# Diagnosis and Endovascular Management of Transplant Renal Artery Stenosis: A Retrospective Two-Decade Study

## TL;DR

This study shows that angioplasty and stenting are safe and effective treatments for kidney artery narrowing in children after kidney transplants.

## Contribution

A retrospective two-decade analysis of endovascular treatment outcomes for transplant renal artery stenosis in pediatric patients.

## Key findings

- PTA with or without stenting improved blood pressure control and reduced antihypertensive medication use in children with TRAS.
- No complications occurred during procedures, and re-interventions were required in some cases.
- TRAS prevalence was higher in cadaveric transplants compared to living-related transplants.

## Abstract

Introduction

Transplant renal artery stenosis (TRAS) is a potentially treatable posttransplant complication, primarily presenting with arterial hypertension and allograft dysfunction. Its prevalence in children with posttransplant hypertension ranges from 5% to 15%. Diagnosis is typically made through invasive angiography following suspicion raised by echo Doppler findings. Treatment options include medical therapy, percutaneous transluminal angioplasty (PTA)/stenting, and surgical revascularization. This study aimed to assess the efficacy, complications, and outcomes of PTA/stenting procedures in children with TRAS.

Methods

We reviewed all pediatric patients who underwent renal transplantation in Serbia between June 2001 and February 2023 to identify cases of TRAS treated with PTA. Statistical analysis was performed to compare pre- and post-intervention arterial vessel diameters, serum creatinine levels, estimated glomerular filtration rate (eGFR), mean blood pressure, systolic and diastolic blood pressure indices, and the number of antihypertensive medications used.

Results

Seven patients underwent PTA with or without stent placement for TRAS. None were treated solely with medical therapy or surgical intervention. The overall prevalence of TRAS was 6.32%, higher in cadaveric transplants (11.11%) compared to living-related transplants (3.39%). Of the seven patients, five underwent PTA alone, while two required stent placement. Two of the five PTA patients required re-interventions, resulting in a total of seven angioplasty procedures. No complications occurred following the procedures. After a mean follow-up of 56.86 ± 45.76 months, patients demonstrated improved blood pressure control and reduced use of antihypertensive medications. While the mean eGFR showed a nonsignificant improvement, one patient with severe concomitant cytomegalovirus disease progressed to grade IV chronic kidney disease.

Conclusions

PTA, with or without stenting, appears to be an effective and safe treatment for TRAS in children, with immediate and intermediate-term results comparable to those reported in the literature. Stent placement may be particularly suitable for adolescents who have completed their growth phase.