Objectives: To evaluate the outcomes, complications, causes of graft loss, and patient and graft survival in pediatric renal transplant.

Materials and Methods: We conducted a retrospective study using the records of 32 children who had a renal transplant between February 2007 and October 2014.

Results: All donations were intrafamily, and all patients had a living donor: the patient’s mother in 56.3%, the father in 40.6%, and a brother in 3.1%. The sex ratio was 0.77. Before transplant, 65.6% of patients were on hemodialysis, and 15.6% were on peritoneal dialysis. Preemptive transplant was performed in 3.1%. Medical complications occurred in 77% of patients; of these, 59% were urinary tract infections, and 9.83% were acute rejection. Surgical complications occurred in 22% of patients; 18.8% of these complications were urologic, and 3.2% were vascular. Patient and graft survival rates were estimated at 96.4% and 89.6% at 1 year and 83.4% and 65.5% at 7 years.

Conclusions: In our series, medical complications were more frequent than surgical, but the latter were the main cause of graft loss. Patient survival was generally good.

Key words : Evaluation, Outcomes, Primary kidney disease

Introduction

Kidney transplant is the preferred treatment for end-stage renal disease in children. It confers better survival, skeletal growth, health-related quality of life, and neuropsychological development than dialysis.1 The best results are achieved with pre­emptive transplant and a living-related donor.

Materials and Methods

We conducted a retrospective study using the records of children who had a renal transplant at our center over a period of 93 months: from February 2007 to October 2014. We collected demographic data on both recipients and donors. We also collected information regarding the primary kidney disease, dialysis modalities used, results of human leukocyte antigen matching, the type of induction and maintenance therapy, the incidence of complications, and patient and graft survival.

Statistical analyses were performed using software (SPSS version 11.0, SPSS Inc., Chicago, IL, USA). Data are reported as means +/- standard deviation.

Results

Our center is an adult kidney transplant unit, but 15% of all renal transplants performed over the course of the study period were in children. Of the 32 pediatric recipients, 69% were male, and the male-to-female sex ratio was 2.2. The mean patient age was 12.94 ± 3.66 years (range, 5-18 y). The mean patient weight was 31.97 kg (range, 16-50 kg).

The primary kidney disease was undetermined in 40.6% of patients. The main known causes of kidney failure were congenital disorders such as obstructive nephropathy and malformations of the kidney or urinary tract (Figure 1). Before transplant, 65.6% of recipients were on hemodialysis, 15.6% were on peritoneal dialysis, and 15.6% were switched from peritoneal dialysis to hemodialysis because of several episodes of peritonitis. Preemptive transplant was performed in a single recipient (3.1%).

All patients used living-related donors: the patient’s mother in 56.3%, the father in 40.6%, and a brother in 3.1%. The male-to-female sex ratio was 0.77. Human leukocyte antigen matching was identical in 6.3% of patient-donor pairs, semi-identical in 90.6%, and nonidentical in 3.1%. The induction therapy was based on antithymocyte globulin in most recipients (90.6%). Basiliximab-based therapy was used in 2 recipients (6.2%); no induction therapy was used, neither ATG nor basiliximab in recipients who had identical HLA with their donors Tacrolimus was the most frequently used calcineurin inhibitor in maintenance therapy (65.5% of patients), followed by cyclosporine in 28.1%. A total of 6.3% of recipients did not receive any calcineurin inhibitor.

The complications were mainly medical (77%), with urinary infections seen in 59% and acute rejection in 9.85%. Surgical issues represented 22% of all complications, including 6 instances of ureteral stenosis, 1 of lymphocele, 1 of venous thrombosis, and 5 of vesicoureteral reflux. Patient and graft survival were estimated at 96.4% and 89.6% at 1 year and 83.4% and 65.5% at 7 years (Figures 2 and 3).

Discussion

A high percentage of kidney disease has an undetermined cause, partly because of the poor state of genetic exploration. Surgical complications are the main cause of graft loss in the pediatric population. Our observed patient survival is consistent with the outcomes described in the literature.^2,3 Further research is needed on this topic, and large-scale studies are indicated.

References:

1. Winterberg P, Warshaw B. Renal transplantation in children. In: Morris P, Knechtle SJ. Kidney Transplantation–Principles and Practice. 7th ed. Philadelphia, PA: Saunders Elsevier; 2014:606-642.
2. Van Arendonk KJ, Boyarsky BJ, Orandi BJ, et al. National trends over 25 years in pediatric kidney transplant outcomes. Pediatrics. 2014;133(4):594-601.
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3. Shapiro R, Scantlebury VP, Jordan ML, et al. Pediatric renal transplantation under tacrolimus-based immunosuppression. Transplantation. 1999;67(2):299-303
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