Proteinuria 1 year after renal transplantation is associated with impaired graft survival in children

Effects of the strict control of blood pressure in pediatric renal transplant recipients-ESCORT trial

OBJECTIVES

Strict BP control can retard progression of CKD in children. This prospective 3-year randomized controlled trial is aimed to investigate whether strict BP control can retard progression of chronic allograft dysfunction.

METHODS

Twenty-three pediatric patients were randomly selected to the standard BP group (STAND, target 24-hour MAP 50-95th percentile, n = 11) or the intensified BP group (INTENS, target 24-hour MAP <50th percentile, n = 12). The primary endpoint was an annual reduction in eGFR (Schwartz formula, mL/min/1.73 m² /y), secondary graft survival, BP, proteinuria, and safety.

RESULTS

A total of 21 children (age at entry 11.2 (range 6.2-16.8) years) completed the study, with 73% of children in INTENS and 70% of children in STAND group reached their goal BP. Ambulatory indexed 24-hour MAP decreased significantly in INTENS group (from 0.94 (range 0.86-1.17) to 0.85 (range 0.79-1.01, P < 0.01)) but not in STAND group (from 0.93 (range 0.85-1.07) to 0.90 (range 0.84-1.01)). Proteinuria did not change significantly in either group (22.1 mg/mmol creatinine to 15.3 in STAND group vs 25.7 to 11.8 in INTENS group). The annual reduction in eGFR did not differ between the INTENS and STAND groups (-1.9 mL/min/1.73 m² /y (range +6.4 to -14.3) vs -0.9 (range +4.0 to -8.5)).

CONCLUSION

This first randomized controlled trial on strict BP control has demonstrated that strict BP control is feasible in 73% of children but the strict BP control does not lead to retardation of graft function decline in comparison with standard BP control. However, the results need to be interpreted with caution keeping the major limitation of the study, that is, small sample size in mind.

Proteinuria in pediatric renal transplant recipients

Proteinuria has been shown to be an important and potentially treatable risk factor for graft loss. The aim of this study was to evaluate prevalence, etiology, and outcome of proteinuria during the follow-up of children with renal transplantation. We retrospectively reviewed the files of renal transplanted children between 2006 and 2016 in our center. All patients were interpreted with respect to the demographic data and clinical and laboratory features including information about proteinuria. Chi-square test and Mann-Whitney U test were used for analysis. Fifty-two children were eligible for the study. Proteinuria was observed in 34 (65%) and nephrotic range proteinuria was detected in 5 (9.6%) patients. Etiology of proteinuria could be identified in 21 patients. Acute rejection and uncontrolled hypertension were the most frequent causes of proteinuria. Proteinuria had resolved during the follow-up in 59% of the patients. We found that children with and without proteinuria had similar glomerular filtration rate at the end of 50 months of follow-up period. Proteinuria seems to be a common complication in renal transplant recipients. Graft functions can be preserved by immediate evaluation of increasing proteinuria, and by fixing treatable causes rapidly and efficiently during the follow-up in majority of the patients.