Transplantation issues in pediatric retinal-renal syndromes

A total of seven children with retinal-renal syndromes who developed end-stage renal disease have been transplanted in our centre over the past decade. This group of children did not have difficulty with frequent rejection and had good graft function. Three children died of gram-negative sepsis, which appeared to be related to their comorbid conditions and history of recurrent urinary tract infections prior to and after transplantation. Each of the three children had risk factors for gram-negative sepsis with peritoneal catheter in situ, urinary tract infection, and gastrointestinal surgery, respectively. Gram-negative sepsis is a significant risk factor for this patient group and possible interventions, including removal of peritoneal catheters at the time of transplantation, antimicrobial prophylaxis if there has been a history of recurrent urinary tract infection, antibiotic coverage during gastrointestinal surgery, and early access to medical care, should be incorporated into the care of this group of patients. All children had significant weight gain and increased posttransplant body mass index (BMI), irrespective of their size prior to transplantation. These findings are in comparison to age- and gender-matched controls. Increased weight and BMI were not related to availability of food or dietary education, and there was no evidence of a difference in steroid exposure. In addition, there was no evidence of hyperglycemia in this group although diabetes mellitus was found in the adult counterparts. Hyperphagia was described by the patients and families and this was addressed. The hyperphagia may have been secondary to: (1) CNS aspects of the disease; (2) improved appetite with resolution of uremia; (3) aggravation by glucocorticoid therapy; or (4) peripheral insulin resistance. The latter was not addressed in this study. The other aspect that may explain the differences in weight gain between children with retinal-renal syndromes versus other children after renal transplant may involve a lack of physical activity due to the limitations caused by visual impairment. Renal transplantation can be successful in this group of children with allograft function, comparable to other groups. Previously, we investigated congenital hepatic fibrosis in this group, which does not appear to be significantly aggravated after renal transplantation in these study patients. The two major risk factors that need to be addressed in this population are the extreme weight gain and a significant risk of gram- negative sepsis leading to death. The contribution of other factors to morbidity and mortality, such as hepatic fibrosis, will require long-term monitoring and follow-up in this unique patient population.