagnosis of cystinosis have superior outcomes, while the diagnoses of FSGS and CNS carry with them the highest risks of graft failure.